research

Youth with and without epilepsy differ in 'social brain' connectivity during a social cognitive task, but not at rest

Deficits in social cognition are common in people with epilepsy. This means that individuals with epilepsy may struggle to understand others' intentions in social situations, may find it harder to interpret others' facial expressions or tone of voice in social interactions, or may have trouble forming social connections with others. We know that epilepsy is associated with atypical functioning in regions of the brain that are thought to be involved in social cognition, but most existing research has examined patterns of brain connectivity at rest--that is, when nothing is happening. The current study wanted to investigate whether youth with epilepsy showed different brain connectivity patterns in these 'social brain' areas, when participants were completing a social cognition task. To answer this question, we compared brain connectivity within the "mentalizing network" (involved in theory of mind and other social cognitive functions) and within a network centered around the amygdala (involved in processing salient social information) in youth with and without epilepsy, while they were either completing a facial emotion recognition task or were at rest.

Compared to typically-developing youth, youth with epilepsy showed weaker connectivity between the left posterior superior temporal sulcus and the medial prefrontal cortex of the brain when seeing facial expressions in the emotion recognition task. These regions are thought to work together during social cognitive tasks, so decreased connectivity between these areas may indicate that these network nodes aren't communicating as efficiently or as well as they could be in youth with epilepsy. On the flip side, we found that youth with epilepsy had greater connectivity within the temporal lobe (between the left temporo-parietal junction and the anterior temporal cortex, to be precise) compared to typically-developing adolescents. This pattern was associated with poorer accuracy on the facial emotion recognition task. It is possible that youth with epilepsy are using a different 'strategy' in the task that results in different brain connectivity patterns in the temporal lobe, but we would need to test this possibility explicitly in future studies. In contrast to these findings, youth with and without epilepsy did not differ in their connectivity within either social brain network during resting-state scans (i.e., when they weren't doing a task).

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Overall, our findings highlight that there may be important differences in how regions associated with social cognition are connected to one another during social cognitive tasks in youth with and without epilepsy. Although this is only a first step in understanding this phenomenon, our results indicate that looking at neural connectivity patterns during relevant tasks may be important to understanding the association between epilepsy and social cognitive deficits.

Find out more and read the paper here: https://www.sciencedirect.com/science/article/abs/pii/S0028393221001330

Brain characteristics associated with symptoms of anxiety/depression in youth with epilepsy

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Compared to the general population or to other groups of people with chronic health conditions, individuals with epilepsy are more likely to also experience internalizing disorders (i.e., depression and/or anxiety) during their lifetime. In adults, these comorbid conditions are thought to be indexed by specific neural biomarkers, including irregularities in the structure and function of frontal and temporal regions of the brain. However, less work has investigated whether similar patterns may be noted in children and adolescents with epilepsy, who are at risk of developing depression and/or anxiety. The current study capitalized on the fact that youth with epilepsy often undergo MRI (magnetic resonance imaging) scans, PET (positron emission tomography) scans, and psychological assessments as part of their clinical evaluations. We examined whether youth with epilepsy who experienced clinically-significant levels of internalizing problems had different patterns of brain structure and/or function than youth who scored in the normal range for such symptoms. We found that 42% of youth in our sample scored in the clinical range for internalizing symptoms on a parent-report of psychological well-being (Child Behavior Checklist; Achenbach, 2001)—suggesting that anxiety and depression may be a common concern for many young patients. Symptoms were not predicted by characteristics of the illness (like age of seizure onset or location of seizure focus) nor of the patient (like age or gender). However, youth in the clinical range showed reduced cortical volume overall, as well as cortical thinning and decreased function (measured via glucose reuptake) in bilateral parietal/occipital lobes and left temporal regions, compared to youth in the normal range. A follow-up classifier analysis demonstrated that these brain characteristics were predictive of internalizing problems at an individual level. Taken together, our findings suggest that children and adolescents with epilepsy who show widespread reductions in cortical thickness and neural function in clinical evaluations may benefit from intensified psychological evaluation and support for possible mood and anxiety symptoms.

Read more at: https://www.ncbi.nlm.nih.gov/pubmed/31882324