Biology subjects

Marinkovic, K.

Publications and source records attributed to Marinkovic, K..

4 recordsLinked to original sources

bioRxiv2021

Increased heterogeneity and task-related reconfiguration of functional connectivity within a lexicosemantic network in autism

Autism spectrum disorder (ASD) is highly heterogeneous in etiology and clinical presentation. Findings on intrinsic functional connectivity (FC) or task-induced FC in ASD have been inconsistent including both over- and underconnectivity and diverse regional patterns. As FC patterns change across different cognitive demands, a novel and more comprehensive approach to network architecture in ASD is to examine the change in FC patterns between rest and task states, referred to as reconfiguration. This approach is suitable for investigating inefficient network connectivity that may underlie impaired behavioral functioning in clinical disorders. We used functional magnetic resonance imaging (fMRI) to examine FC reconfiguration during lexical processing, which is often affected in ASD, with additional focus on interindividual variability. Thirty adolescents with ASD and a matched group of 23 typically developing (TD) participants completed a lexicosemantic decision task during fMRI, using multiecho-multiband pulse sequences with advanced BOLD signal sensitivity and artifact removal. Regions of interest (ROIs) were selected based on task-related activation across both groups, and FC and reconfiguration were compared between groups. The ASD group showed increased interindividual variability and overall greater reconfiguration than the TD group. An ASD subgroup with typical performance accuracy (at the level of TD participants) showed reduced similarity and typicality of FC during the task. In this ASD subgroup, greater FC reconfiguration was associated with increased language skills. Findings suggest that intrinsic functional networks in ASD may be inefficiently organized for lexicosemantic decisions and may require greater reconfiguration during task processing, with high performance levels in some individuals being achieved through idiosyncratic mechanisms. HighlightsFC reconfiguration is a comprehensive approach to examining network architecture Functional networks are inefficiently organized for lexicosemantic decisions in ASD ASD may require greater reconfiguration during task processing Some ASD individuals achieve high performance through idiosyncratic mechanisms

neuroscience↗

bioRxiv2021

Alcohol cues elicit different abnormalities in brain networks of abstinent men and women with alcohol use disorders

We employed fMRI in 84 men and women with and without a history of alcohol use disorders (ALC and NC, respectively), to explore how gender interacts with alcoholism as reflected in brain activity elicited by alcohol cues. Brain activation was measured in a working memory task (delayed matching-to-sample) with emotional faces as the sample and match cues. During the delay period, intervening distractors were either reward-salient cues (alcoholic beverages) or neutral cues (nonalcoholic beverages or scrambled pictures). ALC women (ALCw) had higher accuracy than ALC men (ALCm). Analyses of scans during the viewing of distractor images revealed significant group-by-gender interactions. Compared to NC men, ALCm evidenced lower activation contrast between reward-salient cues and neutral cues in default mode network regions (including superior prefrontal and precuneus areas), while ALCw had more activation than NC women. Similar interactions were observed for task-regions (including superior parietal, lateral occipital, and prefrontal areas). Region of interest analyses showed that the ALC group had significantly higher levels of activation throughout reward-related circuitry during alcohol distractor interference than during scrambled picture interference. These results suggest that abstinent ALCm and ALCw differ in processing reward-salient cues, which can impact treatment and recovery. HighlightsBrain reward regions activate highly when individuals with a history of alcohol use disorders view alcoholic beverages. The brain regions identified subserve vision, memory, and judgement. Opposite abnormalities in activation patterns appeared for alcoholic men and women.

neuroscience↗

bioRxiv2019

Brain Responsivity to Emotional Faces Differs in Alcoholic Men and Women

Inclusion of women in alcoholism research has shown that gender differences contribute to unique profiles of cognitive, emotional, and neuropsychological dysfunction. We employed functional magnetic resonance imaging (fMRI) of abstinent long-term alcoholics (21 women [ALCw] and 21 men [ALCm]) and demographically-similar nonalcoholic controls (21 women [NCw] and 21 men [NCm]) to explore how gender and alcoholism interact to influence emotional processing and memory. Participants completed a delayed match-to-sample emotional face memory fMRI task. While the results corroborated reports implicating amygdalar, superior temporal, and cerebellar involvement in emotional processing overall, the alcoholic participants showed hypoactivation of the left intraparietal sulcus to encoding the identity of the emotional face stimuli. The nonalcoholic participants demonstrated more reliable gender differences in neural responses to encoding the identity of the emotional faces than did the alcoholic group, and widespread neural responses to these stimuli were more pronounced in the NCw than in the NCm. By comparison, gender differences among ALC participants were either smaller or in the opposite direction (higher brain activation in ALCm than ALCw). Specifically, Group by Gender interaction effects indicated stronger responses to emotional faces by ALCm than ALCw in the left superior frontal gyrus and the right inferior frontal sulcus, while NCw had stronger responses than NCm. However, this pattern was inconsistent throughout the brain, with results suggesting the reverse direction of gender effects in the hippocampus and anterior cingulate cortex. Together, these findings demonstrated that gender plays a significant role in the profile of functional brain abnormalities observed in alcoholism.

neuroscience↗

bioRxiv2018

Alcoholism Gender Differences in Brain Responsivity to Emotional Stimuli

Men and women may use alcohol to regulate their emotions differently, with corresponding differences in neural responses. We examined how photographs of emotional stimuli impacted brain activity obtained through functional magnetic resonance imaging (fMRI) from 42 alcoholic (25 women) and 46 nonalcoholic (24 women) participants. Brain responsivity was blunted in alcoholic compared to nonalcoholic groups. Further analyses indicated significant gender differences in the impact of alcoholism. Brain activation of the alcoholic men (ALCM) was significantly lower than that of the alcoholic women (ALCW) and nonalcoholic men (NCM) in regions including the inferior parietal gyrus, anterior cingulate gyrus, and postcentral gyrus, whereas activation was higher in the ALCW than in the nonalcoholic women (NCW) in superior frontal and supramarginal cortical regions. The reduced brain reactivity of ALCM and increases for ALCW highlighted divergent brain regions and gender effects, suggesting possible differences in the underlying basis for development of alcohol use disorders.

neuroscience↗