Whole-brain gray matter maturation trajectories associated with autistic traits from adolescence to early adulthood.

A growing number of evidence supports a continued distribution of autistic traits in the general population. However, brain maturation trajectories of autistic traits as well as the influence of sex on these trajectories remain largely unknown. We investigated the association of autistic traits in the general population, with longitudinal gray matter (GM) maturation trajectories during the critical period of adolescence. We assessed 709 community-based adolescents (54.7% women) at age 14 and 22. After testing the effect of sex, we used whole-brain voxel-based morphometry to measure longitudinal GM volumes changes associated with autistic traits measured by the Social Responsiveness Scale (SRS) total and sub-scores. In women, we observed that the SRS was associated with slower GM volume decrease globally and in the left parahippocampus and middle temporal gyrus. The social communication sub-score correlated with slower GM volume decrease in the left parahippocampal, superior temporal gyrus, and pallidum; and the social cognition sub-score correlated with slower GM volume decrease in the left middle temporal gyrus, the right ventromedial prefrontal and orbitofrontal cortex. No longitudinal association was found in men. Autistic traits in young women were found to be associated with specific brain trajectories in regions of the social brain and the reward circuit known to be involved in Autism Spectrum Disorder. These findings support both the hypothesis of an earlier GM maturation associated with autistic traits in adolescence and of protective mechanisms in women. They advocate for further studies on brain trajectories associated with autistic traits in women.

Longitudinal associations between adolescent catch-up sleep, white-matter maturation and internalizing problems.

Sleep is an important contributor for neural maturation and emotion regulation during adolescence, with long-term effects on a range of white matter tracts implicated in affective processing in at-risk populations. We investigated the effects of adolescent sleep patterns on longitudinal changes in white matter development and whether this is related to the emergence of emotional (internalizing) problems. Sleep patterns and internalizing problems were assessed using self-report questionnaires in adolescents recruited in the general population followed up from age 14-19 years (N = 111 White matter structure was measured using diffusion tensor imaging (DTI) and estimated using fractional anisotropy (FA). We found that longitudinal increases in time in bed (TIB) on weekends and increases in TIB-variability between weekdays to weekend, were associated with an increase in FA in various interhemispheric and cortico-striatal tracts. Extracted FA values from left superior longitudinal fasciculus mediated the relationship between increases in TIB on weekends and a decrease in internalizing problems. These results imply that while insufficient sleep might have potentially harmful effects on long-term white matter development and internalizing problems, longer sleep duration on weekends (catch-up sleep) might be a natural counteractive and protective strategy.

Chronotype, Longitudinal Volumetric Brain Variations Throughout Adolescence, and Depressive Symptom Development.

OBJECTIVE: Adolescence is a critical period for circadian rhythm, with a strong shift toward eveningness around age 14. Also, eveningness in adolescence has been found to predict later onset of depressive symptoms. However, no previous study has investigated structural variations associated with chronotype in early adolescence and how this adds to the development of depressive symptoms. METHOD: Assessment of 128 community-based adolescents (51% girls) at age 14 and 19 years was performed. Using whole-brain voxel-based morphometry, baseline (at age 14) regional gray matter volumes (GMVs), follow-up (at age 19) regional GMVs, and longitudinal changes (between 14 and 19) associated with Morningness/Eveningness Scale in Children score and sleep habits at baseline were measured. The association of GMV with depressive symptoms at 19 years was studied, and the role of potential clinical and genetic factors as mediators and moderators was assessed. RESULTS: Higher eveningness was associated with larger GMV in the right medial prefrontal cortex at ages 14 and 19 in the whole sample. GMV in this region related to depressive symptoms at age 19 in catechol-O-methyltransferase (COMT) Val/Val, but not in Met COMT, carriers. Larger GMV also was observed in the right fusiform gyrus at age 14, which was explained by later wake-up time during weekends. CONCLUSION: In adolescence, eveningness and its related sleep habits correlated with distinct developmental patterns. Eveningness was specifically associated with GMV changes in the medial prefrontal cortex; this could serve as a brain vulnerability factor for later self-reported depressive symptoms in COMT Val/Val carriers.

Early liaison psychiatry consultations and general hospital readmission: A retrospective cohort study.

BACKGROUND: Readmission rates are under growing scrutiny as an indicator of quality of care as much as a potential source of savings. Patients with comorbid psychiatric conditions are more likely to be readmitted, so Consultation-Liaison Psychiatry (CLP) may play a role in lowering readmission rates. METHOD: In this retrospective cohort study conducted in a general hospital in Paris, France, all consecutive adult inpatients referred for the first time to CLP from January 2008 to December 2016, were included. The main outcomes were 30-day and 7-day readmissions in the same hospital, excluding iterative and planned stays. The objective of this study is to determine whether the timing of psychiatric consultations is associated with 30-day and 7-day readmission rates. RESULTS: A total of 4498 inpatients (2298(51·1%) women, age = 59·8(±19·3) years) were referred to CLP. Adjusting for age, sex, place of residence, year of admission, type of ward, psychiatric diagnosis and disease severity, later consultation was associated with higher 30-day and 7-day readmission rates (adjusted Odds Ratio [95% confidence interval]:1.21[1·10-1·33] and 1·26[1·11-3·13], respectively). Further adjusting for length of stay, the association remained significant for 7-day readmission (1.28[1·05-1·57]). After stratification on the length of stay, for stays in the highest tercile (i.e., >21 days) an intervention after day 3 (versus before) was associated with 30-day and 7-day readmission rates of 15·8% versus 8·6%(1·81 [1·11-3·13]) and 4·9% versus 1·8%(2·98[1·16-9·88]), respectively. CONCLUSION: Earlier psychiatric consultation was associated with fewer 30-day and 7-day readmissions. Interventional studies are needed to show that proactive CLP teams could help general hospitals to improve quality of care and make significant economic savings.

Neuroimaging evidence for structural correlates in adolescents resilient to polysubstance use: A five-year follow-up study.

Early initiation of polysubstance use (PSU) is a strong predictor of subsequent addiction, however scarce individuals present resilience capacity. This neuroimaging study aimed to investigate structural correlates associated with cessation or reduction of PSU and determine the extent to which brain structural features accounted for this resilient outcome. Participants from a European community-based cohort self-reported their alcohol, tobacco and cannabis use frequency at ages 14, 16 and 19 and had neuroimaging sessions at ages 14 and 19. We included three groups in the study: the resilient-to-PSU participants showed PSU at 16 and/or 14 but no more at 19 (n = 18), the enduring polysubstance users at 19 displayed PSU continuation from 14 or 16 (n = 193) and the controls were abstinent or low drinking participants (n = 460). We conducted between-group comparisons of grey matter volumes on whole brain using voxel-based morphometry and regional fractional anisotropy using tract-based spatial statistics. Random-forests machine-learning approach generated individual-level PSU-behavior predictions based on personality and neuroimaging features. Adolescents resilient to PSU showed significant larger grey matter volumes in the bilateral cingulate gyrus compared with enduring polysubstance users and controls at ages 19 and 14 (p<0.05 corrected) but no difference in fractional anisotropy. The larger cingulate volumes and personality trait "openness to experience" were the best precursors of resilience to PSU. Early in adolescence, a larger cingulate gyrus differentiated adolescents resilient to PSU, and this feature was critical in predicting this outcome. This study encourages further research into the neurobiological bases of resilience to addictive behaviors.

Irregular sleep habits, regional grey matter volumes, and psychological functioning in adolescents.

Changing sleep rhythms in adolescents often lead to sleep deficits and a delay in sleep timing between weekdays and weekends. The adolescent brain, and in particular the rapidly developing structures involved in emotional control, are vulnerable to external and internal factors. In our previous study in adolescents at age 14, we observed a strong relationship between weekend sleep schedules and regional medial prefrontal cortex grey matter volumes. Here, we aimed to assess whether this relationship remained in this group of adolescents of the general population at the age of 16 (n = 101; mean age 16.8 years; 55% girls). We further examined grey matter volumes in the hippocampi and the amygdalae, calculated with voxel-based morphometry. In addition, we investigated the relationships between sleep habits, assessed with self-reports, and regional grey matter volumes, and psychological functioning, assessed with the Strengths and Difficulties Questionnaire and tests on working memory and impulsivity. Later weekend wake-up times were associated with smaller grey matter volumes in the medial prefrontal cortex and the amygdalae, and greater weekend delays in wake-up time were associated with smaller grey matter volumes in the right hippocampus and amygdala. The medial prefrontal cortex region mediated the correlation between weekend wake up time and externalising symptoms. Paying attention to regular sleep habits during adolescence could act as a protective factor against the emergence of psychopathology via enabling favourable brain development.

Association between the timing of consultation-liaison psychiatry interventions and the length of stay in general hospital.

BACKGROUND: Psychiatric comorbidities are frequent in patients admitted in general hospital and are associated with greater lengths of stay (LOS). Early consultation-liaison psychiatry (CLP) interventions may reduce the LOS but previous studies were underpowered to allow subgroup analyses and have generally not considered the severity of the condition for which patients were admitted ('disease severity'). AIMS: To investigate the association between the timing of CLP interventions and LOS in a general hospital. METHOD: We retrospectively included 4500 consecutive patients admitted in non-psychiatric wards of a university hospital between 2008 and 2016 who had a first CLP intervention. We used general linear models to examine the association between the referral time, defined as log(days before the consultation)/log(LOS), and log(LOS), adjusting for age, gender, year of admission, place of residence, main psychiatric diagnosis, admission to the intensive care unit (ICU), main physical condition and disease severity. RESULTS: Referral time was associated with log(LOS) (ß = 0.31; P <0.001), notably for older patients (ß = 0.43; P <0.001) and those admitted to the ICU (ß = 0.50; P <0.001), but not for those with psychotic disorders (ß = -0.20; P = 0.10). The association was confirmed when considering the expected LOS for each patient. For instance, for an expected LOS of 10 days, a CLP intervention on day 3 compared with day 6 was associated with a reduction of the actual LOS of 2.4 days. CONCLUSIONS: Earlier CLP interventions were associated with a clinically significant shorter LOS in a large population even after adjusting for disease severity. Early CLP interventions may have benefits for both patients and health-related costs.

Depression, antidepressants and low hemoglobin level in the Paris Prospective Study III: A cross-sectional analysis.

Anemia is known to be associated with depression both in community and clinical populations. However, it is still unknown if this association depends or not on antidepressant intake. We investigated the respective association of depression and antidepressant intake with low hemoglobin level in a large community-based cohort. In 8640 volunteers aged 50 to 75 recruited between June 2008 and June 2012 in Paris (France), we assessed hemoglobin levels (g/dl), depressive symptoms and antidepressant intake. We examined the association of both depression and antidepressant intake with hemoglobin level, adjusting for numerous socio-demographic and health variables. We also assessed the association with specific antidepressant classes. Depression and antidepressant intake were independently associated with lower hemoglobin level (ß = -0.074; p = .05 and ß = -0.100; p = .02 respectively in the fully-adjusted model). Regarding antidepressant classes, selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) intake were associated with lower hemoglobin level (ß = -0.11; p = .01). To conclude, both depression and antidepressant intake were associated with lower hemoglobin level. In particular, as SSRI or SNRIs intake was also related to lower hemoglobin level, these classes should be used with caution in depressed individuals at risk for anemia.

Sex effects on structural maturation of the limbic system and outcomes on emotional regulation during adolescence.

Though adolescence is a time of emerging sex differences in emotions, sex-related differences in the anatomy of the maturing brain has been under-explored over this period. The aim of this study was to investigate whether puberty and sexual differentiation in brain maturation could explain emotional differences between girls and boys during adolescence. We adapted a dedicated longitudinal pipeline to process structural and diffusion images from 335 typically developing adolescents between 14 and 16 years. We used voxel-based and Regions of Interest approaches to explore sex and puberty effects on brain and behavioral changes during adolescence. Sexual differences in brain maturation were characterized by amygdala and hippocampal volume increase in boys and decrease in girls. These changes were mediating the sexual differences in positive emotional regulation as illustrated by positive attributes increase in boys and decrease in girls. Moreover, the differential maturation rates between the limbic system and the prefrontal cortex highlighted the delayed maturation in boys compared to girls. This is the first study to show the sex effects on the differential cortico/subcortical maturation rates and the interaction between sex and puberty in the limbic system maturation related to positive attributes, reported as being protective from emotional disorders.

Suicide attempts by jumping and length of stay in general hospital: A retrospective study of 225 patients.

OBJECTIVE: Violent suicide attempts, such as jumping from a height, frequently lead to hospitalization in general hospital with high length of stay (LOS). We investigated features associated with LOS in this context. METHODS: We retrospectively included all patients admitted after suicide attempts by jumping in non-psychiatric wards of a university hospital between 2008 and 2016. Several socio-demographic and clinical data were collected, including psychiatric diagnoses, coded with the International Classification of Diseases-10th Revision. We used general linear models to identify factors associated with LOS. RESULTS: Among 225 patients (125 men; mean age ±â€¯sd: 37.5 ±â€¯15.4 years), several clinical factors were independently associated with a longer LOS: number of injuries (ß = 8.2 p < .001), external fixator (ß = 18.1 p = .01), psychotic disorder (ß = 14.6 p = .02) and delirium (ß = 16.6 p = .005). Admission in psychiatric ward at discharge tended to be associated with lower LOS (ß = -15.3 p = .07). CONCLUSION: In patients admitted in non-psychiatric wards after suicide attempt by jumping, the presence of a psychotic disorder may increase LOS by several days, and indirectly costs of hospitalization, to a similar extent of non-psychiatric factors. The association of transfer in psychiatric ward with lower LOS suggests that the psychiatric disorder might interfere with medical care.

Depression, Cognitive Functions, and Impaired Functioning in Middle-Aged Adults From the CONSTANCES Cohort.

OBJECTIVE: This large-scale population-based prospective study examined the association between depressive symptoms and cognitive performance at baseline with later functioning in middle-aged adults. METHODS: The Center for Epidemiologic Studies Depression Scale, the Digit Symbol Substitution Test (DSST), the Trail Making Test B (TMT-B), and the Semantic Verbal Fluency test (SVF) were completed at baseline by 7,426 participants aged ≥ 45 years from February 2012 to December 2013. Role limitations and social functioning were later assessed with the second version of the 12-Item Short Form Health Survey. The association between depressive symptoms and cognitive performance at baseline with functioning at follow-up was examined using general linear models and mediation analyses including sex, age, education, alcohol intake, and cannabis use as covariates. RESULTS: Altered functioning at follow-up was predicted by depressive symptoms (ß per standard deviation [95% confidence intervals]: -1.10 [-1.16 to -1.03] and -1.02 [-1.08, -0.96] for role limitations and social functioning, respectively) and DSST, TMT-B, and SVF performance (for role limitations: 0.11 [0.09 to 0.14], -0.11 [-0.13 to -0.08], and 0.03 [0.01 to 0.06], respectively; for social functioning: 0.10 [0.07 to 0.12], -0.08 [-0.11 to -0.06], and 0.04 [0.01 to 0.05], respectively) at baseline. Depressive symptoms were associated with poorer cognitive performance at baseline (-0.19 [-0.25 to -0.13], 0.15 [0.08 to 0.21], and -0.11 [-0.17 to -0.04], respectively). Cognitive performance accounted for only 0.3%-1.4% of the relationship between depressive symptoms and functioning. In contrast, depressive symptoms accounted for 19.5%-43.7% of the association between cognitive performance and functioning. CONCLUSIONS: In middle-aged adults from the general population, cognitive impairment is unlikely to substantially explain the association between depressive symptoms and later role limitations and social functioning.

Early Variations in White Matter Microstructure and Depression Outcome in Adolescents With Subthreshold Depression.

OBJECTIVE: White matter microstructure alterations have recently been associated with depressive episodes during adolescence, but it is unknown whether they predate depression. The authors investigated whether subthreshold depression in adolescence is associated with white matter microstructure variations and whether they relate to depression outcome. METHOD: Adolescents with subthreshold depression (N=96) and healthy control subjects (N=336) drawn from a community-based cohort were compared using diffusion tensor imaging and whole brain tract-based spatial statistics (TBSS) at age 14 to assess white matter microstructure. They were followed up at age 16 to assess depression. Probabilistic tractography was used to reconstruct white matter streamlines spreading from the regions identified in the TBSS analysis and along bundles implicated in emotion regulation, the uncinate fasciculus and the cingulum. The authors searched for mediating effects of white matter microstructure on the relationship between baseline subthreshold depression and depression at follow-up, and then explored the specificity of the findings. RESULTS: Lower fractional anisotropy (FA) and higher radial diffusivity were found in the anterior corpus callosum in the adolescents with subthreshold depression. Tractography analysis showed that they also had lower FA in the right cingulum streamlines, along with lower FA and higher mean diffusivity in tracts connecting the corpus callosum to the anterior cingulate cortex. The relation between subthreshold depression at baseline and depression at follow-up was mediated by FA values in the latter tracts, and lower FA values in those tracts distinctively predicted higher individual risk for depression. CONCLUSIONS: Early FA variations in tracts projecting from the corpus callosum to the anterior cingulate cortex may denote a higher risk of transition to depression in adolescents.

Cardiovascular risk goes up as your mood goes down: Interaction of depression and socioeconomic status in determination of cardiovascular risk in the CONSTANCES cohort.

BACKGROUND: Recent evidence suggests that the association of psychological variables with the risk of coronary heart disease (CHD) might depend upon socioeconomic status (SES). However, it is unclear whether the association between depressive symptoms and CHD risk might differ according to three SES indicators (education, occupational status and household monthly income). METHODS: Among 34,836 working participants of the French CONSTANCES cohort (16,221 men, mean age [SD]: 44.0 [10.4] years) without history of cardiovascular disease, depressive symptoms were assessed with the Center of Epidemiologic Studies Depression scale (CES-D). The Framingham risk equation calibrated to the French population estimated the participant's 10-year risk of CHD. Associations between depressive symptoms and CHD risk were estimated using linear regression models in SES strata. RESULTS: The estimated 10-year risk of CHD was 16.9% in men and 1.8% in women. In men, the increased CHD risk in those with (versus without) depressive symptoms was more pronounced as occupational status decreased, being 0.65% (-0.57; 1.88), 1.58% (0.50; 2.66) and 3.19% (1.30; 5.07) higher in individuals of high, medium and low occupational status, respectively (p for interaction: 0.01). In contrast, effect modification by education or household income was less evident, despite similar trends. In women, no effect modification was found whatever the SES indicator. CONCLUSIONS: Depressive symptoms and 10-year estimated CHD risk were more tightly linked in individuals of lower SES, at least in men. Occupational status was the SES indicator that displays the most obvious effect modification on this association.

Ketamine Use for Suicidal Ideation in the General Hospital: Case Report and Short Review.

Low-dose infusion of ketamine may have rapid antisuicide properties. Such a treatment may therefore be useful in the general hospital to prevent suicide in an environment that cannot be made safe enough. We report on the use of ketamine as an efficient, well-tolerated treatment for persistent suicidal ideation in a patient hospitalized in a general hospital after a severe suicide attempt. Based on data in the literature, we suggest that the benefit-risk ratio for ketamine use in such a context is highly favorable.

Sleep habits, academic performance, and the adolescent brain structure.

Here we report the first and most robust evidence about how sleep habits are associated with regional brain grey matter volumes and school grade average in early adolescence. Shorter time in bed during weekdays, and later weekend sleeping hours correlate with smaller brain grey matter volumes in frontal, anterior cingulate, and precuneus cortex regions. Poor school grade average associates with later weekend bedtime and smaller grey matter volumes in medial brain regions. The medial prefrontal - anterior cingulate cortex appears most tightly related to the adolescents' variations in sleep habits, as its volume correlates inversely with both weekend bedtime and wake up time, and also with poor school performance. These findings suggest that sleep habits, notably during the weekends, have an alarming link with both the structure of the adolescent brain and school performance, and thus highlight the need for informed interventions.

Neural correlates of three types of negative life events during angry face processing in adolescents.

Negative life events (NLE) contribute to anxiety and depression disorders, but their relationship with brain functioning in adolescence has rarely been studied. We hypothesized that neural response to social threat would relate to NLE in the frontal-limbic emotional regions. Participants (N = 685) were drawn from the Imagen database of 14-year-old community adolescents recruited in schools. They underwent functional MRI while viewing angry and neutral faces, as a probe to neural response to social threat. Lifetime NLEs were assessed using the 'distress', 'family' and 'accident' subscales from a life event dimensional questionnaire. Relationships between NLE subscale scores and neural response were investigated. Links of NLE subscales scores with anxiety or depression outcomes at the age of 16 years were also investigated. Lifetime 'distress' positively correlated with ventral-lateral orbitofrontal and temporal cortex activations during angry face processing. 'Distress' scores correlated with the probabilities of meeting criteria for Generalized Anxiety Disorder or Major Depressive Disorder at the age of 16 years. Lifetime 'family' and 'accident' scores did not relate with neural response or follow-up conditions, however. Thus, different types of NLEs differentially predicted neural responses to threat during adolescence, and differentially predicted a de novo internalizing condition 2 years later. The deleterious effect of self-referential NLEs is suggested.

Smoking and the Association Between Depressive Symptoms and Absolute Neutrophil Count in the Investigations Préventives et Cliniques Cohort Study.

OBJECTIVES: Depressive symptoms have been associated with chronic low-grade inflammation, including elevated neutrophil count. Smokers often have both high neutrophil count and depressive symptoms. Thus, smoking could explain the cross-sectional association between depressive symptoms and neutrophil count. METHODS: Total white blood cell count and subtypes, including absolute neutrophil, lymphocyte, monocyte, basophil, and eosinophil counts, were measured in 44,806 participants (28,534 men; mean [standard deviation] age = 38.9 [11.4] years), without a history of chronic disease or current medication. Depressive symptoms were assessed with the Questionnaire of Depression, Second Version, Abridged. Smoking status was self-reported and categorized in five classes. Sex, age, alcohol intake, self-rated health, body mass index, glycemia, physical activity, household composition, occupational status, and education were included as covariates. Associations were examined with general linear models and causal mediation analyses. RESULTS: After adjustment for all covariates except smoking, depressive symptoms were positively associated with neutrophil count only (ß = 5.83, standard error [SE] = 2.41, p = .014). After further adjustment for a semiquantitative measure of smoking, this association was no longer significant (ß = 2.40, SE = 2.36, p = .30). Causal mediation analyses revealed that smoking mediated the association (p < .001), accounting for 57% of its total variance. In contrast, depressive symptoms were negatively associated with lymphocyte count in fully adjusted model only (ß = -3.21, SE = 1.11, p = .004). CONCLUSIONS: Smoking may confound or mediate the association between depressive symptoms and neutrophil count. These results advocate for including an accurate measure of smoking in future studies addressing this association. When considering the link between depression and inflammation, one should not overlook the noxious effects of smoking.

Subthreshold depression and regional brain volumes in young community adolescents.

OBJECTIVE: Neuroimaging findings have been reported in regions of the brain associated with emotion in both adults and adolescents with depression, but few studies have investigated whether such brain alterations can be detected in adolescents with subthreshold depression, a condition at risk for major depressive disorder. In this study, we searched for differences in brain structure at age 14 years in adolescents with subthreshold depression and their relation to depression at age 16 years. METHOD: High-resolution structural magnetic resonance imaging was used to assess adolescents with self-reported subthreshold depression (n = 119) and healthy control adolescents (n = 461), all recruited from a community-based sample. Regional gray and white matter volumes were compared across groups using whole-brain voxel-based morphometry. The relationship between subthreshold depression at baseline and depression outcome was explored using causal mediation analyses to search for mediating effects of regional brain volumes. RESULTS: Adolescents with subthreshold depression had smaller gray matter volume in the ventromedial prefrontal and rostral anterior cingulate cortices and caudates, and smaller white matter volumes in the anterior limb of internal capsules, left forceps minor, and right cingulum. In girls, but not in boys, the relation between subthreshold depression at baseline and high depression score at follow-up was mediated by medial-prefrontal gray matter volume. CONCLUSION: Subthreshold depression in early adolescence might be associated with smaller gray and white matter volumes in regions of the frontal-striatal-limbic affective circuit, and the occurrence of depression in girls with subthreshold depression might be influenced by medial-prefrontal gray matter volume. However, these findings should be interpreted with caution because of the limitations of the clinical assessment methods.

The Brain's Response to Reward Anticipation and Depression in Adolescence: Dimensionality, Specificity, and Longitudinal Predictions in a Community-Based Sample.

OBJECTIVE: The authors examined whether alterations in the brain's reward network operate as a mechanism across the spectrum of risk for depression. They then tested whether these alterations are specific to anhedonia as compared with low mood and whether they are predictive of depressive outcomes. METHOD: Functional MRI was used to collect blood-oxygen-level-dependent (BOLD) responses to anticipation of reward in the monetary incentive task in 1,576 adolescents in a community-based sample. Adolescents with current subthreshold depression and clinical depression were compared with matched healthy subjects. In addition, BOLD responses were compared across adolescents with anhedonia, low mood, or both symptoms, cross-sectionally and longitudinally. RESULTS: Activity in the ventral striatum was reduced in participants with subthreshold and clinical depression relative to healthy comparison subjects. Low ventral striatum activation predicted transition to subthreshold or clinical depression in previously healthy adolescents at 2-year follow-up. Brain responses during reward anticipation decreased in a graded manner between healthy adolescents, adolescents with current or future subthreshold depression, and adolescents with current or future clinical depression. Low ventral striatum activity was associated with anhedonia but not low mood; however, the combined presence of both symptoms showed the strongest reductions in the ventral striatum in all analyses. CONCLUSIONS: The findings suggest that reduced striatal activation operates as a mechanism across the risk spectrum for depression. It is associated with anhedonia in healthy adolescents and is a behavioral indicator of positive valence systems, consistent with predictions based on the Research Domain Criteria.