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BACKGROUND: One in eight children experience early life stress (ELS), which increases risk for psychopathology. ELS, particularly neglect, has been associated with reduced responsivity to reward. However, little work has investigated the computational specifics of this disrupted reward response - particularly with respect to the neural response to Reward Prediction Errors (RPE) - a critical signal for successful instrumental learning - and the extent to which they are augmented to novel stimuli. The goal of the current study was to investigate the associations of abuse and neglect, and neural representation of RPE to novel and non-novel stimuli. METHODS: One hundred and seventy-eight participants (aged 10-18, M = 14.9, s.d. = 2.38) engaged in the Novelty task while undergoing functional magnetic resonance imaging. In this task, participants learn to choose novel or non-novel stimuli to win monetary rewards varying from $0 to $0.30 per trial. Levels of abuse and neglect were measured using the Childhood Trauma Questionnaire. RESULTS: Adolescents exposed to high levels of neglect showed reduced RPE-modulated blood oxygenation level dependent response within medial and lateral frontal cortices particularly when exploring novel stimuli (p < 0.05, corrected for multiple comparisons) relative to adolescents exposed to lower levels of neglect. CONCLUSIONS: These data expand on previous work by indicating that neglect, but not abuse, is associated with impairments in neural RPE representation within medial and lateral frontal cortices. However, there was no association between neglect and behavioral impairments on the Novelty task, suggesting that these neural differences do not necessarily translate into behavioral differences within the context of the Novelty task.
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Previous studies show aggression-related structural alterations in frontal and limbic brain regions. Most studies have focused on overall aggression, instead of its subtypes, and on specific regions instead of networks. This study aims to identify both brain networks and regions that are associated with reactive and proactive subtypes of aggression. Structural MRI data were collected from 340 adolescents (125 F/215 M) with a mean age of 16.29 (SD = 1.20). Aggression symptomology was indexed via the Reactive Proactive Aggression Questionnaire (RPQ). Freesurfer was used to estimate Cortical Volume (CV) from seven networks and regions within specific networks associated with aggression. Two multivariate analyses of covariance (MANCOVAs) were conducted on groups for low versus higher reactive and proactive RPQ scores. Our reactive aggression MANCOVA showed a main effect in CV [F(14,321) = 1.935, p = 0.022,ηp2 = 0.078] across all the 7-Networks. Unpacking this main effect revealed significant volumetric differences in the right Limbic Network (LN) (p = 0.029) and the Temporal Pole (p = 0.011), where adolescents in the higher reactive aggression group showed higher cortical volumes. Such findings are consistent with region/voxel-specific analyses that have associated atypical structure within the LN and reactive aggression. Moreover, the temporal pole is highly interconnected with regions important in the regulation and initiation of reactive aggression.
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BACKGROUND: Conduct disorder (CD) has been associated with dysfunction in reinforcement-based decision-making. Two forms of affective traits that reflect the components of CD severity are callous-unemotional (CU; reduced guilt/empathy) traits and irritability. The form of the reinforcement-based decision-making dysfunction with respect to CD and CU traits remains debated and has not been examined with respect to irritability in cases with CD. The goals of the current study were to determine the extent of dysfunction in differential (reward v. punishment) responsiveness in CD, and CU traits and irritability in participants with CD. METHODS: The study involved 178 adolescents [typically developing (TD; N = 77) and cases with CD (N = 101)]. Participants were scanned with fMRI during a passive avoidance task that required participants to learn to respond to (i.e. approach) stimuli that engender reward and refrain from responding to (i.e. passively avoid) stimuli that engender punishment. RESULTS: Adolescents with CD showed reduced differential reward-punishment responsiveness within the striatum relative to TD adolescents. CU traits, but not irritability, were associated with reduced differential reward-punishment responsiveness within the striatum, rostromedial, and lateral frontal cortices. CONCLUSIONS: The results suggest CD is associated with reduced differential reward-punishment responsiveness and the extent of this dysfunction in participants with CD is associated with the severity of CU traits but not irritability.
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Transtorno da Conduta , Adolescente , Humanos , Emoções , Punição , Empatia , Humor Irritável , RecompensaRESUMO
BACKGROUND: Adolescent substance use, externalizing and attention problems, and early life stress (ELS) commonly co-occur. These psychopathologies show overlapping neural dysfunction in the form of reduced recruitment of reward processing neuro-circuitries. However, it is unclear to what extent these psychopathologies show common v. different neural dysfunctions as a function of symptom profiles, as no studies have directly compared neural dysfunctions associated with each of these psychopathologies to each other. METHODS: In study 1, a latent profile analysis (LPA) was conducted in a sample of 266 adolescents (aged 13-18, 41.7% female, 58.3% male) from a residential youth care facility and the surrounding community to investigate substance use, externalizing and attention problems, and ELS psychopathologies and their co-presentation. In study 2, we examined a subsample of 174 participants who completed the Passive Avoidance learning task during functional magnetic resonance imaging to examine differential and/or common reward processing neuro-circuitry dysfunctions associated with symptom profiles based on these co-presentations. RESULTS: In study 1, LPA identified profiles of substance use plus rule-breaking behaviors, attention-deficit hyperactivity disorder, and ELS. In study 2, the substance use/rule-breaking profile was associated with reduced recruitment of reward processing and attentional neuro-circuitries during the Passive Avoidance task (p < 0.05, corrected for multiple comparisons). CONCLUSIONS: Findings indicate that there is reduced responsivity of striato-cortical regions when receiving outcomes on an instrumental learning task within a profile of adolescents with substance use and rule-breaking behaviors. Mitigating reward processing dysfunction specifically may represent a potential intervention target for substance-use psychopathologies accompanied by rule-breaking behaviors.
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Experiências Adversas da Infância , Transtornos Relacionados ao Uso de Substâncias , Humanos , Masculino , Adolescente , Feminino , Aprendizagem , Transtornos Relacionados ao Uso de Substâncias/diagnóstico por imagem , Recompensa , Atenção , Imageamento por Ressonância Magnética/métodosRESUMO
BACKGROUND: Widespread structural alterations have been shown to be implicated in individuals with generalized anxiety disorder (GAD). However, there have been inconsistent findings in cortical volume (CV) differences. Most structural neuroimaging studies looking at GAD used region-based approach with relatively small sample sizes, let alone be specific to adolescents with GAD. We believe this is the first study to look at CV measures using a network-based approach in a larger sample of adolescents with GAD. The goal of the current study was to focus on three different brain networks (i.e., Limbic, Frontoparietal, and Default Mode Network [DMN]) in adolescents with GAD. METHOD: The study involved 81 adolescents with GAD and 112 typically developing (TD) comparison individuals matched on age (15.98 and 15.63 respective means), sex (42F/39M and 45F/67M), and IQ (101.90 and 103.94 respective means). Participants underwent structural MRI. Freesurfer was used to estimate CV (both network-specific and region-specific within networks) and region-specific sub-cortical volume measures. Multivariate analysis of covariance (MANCOVA; with sex, age, IQ, and intracranial volume [ICV] as potential covariates) was used to estimate group differences. RESULTS: We found significantly lower CV for the DMN in adolescents with GAD, compared with TD individuals. Adolescents with GAD also showed significantly lower hemispheric mean CV of the default-mode regions (particularly the prefrontal and temporal regions) and the hippocampus, compared with TD individuals. CONCLUSION: The current findings suggest structural alterations in adolescents with GAD. These structural alterations will need to be addressed when implementing and developing treatments for patients with GAD.
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Transtornos de Ansiedade , Rede de Modo Padrão , Adolescente , Transtornos de Ansiedade/diagnóstico por imagem , Encéfalo , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética/métodos , NeuroimagemRESUMO
BACKGROUND: It has been proposed that individuals with generalized anxiety disorder (GAD) show dysfunctional computations related to approach-avoidance decision-making. However, few studies have examined the neural basis of this impairment, particularly in adolescents with GAD. The goal of the current study was to address this gap in the literature. METHOD: The study involved 51 adolescents with GAD and 51 typically developing (TD) comparison individuals matched on age (16.10 and 15.75 respective means), gender (30 F/21 M and 24 F/27 M), and IQ (103.20 and 103.18 respective means). Participants underwent functional magnetic resonance imaging during a passive avoidance task. RESULTS: We found a significant Group-by-Reinforcement interaction within reward-related brain regions including the caudate, putamen, mid cingulate/paracentral lobule, and superior and middle frontal gyrus. TD adolescents showed a greater differential response to reward versus punishment feedback within these regions relative to adolescents with GAD. In particular, this reflected reduced responses to rewards in the adolescents with GAD. There were no group differences in neural responses when making approach/avoidance responses. CONCLUSION: The results of this study suggest reduced differential responsiveness to reinforcement as a component of the pathophysiology seen in adolescents with GAD. This dysfunction likely underpins decision-making impairments that may exacerbate the participants' worry.
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Aprendizagem da Esquiva , Punição , Adolescente , Transtornos de Ansiedade , Encéfalo/diagnóstico por imagem , Tomada de Decisões , Humanos , Imageamento por Ressonância Magnética , RecompensaRESUMO
Trauma screening is an important element for providing trauma-informed services to youth in residential care. Unfortunately, lack of time and resources may deter clinicians from conducting trauma screening at intake. This study tested the psychometric properties of the Brief Trauma Symptom Screen for Youth (BTSSY), which could be used during intake into residential care. Participants included 572 youth, ages 10-18 years (M = 14.28 years, SD = 2.31), of whom 58.9% were boys, 78.7% were Caucasian, 51.7% were youth receiving services in residential care, 15.6% were youth with clinical needs, and 32.7% were typically developing youth from the local community. Participants completed the BTSSY; other questionnaires of psychopathology, childhood maltreatment, and symptomology of posttraumatic stress disorder (PTSD); and diagnostic interviews, which were conducted by licensed psychiatrists. The total BTSSY score had a good composite reliability (CR) of .80 and was valid based on a significant positive correlation, r = .64, with the UCLA PTSD-Reaction Index. The BTSSY score was also fair, area under the curve = .75, at detecting a diagnosis of PTSD from a psychiatrist. Significant group differences in the BTSSY scores were found between youth with a diagnosis of PTSD and the other two groups, with moderate-to-large effect sizes, ds = 0.73-1.22. Preliminary results indicated the BTSSY may be a useful screening tool for identifying youth at residential care intake who may need additional assessment for PTSD. Limitations and implications for future research and practice are discussed.
Spanish Abstracts by Asociación Chilena de Estrés Traumático (ACET) Psicometría de la escala breve de síntomas de trauma para jóvenes en atención residencial TAMIZAJE BREVE DE SÍNTOMAS DE TRAUMA PARA JOVENES La detección de los traumas es un elemento importante para proporcionar servicios informados en el trauma a los jóvenes en atención residencial. Desafortunadamente, la falta de tiempo y recursos puede impedir a los médicos realizar detección de traumas en el ingreso. Este estudio probó las propiedades psicométricas de la Escala Breve de Síntomas de Trauma para Jóvenes (BTSSY en su sigla en inglés), que podría usarse durante el ingreso a la atención residencial. Los participantes incluyeron 572 jóvenes, de 10 a 18 años (M = 14.28 años, DE = 2.31), de los cuales 58.9% eran niños, 78.7% eran caucásicos, 51.7% eran jóvenes que recibían servicios de atención residencial, 15.6% eran jóvenes con necesidades clínicas, y 32.7% eran jóvenes con desarrollo normativo de la comunidad local. Los participantes completaron el BTSSY; otros cuestionarios de psicopatología, maltrato infantil, y sintomatología del trastorno de estrés postraumático (TEPT); y entrevistas de diagnóstico, realizadas por psiquiatras calificados. El puntaje BTSSY total tuvo una buena confiabilidad compuesta (CR en su sigla en inglés) de .80 y fue válido en base a una correlación positiva significativa, r = .64, con el Índice de Reacción del TEPT de UCLA. El puntaje BTSSY también fue favorable, área bajo la curva = .75, al detectar un diagnóstico del TEPT de un psiquiatra. Se encontraron diferencias significativas entre los grupos en los puntajes BTSSY entre los jóvenes con diagnóstico del TEPT y los otros dos grupos, con tamaños del efecto moderados a grandes, ds = 0.73-1.22. Los resultados preliminares indicaron que el BTSSY puede ser una herramienta útil de detección para identificar a los jóvenes que reciben atención residencial y que pueden necesitar una evaluación adicional para el TEPT. Se discuten las limitaciones e implicaciones para futuras investigaciones y la práctica.
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Transtornos de Estresse Pós-Traumáticos/diagnóstico , Inquéritos e Questionários , Avaliação de Sintomas/métodos , Adolescente , Criança , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Psicometria , Reprodutibilidade dos Testes , Instituições Residenciais , Fatores SexuaisRESUMO
BACKGROUND: Internalizing and externalizing psychopathology typically present in early childhood and can have negative implications on general functioning and quality of life. Prior work has linked increased psychopathology symptoms with altered brain structure. Multivariate analysis such as partial least squares correlation can help identify patterns of covariation between brain regions and psychopathology symptoms. This study examined the relationship between gray matter volume (GMV) and psychopathology symptoms in adolescents with various psychiatric diagnoses. METHODS: Structural magnetic resonance imaging data were collected from 490 participants with various internalizing and externalizing diagnoses (197 female/293 male; age = 14.68 ± 2.35 years; IQ = 104.05 ± 13.11). Cortical and subcortical volumes were parcellated using the Desikan-Killiany atlas. Partial least squares correlation was used to identify multivariate linear relationships between GMV and the Strength and Difficulties Questionnaire difficulties domains (emotional, peer, conduct, and hyperactivity issues). Resampling approaches were used to determine significance (permutation test), stability (bootstrap resampling), and reproducibility (split-half resampling) of identified relationships. RESULTS: We found a significant, stable, and largely reproducible dimension that linked lower Strength and Difficulties Questionnaire scores (less impairment) across all difficulties domains with greater widespread GMV (singular value = 1.17, accounts for 87.1% of the covariance; p < .001). This dimension emphasized the relationship between lower conduct problems and greater GMV in frontotemporal regions. CONCLUSIONS: Our results indicate that the most significant and stable brain-behavior relationship in a transdiagnostic sample is a domain-general relationship, linking lower psychopathology symptom scores to greater global GMV. This finding suggests that a shared brain-behavior relationship may be present across adolescents with and without clinically significant psychopathology symptoms.
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Transtornos Mentais , Qualidade de Vida , Humanos , Masculino , Pré-Escolar , Feminino , Adolescente , Criança , Reprodutibilidade dos Testes , Encéfalo/patologia , Transtornos Mentais/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologiaRESUMO
BACKGROUND: Suicide is the second leading cause of death for adolescents in the United States. However, relatively little is known about the forms of atypical neuro-cognitive function that are correlates of suicidal ideation (SI). One form of cognitive/affective function that, when dysfunctional, is associated with SI is emotion regulation. However, very little work has investigated the neural correlates of emotion dysregulation in adolescents with SI. METHODS: Participants (N = 111 aged 12-18, 32 females, 31 [27.9%] reporting SI) were recruited shortly after their arrival at a residential care facility where they had been referred for behavioral and mental health problems. Daily reports of SI were collected during the participants' first 90-days in residential care. Participants were presented with a task-fMRI measure of emotion regulation - the Affective Number Stroop task shortly after recruitment. Participants were divided into two groups matched for age, sex and IQ based on whether they demonstrated SI. RESULTS: Participants who demonstrated SI showed increased recruitment of regions including dorsomedial prefrontal cortex/supplemental motor area and parietal cortex during task (congruent and incongruent) relative to view trials in the context of emotional relative to neutral distracters. CONCLUSIONS: Participants with SI showed increased recruitment of regions implicated in executive control during the performance of a task indexing automatic emotion regulation. Such data might suggest a relative inefficiency in the recruitment of these regions in individuals with SI.
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Regulação Emocional , Suicídio , Feminino , Humanos , Adolescente , Ideação Suicida , Emoções , Função ExecutivaRESUMO
Suicide is a leading cause of death in the United States. Historically, scientific inquiry has focused on psychological theory. However, more recent studies have started to shed light on complex biosignatures using MRI techniques, including task-based and resting-state functional MRI, brain morphometry, and diffusion tensor imaging. Here, we review recent research across these modalities, with a focus on participants with depression and Suicidal Thoughts and Behavior (STB). A PubMed search identified 149 articles specific to our population of study, and this was further refined to rule out more diffuse pathologies such as psychotic disorders and organic brain injury and illness. This left 69 articles which are reviewed in the current study. The collated articles reviewed point to a complex impairment showing atypical functional activation in areas associated with perception of reward, social/affective stimuli, top-down control, and reward-based learning. This is broadly supported by the atypical morphometric and diffusion-weighted alterations and, most significantly, in the network-based resting-state functional connectivity data that extrapolates network functions from well validated psychological paradigms using functional MRI analysis. We see an emerging picture of cognitive dysfunction evident in task-based and resting state fMRI and network neuroscience studies, likely preceded by structural changes best demonstrated in morphometric and diffusion-weighted studies. We propose a clinically-oriented chronology of the diathesis-stress model of suicide and link other areas of research that may be useful to the practicing clinician, while helping to advance the translational study of the neurobiology of suicide.
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INTRODUCTION: Depressive symptoms can emerge as early as childhood and may lead to adverse situations in adulthood. Studies have examined structural brain alternations in individuals with depressive symptoms, but findings remain inconclusive. Furthermore, previous studies have focused on adults or used a categorical approach to assess depression. The current study looks to identify grey matter volumes (GMV) that predict depressive symptomatology across a clinically concerning sample of adolescents. METHODS: Structural MRI data were collected from 338 clinically concerning adolescents (mean age = 15.30 SD=2.07; mean IQ = 101.01 SD=12.43; 132 F). Depression symptoms were indexed via the Mood and Feelings Questionnaire (MFQ). Freesurfer was used to parcellate the brain into 68 cortical regions and 14 subcortical regions. GMV was extracted from all 82 brain areas. Multiple linear regression was used to look at the relationship between MFQ scores and region-specific GMV parameter. Follow up regressions were conducted to look at potential effects of psychiatric diagnoses and medication intake. RESULTS: Our regression analysis produced a significant model (R2 = 0.446, F(86, 251) = 2.348, p < 0.001). Specifically, there was a negative association between GMV of the left parahippocampal (B = -0.203, p = 0.005), right rostral anterior cingulate (B = -0.162, p = 0.049), and right frontal pole (B = -0.147, p = 0.039) and a positive association between GMV of the left bank of the superior temporal sulcus (B = 0.173, p = 0.029). Follow up analyses produced results proximal to the main analysis. CONCLUSIONS: Altered regional brain volumes may serve as biomarkers for the development of depressive symptoms during adolescence. These findings suggest a homogeneity of altered cortical structures in adolescents with depressive symptoms.
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Encéfalo , Substância Cinzenta , Adulto , Humanos , Adolescente , Criança , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Lobo Frontal , Emoções , Giro do Cíngulo , Imageamento por Ressonância Magnética/métodosRESUMO
OBJECTIVE: The goal of the current study was to determine the extent to which atypical neural responsiveness during retaliation is associated with observed aggression in youth in residential care. METHOD: This functional magnetic resonance imaging study involved 83 adolescents (56 male and 27 female; mean age, 16.18 years) in residential care performing a retaliation task. Of the 83 adolescents, 42 displayed aggressive behavior within the first 3 months of residential care, whereas 41 did not. During the retaliation task, participants were offered either fair or unfair divisions of $20 pots (allocation phase) and could either accept the offer or reject it, and, by spending $1, $2, or $3, punish the partner (retaliation phase). RESULTS: The study's main findings were that aggressive adolescent showed the following: reduced down-regulation of activity within regions involved in representing the expected value of choice options (left ventromedial prefrontal cortex and left posterior cingulate cortex) as a function of offer unfairness and retaliation level; and reduced recruitment of regions implicated in response control (right inferior frontal gyrus and bilateral anterior insular cortex) and associated fronto-parietal regions as a function of retaliation level. The aggressive adolescents were also significantly more likely to have been aggressive prior to residential care and showed a strong trend for increased retaliation on the task. CONCLUSION: We suggest that individuals with a greater propensity for aggression show reduced representation of the negative consequences of retaliation and associated reduced recruitment of regions potentially involved in over-ruling these negative consequences to engage in retaliation. DIVERSITY & INCLUSION STATEMENT: We worked to ensure sex and gender balance in the recruitment of human participants. We worked to ensure that the study questionnaires were prepared in an inclusive way. We worked to ensure race, ethnic, and/or other types of diversity in the recruitment of human participants. We worked to ensure sex balance in the selection of non-human subjects. We actively worked to promote sex and gender balance in our author group. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work. While citing references scientifically relevant for this work, we also actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our reference list. While citing references scientifically relevant for this work, we also actively worked to promote sex and gender balance in our reference list. We actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our author group.
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Agressão , Córtex Pré-Frontal , Humanos , Masculino , Feminino , Adolescente , Agressão/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Motivação , Lobo Parietal , Imageamento por Ressonância Magnética/métodosRESUMO
Background: Conduct disorder (CD) involves a group of behavioral and emotional problems that usually begins during childhood or adolescence. Structural brain alterations have been observed in CD, including the amygdala, insula, ventrolateral and medial prefrontal cortex, anterior cingulate cortex, and fusiform gyrus. The current study developed a multivariate generalized linear model (GLM) to differentiate adolescents with CD from typically developing (TD) adolescents in terms of grey matter volume (GMV). Methods: The whole-brain structural MRI data were collected from 96 adolescents with CD (mean age = years; mean IQ = ; 63 males) and 90 TD individuals (mean age = years; mean IQ = ; 59 males) matched on age, IQ, and sex. Region-wise GMV was extracted following whole-brain parcellation into 68 cortical and 14 subcortical regions for each participant. A multivariate GLM was developed to predict the GMV of the pre-hypothesized regions-of-interest (ROIs) based on CD diagnosis, with intracranial volume, age, sex, and IQ serving as the covariate. Results: A diagnosis of CD was a significant predictor for GMV in the right pars orbitalis, right insula, right superior temporal gyrus, left fusiform gyrus, and left amygdala (F(1, 180) = 5.460 - 10.317, p < 0.05, partial eta squared = 0.029 - 0.054). The CD participants had smaller GMV in these regions than the TD participants (MCD - MTD = [-614.898] mm3 - [-53.461] mm3). Conclusions: Altered GMV within specific regions may serve as a biomarker for the development of CD in adolescents. Clinical work can potentially target these biomarkers to treat adolescents with CD.
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BACKGROUND: Conduct disorder (CD) involves a group of behavioral and emotional problems that usually begins during childhood or adolescence. Structural brain alterations have been observed in CD, including the amygdala, insula, ventrolateral and medial prefrontal cortex, anterior cingulate cortex, and fusiform gyrus. The current study developed a multivariate generalized linear model (GLM) to differentiate adolescents with CD from typically developing (TD) adolescents in terms of grey matter volume (GMV). METHODS: The whole-brain structural MRI data were collected from 96 adolescents with CD (mean age = [Formula: see text] years; mean IQ = [Formula: see text]; 63 males) and 90 TD individuals (mean age = [Formula: see text] years; mean IQ = [Formula: see text]; 59 males) matched on age, IQ, and sex. Region-wise GMV was extracted following whole-brain parcellation into 68 cortical and 14 subcortical regions for each participant. A multivariate GLM was developed to predict the GMV of the pre-hypothesized regions-of-interest (ROIs) based on CD diagnosis, with intracranial volume, age, sex, and IQ serving as the covariate. RESULTS: A diagnosis of CD was a significant predictor for GMV in the right pars orbitalis, right insula, right superior temporal gyrus, left fusiform gyrus, and left amygdala (F(1, 180) = 5.460-10.317, p < 0.05, partial eta squared = 0.029-0.054). The CD participants had smaller GMV in these regions than the TD participants (MCD-MTD = [- 614.898] mm3-[- 53.461] mm3). CONCLUSIONS: Altered GMV within specific regions may serve as a biomarker for the development of CD in adolescents. Clinical work can potentially target these biomarkers to treat adolescents with CD.
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Suicide is the third leading cause of death for individuals between 15 and 19 years of age. The high suicide mortality rate and limited prior success in identifying neuroimaging biomarkers indicate that it is crucial to improve the accuracy of clinical neural signatures underlying suicide risk. The current study implements machine-learning (ML) algorithms to examine structural brain alterations in adolescents that can discriminate individuals with suicide risk from typically developing (TD) adolescents at the individual level. Structural MRI data were collected from 79 adolescents who demonstrated clinical levels of suicide risk and 79 demographically matched TD adolescents. Region-specific cortical/subcortical volume (CV/SCV) was evaluated following whole-brain parcellation into 1000 cortical and 12 subcortical regions. CV/SCV parameters were used as inputs for feature selection and three ML algorithms (i.e., support vector machine [SVM], K-nearest neighbors, and ensemble) to classify adolescents at suicide risk from TD adolescents. The highest classification accuracy of 74.79% (with sensitivity = 75.90%, specificity = 74.07%, and area under the receiver operating characteristic curve = 87.18%) was obtained for CV/SCV data using the SVM classifier. Identified bilateral regions that contributed to the classification mainly included reduced CV within the frontal and temporal cortices but increased volume within the cuneus/precuneus for adolescents at suicide risk relative to TD adolescents. The current data demonstrate an unbiased region-specific ML framework to effectively assess the structural biomarkers of suicide risk. Future studies with larger sample sizes and the inclusion of clinical controls and independent validation data sets are needed to confirm our findings.
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BACKGROUND: The current study aimed to address two gaps in the literature on child maltreatment, reinforcement processing and psychopathology. First, the extent to which compromised reinforcement processing might be particularly associated with either neglect or abuse. Second, the extent to which maltreatment-related compromised reinforcement processing might be associated with particular symptom sets (depression, conduct problems, anxiety) or symptomatology more generally. METHODS: A sample of adolescents (N = 142) aged between 14 and 18 years with varying levels of prior maltreatment participated in this fMRI study. They were scanned while performing a passive avoidance learning task, where the participant learns to respond to stimuli that engender reward and avoid responding to stimuli that engender punishment. Maltreatment (abuse and neglect) levels were assessed with the Childhood Trauma Questionnaire (CTQ). RESULTS: We found that: (i) level of neglect, but not abuse, was negatively associated with differential BOLD responses to reward-punishment within the striatum and medial frontal cortex; and (ii) differential reward-punishment responses within these neglect-associated regions were particularly negatively associated with level of conduct problems. CONCLUSION: Our findings demonstrate the adverse neurodevelopmental impact of childhood maltreatment, particularly neglect, on reinforcement processing. Moreover, they suggest a neurodevelopmental route by which neglect might increase the risk for conduct problems.
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Maus-Tratos Infantis , Adolescente , Ansiedade , Transtornos de Ansiedade , Criança , Humanos , Imageamento por Ressonância Magnética , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Generalized anxiety disorder (GAD) can significantly impair quality of life and is associated with a relatively poor long-term prognosis. Anxiety disorders are often associated with hyper-responsiveness to threat, perhaps coupled with impaired executive functioning. However, GAD, particularly adolescent GAD, has been the focus of little functional neuroimaging work compared to other anxiety disorders. Here, we examine the neural association of adolescent GAD with responsiveness to threat and response control. METHODS: The study involved 35 adolescents with GAD and 34 healthy comparison individuals (N = 69) matched on age, gender, and IQ. Participants were scanned during an affective number Stroop task. RESULTS: We found significant Group-by-Task Condition interactions in regions involved in response control/motor responding (bilateral precentral gyri and cerebellum) and/or cognitive control/attention (dorsomedial and lateral frontal cortex, posterior cingulate cortex, cuneus, and precuneus). In line with predictions, the youth with GAD showed significantly less recruitment during task trials than the healthy comparison individuals. However, no indications of specific heightened responses to threat were seen. CONCLUSIONS: GAD involves reduced capacity for engaging regions involved in response control/motor responding and/or cognitive control/attention. This might reflect either a secondary consequence of the patient's worry or an early risk factor for the development of worry.
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Imageamento por Ressonância Magnética , Qualidade de Vida , Adolescente , Transtornos de Ansiedade , Atenção , Humanos , Teste de StroopRESUMO
While neuro-cognitive work examining aggression has examined patients with conditions at increased risk for aggression or individuals self-reporting past aggression, little work has attempted to identify neuro-cognitive markers associated with observed/recorded aggression. The goal of the current study was to determine the extent to which aggression by youth in the first three months of residential care was associated with atypical responsiveness to threat stimuli. This functional MRI study involved 98 (68 male; mean age = 15.96 [sd = 1.52]) adolescents in residential care performing a looming threat task involving images of threatening and neutral human faces or animals that appeared to be either loom or recede. Level of aggression was negatively associated with responding to looming stimuli (irrespective of whether these were threatening or neutral) within regions including bilateral inferior frontal gyrus, right inferior parietal lobule, right superior/middle temporal gyrus and a region of right uncus proximal to the amygdala. These data indicate that aggression level is associated with a decrease in responsiveness to a basic threat cue-looming stimuli. Reduced threat responsiveness likely results in the individual being less able to represent the negative consequences that may result from engaging in aggression, thereby increasing the risk for aggressive episodes.
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Agressão , Encéfalo , Adolescente , Tonsila do Cerebelo , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Lobo TemporalRESUMO
Background: Irritability and callous-unemotional (CU; reduced guilt/empathy) traits vary dimensionally in the typically developing population but may be particularly marked in youth with conduct disorder (CD). While these dimensional traits are positively correlated, they have been associated with divergent forms of dysfunction, particularly with respect to threat processing (i.e., irritability with increased, and CU traits with decreased, threat responsiveness). This suggests that interactions between these two dimensions may be complex at the neurobiological level. However, this issue has received minimal empirical attention. Methods: The study included 105 adolescents (typically developing and cases with CD; N = 59). They were scanned with fMRI during a looming threat task that involved images of threatening and neutral human faces or animals that appeared to be either looming or receding. Results: Significant irritability-by-CU traits-by-Direction-by-Emotion interactions were seen within right thalamus/PAG, left lingual gyrus and right fusiform gyrus; irritability was positively associated with the BOLD response for Looming Threatening vs. Receding Threatening trials, particularly for youth with low CU traits. In contrast, CU traits were negatively associated with the same differential BOLD response but particularly for youth showing higher levels of irritability. Similar findings were seen within left ventral anterior and posterior cingulate cortices, though the addition of the interaction with CU traits was only seen at slightly more lenient thresholds. Conclusions: The results support previous work linking irritability to increased, and CU traits to reduced, threat responsiveness. However, for adolescents with high irritability, if CU traits are also high, the underlying neuropathology appears to relate to reduced, rather than increased, threat responsiveness.
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Previous studies examining structural brain correlates of irritability have taken a region-specific approach and have been relatively inconsistent. In a sample of adolescents with and without clinically impairing irritability, the current study examines: (i) cortical volume (CV) in canonical functional networks; (ii) the association between the CV of functional networks and severity of irritability; and (iii) the extent to which IQ mediates the association between structural abnormalities and severity of irritability. Structural MRI and IQ data were collected from 130 adolescents with high irritability (mean age = 15.54±1.83 years, 58 females, self-reported Affective Reactivity Index [ARI] ≥ 4) and 119 adolescents with low irritability (mean age = 15.10±1.93 years, 39 females, self-reported ARI < 4). Subject-specific network-wise CV was estimated after parcellating the whole brain into 17 previously reported functional networks. Our Multivariate Analysis of Covariance (MANCOVA) revealed that adolescents with high irritability had significantly reduced CV of the bilateral control and default-mode networks (p < 0.05) relative to adolescents with low irritability. Multiple regression analyses showed a significant negative association between the control network CV and the severity of irritability. Mediation analysis showed that IQ partially mediated the association between the control network CV and the severity of irritability. Follow-up analysis on subcortical volume (SCV) showed that adolescents with high irritability had reduced bilateral SCV within the amygdala relative to adolescents with low irritability. Reduced CV within bilateral control and default networks and reduced SCV within bilateral amygdala may represent core features of the pathophysiology of irritability. The current data also indicate the potential importance of a patient's IQ in determining how pathophysiology related to the control network is expressed.