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Country‐level optimism was negatively related to GDP per capita, population density, and democratic norms and positively related to income inequality and perceived corruption

International Optimism: Correlates and Consequences of Dispositional Optimism across 61 Countries. Erica Baranski  Kate Sweeny  Gwendolyn Gardiner  David C. Funder  Members of the International Situations Project. Journal of Personality, August 7 2020. https://doi.org/10.1111/jopy.12582

Abstract
Objective: The current exploratory study sought to examine dispositional optimism, or the general expectation for positive outcomes, around the world.

Method: Dispositional optimism and possible correlates were assessed across 61 countries (N = 15,185; mean age = 21.92; 77% female). Mean‐level differences in optimism were computed along with their relationships with individual and country‐level variables.

Results: Worldwide, mean optimism levels were above the midpoint of the scale. Perhaps surprisingly, country‐level optimism was negatively related to GDP per capita, population density, and democratic norms and positively related to income inequality and perceived corruption. However, country‐level optimism was positively related to projected economic improvement. Individual‐level optimism was positively related to individual well‐being within every country, although this relationship was less strong in countries with challenging economic and social circumstances.

Conclusions: While individuals around the world are generally optimistic, societal characteristics appear to affect the degree to which their optimism is associated with psychological well‐being, sometimes in seemingly anomalous ways.

The Political Right Is Not More Credulous: Experimental Evidence Against Asymmetric Motivations to Believe False Political Information

Is the Political Right More Credulous?: Experimental Evidence Against Asymmetric Motivations to Believe False Political Information. Timothy Ryan and Amanda Aziz. The Journal of Politics, Aug 2020. https://www.journals.uchicago.edu/doi/pdfplus/10.1086/711133

Abstract: Recent political events have galvanized interest in the promulgation of misinformation—particularly false rumors about political opponents. An array of studies provide reasons to think that harboring false political beliefs is a disproportionately conservative phenomenon, since citizens with affinity for the political right endorse more false information than people with affinity for the left. However, as we discuss below, past research is limited in its ability to distinguish supply-sideexplanations for this result (false information is spread more effectively by elites on the right) from demand-side explanations (citizens who sympathize with the right are more likely to believe false information upon receipt). We conduct an experiment on a representative sample of Americans designed specifically to reveal asymmetries in citizens’proclivity to endorse false damaging information about political opponents. In a contrast with previous results, we find no evidence that citizens on the political right are especially likely to endorse false political information.

Keywords: Rigidity of the Right; Ideology; Motivated reasoning; Conspiracy beliefs

The unexpected small decline in Neuroticism suggests that, during the acute phase of COVID-19, feelings of anxiety and distress may be attributed more to the pandemic than to one’s personality

Change in five-factor model personality traits during the acute phase of the coronavirus pandemic. Angelina R. Sutin et al. PLoS, August 6 2020. https://doi.org/10.1371/journal.pone.0237056

Abstract: The rapid spread of the coronavirus and the strategies to slow it have disrupted just about every aspect of our lives. Such disruption may be reflected in changes in psychological function. The present study used a pre-posttest design to test whether Five Factor Model personality traits changed with the coronavirus outbreak in the United States. Participants (N = 2,137) were tested in early February 2020 and again during the President’s 15 Days to Slow the Spread guidelines. In contrast to the preregistered hypotheses, Neuroticism decreased across these six weeks, particularly the facets of Anxiety and Depression, and Conscientiousness did not change. Interestingly, there was some evidence that the rapid changes in the social context had changed the meaning of an item. Specifically, an item about going to work despite being sick was a good indicator of conscientiousness before COVID-19, but the interpretation of it changed with the pandemic. In sum, the unexpected small decline in Neuroticism suggests that, during the acute phase of the coronavirus outbreak, feelings of anxiety and distress may be attributed more to the pandemic than to one’s personality.

Discussion

The present research suggests modest acute personality change during the initial stages of the coronavirus outbreak in the United States. Contrary to our hypothesis, there was a small decline in Neuroticism rather than the expected increase. This change in Neuroticism was only apparent among individuals who were not in quarantine/isolation. We likewise did not find the expected increase in Conscientiousness, and there was some evidence that the current social environment may have changed the meaning of an item. In exploratory analyses, there was modest evidence that isolation status moderated trait changes in Conscientiousness, Openness, and Agreeableness, as well as for Neuroticism.

Personality traits tend to be stable over time and resistant to normative life events that are stressful [8]. Of the five traits, there is the most evidence that Neuroticism may be the most reactive to stress. When individuals experience a great amount of distress, either through an extremely aversive event [17–19] or a depressive episode [9], Neuroticism tends to increase. A similar but weaker trend is found for long-term psychological responses to natural disasters, such as after the Christchurch Earthquake [20]. Likewise, interventions to improve mental health decrease Neuroticism [10]. Given the stress and anxiety over the coronavirus, we had expected Neuroticism to increase. Instead, the opposite pattern emerged. This decrease may be due to contrast effects. That is, reminders of the collective stress and anxiety that the world was under were everywhere: During the 10 days of the posttest data collection, there was significant volatility and losses in the stock market [21] (marker of economic anxiety), essential household products such as toilet paper were sold out across the country [22] (marker of consumer anxiety), and national polls indicated that 70% of American adults were concerned or very concerned about the virus in their community [23] (marker of individual anxiety). Feelings of personal stress and anxiety may be attributed less to the self when there is a tremendous amount of stress and anxiety experienced through the whole of society. In such a context, there might be an attenuated tendency to perceive and rate oneself as emotionally distressed as compared to other people. The stress and anxiety participants felt may have been ascribed to the external situation rather than their own personality. It is important to note that participants with pretest data but no posttest data scored higher in Neuroticism. This difference in attrition may have had an effect on the pattern of results. For example, as individuals higher in neuroticism were lost to follow-up, it is possible that this more emotionally vulnerable group responded differently to the pandemic. It is also of note, however, that the overall pattern that we found is consistent with anecdotal reports of decreases in anxiety among individuals who typically suffer from anxiety [24].

We did not find evidence for change in Conscientiousness. We hypothesized that the ubiquitous public health messaging to be more attentive to personal behavior would translate into an overall increase in a trait tendency to be conscientious, particularly the facet of Responsibility. Rather than Responsibility, however, we found only modest evidence for an increase in the facet of Productiveness, which indicated that individuals saw themselves as more efficient and persistent in this crisis. There was, however, a fascinating pattern for Dutifulness. Dutifulness measures the tendency to adhere strictly to ethical principles [15]. This trait tendency decreased between pre- and post-test, a change that primarily occurred in participants younger than 65 (i.e., working-aged adults). This decrease was due entirely to declines on one item about going to work/school when not feeling well. In pre-pandemic times, this item was a fairly good marker of an individual’s willingness to follow through on their commitments. The swift changes in the social landscape, however, may have changed the meaning of this item. Now, rather than a marker of conscientiousness, going to work/school while sick may be a marker of recklessness or antagonism, whereas staying at home and protecting one’s community is conscientious. It is an example of how social context can (rapidly) change the meaning of an item and how it defines the trait it measures.

Approximately one-quarter of our sample reported being in isolation/quarantine within the last month. Our exploratory analysis suggested modest change in personality by isolation status. Of most note, isolation status moderated change in Neuroticism such that the decline in Neuroticism only occurred for those not in quarantine. Further, there was a cross-over interaction for the Depression facet: Individuals not in quarantine declined, whereas those in quarantine increased in a trait tendency toward depressed affect. Increases in depressed affect and other aspects of negative emotionality are common while in quarantine, and the effects may or may not be long lasting [25]. More generally, quarantine might provoke anxiety that is not assuaged by the stress and anxiety felt by the rest of the population. In addition to Neuroticism, isolation also moderated change in Openness, Agreeableness, and Conscientiousness. In all cases, these traits declined among individuals in isolation, specifically the facets of Curiosity, Trust, and Organization, respectively. The circumstances around isolation may lead to boredom and erode trust. There may also be less pressure to be organized because there is less that needs to get done in a timely manner. It is also of note that there were baseline differences in personality prior to quarantine. That is, individuals who go into quarantine had higher baseline levels of Neuroticism and lower Agreeableness and Conscientiousness. Individuals with these traits may be at greater risk of exposure through either who they interact with and/or they work jobs that put them at higher risk of exposure. Individuals higher in Neuroticism may also perceive more threat and go into quarantine to feel safer. There may also be bias associated with these traits in how quarantine/isolation is interpreted (e.g., safer at home may be interpreted as quarantine). We could not tease apart these different possibilities.

FFM personality traits are known to be stable [26] with normative changes across the lifespan [27] and are also known to be relatively resistant to change after normative life events [8]. As such, there would be no expectation that personality traits would change over just six weeks in normal circumstances. The coronavirus pandemic, however, is unprecedented in its disruption of daily life for most of the population. It was thus possible that it would also have an unprecedented effect on personality. As described above, extremely aversive and stressful events are associated with change in personality [17, 19], and the global scale of the current stressful event may have had a widely felt impact. And yet, even with the widespread fears over health consequences of complications of COVID-19, the economic uncertainty, and restrictions on daily life, personality traits have been mostly resistant to change. These findings support theoretical accounts of personality traits that argue for their stability [28], even in the face of acute environmental stressors. It may be the case that other aspects of psychological functioning, including state affect or mental health [29], may be more vulnerable to the impact of COVID-19 (but see [30]).

The present study had several strengths, including a pre-post design that captured trait psychological function just prior and during the acute phase of the coronavirus pandemic in the United States. The findings, however, need to be put in context. Although there was evidence of change, for example, the magnitude of change was small; in most cases, the change was less than one-tenth of a standard deviation. As such, overall there is more evidence of stability than substantial change. Still, personality would not be expected to change at all over such a short period of time in normal circumstances. The findings also need to be put in context of some limitations. First, the attrition analysis indicated that there were significant selection effects for who remained in the sample at Time 2 that may have had an effect on the results, particularly for Neuroticism (as discussed above). It is important to note that this study was not originally designed to be longitudinal, so participants in the pretest survey did not know that they would be asked to complete a second survey. With the pandemic, the study was reconceptualized to take advantage of the data collected on psychological functioning just prior to the pandemic. Fortunately, many participants were willing to fill out a second survey, but given that the original study was not meant to be longitudinal, there was no expectation that participants would continue to participate. Second, we tested for trait change in the acute phase of the pandemic. Although the purpose of this measurement was to address whether trait psychological functioning was responsive to an acute health-threatening crisis, it is also possible that the effects of the crisis could take longer to consolidate into substantial changes in personality. Future work will need to address whether there are long-term changes in personality in response to the coronavirus pandemic. Future work also needs to address personality change during the pandemic in other cultural contexts. Third, our measure of quarantine/isolation was broad and did not differentiate between quarantine or isolation and the situation for the participant during quarantine/isolation (e.g., whether the person was alone or with another person). As such, we could not disentangle the exact circumstance of the quarantine/isolation and whether such differences are important for personality change. Finally, as with all non-experimental research, there may be other explanations for the current set of results that we cannot rule out.

Overall, the results suggest more trait psychological resilience than harm during the acute phase of the coronavirus spread and response in the United States. Consistent with the notion that traits are stable and resistant to change, there were few changes in response to the spread of the coronavirus and the measures to control the spread in the United States. The results further suggest that the broader social environment may be modifying both how individuals see themselves (e.g., attributing less anxiety and depressed affect to themselves) and the meaning of specific items to how they measure a trait (e.g., items of Dutifulness). Future work will need to address whether these modest changes are long lasting and/or whether different patterns of change emerge if this crisis is protracted.

Pigeons try to overthrow a stable social order's hierarchy just adding weights to the revolutionaries' bodies; mass loading causes the low-ranked male birds to immediately become more aggressive and rise-up the dominance hierarchy

Artificial mass loading disrupts stable social order in pigeon dominance hierarchies. Steven J. Portugal, James R. Usherwood, Craig R. White, Daniel W. E. Sankey and Alan M. Wilson. Biology Letters, August 5 2020. https://doi.org/10.1098/rsbl.2020.0468

Abstract: Dominance hierarchies confer benefits to group members by decreasing the incidences of physical conflict, but may result in certain lower ranked individuals consistently missing out on access to resources. Here, we report a linear dominance hierarchy remaining stable over time in a closed population of birds. We show that this stability can be disrupted, however, by the artificial mass loading of birds that typically comprise the bottom 50% of the hierarchy. Mass loading causes these low-ranked birds to immediately become more aggressive and rise-up the dominance hierarchy; however, this effect was only evident in males and was absent in females. Removal of the artificial mass causes the hierarchy to return to its previous structure. This interruption of a stable hierarchy implies a strong direct link between body mass and social behaviour and suggests that an individual's personality can be altered by the artificial manipulation of body mass.

4. Discussion

Over a 31-month period, the dominance hierarchy of the pigeon group did not significantly change, with individuals retaining their position within the hierarchy throughout the experimental period. Previously, it has been demonstrated that in animal groupings of less than approximately 10 individuals, stable hierarchies are more commonly observed than in larger groups [27]. The linear dominance hierarchy in the pigeons was significantly related to body mass. There is no clear pattern yet determined as to why body mass is such a strong determinant of dominance in some species but not others [11,28]. It is possible that body mass is significantly correlated with dominance in species where secondary-sexual ornamentations are less pronounced, and as a result, signalling is less clear. In such cases, body mass may become more of an important indicator of fitness. The hierarchy returning to its stable structure upon the removal of the additional mass load suggests that no carry-over or ‘memory' effects of mass loading persist and implies an instantaneous neurological feedback mechanism regarding changes in body mass (e.g. [29]).

It is possible that the addition of the extra mass to the backs of the subordinate birds aggravated or stressed the birds, causing them to exhibit higher levels of aggression. During the addition of the artificial mass, the subordinate birds did not show any obvious signs of aggravation at the lead weights attached to them, nor did they try to peck or remove them, either on themselves or on conspecifics (S.J.P. personal observation), suggesting this is an unlikely explanation for their increased aggression. Similarly, the composition of aggressive behaviours did not change between weighted and unweighted sessions, suggesting behaviours were not more focused on the back, where the weights were attached. An alternative explanation, however, is that the addition of artificial mass—although only for a short period—increased the energetic requirements of the weighted birds, thus requiring them to be more aggressive to ensure adequate access to food [30,31]. Such a theory is akin to ‘lead according to need', an idea which has previously linked to motivation and leadership in group behaviour [32].

Only males responded to the artificial mass loading by significantly increasing their aggressive behaviour, while females did not seemingly respond, suggesting that increasing aggression in response to artificial mass loading is sex specific. Previously, it has been demonstrated that injections of testosterone into male pigeons did not make male pigeons more aggressive or dominant, [33], yet a perceived possible increase in physiological condition through the addition of mass in the present study did elicit a response. This sex-specific response may be linked to competition for females, with female pigeons preferentially selecting males for partnering who hold dominant positions within a hierarchy [34]. An avenue worthy of further investigation is the impact that the pairing status of an individual has on their respective rank, as it has been previously demonstrated in birds that being paired increases your rank within a hierarchy [35,36].

The present study demonstrates the plasticity of aggressive traits, and the rapidity with which they can be modified based on physiological condition. Fruitful future investigations would be to ascertain the attributes that lead to greater body masses in wild-type scenarios and in turn greater dominance. The ‘prior attributes' hypothesis [8,27,28], for example, suggests hierarchies are predetermined by personality or physiological differences in dominance ability. This in turn may be linked to leadership during flocking and associated energy expenditure [37–40]. How natural seasonal variations in body mass [41–43] manifest in terms of dominance and general social behaviour would further explore the interactions between individual physiology, energetics and social behaviour. Moreover, experiments that supplementary feed specific individuals over a longer period of time to increase body mass may yield different results with respect to the changes in their respective ranks. Our study focused on only one flock of birds, and to determine the full nature of these instantaneous changes in body mass, further studies are needed with larger sample sizes, both in terms of number of flocks and sampling sessions where mass was added, and ideally additional species.

Consistent with the proposition that people need to exert autonomy over their decisions, prosocial behavior is most likely to lead to happiness when actors have chosen to provide help

Helping and Happiness: A Review and Guide for Public Policy. Lara B. Aknin  Ashley V. Whillans. Social Issues and Policy Review, August 6 2020. https://doi.org/10.1111/sipr.12069

Abstract: Perhaps one of the most reaffirming findings to emerge over the past several decades is that humans not only engage in generous behavior, they also appear to experience pleasure from doing so. Yet not all acts of helping lead to greater happiness. Here, we review the growing body of evidence showing that people engage in a wide array of prosocial behaviors (e.g., charitable giving, volunteering, blood/organ donation, offering advice, food sharing) which can promote positive emotions. Then, using self‐determination theory, a foundational theory of human motivation, we consider when and how generous actions are most likely to boost the helper's happiness—and when they are not. Finally, we leverage these insights to consider how public policy and organizations can apply this information to make prosocial action more emotionally rewarding for citizens and employees alike.

Rather than the crisis fundamentally changing people psychologically, genetic differences between individuals seem to play a fundamental role in shaping psychological & behavioural responses to the COVID-19 crisis

Genetic correlates of psychological responses to the COVID-19 crisis in young adult twins in Great Britain. Kaili Rimfeld et al. Aug 2020. https://doi.org/10.21203/rs.3.rs-31853/v1

Abstract: We investigated how the COVID-19 crisis and the extraordinary experience of lockdown affected young adults in England and Wales psychologically. One month after lockdown commenced (T2), we assessed 30 psychological and behavioural traits in 4,000 twins in their mid-twenties and compared their responses to the same traits assessed in 2018 (T1). Mean changes from T1 to T2 were modest and inconsistent: just as many changes were in a positive as negative direction. Twin analyses revealed that genetics accounted for about half of the reliable variance at T1 and T2. Genetic factors correlated on average .86 between T1 and T2 and accounted for over half of the phenotypic stability. Systematic environmental influences had negligible impact on T1, T2 or T2 change. Rather than the crisis fundamentally changing people psychologically, our results suggest that genetic differences between individuals play a fundamental role in shaping psychological and behavioural responses to the COVID-19 crisis.

Keywords: COVID-19, lockdown, psychological and behavioural traits, twins, young adults, England and Wales


Discussion

How much has the COVID-19 crisis changed young adults psychologically following the unprecedented social experiment of one month of lockdown? As expected, the 30 measures in our study yielded many statistically significant changes in means. The largest changes in the negative direction were reduced volunteering and achievement motivation and increased hyperactivity-inattention. However, there were as many changes in the positive direction, most notably, reduced verbal peer victimisation. Changes were similar in direction and magnitude for males and females, with the single exception of general anxiety, which increased more for females than males. However, most of these mean changes have modest effect sizes, with an average d of 0.24. Although we expected that the crisis would affect some individuals more than others, we found no increase in variance at T2.  It is possible that the effects of the crisis will hit harder later or that longer lockdown or the economic aftermath of the crisis will have a greater effect. We will investigate these possibilities with three follow-up surveys during 2020.

Why do these young adults in Great Britain show modest negative effect on average after being in lockdown for one month when it is generally assumed that the psychological effects will be substantial? Part of the answer is that research often focuses on statistical significance and mean differences rather than considering effect size and individual differences. With our large sample size, nearly all variables show significant mean differences, but they don’t make much of a difference, accounting for less than two percent of the variance on average. Another reason might be methodological. In the present study we did not focus on participants’ subjective reports of how the COVID-19 crisis changed them. Instead, at T2, we asked participants to report, for example, how depressed they felt during the month following lockdown, which we compared to their reports of depression on the same measures in 2018. We found no difference in depression on average.

Other reasons why we found few negative effects of the COVID-19 crisis could be that the lockdown was so widespread (we’re all in it together spirit?) or that our participants are British (stiff upper lip?) or that they are young adults (resilience? insouciance?). Concerning the insouciance hypothesis, we asked participants at T2 how much they were worried about their physical health and mental health during the month since lockdown. The frequency of those reporting that they were moderately, very, or extremely worried was 38% for physical health and 57% for mental health. In other words, they were, quite reasonably, worried, although on average they did not change psychologically, including their symptoms of general anxiety. This can be viewed as a hopeful message that young people on average, are resilient psychologically to an experience as seismic as COVID-19 and lockdown, although these mean differences mask individual differences to the COVID-19 and lockdown. It remains to be seen if similar results emerge in other countries, at other ages and after longer exposure to the crisis and its aftermath.

The focus of our study was on individual differences rather than mean differences. How much has COVID-19 shuffled the deck of individual differences? The rank order of individual differences was largely stable from T1 to T2, with stability accounting for about 70% of the reliable variance at T1 and T2 on average across the measures. From a genetic perspective, the most interesting finding was that the average genetic correlation was 0.86, indicating that genetic effects at T1 were highly correlated with genetic effects at T2, despite the intervening COVID-19 crisis and lockdown. It is also interesting that T2 changes, which are independent of T1, show genetic influence.

We conclude that inherited DNA differences are the major systematic force shaping individual differences in psychological traits at T2 as well as at T1. Genetic effects account for about half of the reliable psychological differences between people at T1 and T2. The environment accounts for the rest of the variance, but it is not the systematic effect of environmental factors often assumed to be important, such as shared family environment. Environmental factors of this systematic sort had negligible effects on variance at T1 and T2 and for T2 change. The environmental effects that make a difference are those that are not shared by twin siblings growing up in the same family or, in our study, by twins locked down together. These idiosyncratic ‘non-shared’ environmental factors are likely to be unsystematic, chance experiences (Plomin, 2018).

Our results confirmed seven of our eight pre-registered (https://osf.io/r58be/) hypotheses. This speaks to the replicability of findings from behavioural genetic research on which these hypotheses were based, which is noteworthy given the replication crisis in science in general and in psychology in particular (Plomin et al., 2016). The exception was the hypothesis that variance at T2 would be greater than at T1, which was a prediction not based on behavioural genetic research. The consistency of results from T1 to T2 also attests to the replicability of research in behavioural genetics.

Concluding that inherited DNA differences are the major systematic force shaping who we are psychologically does not imply that novel environmental interventions, including therapeutic interventions, cannot make a difference. It should be emphasised that heritability does not imply immutability.

Heritability is a descriptive statistic limited to a particular population at a particular time with a particular mix of genetic and environmental influences. Our study can be seen as an attempt to assess whether heritability changed as a function of a tectonic shift in environment, the COVID-19 crisis.

Concluding that the COVID-19 crisis has not fundamentally changed these young people psychologically is not to dismiss the pain some of them felt before or during the crisis, or will continue to feel after the crisis ends. Even though the crisis had little effect on means and even less effect on variances and covariances, genetically driven psychological vulnerabilities are especially important targets for preventive interventions in young adults because the twenties is a pluripotent tipping point for life-long psychological problems (Arnett, 2014; Smith et al., 2011).

Imagining the future, remembering the past: Future events were simulated at proportionally higher speed than past events; the density of experience units representing the unfolding of events was lower for future episodes

The temporal compression of events during episodic future thinking. Olivier Jeunehomme, Nathan Leroy, Arnaud D'Argembeau. Cognition, August 6 2020, 104416. https://doi.org/10.1016/j.cognition.2020.104416

Highlights
• The unfolding of real-world events is temporally compressed in future simulations.
• Compression rates are higher for future than past events.
• Compression rates are lower for actions than spatial displacements.
• Temporal compression depends on the density of represented experience units.
• Experience units serve as an index for estimating past and future event durations.

Abstract: While the cognitive and neural mechanisms that underlie episodic future thinking are increasingly well understood, little is known about how the temporal unfolding of events is represented in future simulations. In this study, we leveraged wearable camera technology to examine whether real-world events are structured and compressed in the same way when imagining the future as when remembering the past. We found that future events were simulated at proportionally higher speed than past events and that the density of experience units representing the unfolding of events was lower for future than for past episodes. Despite these differences, the nature of events influenced compression rates in the same way for past and future events. Furthermore, the perceived duration of both types of events depended on the density of represented experience units. These results provide novel insight into the mechanisms that structure the unfolding of events during future simulations.

Keywords: Episodic memoryEpisodic future thinkingTemporal compressionTime estimationWearable camera

Trait mindfulness do not reliably translate into a pattern of healthful behaviours in general, although trait mindfulness shows a stronger associations with health behaviours under certain conditions

Trait mindfulness and health behaviours: a meta-analysis. Margarita Sala ,Catherine Rochefort,P. Priscilla Lui &Austin S. Baldwin. Health Psychology Review, Volume 14, 2020 - Issue 3, Pages 345-393, Aug 11 2019. https://doi.org/10.1080/17437199.2019.1650290

ABSTRACT: Mindfulness is defined as bringing one’s attention to present-moment experience with acceptance, and is associated with engagement in various health behaviours. To synthesise and evaluate this literature, we conducted a comprehensive meta-analytic review and examined (a) the associations between trait mindfulness and health behaviours and (b) the extent to which these associations were moderated by study and individual differences. A total of 125 independent samples were included (N = 31,697, median male percentage = 38.8%, median age = 28.3). A multilevel random-effects model was used to estimate summary study-level effect sizes, and multilevel mixed-effects models were used to examine moderator effects. Mindfulness had a positive and small association with aggregated health behaviours (r = .08). Mindfulness was positively associated with physical activity, healthy eating, and sleep (rs = .08–.14), and negatively associated with alcohol use (r = −.06). Effects were larger for health promoting behaviours, the acting with awareness facet of mindfulness, and samples involving psychiatric patients. Although findings indicate that individual differences in trait mindfulness do not reliably translate into a pattern of healthful behaviours in general, trait mindfulness shows a stronger associations with health behaviours under certain conditions.

KEYWORDS: Mindfulness, physical activity, healthy eating, sleep, substance use

Increasing Population Densities Predict Decreasing Fertility Rates over Time: A 174-nation Investigation

Rotella, Amanda M., Michael E. W. Varnum, PhD, Oliver Sng, and Igor Grossmann. 2020. “Increasing Population Densities Predict Decreasing Fertility Rates over Time: A 174-nation Investigation.” PsyArXiv. August 5. doi:10.31234/osf.io/zpc7t

Abstract: Fertility rates have been declining worldwide over the past five centuries, part of a phenomenon known as “the demographic transition”. Prior work suggests that this decline is related to population density, however to date this work has either been largely atheoretical or cross sectional. We draw on life history theory to examine the relationship between population density and fertility over time both within and between countries across 174 countries over 69 years (1950 to 2019) using annual data. Using state-of-the-art methods, we find a robust relationship between density and fertility; increased population densities are associated with lower fertility rates, controlling for a variety of socioeconomic, socioecological, geographic, cultural, population-based, and female empowerment related variables. Importantly, we also generate predictions about the conditions in which this effect should be stronger vs. weaker. Consistent with these predictions, we find that where conditions are harsh and favor engagement in shorter-term strategies (i.e., high homicide rates, low GDP per capita, high economic inequality, and high pathogen prevalence), the effect of increased population density on fertility rates is attenuated. We also find that the density-fertility relationship is moderated by religiousness and strength of social norms. These findings shed new light on why, and under what conditions, rising population densities influence fertility rates.

Intelligence manifests itself in the brain in breaking a problem down into multiple subtasks, which are worked on in widely distributed processing units, showing signs of being focused on the common plan

Integrated Intelligence from Distributed Brain Activity. John Duncan, Moataz Assem, Sneha Shashidhara. Trends in Cognitive Sciences, August 5 2020. https://doi.org/10.1016/j.tics.2020.06.012

Highlights
.  Fluid intelligence tests predict success in many activities, suggesting cognitive mechanisms of broad importance.
.  We propose a core process of attentional integration. Complex problems must be segmented into simpler parts. Attention to each part integrates cognitive fragments into a computational structure.
.  Fluid intelligence is linked to the brain’s multiple-demand (MD) system, defined by common activity across different cognitive demands. Across the brain, MD patches shows anatomical and physiological properties adapted to attentional integration.
.  Neurophysiology of putative MD regions shows adaptive coding of task-relevant information. Suiting attentional integration, many neurons show conjunctive coding (e.g., binding cognitive operations to their target objects).
.  In broad outline, these results suggest how distributed brain activity builds organized cognition.

Abstract: How does organized cognition arise from distributed brain activity? Recent analyses of fluid intelligence suggest a core process of cognitive focus and integration, organizing the components of a cognitive operation into the required computational structure. A cortical ‘multiple-demand’ (MD) system is closely linked to fluid intelligence, and recent imaging data define nine specific MD patches distributed across frontal, parietal, and occipitotemporal cortex. Wide cortical distribution, relative functional specialization, and strong connectivity suggest a basis for cognitive integration, matching electrophysiological evidence for binding of cognitive operations to their contents. Though still only in broad outline, these data suggest how distributed brain activity can build complex, organized cognition.

Keywords: intelligenceattentioncognitive controlbrain networksneural coding

Concluding Remarks and Future Directions

Many issues are raised by the integration account. Here we discuss two: the interface of short-term cognitive activity and long-term knowledge, and the nature of attentional capacity limitations.

As implied by our discussion of positive manifold, a core question is interface between on-line cognition and long-term knowledge. As in classical symbolic artificial intelligence (e.g., [97]), a complex problem is divided into simple parts on the basis of long-term knowledge of the structure of the world and relations within it. It is knowledge that tells us how travel to Japan can be divided into component steps, how a useful move can be made in proving a mathematical theorem, or where we should look in seeking a solution to a spatial puzzle. In the brain, knowledge that might shape current cognition is distributed across multiple brain systems. Semantic memory, for example, may be based around a proposed hub in the temporal pole [98], while episodic memory, spatial knowledge, and social knowledge are linked to distinct components of the default mode network [99]. To understand MD activity in constructing solutions to cognitive problems, we need to know how multiple aspects of knowledge feed into this process. Again, this is reminiscent of the widespread connectivity of MD regions (Figure 5) and our finding that multiple networks have representatives in the MD penumbra.

In classical artificial intelligence, problem solutions were often built up in an unlimited working memory, keeping track of a progressively more complex structure of goals and subgoals. For biological cognition this is not plausible; for goals such as travel to Japan or solving a scientific problem, only a small fraction can be represented in active neural firing at any one time, with the rest of the structure in long-term memory, ready for retrieval when required. At the same time, the current active focus of attention must remain bound to the long-term structure, so that, for example, a failure to progress to a goal by one route can trigger a search for an alternative. The issue is reminiscent of recent biological accounts of working memory, combining active neural firing with storage through short-term synaptic change [100,101]. It is presently unknown how the focus of attention in active cognition can be situated within a complex, long-term representation of the larger-scale problem.

A further open issue concerns the well-known capacity limitations of ‘attention’, reflected in difficulty carrying out several tasks at once [102,103]. Shared demands on MD activity could provide an obvious basis for such limits and, indeed, various authors have linked capacity limitations to the functions of frontal and parietal cortex [16,22,104,105]. Such proposals find support in neurophysiological studies, showing that, in frontal and parietal cortex, there is interference between representations of different visual stimuli [106], working memory items [107], or task components [86,108]. Further work is needed, however, to understand the physiological basis of this interference. In the visual system, capacity limits in representing multiple stimuli are thought to arise through a process of competition or divisive normalization [109., 110., 111.]. In such models, each stimulus attempts to drive the activity of a neuron to a particular value, appropriate to representing the properties of this stimulus; with multiple stimuli in the field, opposing forces bring activity to a compromise value, reducing the fidelity of representation for any one. Similar patterns can be seen in the visual responses of prefrontal neurons [112,113], raising the possibility that divisive normalization is a general principle in MD cortex. Recurrent neural networks have become popular as models of working memory and cognitive control (e.g., [114]), and in a recent model, divisive normalization is the basis for limited working memory capacity [115]. Further experimental work is needed to test whether divisive normalization models may be extended to the broader attentional limits of MD activity and cognitive control.

Of course, our account of cognitive integration leaves much unknown. That said, like an early map of the globe, it provides an outline sketch of how distributed brain activity can assemble complex cognition. This sketch, we suggest, provides the skeleton we need to guide future, more detailed physiological study (see Outstanding Questions).

Outstanding Questions

How do different MD regions interact? Across the extended MD system, we know little of the dynamics of information representation and exchange during task performance. The very different connectivities of MD regions imply separate functional contributions to cognitive integration, but in fMRI, the dominant picture is one of corecruitment. This picture may reflect the low temporal resolution of fMRI, rendering the method blind to high-speed information development and exchange. Elucidating how task-relevant information arises and is distributed across the network calls for simultaneous electrophysiological recordings in separate MD regions, either in experimental animals or patients implanted for intracranial recordings.

How does MD activity bind together coherent processing across multiple brain regions? Again, this calls for electrophysiological studies, addressing questions that include directional information flow at different stages of a cognitive operation, and the role of precise timing relations (e.g., oscillatory synchrony) across brain regions.

How are brief segments of cognition combined into complex goal–subgoal structures? For example, we know little of how sustained goal maintenance directs brain activity in pursuit of a series of subgoals. Especially for complex behavior, a critical question is interaction between immediate cognitive activity and long-term knowledge of goals, subgoals, and their relationships.

What is the role of prominent MD foci seen outside cerebral cortex, especially in caudate and cerebellum? Almost nothing is known of cortical-subcortical and cerebro-cerebellar interaction as cognitive operations are carried out. High-field imaging may bring the spatial resolution needed for studies of small subcortical structures.

Creative behaviors seem to yield survival & reproductive benefits; however, individuals often have to violate social norms; this deviance entails consequences detrimental for both survival and reproduction

The paradox of creativity. Eric Bonetto et al. New Ideas in Psychology, Volume 60, January 2021, 100820. https://doi.org/10.1016/j.newideapsych.2020.100820

Highlights
• Creative behaviors seem to yield survival and reproductive benefits.
• However, to be creative, individuals often have to violate social norms.
• This deviance entails consequences detrimental for both survival and reproduction.
• We propose to call this paradox the paradox of creativity.

Abstract: Creativity seems to yield survival and reproductive benefits. Creative behaviors allow individuals to solve problems in new and appropriate ways, and thus to promote their survival. They also facilitate bonding and constitute a signal of one's fitness, favoring attraction of mates. However, to be creative, individuals often have to violate social norms in order to promote change. So far, this deviance induced by creative behaviors had not been seen as an adaptive disadvantage. This deviance entails negative consequences as social exclusion or ostracism, which are detrimental for both survival (e.g., reduced access to resources within the group) and reproduction (reduced reproductive fitness). Thus, the adaptive benefits yielded by creativity have to be nuanced by these potential disadvantages. The paradox of creativity proposes a finer-grained vision of the adaptive reasons why creativity has been maintained within the human species, has evolved, and is collectively regulated. Research perspectives are also proposed.

Keywords: Evolutionary perspectiveCreativityParadox of creativity

From 2012... Comparative Environmental Life Cycle Assessment of Conventional and Electric Vehicles

From 2012... Comparative Environmental Life Cycle Assessment of Conventional and Electric Vehicles. Troy R. Hawkins, Bhawna Singh, Guillaume Majeau-Bettez, and Anders Hammer Strømman. Journal of Industrial Ecology, Volume 17, Number 1, Oct 12 2012. https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1530-9290.2012.00532.x

Summary: Electric vehicles (EVs) coupled with low-carbon electricity sources offer the potential for reducing greenhouse gas emissions and exposure to tailpipe emissions from personal transportation. In considering these benefits, it is impor tant to address concerns of problem-shifting. In addition, while many studies have focused on the use phase in comparing transportation options, vehicle production is also significant when comparing conventional and EVs. We develop and provide a transparent life cycle inventory of conventional and electric vehicles and apply our inventory to assess conventional and EVs over a range of impact categories. We find that EVs powered by the present European electricity mix offer a 10% to 24% decrease in global warming potential (GWP) relative to conventional diesel or gasoline vehicles assuming lifetimes of 150,000 km. However, EVs exhibit the potential for significant increases in human toxicity, freshwater eco-toxicity, freshwater eutrophication, and metal depletion impacts, largely emanating from the vehicle supply chain. Results are sensitive to assumptions regarding electricity source, use phase energy consumption, vehicle lifetime, and battery replacement schedules. Because production impacts are more significant for EVs than conventional vehicles, assuming a vehicle lifetime of 200,000 km exaggerates the GWP benefits of EVs to 27% to 29% relative to gasoline vehicles or 17% to 20% relative to diesel. An assumption of 100,000 km decreases the benefit of EVs to 9% to 14% with respect to gasoline vehicles and results in impacts indistinguishable from those of a diesel vehicle. Improving the environmental profile of EVs requires engagement around reducing vehicle production supply chain impacts and promoting clean electricity sources in decision making regarding electricity infrastructure.

Keywords: batteries, electricity mix, global warming, industrial ecology, life cycle inventory (LCI), transportation

Check also China’s booming electric vehicle market is about to run into a mountain of battery waste. By Echo Huang. Quartz, September 28, 2017. http://www.bipartisanalliance.com/2017/10/chinas-booming-electric-vehicle-market_14.html

And How many electric vehicles can the current Australian electricity grid support?, Li and Lenzen, International Journal of Electrical Power & Energy Systems, Volume 117, May 2020. https://www.bipartisanalliance.com/2020/01/how-many-electric-vehicles-can-current.html

And Leading scientists set out resource challenge of meeting net zero emissions in the UK by 2050. National History Museum, Jun 5 2019. https://www.bipartisanalliance.com/2019/06/to-replace-all-uk-based-vehicles-today.html:

my summary: To replace all UK-based vehicles today with electric vehicles would take near 2 times the total annual world cobalt production, nearly the world's neodymium & dysprosium, 3/4 the world’s lithium & at least 1/2 the world’s copper in 2018 

Also: "The worldwide impact: If this analysis is extrapolated to the currently projected estimate of two billion cars worldwide, based on 2018 figures, annual production would have to increase for neodymium and dysprosium by 70%, copper output would need to more than double and cobalt output would need to increase at least three and a half times for the entire period from now until 2050 to satisfy the demand."

How much are electric vehicles driven? Lucas W. Davis. Applied Economics Letters, Feb 20 2019. https://www.bipartisanalliance.com/2019/02/the-prospect-for-electric-vehicles-as.html

The incidence rate of dementia in Europe and North America has declined by 13% per decade over the past 25 years, consistently across studies; incidence is similar for men and women

Twenty-seven-year time trends in dementia incidence in Europe and the United States. The Alzheimer Cohorts Consortium, Frank J. Wolters et al. Neurology, August 04, 2020; 95 (5). https://doi.org/10.1212/WNL.0000000000010022

Abstract
Objective To determine changes in the incidence of dementia between 1988 and 2015.

Methods This analysis was performed in aggregated data from individuals >65 years of age in 7 population-based cohort studies in the United States and Europe from the Alzheimer Cohort Consortium. First, we calculated age- and sex-specific incidence rates for all-cause dementia, and then defined nonoverlapping 5-year epochs within each study to determine trends in incidence. Estimates of change per 10-year interval were pooled and results are presented combined and stratified by sex.

Results Of 49,202 individuals, 4,253 (8.6%) developed dementia. The incidence rate of dementia increased with age, similarly for women and men, ranging from about 4 per 1,000 person-years in individuals aged 65–69 years to 65 per 1,000 person-years for those aged 85–89 years. The incidence rate of dementia declined by 13% per calendar decade (95% confidence interval [CI], 7%–19%), consistently across studies, and somewhat more pronouncedly in men than in women (24% [95% CI 14%–32%] vs 8% [0%–15%]).

Conclusion The incidence rate of dementia in Europe and North America has declined by 13% per decade over the past 25 years, consistently across studies. Incidence is similar for men and women, although declines were somewhat more profound in men. These observations call for sustained efforts to finding the causes for this decline, as well as determining their validity in geographically and ethnically diverse populations.

The Origin of Our Modern Concept of Depression—The History of Melancholia From 1780-1880

The Origin of Our Modern Concept of Depression—The History of Melancholia From 1780-1880: A Review. Kenneth S. Kendler.
JAMA Psychiatry. 2020;77(8):863-868. doi:10.1001/jamapsychiatry.2019.4709

Abstract: The modern concept of depression arose from earlier diagnostic formulations of melancholia over the hundred years from the 1780s to the 1880s. In this historical sketch, this evolution is traced from the writings of 12 authors outlining the central roles played by the concepts of faculty psychology and understandability. Five of the authors, writing from 1780 through the 1830s, including Cullen, Pinel, and Esquirol, defined melancholia as a disorder of intellect or judgment, a “partial insanity” often, but not always, associated with sadness. Two texts from the 1850s by Guislain, and Bucknill and Tuke were at the transition between paradigms. Both emphasized a neglected disorder—melancholia without delusions—arguing that it reflected a primary disorder of mood—not of intellect. In the final phase in the 1860s to 1880s, 5 authors (Griesinger, Sankey, Maudsley, Krafft-Ebing, and Kraepelin) all confronted the problem of the cause of delusional melancholia. Each author concluded that melancholia was a primary mood disorder and argued that the delusions emerged understandably from the abnormal mood. In this 100-year period, the explanation of delusional melancholia in faculty psychology terms reversed itself from an intellect to mood to a mood to intellect model. The great nosologists of the 19th century are often seen as creating our psychiatric disorders using a simple inductive process, clustering the symptoms, signs, and later the course of the patients. This history suggests 2 complexities to this narrative. First, in addition to bottom-up clinical studies, these nosologists were working top-down from theories of faculty psychology proposed by 18th century philosophers. Second, for patient groups experiencing disorders of multiple faculties, the nosologists used judgments about understandability to assign primary causal roles. This historical model suggests that the pathway from patient observation to the nosologic categories—the conceptual birth of our diagnostic categories—has been more complex than is often realized.

Introduction
Before the rise of modern psychiatry in the late 18th century, the concept of melancholia differed substantially from our modern view of depression,1-6 which did not emerge until the late 19th century.1,2,7,8 By examining key texts published from 1780 to 1880, I document the nature and timing of this shift through 3 phases. Two theories play important roles in this story: faculty psychology9-13 and understandability.13-16 Faculty psychology is defined as

The theory, in vogue particularly during the second half of the eighteenth and first half of the nineteenth centuries, that the mind is divided up into separate inherent powers or “faculties.”17(p253)

I focus on 2 of these inborn faculties, one predominant at the initiation of this story (intellect, understanding, or judgment), and the other whose rising influence I track across the 19th century: mood, affect, or moral (ie, psychological) sentiment.

Given the frequency of patients apparently experiencing disorders both of intellect and mood, the theory of faculty psychology posed a problem. To give a proper diagnosis, clinicians needed to distinguish between 3 hypotheses about such patients. Did they have 2 independent disorders, a primary disorder of intellect with a secondary mood disorder or a primary disorder of mood with a secondary disorder of intellect?13 A dominant approach to this problem, later popularized by Karl Jaspers,14,15 was that with careful observation and empathy, the clinician could discriminate between these hypotheses, for example, determining if a delusion (a disorder of intellect) could arise understandably from a disordered mood.

Phase 1: 1780-1830
In the first historical phase, all major authors emphasized that melancholia was primarily a disorder of intellect, often—but not always—accompanied by sadness.

I begin with the medical nosology of William Cullen (1710-1790), a physician and leading figure in the Scottish enlightenment. In his highly influential 1780 nosology,18,19 melancholia was placed within the class of neuroses (nervous disorders), and the order of vésanie (mental diseases/insanity) characterized as “a disorder of the functions of the judging faculty of the mind, without fever or sleepiness.”19 Melancholia was defined as “partial insanity without dyspepsia,” with the phrase “without dyspepsia” included to distinguish it from hypochondriasis. By partial insanity, Cullen meant that the delusions were limited to a single subject, leaving the affected individual with intact areas of intellectual functioning.

Phillipe Pinel (1745-1826),20,21 a major reformer and one of the founders of modern psychiatry, provided the following definition of melancholia in 1801:

Delirium (ie, delusions) exclusively upon one subject … free exercise in other respects of all the faculties of the understanding: in some cases, equanimity of disposition, or a state of unruffled satisfaction: in others, habitual depression and anxiety, and frequently a moroseness of character … and sometimes to an invincible disgust with life.21(p149)

Like Cullen,18,19 Pinel’s definition emphasized intellectual dysfunction (eg, partial insanity), but he added a range of associated mood states. Some of the states reflect depression but another described emotional equanimity.

In his 1804 treatise on madness and suicide,”22 the English physician William Rowley (1742-1806) gave a succinct definition of melancholia that agrees in essential points with his predecessors, with the disordered intellect here termed “alienation of the mind”:

Madness, or insanity, is an alienation of the mind, without fever. It is distinguished into two species; melancholy, or mania…. The former is known by sullenness, taciturnity, meditation, dreadful apprehensions, and despair.22(p1)

Rowley differs from his predecessors in associating melancholia only with the moods of sadness and anxiety.

In his 1817 monograph on melancholia,23 Maurice Roubaud-Luce’s description of melancholia resembled that of his French predecessor, Pinel,20,21 including its possible association with elevated mood states:

Melancholy is characterized by an exclusive and chronic delirium focused on a single object, or on a particular series of objects, with a free exercise of intellectual faculties on everything that is foreign to these objects. This condition is often accompanied by a deeply concentrated sadness, a state of dejection and stupor, and an ardent love of solitude. Sometimes also it excites, for no apparent reason, immoderate joy…. 23(p1)

Jean Esquirol (1772-1840), Pinel’s student and successor as leader of French psychiatry, coined the term lypemania as a synonym for melancholia.24,25 Like Rowley, in his 1838 textbook, he removed the association with mania-like partial insanities:

We consider it well defined, by saying that melancholy … or lypemania, is a cerebral malady, characterized by partial, chronic delirium, without fever, and sustained by a passion of a sad, debilitating or oppressive character.25(p203)

Phase 2: 1850-1860
In phase 2, the dominant view of melancholia as a primary disorder of intellect came under challenge.

Joseph Guislain (1789-1860), a Belgian alienist and director of the psychiatric hospital at Ghent, took a first step toward the modern view of depression. He described, in his 1852 text,26 6 elementary forms of mental maladies, one of which was mélancolie, defined as “mental pain—augmentation of sentiments of sadness.26(p94) He then described the relatively novel category of nondelusional melancholia, calling it

exclusively an exaggeration of affective feelings; it is a pathological emotion, a sadness, a grief, an anxiety, a fear, a fright, and nothing more. It is not a state which appreciably weakens conceptual faculties.26(p112)

He continues:

The description that the [prior] authors gave us of this disease [melancholy] leaves something to be desired; almost all spoke of delusional melancholy, and none, to my knowledge, describes melancholy in its state of greatest simplicity: there are melancholies without delusions … without noticeable disturbance of intelligence or ideas. Melancholy without delusion is the simplest form under which the suffering mode can occur; it is a state of sadness, dejection … without notable aberration of imagination, judgement or intelligence … a despair dominates him; he is absorbed into this painful feeling.26(p186)

In their influential 1858 textbook, John Bucknill (1817-1897) and Daniel Tuke (1827-1895) took a further step away from the view of melancholia as primarily a disorder of intellect. In the section on melancholia, written by Tuke, he begins with the quotation above from Esquirol25 to which he adds a critical comment (italics added):

“We consider it well-defined,” he observes “by saying that melancholia or lypemania, is cerebral malady, characterized by partial chronic delirium, without fever, and sustained by a passion of a sad, debilitating, or oppressive character.” A definition sufficiently accurate, if we except the “chronic delirium,” disorder of the intellect not being, as we shall presently see, an essential part of the disorder.27(p152)

Tuke argues that delusions have been incorrectly understood as the primary melancholic symptom. Following Guislain,26 Tuke operationalizes this change by defining a simple form of melancholia in which “there is here no disorder of the intellect, strictly speaking; no delusion or hallucination.27(p158) Bucknill and Tuke are then more explicit about their new conceptualization of melancholia: “it can be shown that the disorder at present under consideration, may coexist with a sound condition of the purely intellectual part of our mental constitution.27(p159)

Tuke provides his rationale for this conceptual shift in his earlier chapter on classification. After reviewing prior nosologic systems, he writes of the importance of faculty psychology in psychiatric nosology: “The writer thinks there is much to be said in favor of the attempt to classify the various forms of insanity, according to the mental functions affected.”27(p95) He then quotes his coauthor, “Dr Bucknill observes that insanity may be either intellectual, emotional, or volitional.”27(p95) We cannot, he argues, base our nosology on the “physiology of the organ of the mind,” because we do not know it. But, he continues, “in the absence of this knowledge it would seem reasonable to adapt them to the affected function.”27(p95) We could then, he concludes, “speak of disorders of the intellect, sentiment, etc. instead of basing our classification exclusively on prominent symptoms.”27(p95) He formalizes the conclusion:

In bringing the phenomena of diseased mind into relation with such classification, we should endeavor to refer every form of disease to that class or group of the mental faculties which the disease necessarily, though not exclusively, involves in its course.27(p98)

In his ideal nosology, idiocy, dementia, and monomania, which commonly manifests delusions and hallucinations, are disorders of the intellect while melancholia is considered a disorder of “moral sentiment,” that is, mood.

Phase 3: 1860-1883
Phase 3 continues the shift from the view that melancholia was predominantly a disorder of intellect to one of mood. But these authors also confronted the problem of delusional melancholia. If it too is primarily a disorder of mood, how can the emergence of delusions be explained? Their response to this question will incorporate the concept of understandability.

The first professor of psychiatry in Germany and a strong advocate for a brain-based psychiatry, Wilhelm Griesinger (1817-1868), early in his 1861 textbook,28,29 adopts a faculty psychological approach to psychiatric nosology in his chapter entitled “The Elementary Disorders in Mental Disease”:

In those cerebral affections which come under consideration as mental diseases, there are, as in all others, only three essentially distinct groups…. Thus, according to this threefold division, we have to consider successively each of the three leading groups of elementary disturbances—intellectual insanity, emotional insanity, and insanity of movement.29(p60)

Although like Guislain26 before him, Griesinger viewed melancholia as typically forming the first stage of a unitary psychosis: both of their descriptions are of relevance. Griesinger begins, “The fundamental affection in all these forms of disease consists in the morbid influence of a painful depressing negative affection—in a mentally painful state.”29(p209) That is, he clearly emphasized the affective nature of the disorder. He elaborates:

In many cases, after a period of longer or shorter duration, a state of vague mental and bodily discomfort … a state of mental pain becomes always more dominant and persistent…. This is the essential mental disorder in melancholia, and, so far as the patient himself is concerned, the mental pain consists in a profound feeling of ill-being, of inability to do anything, of suppression of the physical powers, of depression and sadness…. The patient can no longer rejoice in anything, not even the most pleasing.29(p223)

Earlier in the book, Griesinger sought to explain how disordered mood can produce delusions.

As to their contents, two leading differences are particularly to be observed in insane conceptions [one of which is] … somber, sad, and painful thoughts …. [which arise] from depressed states of the disposition, and gloomy ill-boding hallucinations, as language of abuse and mockery which the patient is always hearing, diabolical grimaces which he sees, etc. The false ideas and conclusions, which are attempts at explanation and vindications of the actual disposition in its effects, are spontaneously developed in the diseased mind according to the law of causality…. At first the delirious conceptions are fleeting … gradually, by continued repetition, they gain more body and form, repel opposing ideas … then they become constituent parts [of the “I”] … and the patient cannot divest himself of them.29(p71)

Early in his 1866 text, William Sankey (1813-1889), an asylum director and lecturer at University College London, outlined morbid psychiatric conditions of the intellect, emotions, and volition. He turned to discussing the development of melancholia:

The alterations in degree are such as an increase of grief, a depression of spirits going on to melancholy…. Such description of abnormal acts of mind belong to the emotions, and occur in the earlier stages, the later or more permanent alterations of kind may be manifested in the (a) intellect, (b) the disposition, (c) the manner, (d) temper, (e) habits, and (f) character of the individual.30(p25)

Therefore, primary alterations in emotions can lead to a range of developments in melancholia, including alterations in intellectual functioning including “in power of judgment, apprehension, imagination, argumentation, memory, or they may entertain distinct illusion [hallucination] or delusion.”30(p25) He captures this point in a case history of melancholia which he summarizes:

The progress of this case was therefore—simple depression, abstraction, forgetfulness, neglect of duties… religious fears, and morbid apprehensions and delusions… You see how closely nearly all these symptoms are connected with the emotions. Fear, apprehension, and dread are among the commonest phenomena.30(p30)

Early in his section on the varieties of insanity from his 1867 textbook,31 Henry Maudsley (1835-1918) adopted a faculty psychological orientation:

On a general survey of the symptoms of these varieties it is at once apparent that they fall into two well-marked groups one of these embracing all those cases in which the mode of feeling or the affective life is chiefly or solely perverted—in which the whole habit or manner of feeling, the mode of affection of the individual by events, is entirely changed; the other, those cases in which ideational or intellectual derangement predominates.31(p301)

He then outlines how the effects of the mood disorder spread through other faculties:

Consequently, when there is perversion of the affective life, there will be morbid feeling and morbid action; the patient's whole manner of feeling, the mode of his affection by events, is unnatural, and the springs of his action are disordered; and the intellect is unable to check or control the morbid manifestations.31(p302)

He later continues:

The different forms of affective insanity have not been properly recognised and exactly studied because they did not fall under the time-honoured divisions and the real manner of commencement of intellectual insanity in a disturbance of the affective life has frequently been overlooked.31(p321)

Maudsley then attacks the earlier views of melancholia—that the intellectual dysfunctions were primary and the mood disorder secondary (italics added):

It is necessary to guard against the mistake of supposing the delusion to be the cause of the passion, whether painful or gay …. Suddenly, it may be, an idea springs up in his mind that he is lost forever, or that he must commit suicide, or that he has committed murder and is about to be hanged; the vast and formless feeling of profound misery has taken form as a concrete idea —in other words, has become condensed into a definite delusion, this now being the expression of it. The delusion is not the cause of the feeling of misery, but is engendered of it, it is precipitated, as it were in a mind saturated with the feeling of inexpressible woe.31(p328)

Richard von Krafft-Ebing (1840-1902), among the most important late 19th century German-speaking neuropsychiatrists,32,33 wrote in his influential 1874 monograph on melancholia, “The basic phenomenon in melancholic insanity is simply mental depression, psychic pain in its elementary manifestation.”34(p1) By analogy with a peripheral neuralgia, melancholia transforms normal psychological experiences into anguish and sorrow. Affected individuals have repeated “painful distortions” of their experiences, “all his relations to the external world are different … he is unfeeling, homeless ... with unbearable despair.”34(p5)

In his section on melancholy with delusions and hallucinations, Krafft-Ebing writes

Let us look at the sources of these [symptoms]. Initially it is the altered sense of self of the patient, the consciousness of deep abasement … the fractured strength and ability to work, which require an explanation and, with advancing disturbance of consciousness, does not find this in the subjective aspect of the illness, but in the delusional changes of relationship to the external world, from which we are after all used to receiving the impulses for our feelings, ideas and ambitions. This formation of delusions is supported significantly by the deep disturbance of the perception of the world.34(p32)

He then gives examples of how delusions of poverty, persecution, and impending punishment can emerge “in a psychological manner … from elementary disturbances of mood”34(p34):

Thus, deep depression of the sense of self, and the consciousness of mental impotence and physical inability to work, lead to the delusion of no longer being able to earn enough, of being impoverished, of starvation.34(p33)

Mental dysesthesia thus causes hostile apperception of the external world, as presumed suspicious glances, scornful gestures, abusive speeches from the environment join, leading to persecutory delusions…. Precordial anxiety and expectations of humiliation lead to the delusion that an actual danger is threatening [where] … a prior harmless action which is not even a crime … is formed into an actual crime.34(p34)

Emil Kraepelin’s views of melancholia, unencumbered by his later development of the category of manic-depressive illness, can be found in the first edition of his textbook published in 1883. He saw this syndrome as arising from “psychological anguish” when “the feelings of dissatisfaction, anxiety and general misery gains such strength that it constantly dominates the mood.”35(p190) He describes the emergence of depressive delusions:

… in milder cases … there is insight into his own illness. As a rule, however, critical ability becomes overwhelmed by powerful mood fluctuations, and the pathological change is transferred to the external world. It does not merely seem to be so dismal and bleak, but really is so. A further progression … can then give rise to formal delusions and a systematic distortion of external experiences.35(p191)

The writings of Krafft-Ebing32,33 and Kraepelin35 reflect a culmination in the development of the modern concept of depression, an illness resulting primarily from a disorder of mood, which can manifest delusions that do not reflect an independent disorder of judgment or intellect but rather a rise, in an understandable manner, from the affective disturbance. We see a clear continuity from these authors to DSM-III36 in the signs and symptoms of what we now call major depression.7,8

Discussion
In this historical sketch, which could not examine all relevant authors or provide helpful background materials, I document that, during the rise of modern psychiatry in the late 18th and early 19th century, the concept of melancholia was closely wedded to earlier views that it was fundamentally a disorder of intellect—a partial insanity—often, but not always, accompanied by sadness. This concept was seen, with modest variation, in writings from 1780 through the 1830s from both England (Cullen18,19 and Rowley22) and France (Pinel,20,21 Roubaud-Luce,23 and Esquirol24).

In this narrative, the first movement away from this paradigm was by Guislain,26 writing just after the mid-19th century, who defined elementary melancholia as a disorder of mood and then focused on the neglected but illustrative category of nondelusional melancholia. Such patients demonstrated no abnormalities of intellect or judgment. This form of melancholia was, he suggested, a disorder primarily of mood.

In 1858, 2 British authors, Bucknill and Tuke,27 went further, declaring explicitly, in the language of faculty psychology, that a disorder of the intellect was not an essential part of melancholia. However, this assertion left a key problem. How could the common occurrence of melancholia with delusions be explained if melancholia was primarily a disorder of mood?

Our final 5 authors—Griesinger,28 Sankey,30 Maudsley,31 Krafft-Ebing,32,34 and Kraepelin35—each accepted the primacy of mood in the cause of melancholia and addressed the problem of the origin of melancholic delusions. Griesinger argued that “the false ideas …are attempts at explanation.”29(p71) Sankey noted “how closely nearly all these [psychotic] symptoms are connected with the emotions.”30(p30) Maudsley stated, “The vast and formless feeling of profound misery has taken form as a concrete [delusional] idea…. The delusion is not the cause of the feeling of misery but is engendered of it.”31(p328) Krafft-Ebing presented a compelling explanation of the psychological origin of melancholic delusions including the nature of “delusional changes of relationship to the external world”34(p32) and sketched how melancholic symptoms could lead, understandably, to delusions of poverty, persecution, or punishment. Kraepelin described how “critical ability becomes overwhelmed by powerful mood fluctuations.”35(p191)

This review provides the historical context for our modern concept of mood-congruent psychotic features, which was first introduced in the research diagnostic criteria as “typical depressive delusions such as delusions of guilt, sin, poverty, nihilism, or self-deprecation,”37(p16) and then incorporated with modest changes in DSM-III36 and all subsequent DSM editions. Echoing the writings of authors reviewed herein, this list reflects delusions whose content can be understandably derived from the primary mood disturbance in major depression.

These historical observations have important implications for how we understand the nature of our psychiatric categories. A prominent narrative is that the great psychiatric nosologists of the 19th century acted as simple inductivists, seeing large numbers of patients with psychiatric disorders and, based initially on symptoms and signs and later also on course of illness, then sorting them into diagnostic categories. This inquiry suggests a more complex process.

First, as illustrated herein and described elsewhere,13,38,39 across Europe during the 19th century, systems of faculty psychology, innate functions of the human mind, were propounded by a range of philosophers, including Kant, Reid, and Stewart.10,38 These faculties provided influential a priori categories for psychiatric nosologists. As articulated explicitly by Tuke, absent a knowledge of pathophysiology, diagnostic categories should at least be based on the “affected function” (eg, “disorders of the intellect, sentiment, etc”27(p95)) rather than exclusively on symptoms.

Second, given the adoption of faculty psychology, nosologists had to confront the problem of the classification of patients apparently experiencing disorders of 2 faculties, such as individuals with delusional melancholia. Did these patients have 2 disorders or only 1 and, if so, which one? The creation of our modern concept of depression arose from an argument about the primacy of disordered intellect vs disordered mood in explaining the cause of delusional melancholia. The early model, consistent with the then dominant intellectualist view of insanity,40,41 assumed that disordered judgment was the essence of melancholia, which was first and foremost a disorder of intellect. Over the 19th century, this opinion was reversed. By the 1870s, it became widely accepted that melancholia was primarily a mood disorder. The argument that fueled that major diagnostic change appealed to understandability—that clinicians could empathically grasp how disordered mood could lead to particular kinds of delusions.

Rather than naive inductivism, a more realistic model for the development of psychiatric nosology in the 19th century would reflect a mixture of bottom-up and top-down processes. Psychiatric neuroscientists and geneticists working today are not studying the biological substrate of illnesses in patients classified from raw clinical experience. Rather, our diagnostic categories reflect clinical observations translated through mentalistic constructs from philosophers who divided the major functions of the human mind into faculties. An obvious question then is whether these faculties have a coherent biological substrate. In an 1857 essay, Henry Monro expressed concerns exactly on this point: Can we relate the metaphysical structure of mental faculties to brain structures? He wrote

Physiology points further than to the general truth that brain as a whole is the instrument of the mind as a whole, and gives us good reason to believe that the great faculties, the emotions, the sensations, and the intelligence, have distinguishable ganglia, sensoria, or spheres of action.42(p196)

The success of our efforts at understanding the biologic characteristics of major psychiatric disorders might therefore depend, in part, on how successfully the faculty psychology of 18th century philosophers reflected brain structure and function. Furthermore, our nosologic categories are influenced by empathy-based insights into the nature of psychological causation. When can a delusion be understood to derive from disordered mood rather than from a primary disorder of intellect? The degree to which these empathy-based mentalistic processes translate into a discernable neurobiology is not well known.

This history suggests that the path from patient observation to our nosologic categories and from there, hopefully, to a detectable pathophysiologic nature is more complex than is commonly realized.