Friday, January 18, 2019

Massive redundancy: The great majority of nerve cells in the intact brain are permanently silent, in inhibited state at high energetic costs, until stress and disease attack, developing psychiatric symptoms

The dark matter of the brain. Saak V. Ovsepian. Brain Structure and Function,

Abstract: The bulk of brain energy expenditure is allocated for maintenance of perpetual intrinsic activity of neurons and neural circuits. Long-term electrophysiological and neuroimaging studies in anesthetized and behaving animals show, however, that the great majority of nerve cells in the intact brain do not fire action potentials, i.e., are permanently silent. Herein, I review emerging data suggesting massive redundancy of nerve cells in mammalian nervous system, maintained in inhibited state at high energetic costs. Acquired in the course of evolution, these collections of dormant neurons and circuits evade routine functional undertakings, and hence, keep out of the reach of natural selection. Under penetrating stress and disease, however, they occasionally switch in active state and drive a variety of neuro-psychiatric symptoms and behavioral abnormalities. The increasing evidence for widespread occurrence of silent neurons warrants careful revision of functional models of the brain and entails unforeseen reserves for rehabilitation and plasticity.

Keywords: Silent neurons Brain evolution fMRI Synchronous activity Schizophrenia; disinhibition; neuronal plasticity

Similar to cosmology and genomic research, advances in functional brain imaging have been also highly contin-gent on the arrival of cutting-edge technologies and research tools. The glorious custom of functional brain studies set by Hans Berger, Charles Sherrington, Graham Brown, and others prompted major breakthroughs, which climaxed in arrival of innovative methods enabling non-invasive visuali-zation of intrinsic and task-driven changes in brain activity and metabolism (Roy and Sherrington 1890; Berger 1940; Logothetis 2008). The gold standard here has been relat-ing selected brain structures to specific neural functions, to gain critical information for elucidating normal and diseased brain activity and assisting in diagnostics of neu-rological and psychiatric disease. Like in cosmology and genomic studies, the explosive advances in neuroscience research and imaging have unveiled major and surprising unknowns at the core of functional models of the brain. In particular, analysis of energy consumption changes related to brain activity showed that baseline expenditure of calo-ries at rest is remarkably stable, with extra energy required for processing environmental inputs comprising only a very small percentage (~ 1%) of the total energy usage. While the general notion is that bulk of the brain energy is allocated for maintenance of intrinsic activity, the nature and func-tionality of processes absorbing massive amount of calories remain to be determined. According to Raichle, the meta-bolic state of the brain circuits could be the cause, rather than the consequence of neural activity, with best part of neural energy expenditure remaining unaccounted (Raichle 2010, 2015). Recent estimates, which are largely based on positron emission tomography (PET) and functional mag-netic resonance imaging (fMRI) are especially revealing, and propose that with a fierce appetite for glucose and oxygen, the human brain, which constitutes only ~ 2% of the body weight, consumes over ~ 20% of the total body energy. The mechanistic analysis of this intriguing phenomenon is cur-rently hindered by limited sensitivity and resolution of imag-ing methods, which despite major improvements, remain indirect and crude sensors of neuronal mass action, unable to distinguish even basic neurobiological processes such as excitation and inhibition (Logothetis 2008; Poplawsky et al. 2017). Remarkably, hemodynamic measurements combined with autoradiography studies showed that similar to excita-tion, inhibition can be associated with increased perfusion of neural tissue and rise in metabolic activity, although these effects can vary depending on the experimental paradigm, partly owning to effects GABA on micro-vessel dynamics (Jueptner and Weiller 1995).Despite the results of cost-based analysis suggesting greater significance of intrinsic as opposed to evoked brain activity, single-unit electrophysiological recordings and cellular resolution imaging in animal models show that the overwhelming majority of neurons (60–90%) in anesthetized and awake animals are permanently silent (i.e., do not fire action potentials) or show very sparse firing (Berger 1940; Shoham et al. 2006) (Table 1). These findings not only prompt questions concerning the share of inactive neurons in brain energy expenditure, but also their neurochemical identity, phylogenetic origin, and place in functional brain models. In the following, I consider emerging data suggest-ing that vast numbers of inactive neurons are not a result of experimental intervention but reflect the generic state of brain affairs. I discuss numerous evidence, implying that these neurons could emerge as a result of the trade-off for high conservation of neural evolution, through selection of loss of function, which favored retention of dormant neu-rons in permanently inhibited state. I review remarkable examples of reactivation of silent neurons and circuits by disinhibition, with their entry into the realm of psyche and behavior, producing an array of maladaptive fits or relict activity. Finally, I propose that neural circuits neutralized by persistent inhibition can afford vast reserves for plasticity and neo-functionalization, with invigorating or disruptive consequence.

It is often claimed that 97 per cent of scientists conclude that humans are causing global warming. Is that really true? No. It is a zombie statistic.

Ian Plimer: 97% Of Scientists Agree On Nothing. The Australian, January 17 2019.

It is often claimed that 97 per cent of scientists conclude that humans are causing global warming. Is that really true? No. It is a zombie statistic.

In the scientific circles I mix in, there is an overwhelming scepticism about human-induced climate change. Many of my colleagues claim that the mantra of human-induced global warming is the biggest scientific fraud of all time and future generations will pay dearly.

If 97 per cent of scientists agree that there is human-induced climate change, you’d think they would be busting a gut to vanquish climate sceptics in public debates. Instead, many scientists and activists are expressing confected outrage at the possibility of public debates because the science is settled. After all, 97 per cent of scientists agree that human emissions drive global warming and there is no need for further discussion.

In my 50-year scientific career, I have never seen a hypothesis where 97 per cent of scientists agree. At any scientific conference there are collections of argumentative sods who don’t agree about anything, argue about data, how data was collected and the conclusions derived from data.

Scepticism underpins all science, science is underpinned by repeatable validated evidence and scientific conclusions are not based on a show of hands, consensus, politics or feelings. Scientists, just like lawyers, bankers, unionists, politicians and those in all other fields, can make no claim to being honest or honourable, and various warring cliques of scientists have their leaders, followers, outsiders and enemies. Scientists differ from many in the community because they are allegedly trained to be independent. Unless, of course, whacking big research grants for climate “science” are waved in front of them.

The 97 per cent figure derives from a survey sent to 10,257 people with a self-interest in human-induced global warming who published “science” supported by taxpayer-funded research grants. Replies from 3146 respondents were whittled down to 77 self-appointed climate “scientists” of whom 75 were judged to agree that human-induced warming was taking place. The 97 per cent figure derives from a tribe with only 75 members. What were the criteria for rejecting 3069 respondents? There was no mention that 75 out of 3146 is 2.38 per cent. We did not hear that 2.38 per cent of climate scientists with a self-interest agreed that humans have played a significant role in changing climate and that they are recipients of some of the billions spent annually on climate research.

Another recent paper on the scientific consensus of human-induced climate change was a howler. Such papers can be published only in the sociology or environmental literature.

The paper claimed that published scientific papers showed there was a 97.1 per cent consensus that man had caused at least half of the 0.7C global warming since 1950. How was this 97.1 per cent figure determined? By “inspection” of 11,944 published papers. Inspection is not rigorous scholarship. There was no critical reading and understanding derived from reading 11,944 papers. This was not possible as the study started in March 2012 and was published in mid-2013, hence only a cursory inspection was possible.

What was inspected? By whom?

The methodology section of the publication gives the game away. “This letter was conceived as a ‘citizen science’ project by volunteers contributing to the Skeptical Science website ( In March 2012, we searched the Institute for Scientific Information Web of Science for papers published from 1991-2011 using topic searches for ‘global warming’ or ‘global climate change’.”

This translates as: This study was a biased compilation of opinions from non-scientific, politically motivated volunteer activists who used a search engine for key words in 11,944 scientific papers, were unable to understand the scientific context of the use of “global warming” and “global climate change”, who rebadged themselves as “citizen scientists” to hide their activism and ignorance, who did not read the complete papers and were unable to evaluate critically the diversity of science published therein.

The conclusions were predictable because the methodology was not dispassionate and involved decisions by those who were not independent.

As part of a scathing critical analysis of this paper by real scientists, the original 11,944 papers were read and the readers came to a diametrically opposite conclusion. Of the 11,944 papers, only 41 explicitly stated that humans caused most of the warming since 1950 (0.3 per cent). Of the 11,944 climate “science” papers, 99.7 per cent did not say that carbon dioxide caused most of the global warming since 1950. It was less than 1 per cent and not one paper endorsed a man-made global warming catastrophe.

Political policy and environmental activism rely on this fraudulent 97 per cent consensus paid for by the taxpayer to rob the taxpayer further with subsidies for bird-and-bat-chomping wind turbines, polluting solar panels and handouts to those with sticky fingers in the international climate industry. It’s this alleged 97 per cent consensus that has changed our electricity from cheap and reliable to expensive and unreliable.

Activists with no skin in the game are setting the scene for economic suicide. Time for yellow shirts to shirt-front politicians about their uncritical acceptance of a fraud that has already cost the community hundreds of billions of dollars.

Emeritus professor Ian Plimer’s latest book, The Climate Change Delusion and the Great Electricity Ripoff, is published by Connor Court. He is a member of the GWPF’s Academic Advisory Council

Check also Consensus? What Consensus? Andrew Montford, GWPF, Sep 2013,

Early adoption of recusant identities & oppositional agencies leading to a polarized choice: Either seek self-verification elsewhere by avoiding institutions such as schools, labor markets, & marriage or intensely engage them

Jaynes, Gerald D., A Behavioral Interpretation of the Origins of African American Family Structure (November 30, 2018). Cowles Foundation Discussion Paper No. 2156.

Abstract: 1960 to 1980 doubling (21% to 41%) of black children in one-parent families emerged from 1940-to-1970 urbanization converging population toward urbanized blacks’ historically stable high rate, not post-1960 welfare liberalization or deindustrialization. Urban and rural child socializations structured different Jim Crow Era black family formations. Agrarian economic enclaves socialized conformity to Jim Crow and two-parent families; urban enclaves rebellion, male joblessness, and destabilized families. Proxying urban/rural residence at age 16 for socialization location, logistic regressions on sixties census data confirm the hypothesis. Racialized urban socialization negatively affected two-parent family formation and poverty status of blacks but not whites.

Keywords: Behavioral Economics, Logistic Regression

The hypothesis underlying my reinterpretation of the origins of contemporary black family structure is, through the late 20th Century, throughout American history, structural differences in the race relations and economic discrimination confronting blacks in rural versus urban locations produced distinct childhood socialization experiences. These distinct socialization experiences exposed urbanized black children (north and south) to large numbers of recusant adults -- men and women socially alienated by urban job ceilings and truculently refusing to acquiesce to race relations based in white supremacy. Observation of and interaction with recusant adults and discriminatory economic institutions put urbanized black children at great risk of early projection of a failure to achieve self-verification of an acceptable social identity. The developmental outcome was early adoption of recusant identities and oppositional agencies leading to a polarized choice: either seek self-verification elsewhere by avoiding institutions such as schools, labor markets, and marriage (causing high rates of single parent families), or (attempting to alter one’s receptionn such institutions) intensely engage them leading to civil rights activism and a rising black middle class. In contrast, rural black children were more likely exposed to adults seeking self-verification by striving to climb the agricultural tenure ladder a life goal requiring conforming to behavioral norms based in the era’s white supremacist race relations. Failure to self-verify a positive self-image by achieving land ownership or rental tenancy occurred later in life when the adoption of oppositional agencies was greatly mitigated.

Cerebellar modulation of the reward circuitry and social behavior: Deep cerebellar nuclei implicated in addictive behavior and autism spectrum disorder, cognitive affective syndrome, and schizophrenia

Cerebellar modulation of the reward circuitry and social behavior. Ilaria Carta et al. Science Jan 18 2019:Vol. 363, Issue 6424, eaav0581. DOI: 10.1126/science.aav0581

The cerebellum and reward-driven behavior
Damage to the cerebellum manifests itself in various forms of cognitive impairment and abnormal social behavior. However, the exact role the cerebellum plays in these conditions is far from clear. Working in mice, Carta et al. found direct projections from the deep cerebellar nuclei to the brain's reward center, a region called the ventral tegmental area (see the Perspective by D'Angelo). These direct projections allowed the cerebellum to play a role in showing a social preference. Intriguingly, this pathway was not prosocial on its own. Cerebellar inputs into the ventral tegmental area were more active during social exploration. Depolarization of ventral tegmental area neurons thus represents a similar reward stimulus as social interaction for mice.

INTRODUCTION: Although the cerebellum has long been considered to be a purely motor structure, recent studies have revealed that it also has critical nonmotor functions. Cerebellar dysfunction is implicated in addictive behavior and in mental disorders such as autism spectrum disorder (ASD), cognitive affective syndrome, and schizophrenia. The cerebellum is well poised to contribute to behavior because it receives a wide array of cortical and sensory information and is subject to control by a number of neuromodulators. To perform its function, the cerebellum is believed to integrate these diverse inputs to provide the rest of the brain with predictions required for optimal behavior. Although there are many pathways for this to occur in the motor domain, fewer exist for the nonmotor domain.

RATIONALE: There are no direct pathways emanating from the cerebellum that have been shown to serve nonmotor functions. We hypothesized that the cerebellum may contribute to motivated behavior by a direct projection to the ventral tegmental area (VTA), a structure that is critical for the perception of reward and control of social behaviors. Such a projection would explain why functional imaging experiments indicate that the cerebellum plays a role in addiction and would provide one potential mechanism by which cerebellar dysfunction might contribute to the symptoms of mental disorders.

RESULTS: In mice, we found that monosynaptic excitatory projections from the cerebellar nuclei to the VTA powerfully activate the reward circuitry and contribute to social behavior. Using anatomical tracing, we showed that axonal projections from the cerebellar nuclei form synapses with both dopaminergic and nondopaminergic neurons in the VTA. The cerebello-VTA (Cb-VTA) projections were powerful and their optogenetic stimulation robustly increased the activity of VTA neurons both in vivo and in vitro. Behavioral tests to examine reward processing showed that stimulation of the Cb-VTA projections was sufficient to cause short-term and long-term place preference, thereby demonstrating that the pathway was rewarding. Although optogenetic inhibition of Cb-VTA projections was not aversive, it completely abolished social preference in the three-chamber test for sociability, which suggests that the cerebellar input to the VTA is required for normal social behavior. A role for the cerebellum in social behavior was also indicated by correlation between calcium activity in these axons and performance in the three-chamber test. However, optogenetic activation of the Cb-VTA inputs was not prosocial, hence the pathway was not sufficient for social behavior.

CONCLUSION: The Cb-VTA pathway described here is a monosynaptic projection from the cerebellum to a structure known primarily for its nonmotor functions. Our data support a role for the cerebellum in reward processing and in control of social behavior. We propose that this Cb-VTA pathway may explain, at least in part, the association between the cerebellum and addictive behaviors, and provides a basis for a role for the cerebellum in other motivated and social behaviors. In addition to contributing to reward processing, the VTA also targets a number of other brain regions, such as the prefrontal cortex, that in turn sustain a large repertoire of motor and nonmotor behaviors. Direct cerebellar innervation of the VTA provides a pathway by which the cerebellum may modulate these diverse behaviors. The Cb-VTA pathway delineated here provides a mechanism by which cerebellar dysfunction, by adversely affecting the VTA and its targets, might contribute to mental disorders such as ASD and schizophrenia.


Elders were less likely to recollect their original judgment than young adults, & had to reconstruct it more frequently; & outcome knowledge distorted more the reconstruction of original judgment in elders

Groß, J., & Pachur, T. (2019). Age differences in hindsight bias: A meta-analysis. Psychology and Aging,

Abstract: After people have learned a fact or the outcome of an event, they often overestimate their ability to have known the correct answer beforehand. This hindsight bias has two sources: an impairment in direct recall of the original (i.e., uninformed) judgment after presentation of the correct answer (recollection bias) and a reconstruction of the original judgment that is biased toward the correct answer (reconstruction bias). Research on how cognitive aging affects these two sources of hindsight bias has produced mixed results. To synthesize the available findings, we conducted a meta-analysis of nine studies (N = 366 young, N = 368 older adults). We isolated the probabilities of recollection, recollection bias, and reconstruction bias with a Bayesian, three-level hierarchical implementation of the multinomial processing tree model of hindsight bias (Erdfelder & Buchner, 1998). Additionally, we quantified the magnitude of bias in the reconstructed judgment. Overall, older adults were less likely to recollect their original judgment than young adults, and thus had to reconstruct it more frequently. Importantly, whereas outcome knowledge impaired recollection of the original judgment (i.e., recollection bias) to a similar extent in both age groups, outcome knowledge was more likely to distort reconstruction of the original judgment (i.e., reconstruction bias) in older adults. In addition, the magnitude of bias in the reconstructed judgments was slightly larger in older than in young adults. Our results provide the basis for a targeted investigation of the mechanisms driving these age differences.

Aggression in mice is differentially predicted by the volumes of anterior and midcingulate cortex

Aggression in BALB/cJ mice is differentially predicted by the volumes of anterior and midcingulate cortex. Sabrina van Heukelum et al. Brain Structure and Function,

Abstract: Anterior cingulate cortex (ACC) and midcingulate cortex (MCC) have been implicated in the regulation of aggressive behaviour. For instance, patients with conduct disorder (CD) show increased levels of aggression accompanied by changes in ACC and MCC volume. However, accounts of ACC/MCC changes in CD patients have been conflicting, likely due to the heterogeneity of the studied populations. Here, we address these discrepancies by studying volumetric changes of ACC/MCC in the BALB/cJ mouse, a model of aggression, compared to an age- and gender-matched control group of BALB/cByJ mice. We quantified aggression in BALB/cJ and BALB/cByJ mice using the resident–intruder test, and related this to volumetric measures of ACC/MCC based on Nissl-stained coronal brain slices of the same animals. We demonstrate that BALB/cJ behave consistently more aggressively (shorter attack latencies, more frequent attacks, anti-social biting) than the control group, while at the same time showing an increased volume of ACC and a decreased volume of MCC. Differences in ACC and MCC volume jointly predicted a high amount of variance in aggressive behaviour, while regression with only one predictor had a poor fit. This suggests that, beyond their individual contributions, the relationship between ACC and MCC plays an important role in regulating aggressive behaviour. Finally, we show the importance of switching from the classical rodent anatomical definition of ACC as cingulate area 2 and 1 to a definition that includes the MCC and is directly homologous to higher mammalian species: clear behaviour-related differences in ACC/MCC anatomy were only observed using the homologous definition.

Keywords: Prefrontal cortex Rodent Brain volume Aggression Mouse model

Is Language Required to Represent Others’ Mental States? Language does not form an essential part of the process of reasoning online (“in the moment”) about false beliefs

Is Language Required to Represent Others’ Mental States? Evidence From Beliefs and Other Representations. Steven Samuel et al. Cognitive Science,

Abstract: An important part of our Theory of Mind—the ability to reason about other people's unobservable mental states—is the ability to attribute false beliefs to others. We investigated whether processing these false beliefs, as well as similar but nonmental representations, is reliant on language. Participants watched videos in which a protagonist hides a gift and either takes a photo of it or writes a text about its location before a second person inadvertently moves the present to a different location, thereby rendering the belief and either the photo or text false. At the same time, participants performed either a concurrent verbal interference task (rehearsing strings of digits) or a visual interference task (remembering a visual pattern). Results showed that performance on false belief trials did not decline under verbal interference relative to visual interference. We interpret these findings as further support for the view that language does not form an essential part of the process of reasoning online (“in the moment”) about false beliefs.

Both numerical magnitude & order processing were uniquely related to arithmetic achievement, beyond domain‐general factors (intellectual ability, working memory, inhibitory control, & non‐numerical ordering)

Disentangling the Mechanisms of Symbolic Number Processing in Adults’ Mathematics and Arithmetic Achievement. Josetxu Orrantia et al. Cognitive Science,

Abstract: A growing body of research has shown that symbolic number processing relates to individual differences in mathematics. However, it remains unclear which mechanisms of symbolic number processing are crucial—accessing underlying magnitude representation of symbols (i.e., symbol‐magnitude associations), processing relative order of symbols (i.e., symbol‐symbol associations), or processing of symbols per se. To address this question, in this study adult participants performed a dots‐number word matching task—thought to be a measure of symbol‐magnitude associations (numerical magnitude processing)—a numeral‐ordering task that focuses on symbol‐symbol associations (numerical order processing), and a digit‐number word matching task targeting symbolic processing per se. Results showed that both numerical magnitude and order processing were uniquely related to arithmetic achievement, beyond the effects of domain‐general factors (intellectual ability, working memory, inhibitory control, and non‐numerical ordering). Importantly, results were different when a general measure of mathematics achievement was considered. Those mechanisms of symbolic number processing did not contribute to math achievement. Furthermore, a path analysis revealed that numerical magnitude and order processing might draw on a common mechanism. Each process explained a portion of the relation of the other with arithmetic (but not with a general measure of math achievement). These findings are consistent with the notion that adults’ arithmetic skills build upon symbol‐magnitude associations, and they highlight the effects that different math measures have in the study of numerical cognition.

When the Muses Strike: Creative Ideas of Physicists and Writers Routinely Occur During Mind Wandering

When the Muses Strike: Creative Ideas of Physicists and Writers Routinely Occur During Mind Wandering. Shelly L. Gable, Elizabeth A. Hopper, Jonathan W. Schooler. Psychological Science,

Abstract: How often are creative ideas generated during episodes of mind wandering, and do they differ from those generated while on task? In two studies (N = 98, N = 87), professional writers and physicists reported on their most creative idea of the day, what they were thinking about and doing when it occurred, whether the idea felt like an “aha” moment, and the quality of the idea. Participants reported that one fifth of their most significant ideas of the day were formed during spontaneous task-independent mind wandering—operationalized here as (a) engaging in an activity other than working and (b) thinking about something unrelated to the generated idea. There were no differences between ratings of the creativity or importance of ideas that occurred during mind wandering and those that occurred on task. However, ideas that occurred during mind wandering were more likely to be associated with overcoming an impasse on a problem and to be experienced as “aha” moments, compared with ideas generated while on task.

Keywords: creativity, mind wandering, insight, open data, open materials

Disgust, sushi consumption, benefits, religion, and other predictors of acceptance of insects as food by Americans and Indians

Disgust, sushi consumption, and other predictors of acceptance of insects as food by Americans and Indians. Matthew B. Ruby, Paul Rozin. Food Quality and Preference,

•    Americans (82%) were more willing to try eating insects than were Indians (48%).
•    Benefits: Agreement was highest that rearing insects has low space requirements.
•    Risks: Agreement was highest that eating insects may cause allergic reactions.
•    USA: Willingness to eat insects was best predicted by Disgust and Benefit beliefs.
•    Consumption of sushi is a good predictor of insect acceptance.


Insects are an important human food source, especially in developing countries, because of their efficiency at converting plant foods into animal protein, and their relatively low environment impact. The present study builds on some prior research on eating insects by surveying Indian and American adults. A composite measure of insect acceptance is developed. The results confirm prior findings that Americans are more accepting of insects as a potential food than Indians, and that men are more accepting than women. Substantially more Indians than Americans consider insect ingestion a violation of a protected/sacred value, suggesting a moral objection. Attitudes to and beliefs about insects and insect consumption are decomposed through factor analysis into the same five factors in both countries: Benefits, Risks, Disgust, Religion, and Suffering. Multiple regression indicates that for Americans, Disgust is the major predictor, followed by Benefits. For Indians, the best predictor is Benefits, followed by Disgust and Religion. In both countries, frequency of sushi consumption (a food commonly met with disgust when it was first introduced) is also a significant and substantial predictor of insect acceptance.

Investigating gender differences in school burnout from a self-worth perspective: Girls take school too seriously

Do girls take school too seriously? Investigating gender differences in school burnout from a self-worth perspective. Julia Herrmann, Karoline Koeppen, Ursula Kessels. Learning and Individual Differences, Volume 69, January 2019, Pages 150-161.

•    Lower school achievement is associated with higher levels of school burnout.
•    Independent of grades, girls report higher levels of exhaustion.
•    Girls report higher academic contingent self-esteem and lower global self-esteem.
•    Academic contingent SE and motivation explain gender differences in exhaustion.

Abstract: Recent investigations have suggested that a considerable percentage of teenagers, especially those in academic track schools, report school-related burnout symptoms (exhaustion, cynicism and inadequacy). Low school achievement and female gender are discussed as risk factors for the syndrome. We investigated school burnout from an individual differences perspective, focusing on aspects of self-esteem (global self-esteem; academic contingent self-esteem) and their associations with specific types of motivational regulation (intrinsic; extrinsic) in a sample of N = 649 9th graders (59% female; 40% males) from six academic track schools in Germany. We hypothesized that gender would be associated with school burnout symptoms and that global self-esteem, academic contingent self-esteem, intrinsic motivation, and extrinsic motivation would mediate the relations. We tested these associations in a structural equation model that was adjusted for grades. Girls' higher scores on exhaustion could be explained through pathways via self-esteem aspects and motivation. Results may inform prevention practices.