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Berchio, C.

Publications and source records attributed to Berchio, C..

3 recordsLinked to original sources

Temporal dynamics of cognitive flexibility in adolescents with anorexia nervosa: a high density EEG study

Cognitive rigidity is a core symptom of anorexia nervosa (AN) and is associated with treatment resistance. Nevertheless, studies on the neural basis of cognitive flexibility (CF) in adolescent AN are rare. The aim of this study was to investigate temporal brain dynamics of CF in adolescents with AN and their tendency to experience anxiety. To address this aim, participants performed a Dimensional Change Card Sorting task during high-density EEG recording. Transient state and stable traits of anxiety were measured with the State-Trait Anxiety Inventory. Data were collected on 22 girls with AN, and 23 healthy controls (HC) (aged 12-20 years old). Evoked potentials were investigated using microstates analysis. Effects of trait and state anxiety on microstates parameters were investigated performing correlations across groups and in the AN group only. Adolescents with AN did not differ from HC with respect to behavioral switching cost, despite a greater overall accuracy. Adolescents with AN showed altered visual orienting processes (N100 micro-state), and earlier attentional processing to task switching (P300b microstate) when compared to HC. Reduced activation in a network involving the pre-central cortex, the cerebellum, and the posterior cingulate was identified in adolescents with AN. Trait and state anxiety were correlated with atypical AN microstates across groups. The present findings suggest CF manifests with inefficient behavioral and neural strategies in adolescents with AN, at early stages in the illness. Additionally, this study provides evidence that transient and stable tendencies to experience anxiety could represent a vulnerability to developing CF impairments in adolescent AN.

neuroscience↗

Dysfunctional temporal stages of eye-gaze perception in adults with ADHD: a high-density EEG study

ADHD have been associated with social cognitive impairments across the lifespan, but no studies have specifically addressed the presence of abnormalities in eye-gaze processing in the adult brain. This study investigated the neural basis of eye-gaze perception in adults with ADHD using event-related potentials (ERP). Twenty-three ADHD and 23 controls performed a delayed face-matching task with neutral faces that had either direct or averted gaze. ERPs were classified using microstate analyses. ADHD and controls displayed similar P100 and N170 microstates. ADHD was associated with cluster abnormalities in the attention-sensitive P200 to direct gaze, and in the N250 related to facial recognition. For direct gaze, source localization revealed reduced activity in ADHD for the P200 in the left/midline cerebellum, as well as in a cingulate-occipital network at the N250. These results suggest brain impairments involving eye-gaze decoding in adults with ADHD, suggesting that neural deficits persist across the lifespan.

neuroscience↗

Deviant EEG resting-state large-scale brain network dynamics in euthymic bipolar disorder patients

BackgroundNeuroimaging studies provided evidence for disrupted resting-state functional brain network activity in bipolar disorder (BD). Electroencephalographic (EEG) studies found altered temporal characteristics of functional EEG microstates during depressive episode within different affective disorders. Here we investigated whether euthymic patients with BD show deviant resting-state large-scale brain network dynamics as reflected by altered temporal characteristics of EEG microstates.\n\nMethodsWe used high-density EEG to explore between-group differences in duration, coverage and occurrence of the resting-state functional EEG microstates in 17 euthymic adults with BD in on-medication state and 17 age- and gender-matched healthy controls. Two types of anxiety, state and trait, were assessed separately with scores ranging from 20 to 80.\n\nResultsMicrostate analysis revealed five microstates (A-E) in global clustering across all subjects. In patients compared to controls, we found increased occurrence and coverage of microstate A that did not significantly correlate with anxiety scores.\n\nConclusionOur results provide neurophysiological evidence for altered large-scale brain network dynamics in BD patients and suggest the increased presence of A microstate to be an electrophysiological trait characteristic of BD.

neuroscience↗