Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
1.
Cereb Cortex ; 30(7): 4269-4280, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32215605

RESUMO

Early life stress (ELS) may accelerate frontoamygdala development related to socioemotional processing, serving as a potential source of resilience. Whether this circuit is associated with other proposed measures of accelerated development is unknown. In a sample of young adolescents, we examined the relations among ELS, frontoamygdala circuitry during viewing of emotional faces, cellular aging as measured by telomere shortening, and pubertal tempo. We found that greater cumulative severity of ELS was associated with stronger negative coupling between bilateral centromedial amygdala and the ventromedial prefrontal cortex, a pattern that may reflect more mature connectivity. More negative frontoamygdala coupling (for distinct amygdala subdivisions) was associated with slower telomere shortening and pubertal tempo over 2 years. These potentially protective associations of negative frontoamygdala connectivity were most pronounced in adolescents who had been exposed to higher ELS. Our findings provide support for the formulation that ELS accelerates maturation of frontoamygdala connectivity and provide novel evidence that this neural circuitry confers protection against accelerated biological aging, particularly for adolescents who have experienced higher ELS. Although negative frontoamygdala connectivity may be an adaptation to ELS, frontoamygdala connectivity, cellular aging, and pubertal tempo do not appear to be measures of the same developmental process.


Assuntos
Experiências Adversas da Infância , Envelhecimento/metabolismo , Tonsila do Cerebelo/diagnóstico por imagem , Senescência Celular , Córtex Pré-Frontal/diagnóstico por imagem , Adolescente , Envelhecimento/fisiologia , Envelhecimento/psicologia , Tonsila do Cerebelo/fisiopatologia , Criança , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiopatologia , Neuroimagem Funcional , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Puberdade , Encurtamento do Telômero
2.
Dev Sci ; 22(3): e12775, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30471167

RESUMO

Exposure to stress has been causally linked to changes in hippocampal volume (HV). Given that the hippocampus undergoes rapid changes in the first years of life, stressful experiences during this period may be particularly important in understanding individual differences in the development of the hippocampus. One hundred seventy-eight early adolescents (ages 9-13 years; 43% male) were interviewed regarding exposure to and age of onset of experiences of stress; the severity of each stressful event was rated by an objective panel. All participants underwent structural magnetic resonance imaging, from which HVs were automatically segmented. Without considering the age of onset for stressful experiences, there was a small but statistically significant negative association of stress severity with bilateral HV. When considering the age of onset, there was a moderate and significant negative association between stress severity during early childhood (through 5 years of age) and HV; there was no association between stress severity during later childhood (age 6 years and older) and HV. We provide evidence of a sensitive period through 5 years of age for the effects of life stress on HV in adolescence. It will be important in future research to elucidate how reduced HV stemming from early life stress may contribute to stress-related health outcomes.


Assuntos
Hipocampo/fisiologia , Tamanho do Órgão/fisiologia , Estresse Psicológico/fisiopatologia , Adolescente , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
3.
Dev Psychopathol ; 31(3): 1011-1022, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31064568

RESUMO

Early life stress (ELS) is a risk factor for the development of depression in adolescence; the mediating neurobiological mechanisms, however, are unknown. In this study, we examined in early pubertal youth the associations among ELS, cortisol stress responsivity, and white matter microstructure of the uncinate fasciculus and the fornix, two key frontolimbic tracts; we also tested whether and how these variables predicted depressive symptoms in later puberty. A total of 208 participants (117 females; M age = 11.37 years; M Tanner stage = 2.03) provided data across two or more assessment modalities: ELS; salivary cortisol levels during a psychosocial stress task; diffusion magnetic resonance imaging; and depressive symptoms. In early puberty there were significant associations between higher ELS and decreased cortisol production, and between decreased cortisol production and increased fractional anisotropy in the uncinate fasciculus. Further, increased fractional anisotropy in the uncinate fasciculus predicted higher depressive symptoms in later puberty, above and beyond earlier symptoms. In post hoc analyses, we found that sex moderated several additional associations. We discuss these findings within a broader conceptual model linking ELS, emotion dysregulation, and depression across the transition through puberty, and contend that brain circuits implicated in the control of hypothalamic-pituitary-adrenal axis function should be a focus of continued research.


Assuntos
Depressão/psicologia , Hidrocortisona/análise , Puberdade/psicologia , Estresse Psicológico/psicologia , Adolescente , Depressão/fisiopatologia , Emoções/fisiologia , Feminino , Lobo Frontal/diagnóstico por imagem , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Límbico/diagnóstico por imagem , Masculino , Rede Nervosa/diagnóstico por imagem , Sistema Hipófise-Suprarrenal/fisiopatologia , Puberdade/fisiologia , Saliva/química , Estresse Psicológico/fisiopatologia , Substância Branca/diagnóstico por imagem
4.
Dev Sci ; 21(3): e12568, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28557196

RESUMO

Adolescence is a period characterized by continued improvements in inhibitory control, and this persisting immaturity is believed to interact with affective/motivational behavior to generate the impulsive and risk-taking behavior evidenced at this time. Puberty is a central event of adolescence that has been shown to influence affective/motivational behavior. However, despite plausible mechanisms by which puberty might influence inhibitory control, researchers have yet to test this possibility rigorously. Thus, we designed a study to examine the unique role of pubertal maturation, independent of age, in the development of inhibitory control. In order to minimize age-related variability while maximizing pubertal status variability, we recruited 78 participants (34 F) whose ages narrowly spanned the mean age of gonadarche for each sex (F: ages 11-13, M: ages 12-14). Two complementary measures were used to assess pubertal status: (1) circulating blood serum testosterone and estradiol levels reflecting internal manifestations of pubertal maturation, and (2) Tanner staging by a trained nurse reflecting pubertal maturation's external manifestations. Inhibitory control was assessed using the antisaccade task, and findings were adjusted for the potential effect of age. Results revealed no association between testosterone levels and error rates or response latencies in either sex. In girls, estradiol levels were not associated with error rates, but were associated with faster response latencies. There was similarly no association between Tanner status and error rates, although girls in more advanced pubertal stages showed faster response latencies. Power analyses indicate that findings of a lack of association did not reflect limited statistical power. Thus, in a study designed to isolate the effects of pubertal maturation independent of age, both external and internal indices of pubertal maturation converged to indicate that age-related improvements in cold antisaccade performance are independent of pubertal maturation.


Assuntos
Fixação Ocular/fisiologia , Puberdade/fisiologia , Movimentos Sacádicos/fisiologia , Autocontrole , Maturidade Sexual/fisiologia , Adolescente , Criança , Estradiol/sangue , Feminino , Humanos , Masculino , Testosterona/sangue
5.
Dev Psychopathol ; 29(5): 1851-1864, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29162186

RESUMO

Early life stress (ELS) is a significant risk factor for the emergence of internalizing problems in adolescence. Beginning in adolescence, females are twice as likely as males to experience internalizing disorders. The present study was designed to examine sex differences in the association between ELS and internalizing problems in early pubertal adolescents, and whether and how corticolimbic function and connectivity may underlie these associations. Fifty-nine early pubertal males and 78 early pubertal females, ages 9-13 years (all Tanner Stage 3 or below) underwent functional magnetic resonance imaging as they performed an emotion label task that robustly interrogates corticolimbic function. Participants were also interviewed about their experience of ELS. Females exhibited a positive association between ELS and internalizing problems, whereas males exhibited no such association. Whole-brain and amygdala region of interest analyses indicated that whereas females exhibited a positive association between ELS and the ventrolateral prefrontal cortex during implicit emotion regulation, males showed no such association. Activation in these regions was positively associated with internalizing problems in females but not males; however, activation in these regions did not mediate the association between ELS and internalizing problems. Finally, both boys and girls exhibited an association between ELS and increased negative connectivity between the right ventrolateral prefrontal cortex and bilateral amygdala. Using a carefully characterized sample of early pubertal adolescents, the current study highlights important sex differences in the development of corticolimbic circuitry during a critical period of brain development. These sex differences may play a significant role in subsequent risk for internalizing problems.


Assuntos
Comportamento do Adolescente/psicologia , Emoções , Córtex Pré-Frontal/fisiopatologia , Autocontrole/psicologia , Estresse Psicológico/fisiopatologia , Adolescente , Tonsila do Cerebelo/diagnóstico por imagem , Criança , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Fatores de Risco , Caracteres Sexuais , Fatores Sexuais , Estresse Psicológico/diagnóstico por imagem , Estresse Psicológico/psicologia
6.
J Neurosci ; 33(46): 18109-24, 2013 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-24227721

RESUMO

Neuroimaging studies suggest that developmental improvements in inhibitory control are primarily supported by changes in prefrontal executive function. However, studies are contradictory with respect to how activation in prefrontal regions changes with age, and they have yet to analyze longitudinal data using growth curve modeling, which allows characterization of dynamic processes of developmental change, individual differences in growth trajectories, and variables that predict any interindividual variability in trajectories. In this study, we present growth curves modeled from longitudinal fMRI data collected over 302 visits (across ages 9 to 26 years) from 123 human participants. Brain regions within circuits known to support motor response control, executive control, and error processing (i.e., aspects of inhibitory control) were investigated. Findings revealed distinct developmental trajectories for regions within each circuit and indicated that a hierarchical pattern of maturation of brain activation supports the gradual emergence of adult-like inhibitory control. Mean growth curves of activation in motor response control regions revealed no changes with age, although interindividual variability decreased with development, indicating equifinality with maturity. Activation in certain executive control regions decreased with age until adolescence, and variability was stable across development. Error-processing activation in the dorsal anterior cingulate cortex showed continued increases into adulthood and no significant interindividual variability across development, and was uniquely associated with task performance. These findings provide evidence that continued maturation of error-processing abilities supports the protracted development of inhibitory control over adolescence, while motor response control regions provide early-maturing foundational capacities and suggest that some executive control regions may buttress immature networks as error processing continues to mature.


Assuntos
Comportamento do Adolescente/fisiologia , Encéfalo/crescimento & desenvolvimento , Gráficos de Crescimento , Inibição Neural/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Comportamento do Adolescente/psicologia , Adulto , Criança , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Estimulação Luminosa/métodos , Adulto Jovem
7.
Dev Cogn Neurosci ; 45: 100836, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32836077

RESUMO

Emotion processing is believed to dominate over other brain functions during adolescence, including inhibitory control. However, few studies have examined the neural underpinnings of affective states during cognitive control. Here, we characterized the brain in an affective state by cross-sectionally assessing age-related changes in amygdala background connectivity during an affective inhibitory control task. Participants completed an antisaccade (AS) fMRI task while affective auditory stimuli were presented, and a 5-minute resting state scan. Results showed that while adolescents reported similar arousal levels across emotional conditions, adults perceived negative sounds to be more "arousing" and performed better than adolescents in negative trials. Amygdala background connectivity showed age-related increases with brain regions related to attention and executive control, which were not evident during resting state. Together, results suggest that amygdala connectivity within an affective context is fairly low in mid-adolescence but much stronger in adulthood, supporting age-related improvements in inhibitory control within an affective state. These findings suggest limitations during adolescence in differentiating between the arousing effects of various emotions, potentially undermining the ability to optimally engage inhibitory control. Furthermore, the age-related fMRI findings suggest that low amygdala connectivity to brain areas involved in executive control may underlie these limited abilities during adolescence.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Encéfalo/fisiopatologia , Cognição/fisiologia , Emoções/fisiologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Adulto Jovem
8.
Hum Brain Mapp ; 30(1): 163-74, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18041741

RESUMO

In this report, we present the first regional quantitative analysis of age-related differences in the heritability of cortical thickness using anatomic MRI with a large pediatric sample of twins, twin siblings, and singletons (n = 600, mean age 11.1 years, range 5-19). Regions of primary sensory and motor cortex, which develop earlier, both phylogenetically and ontologically, show relatively greater genetic effects earlier in childhood. Later developing regions within the dorsal prefrontal cortex and temporal lobes conversely show increasingly prominent genetic effects with maturation. The observation that regions associated with complex cognitive processes such as language, tool use, and executive function are more heritable in adolescents than children is consistent with previous studies showing that IQ becomes increasingly heritable with maturity(Plomin et al. 1997: Psychol Sci 8:442-447). These results suggest that both the specific cortical region and the age of the population should be taken into account when using cortical thickness as an intermediate phenotype to link genes, environment, and behavior.


Assuntos
Envelhecimento/genética , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/genética , Padrões de Herança/genética , Inteligência/genética , Adolescente , Fatores Etários , Criança , Pré-Escolar , Cognição/fisiologia , Meio Ambiente , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Motor/anatomia & histologia , Córtex Motor/crescimento & desenvolvimento , Fenótipo , Córtex Pré-Frontal/anatomia & histologia , Córtex Pré-Frontal/crescimento & desenvolvimento , Córtex Somatossensorial/anatomia & histologia , Córtex Somatossensorial/crescimento & desenvolvimento , Lobo Temporal/anatomia & histologia , Lobo Temporal/crescimento & desenvolvimento , Adulto Jovem
9.
J Affect Disord ; 245: 545-552, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30439679

RESUMO

BACKGROUND: Suicidal ideation (SI) is an important predictor of suicide attempt, yet SI is difficult to predict. Given that SI begins in adolescence when brain networks are maturing, it is important to understand associations between network functioning and changes in severity of SI. METHODS: Thirty-three depressed adolescents were administered the Columbia-Suicide Severity Rating Scale to assess SI and completed resting-state fMRI at baseline (T1) and 6 months later (T2). We computed coherence in the executive control (ECN), default mode (DMN), salience (SN), and non-relevant noise networks and then examined the association between changes in brain network coherence and changes in SI severity from T1 to T2. RESULTS: A greater reduction in severity of SI was associated with a stronger increase in SN coherence from T1 to T2. There were no associations between the other networks and SI. LIMITATIONS: We cannot generalize our findings to more psychiatrically diverse samples. More time-points are necessary to understand the trajectory of SI and SN coherence change. CONCLUSIONS: Our finding that reductions in SI are associated with increases in SN coherence extends previous cross-sectional results documenting a negative association between SI severity and SN coherence. The SN is involved in coordinating activation of ECN and DMN in response to salient information. Given this regulatory role of the SN, the association between SN coherence and SI suggests that adolescents with reduced SN coherence might more easily engage in harmful thoughts. Thus, the SN may be particularly relevant as a target for treatment applications in depressed adolescents.


Assuntos
Comportamento do Adolescente/psicologia , Encéfalo/fisiologia , Depressão/psicologia , Função Executiva/fisiologia , Ideação Suicida , Adolescente , Mapeamento Encefálico/métodos , Estudos Transversais , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos
10.
J Abnorm Child Psychol ; 47(8): 1401-1408, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30847667

RESUMO

Research with community samples suggests that non-affective features of families, such as the amount of time parents and adolescents spend together, affect depressive symptoms in adolescents. It is possible, however, that spending time with parents not only protects against the onset of depressive symptoms, but also reduces symptoms in adolescents who are already depressed. The current study was designed to test this formulation while also examining whether affective dimensions of family functioning - specifically parental warmth - accounted for or moderated observed associations. Finally, we tested the reverse direction of the associations, examining whether greater severity of depression in adolescents results in parents spending less time with them. Forty-one adolescents (ages 14 to 17 years) who met criteria for a current major depressive episode participated in the present study with one parent. Once each month for six time points, dyads completed reports of depressive symptoms and the amount of time parents and adolescents spent with each other. Participants also completed measures of parental warmth. Results of lagged multilevel modeling indicated that spending more time with a parent predicted fewer depressive symptoms in adolescents at the following assessment relative to their mean; in contrast, greater severity of depressive symptoms did not predict spending less time with a parent at the following assessment. In contrast, parental warmth did not account for or moderate the association between time together and depressive symptoms. These results suggest that non-affective dimensions of family life, specifically spending more time with parents, have beneficial effects on depressive symptoms in adolescents diagnosed with depression.


Assuntos
Transtorno Depressivo Maior/fisiopatologia , Relações Pais-Filho , Adolescente , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fatores de Tempo
11.
J Affect Disord ; 249: 26-34, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30743019

RESUMO

BACKGROUND: Major Depressive Disorder (MDD) is characterized by aberrant resting-state functional connectivity (FC) in anterior cingulate regions (e.g., subgenual anterior cingulate [sgACC]) and by negative emotional functioning that is inflexible or resistant to change. METHODS: MDD (N = 33) and control (CTL; N = 31) adults completed a resting-state scan, followed by a smartphone-based Experience Sampling Methodology (ESM) protocol surveying 10 positive and negative emotions 5 times per day for 21 days. We used multilevel modeling to assess moment-to-moment emotional inflexibility (i.e., strong temporal connections between emotions). We examined group differences in whole-brain FC analysis of bilateral sgACC, and then examined associations between emotional experiences and the extracted FC values within each group. RESULTS: As predicted, MDDs had inflexibility in sadness and avoidance (p < .001, FDR-corrected p < .05), indicating that these emotional experiences persist in depression. MDDs showed weaker FC between the right sgACC and pregenual/dorsal anterior cingulate (pg/dACC) than did CTLs (FWE-corrected, voxelwise p = .01). Importantly, sgACC-pg/dACC FC predicted sadness inflexibility in both MDDs (p = .046) and CTLs (p = .033), suggesting that sgACC FC is associated with day-to-day negative emotions. LIMITATIONS: Other maladaptive behaviors likely also affect the flexibility of negative emotions. We cannot generalize our finding of a positive relation between sgACC FC and inflexibility of sadness to individuals with more chronic depression or who have recovered from depression. CONCLUSIONS: Our preliminary findings suggest that connections between portions of the ACC contribute to the persistence of negative emotions and are important in identifying a brain mechanism that may underlie the maintenance of sadness in daily life.


Assuntos
Transtorno Depressivo Maior/fisiopatologia , Emoções/fisiologia , Giro do Cíngulo/fisiopatologia , Adolescente , Adulto , Encéfalo/fisiopatologia , Mapeamento Encefálico , Depressão/psicologia , Avaliação Momentânea Ecológica , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Tristeza , Inquéritos e Questionários , Adulto Jovem
12.
J Abnorm Child Psychol ; 47(2): 199-207, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29774495

RESUMO

Despite the high prevalence and substantial costs of early life stress (ELS), the mechanisms through which ELS confers risk for psychopathology are poorly understood, particularly among youth who are in an earlier stage of the transition through puberty. We sought to advance our understanding of the link between ELS and psychopathology by testing whether rumination mediates the relation between ELS and symptoms of psychopathology in youth in the early stages of puberty, and whether sex moderates this mediation. We assessed levels of ELS, both brooding and reflection subtypes of rumination, and internalizing and externalizing symptoms in 170 youth in the early stages of puberty (56% girls) ages 9-13 years. Brooding, but not reflection, mediated the relation between ELS and both internalizing and externalizing symptoms. Importantly, however, sex moderated the relation among ELS, brooding, and symptoms. Specifically, brooding mediated the relation between ELS and both internalizing and externalizing symptoms for girls, but not for boys. Findings support the formulation that brooding is a mechanism linking ELS to multiple forms of behavioral and emotional problems exclusively in girls in the early stages of puberty.


Assuntos
Experiências Adversas da Infância , Sintomas Comportamentais/fisiopatologia , Ruminação Cognitiva/fisiologia , Estresse Psicológico/fisiopatologia , Adolescente , Criança , Feminino , Humanos , Masculino , Modelos Psicológicos , Fatores Sexuais
13.
Dev Cogn Neurosci ; 30: 41-50, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29275097

RESUMO

Children from lower-SES families exhibit smaller hippocampal volume than do their higher-SES peers. Few studies, however, have compared hippocampal developmental trajectories as a function of SES. Thus, it is unclear whether initial rank-order stability is preserved, or whether volumes diverge/converge over the course of adolescence. In a sample of 101 girls ages 10-24 years, we examined the longitudinal association between family income and parental education, proxies for SES, and changes in hippocampal volume. Hippocampal volume was obtained using MRI; using mixed modeling, we examined the effects of income and education on hippocampal volume across age. As expected, changes in volume were non-linear across development. Further, trajectories diverged in mid-adolescence, with lower-income girls exhibiting reductions in hippocampal volume. Maximal income-related differences were observed at 18 years, and trajectories converged thereafter. This interaction remained significant when accounting for maternal hippocampal volume, suggesting a unique contribution of environment over potential heritable differences. In contrast, the association between parental education and offspring hippocampal volume appeared to be stable across adolescence, with higher levels of parental education predicting consistently larger hippocampal volume. These findings constitute preliminary evidence that girls from lower-income homes exhibit unique trajectories of hippocampal growth, with differences most evident in late adolescence.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Hipocampo/diagnóstico por imagem , Hipocampo/fisiologia , Renda/tendências , Relações Mãe-Filho/psicologia , Adolescente , Adulto , Criança , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/psicologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Pais/psicologia , Fatores de Tempo , Adulto Jovem
14.
J Affect Disord ; 226: 92-99, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-28968564

RESUMO

BACKGROUND: Suicidal ideation rates rise precipitously in adolescence, contributing to risk for attempts. Although researchers are beginning to explore the brain basis of attempts in depressed adolescents, none have focused on the basis of ideation, which has implications for prevention. This study examined the association between intrinsic neural network coherence and the severity of suicidal ideation in depressed adolescents. METHODS: Forty adolescents diagnosed with Major Depressive Disorder were administered the Columbia-Suicide Severity Rating Scale and underwent resting-state fMRI. We quantified within-network coherence in the executive control (ECN), default mode (DMN), and salience (SN) networks, and in a non-relevant network consisting of noise signal. We associated coherence in each of these networks with the greatest lifetime severity of suicidal ideation experienced, covarying for motion, age of depression onset, and severity of current depressive and anxious symptoms. RESULTS: Lower coherence in the left ECN, anterior DMN, and SN were independently associated with greater lifetime severity of suicidal ideation. When including all three significant networks and covariates in a single model, only the left ECN significantly predicted suicidal ideation. LIMITATION: Studies with a larger sample size are needed to verify our findings. CONCLUSIONS: Our finding of hypoconnectivity in multiple networks extends emerging evidence for hypoconnectivity in adolescent suicidality and is consistent with theoretical conceptualizations of suicidal ideation as a complex set of cognitions associated with cognitive control, self-referential thinking, and processing salient information. While multiple networks could be targets for effective early interventions, those targeting ECN functionality (cognitive control) may be particularly beneficial.


Assuntos
Comportamento do Adolescente/psicologia , Transtorno Depressivo Maior/psicologia , Ideação Suicida , Tentativa de Suicídio/psicologia , Suicídio/psicologia , Adolescente , Depressão , Função Executiva , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Fatores de Risco , Pensamento
15.
Soc Cogn Affect Neurosci ; 13(11): 1215-1224, 2018 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-30256980

RESUMO

Suicidal ideation (SI), a potent risk factor for suicide attempts, increases in adolescence. While alterations in dopaminergic functioning have been implicated in suicidal acts-particularly in adults-we do not know whether morphological alterations in dopamine-rich regions of the brain, such as the striatum, are vulnerability factors for the emergence of SI in adolescents. At baseline, a community sample of 152 adolescents (89 female; mean age: 11.41 ± 1.01 years) completed a magnetic resonance imaging (MRI) scan that was used to estimate gray matter volumes (GMVs) of three striatal structures: caudate, nucleus accumbens and putamen. At a 24 month follow-up session, participants completed a self-report measure of SI frequency [Suicidal Ideation Questionnaire (SIQ)] and the death version of the Implicit Association Test (IAT). Robust linear regression models were conducted to predict SIQ and IAT scores from striatal GMV. Bilateral putamen and left caudate GMV significantly predicted IAT scores (all Ps < 0.03). No other associations were significant (all Ps > 0.05). Our finding of reduced dorsal striatal GMV predicting implicit SI may indicate that downstream dopaminergic dysfunction is implicated in the development of overt suicidal behaviors. Self-reported SI was not associated with striatal GMV, suggesting that biological correlates of suicide risk may correlate specifically with objective measurements of SI in adolescents.


Assuntos
Corpo Estriado/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Ideação Suicida , Adolescente , Núcleo Caudado/diagnóstico por imagem , Criança , Neurônios Dopaminérgicos , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Núcleo Accumbens/diagnóstico por imagem , Valor Preditivo dos Testes , Putamen/diagnóstico por imagem , Medição de Risco , Fatores Socioeconômicos
16.
Soc Cogn Affect Neurosci ; 12(2): 298-310, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27633394

RESUMO

Rumination, and particularly ruminative brooding, perpetuates dysphoric mood states and contributes to the emergence of depression. Studies of adults and older adolescents have characterized the association between rumination and intrinsic functional connectivity within default mode (DMN), salience (SN) and executive control (ECN) networks; we know little, however, about the brain network basis of rumination during early puberty, a sensitive period for network reorganization. 112 early puberty boys and girls completed resting-state scans, the Ruminative Response Scale, and the Youth Self-Report questionnaire. Using independent components analysis and dual regression, we quantified coherence for each individual in networks of interest (SN, ECN, DMN) and in non-relevant networks (motor, visual) in which we predicted no correlations with behavioral measures. Boys and girls did not differ in levels of rumination or internalizing symptoms, or in coherence for any network. The relation between SN network coherence and rumination; however, and specifically ruminative brooding, was moderated by sex: greater SN coherence was associated with higher levels of brooding in girls but not in boys. Further, in girls, brooding mediated the relation between SN coherence and internalizing symptoms. These results point to coherence within the SN as a potential neurodevelopmental marker of risk for depression in early pubertal girls.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Função Executiva/fisiologia , Neuroimagem Funcional , Imageamento por Ressonância Magnética , Rede Nervosa/fisiopatologia , Puberdade/fisiologia , Puberdade/psicologia , Comportamento Estereotipado/fisiologia , Pensamento/fisiologia , Adolescente , Mapeamento Encefálico/métodos , Criança , Transtorno Depressivo/fisiopatologia , Transtorno Depressivo/psicologia , Feminino , Giro do Cíngulo/fisiopatologia , Humanos , Masculino
17.
Soc Cogn Affect Neurosci ; 12(9): 1460-1469, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28460088

RESUMO

Previous research suggests that exposure to early life stress (ELS) affects the structural integrity of the uncinate fasciculus (UF), a frontolimbic white matter tract that undergoes protracted development throughout adolescence. Adolescence is an important transitional period characterized by the emergence of internalizing psychopathology such as anxiety, particularly in individuals with high levels of stress sensitivity. We examined the relations among sensitivity to ELS, structural integrity of the UF, and anxiety symptoms in 104 early adolescents. We conducted structured interviews to assess exposure to ELS and obtained subjective and objective ratings of stress severity, from which we derived an index of ELS sensitivity. We also acquired diffusion MRI and conducted deterministic tractography to visualize UF trajectories and to compute measures of structural integrity from three distinct segments of the UF: frontal, insular, temporal. We found that higher sensitivity to ELS predicted both reduced fractional anisotropy in right frontal UF and higher levels of anxiety symptoms. These findings suggest that fibers in frontal UF, which are still developing throughout adolescence, are most vulnerable to the effects of heightened sensitivity to ELS, and that reduced structural integrity of frontal UF may underlie the relation between early stress and subsequent internalizing psychopathology.


Assuntos
Lobo Frontal/fisiopatologia , Sistema Límbico/fisiopatologia , Estresse Psicológico/fisiopatologia , Adolescente , Anisotropia , Ansiedade/fisiopatologia , Ansiedade/psicologia , Mapeamento Encefálico , Criança , Imagem de Tensor de Difusão , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Fibras Nervosas/fisiologia , Vias Neurais , Testes Neuropsicológicos , Substância Branca/fisiopatologia
18.
Psychoneuroendocrinology ; 77: 68-74, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28024271

RESUMO

Researchers have documented dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis in children and adolescents who experienced early life stress (ELS). The precise nature of this dysregulation, however, has been difficult to discern. In fact, both elevated and blunted patterns of diurnal cortisol regulation have been reported in children and adolescents exposed to greater ELS, including both reduced and heightened cortisol levels and change in cortisol across the day. These divergent findings may be due to developmental changes in the relation between ELS and HPA-axis functioning. The present study was designed to examine the role of puberty in the impact of the severity of ELS on the regulation of diurnal cortisol. Boys and girls (N=145) ages 9-13 years recruited from lower-risk communities completed an interview about their ELS experiences and at-home collection of diurnal cortisol. ELS experiences were objectively coded for severity, and children's level of pubertal development was measured using Tanner Staging. Multi-level piecewise mixed-effects models tested the effects of ELS severity and pubertal stage on cortisol levels at waking, the cortisol awakening response (CAR), and the daytime cortisol slope. While we found no significant interactive effects of pubertal stage and ELS severity on cortisol levels at waking or the daytime cortisol slope, findings indicated that pubertal stage interacted with ELS severity to predict the cortisol awakening response (CAR). Specifically, in earlier puberty, higher ELS was associated with a blunted CAR compared to lower ELS; in contrast, in later puberty, higher ELS was associated with a heightened CAR compared to lower ELS. Differences in the relation between ELS severity and the CAR were uniquely determined by puberty, and not by age. By considering and examining the role of puberty, the current study provides a developmental explanation for previous divergent findings of both blunted and heightened patterns of diurnal cortisol following ELS. These results indicate that careful attention should be given to children's pubertal status before drawing conclusions concerning the nature of diurnal cortisol dysregulation.


Assuntos
Ritmo Circadiano/fisiologia , Hidrocortisona/análise , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Puberdade/fisiologia , Estresse Psicológico/fisiopatologia , Adolescente , Criança , Feminino , Humanos , Masculino , Saliva/química
19.
Artigo em Inglês | MEDLINE | ID: mdl-28890942

RESUMO

BACKGROUND: Individuals with Major Depressive Disorder (MDD) are characterized by biases in attention to negative emotional material. While there is evidence that anomalous functioning in frontocingulate regions may underlie these biases, we know little about the neural correlates of negative emotional biases in depressed adolescents. METHODS: Eighteen adolescents diagnosed with MDD and 21 matched healthy control (CTL) adolescents underwent fMRI while performing an emotional distractor task. On each trial participants were presented with task-relevant house pairs and task-irrelevant face pairs. Participants indicated whether the house pairs were identical while ignoring the face pairs, which were either fearful, sad, or neutral. RESULTS: Despite equivalent behavioral performance (response time and accuracy) between groups, adolescents with MDD exhibited greater activation in frontocingulate regions, including dorsal anterior cingulate cortex (dACC) and inferior frontal gyrus/middle frontal gyrus (IFG/MFG), and occipitoparietal regions, including lateral occipital cortex and superior parietal lobule when ignoring fearful versus neutral faces. Response times to these trial conditions also correlated negatively with activation in IFG/MFG and lateral occipital cortex suggesting these regions are recruited in order to effectively ignore emotional distractors. Groups did not differ when ignoring sad versus neutral faces or fearful versus sad faces. CONCLUSIONS: Adolescents with MDD recruit both cognitive control and visual attention regions to a greater degree than do CTL adolescents, reflecting greater cognitive demand when downregulating threat-related stimuli.

20.
J Abnorm Psychol ; 124(4): 850-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26595472

RESUMO

Interactions between biological vulnerability and environmental adversity are central to the pathophysiology of depression. Given evidence that the hypothalamic-pituitary-adrenal (HPA) axis influences biological responses to environmental events, in the current longitudinal study the authors examined HPA-axis functioning, negative life events, and their interaction as predictors of the first onset of depression. At baseline, girls ages 9 to 14 years provided saliva samples to assess levels of diurnal cortisol production, quantified by total cortisol production (area under the curve with respect to ground; AUCg) and the cortisol awakening response (CAR). The authors then followed these participants until they reached age 18 in order to assess their subsequent experience of negative life events and the onset of a depressive episode. They found that the influence of negative life events on the subsequent onset of depression depended on HPA-axis functioning at baseline. Specifically, negative life events predicted the onset of depression in girls with higher levels of AUCg, but not in girls with lower levels of AUCg. In contrast, CAR did not predict the onset of depression either alone or in interaction with negative life events. These findings suggest that elevated total cortisol production in daily life potentiates susceptibility to environmental adversity and signals the need for early intervention.


Assuntos
Ritmo Circadiano/fisiologia , Depressão/diagnóstico , Transtorno Depressivo/diagnóstico , Hidrocortisona/análise , Acontecimentos que Mudam a Vida , Adolescente , Criança , Depressão/fisiopatologia , Depressão/psicologia , Transtorno Depressivo/fisiopatologia , Transtorno Depressivo/psicologia , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Estudos Longitudinais , Sistema Hipófise-Suprarrenal/fisiopatologia , Saliva/química , Meio Social , Estresse Psicológico/fisiopatologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA