Wednesday, September 25, 2019

Just 4% of participants appeared to use prior research to make probability estimates—most seemed to focus on the latest study, ignoring/discounting prior ones, even when they had more statistics classes

Is One Study as Good as Three? College Graduates Seem to Think So, Even if They Took Statistics Classes. m W Burt Thompson et al. Psychology Learning & Teaching, September 25, 2019.

Abstract: When people interpret the outcome of a research study, do they consider other relevant information such as prior research? In the current study, 251 college graduates read a single brief fictitious news article. The article summarized the findings of a study that found positive results for a new drug. Three versions of the article varied the amount and type of previous research: (a) two prior studies that found the drug did not work, (b) no prior studies of the drug, or (c) two prior studies that found the drug had a positive effect. After reading the article, participants estimated the probability the drug is effective. Average estimates were similar for the three articles, even for participants who reported more statistics experience. Overall, just 4% of participants appeared to use prior research to make probability estimates—most seemed to focus on the latest study, while ignoring or discounting prior studies. Implications for statistics education and reporting are discussed.

Keywords; Statistics education, statistics misconception, base rate neglect

Check also: Political partisans disagreed about the importance of conditional probabilities; highly numerate partisans were more polarized than less numerate partisans
It depends: Partisan evaluation of conditional probability importance. Leaf Van Boven et al. Cognition, Mar 2 2019,

And: Biased Policy Professionals. Sheheryar Banuri, Stefan Dercon, and Varun Gauri. World Bank Policy Research Working Paper 8113.

And: Dispelling the Myth: Training in Education or Neuroscience Decreases but Does Not Eliminate Beliefs in Neuromyths. Kelly Macdonald et al. Frontiers in Psychology, Aug 10 2017.

And: Wisdom and how to cultivate it: Review of emerging evidence for a constructivist model of wise thinking. Igor Grossmann. European Psychologist, in press. Pre-print:

And: Individuals with greater science literacy and education have more polarized beliefs on controversial science topics. Caitlin Drummond and Baruch Fischhoff. Proceedings of the National Academy of Sciences, vol. 114 no. 36, pp 9587–9592,

And: Expert ability can actually impair the accuracy of expert perception when judging others' performance: Adaptation and fallibility in experts' judgments of novice performers. By Larson, J. S., & Billeter, D. M. (2017). Journal of Experimental Psychology: Learning, Memory, and Cognition, 43(2), 271–288.

And: Collective Intelligence for Clinical Diagnosis—Are 2 (or 3) Heads Better Than 1? Stephan D. Fihn. JAMA Network Open. 2019;2(3):e191071,

Quashing the hopes of personalized antidepressants: "Our findings did not provide empirical support for individual differences in response to antidepressants"

Munkholm, Klaus, Stephanie Winkelbeiner, and Philipp Homan. 2019. “Individual Response to Antidepressants for Depression in Adults – a Simulation Study and Meta-analysis.” PsyArXiv. September 25. doi:10.31234/

Background. The observation that some patients appear to respond better to antidepressants for depression than others encourages the assumption that the effect of antidepressants differs between individuals and that treatment can be personalized. To test this assumption, we compared the outcome variance in the group of patients receiving antidepressants with the outcome variance of the group of patients receiving placebo in randomized controlled trials (RCTs) of adults with major depressive disorder (MDD). An increased variance in the antidepressant group would indicate individual differences in response to antidepressants. In addition, we illustrate in a simulation study why attempts to personalize antidepressant treatment using RCTs might be misguided.

Methods. We first illustrated the variance components of trials by simulating RCTs and crossover trials of antidepressants versus placebo. Second, we analyzed data of a large meta-analysis of antidepressants for depression, including a total of 222 placebo-controlled studies from the dataset that reported outcomes on the 17 or 21 item Hamilton Depression Rating Scale or the Montgomery-├ůsberg Depression Rating Scale. We performed inverse variance, random-effects meta-analyses of the variability ratio (VR) between the antidepressant and placebo groups.

Outcomes. The meta-analyses of the VR comprised 345 comparisons of 19 different antidepressants with placebo in a total of 61144 adults with an MDD diagnosis. Across all comparisons, we found no evidence for a larger variance in the antidepressant group compared with placebo overall (VR = 1.00, 95% CI: 0.98; 1.01, I2 = 0%) or for any individual antidepressant.

Interpretation. Our findings did not provide empirical support for individual differences in response to antidepressants.

Adolescent drinking has declined across many developed countries from the turn of the century; we aim to explore existing evidence examining possible reasons for this decline; the main reason could be shifts in parental practices

Why is adolescent drinking declining? A systematic review and narrative synthesis. Rakhi Vashishtha et al. Addiction Research & Theory, Sep 23 2019.

Background: Adolescent drinking has declined across many developed countries from the turn of the century. The aim of this review is to explore existing evidence examining possible reasons for this decline.

Methods: We conducted systematic searches across five databases: Medline, PsycINFO, CINAHL, Informit Health and Scopus. Studies were included if association between declining alcohol consumption and potential explanatory factors were measured over time. Narrative synthesis was undertaken due to substantial methodological heterogeneity in these studies.

Results: 17 studies met the inclusion criteria. Five studies found moderate evidence for changes in parental practices as a potential cause for the decline. Five studies that examined whether alcohol policy changes influenced the decline found weak evidence of association. Three studies explored whether alcohol use has been substituted by illicit substances but no evidence was found. Two studies examined the effect of a weaker economy; both identified increase in adolescent alcohol use during times of economic crisis. One study indicated that changes in exposure to alcohol advertising were positively associated with the decline and another examined the role of immigration of non-drinking populations but found no evidence of association. One study tested participation in organised sports and party lifestyle as a potential cause but did not use robust analytical methods and therefore did not provide strong evidence of association for the decline.

Conclusions: The most robust and consistent evidence was identified for shifts in parental practices. Further research is required using robust analytical methods such as ARIMA modelling techniques and utilising cross-national data.

Keywords: Drinking, review, decline, downward trend, adolescents

Hedonic responses to music are the result of connectivity between structures involved in auditory perception as a predictive process, & those involved in the brain's dopaminergic reward system

Musical anhedonia and rewards of music listening: current advances and a proposed model. Amy M. Belfi, Psyche Loui. Annals of the New York Academy of Sciences, September 23 2019.

Abstract: Music frequently elicits intense emotional responses, a phenomenon that has been scrutinized from multiple disciplines that span the sciences and arts. While most people enjoy music and find it rewarding, there is substantial individual variability in the experience and degree of music‐induced reward. Here, we review current work on the neural substrates of hedonic responses to music. In particular, we focus the present review on specific musical anhedonia, a selective lack of pleasure from music. Based on evidence from neuroimaging, neuropsychology, and brain stimulation studies, we derive a neuroanatomical model of the experience of pleasure during music listening. Our model posits that hedonic responses to music are the result of connectivity between structures involved in auditory perception as a predictive process, and those involved in the brain's dopaminergic reward system. We conclude with open questions and implications of this model for future research on why humans appreciate music.


The capacity to perceive, produce, and appreciate music, together termed musicality,1 has been a growing topic of interest in the past 20 years of cognitive neuroscience. While most cognitive neuroscience studies on musicality focus on music perception and production skills, there has been a recent explosion of interest in the appreciation of music.2, 3 Multiple research programs in the cognitive neuroscience of music have involved comparing participants with different types and levels of musical training.4-7 However, to cognitive neuroscientists who are not particularly concerned with music, these studies may appear to be highly specialized and of limited interest as they seem to focus on a special population—highly trained musicians. In contrast, studies on the appreciation of music can be thought of as more general and inclusive, encompassing the vast majority of humans regardless of formal musical training.

Humans show knowledge of fundamental musical building blocks, such as rhythm and beat, from as early as 1 day old,8 and as shown from the success of the multibillion‐dollar music industry, humans around the world enjoy music. One of the most frequently reported reasons for listening to music is the overwhelming influence it has on feelings and emotions.9 Music has been deemed an ultimate group bonding activity;10, 11 this is supported by structural features of melody, harmony, and scales that are observed across many cultures,12 as well as the ubiquity of songs that serve social functions, such as lullabies, dance songs, healing songs, and love songs, across cultures.13 Singing and making music together enhance social interactions and group bonding14, 15 and elicit physiological effects that are observable from infancy.16 Even in the few cultures where music is not produced in groups, members of these cultures nevertheless enjoy singing for each other,17 suggesting that the capacity for music enjoyment, that is, the rewarding aspects of music, may be intrinsic to humans as a social species. Together, these lines of research suggest that understanding why humans love music may offer a window into how humans interact in a social environment.

The rapid growth of research on musical enjoyment, specifically in cognitive neuroscience, may also be facilitated in part by recent findings on the role of dopamine in coding for prediction and reward. Since the classic observations that stimulating dopaminergic neurons elicits motivated behavior,18 and that dopaminergic neurons signal changes in the predictability of rewards,19 thousands of studies have identified a set of regions within the human brain that are especially sensitive to reward. These regions center around the midbrain (the ventral tegmental area and substantia nigra (SN)), the dorsal and ventral striatum (VS) (the caudate, putamen, nucleus accumbens (NAcc), and globus pallidus), and the medial prefrontal cortex (mPFC).20 These areas, which we refer to throughout this article as the reward system, are reliably activated during the experience of unconditionally rewarding, evolutionarily salient stimuli, such as food and sex, as well as stimuli that are strongly associated with such rewards, such as money. Findings from the monetary incentive delay task show that cues that predict monetary rewards reliably activate the striatum and mPFC,21 core areas of the reward network. Interestingly, activity in the striatum is also observed when social stimuli (faces) are substituted for monetary rewards,22, 23 suggesting that social and monetary cues tap into “common neural currency” of the reward system.22

The findings that food and sex activate the same reward system can be readily explained as being evolutionarily adaptive: being motivated to seek out these stimuli improves our chances of survival. In contrast, the adaptive value of music—and aesthetic stimuli more generally—is less obvious. Nevertheless, much recent work has shown that music engages the reward system (as reviewed below; see also Ref. 24). While music ranks highly among the pleasures in life,25, 26 recent work has identified a unique condition of people with specific musical anhedonia:27, 28 people who are insensitive to the rewarding aspects of music despite normal hedonic responses to other sensory and aesthetic stimuli, and normal auditory perceptual abilities.29 The existence of this unique population raises many important questions. Some of these questions include:

.    The nature versus nurture of musical reward sensitivity: Does musical anhedonia run in families? When and how did it develop? What, if any, genetic underpinnings might predispose an individual toward musical anhedonia? What is its developmental trajectory?

.    Domain‐specificity versus domain‐generality of reward sensitivity: Are there specific neural pathways for music reward that are separate from general reward? What are the neural pathways through which specific stimuli (such as music) come to have privileged access to the reward system? What endows a certain stimulus with privileged access to the reward system?

.    Psychological associations and clinical comorbidity: What are the associations between musical anhedonia and psychological traits, both in the normal range (e.g., big five personality traits) and clinical populations? What is the comorbidity between musical anhedonia and personality, mood, and communication disorders?

.    The evolution of music: To what extent do nonhuman animals also show reward sensitivity to music? Have there been people with musical anhedonia for as long as there has been music? By extension, if people with musical anhedonia have survived for generations with no apparent disadvantage alongside the rest of the population who have normal reward sensitivity to music, then the lack of reward sensitivity to music seems not to affect their survival. If this is the case, then why do we seek out music?

Here, we review the recent cognitive neuroscience evidence for musical engagement of the reward system, as well as an extreme end of the spectrum of individual differences in sensitivity to music reward in specific musical anhedonia. Based on our review of the literature, we propose a model that accounts for the nature of the auditory access to the human reward system, and its disruption in musical anhedonia.

The effect of close elections on the life expectancy of politicians: Winners outlive losers by over a year, on average

Run for your life? The effect of close elections on the life expectancy of politicians. Mark Borgschulte, Jacob Vogler. Journal of Economic Behavior & Organization, September 24 2019.

•    Examine effect of winning or losing a close election on the life expectancy of candidates.
•    Regression discontinuity design estimated using newly-collected data on winning and losing candidates for governor, senator, and representative in the United States.
•    Winners outlive losers by over a year, on average.
•    Largest effects for governors and candidates who run later in US history.
•    No discernable effect of stress on life expectancy.

Abstract: We estimate the causal effect of election to political office on natural lifespan using a regression discontinuity design and a novel dataset of winning and losing candidates for US governor, senator, and House representative. We find that candidates gain over a year of life from winning a close election. The effect is strongest for governors, and has grown larger over the course of US history. We also examine the effect of stress experienced in office, finding that serving in more challenging situations is not associated with reduced lifespan.