Investigating patterns of neural response associated with childhood abuse v. childhood neglect.

BACKGROUND: Childhood maltreatment is robustly associated with increased risk of poor mental health outcome and changes in brain function. The authors investigated whether childhood experience of abuse (e.g. physical, emotional and sexual abuse) and neglect (physical and emotional deprivation) was differentially associated with neural reactivity to threat. METHODS: Participants were drawn from an existing study and allocated to one of four groups based on self-report of childhood maltreatment experience: individuals with childhood abuse experiences (n = 70); individuals with childhood neglect experiences (n = 87); individuals with combined experience of childhood abuse and neglect (n = 50); and non-maltreated individuals (n = 207) propensity score matched (PSM) on gender, age, IQ, psychopathology and SES. Neural reactivity to facial cues signalling threat was compared across groups, allowing the differential effects associated with particular forms of maltreatment experience to be isolated. RESULTS: Brain imaging analyses indicated that while childhood abuse was associated with heightened localised threat reactivity in ventral amygdala, experiences of neglect were associated with heightened reactivity in a distributed cortical fronto-parietal network supporting complex social and cognitive processing as well as in the dorsal amygdala. Unexpectedly, combined experiences of abuse and neglect were associated with hypo-activation in several higher-order cortical regions as well as the amygdala. CONCLUSIONS: Different forms of childhood maltreatment exert differential effects in neural threat reactivity: while the effects of abuse are more focal, the effects of neglect and combined experiences of abuse are more distributed. These findings are relevant for understanding the range of psychiatric outcomes following childhood maltreatment and have implications for intervention.

Impulsivity and the modular organization of resting-state neural networks.

Impulsivity is a complex trait associated with a range of maladaptive behaviors, including many forms of psychopathology. Previous research has implicated multiple neural circuits and neurotransmitter systems in impulsive behavior, but the relationship between impulsivity and organization of whole-brain networks has not yet been explored. Using graph theory analyses, we characterized the relationship between impulsivity and the functional segregation ("modularity") of the whole-brain network architecture derived from resting-state functional magnetic resonance imaging (fMRI) data. These analyses revealed remarkable differences in network organization across the impulsivity spectrum. Specifically, in highly impulsive individuals, regulatory structures including medial and lateral regions of the prefrontal cortex were isolated from subcortical structures associated with appetitive drive, whereas these brain areas clustered together within the same module in less impulsive individuals. Further exploration of the modular organization of whole-brain networks revealed novel shifts in the functional connectivity between visual, sensorimotor, cortical, and subcortical structures across the impulsivity spectrum. The current findings highlight the utility of graph theory analyses of resting-state fMRI data in furthering our understanding of the neurobiological architecture of complex behaviors.

Evaluation and characterization of generalized anxiety and depression in patients with primary brain tumors.

To determine clinical and sociodemographic factors that are associated with major neuropsychiatric illnesses among brain tumor patients, we administered a modified version of the Brief Patient Health Questionnaire and a demographic data form to 363 adult neuro-oncology patients. Responses were analyzed to assess for associations between demographic variables, clinical variables, and symptoms consistent with diagnoses of generalized anxiety disorder and/or depression. Multivariate logistic regression analyses showed that female gender was associated with the presence of symptoms of anxiety, depression, and combined anxiety and depression. Lower WHO tumor grade classifications, lower education level, and a history of psychiatric illness also emerged as important predictors of symptoms consistent with anxiety and/or depression. Marital status and presence of past/current medical illness trended toward being significantly associated with depression alone. Patient use of psychiatric medication was not associated with any study variables. Results of the present study suggest several hypotheses to test with neuro-oncology patients in further longitudinal analyses, which would benefit from the inclusion of a wider range of neuropsychiatric symptoms in conjunction with neurocognitive and functional impairment variables.