Biology subjects

Okon-Singer, H.

Publications and source records attributed to Okon-Singer, H..

3 recordsLinked to original sources

bioRxiv2023

Attentional Engagement and Disengagement: Quantifying Attentional Shifts Utilizing the Steady State Visual Evoked Potentials

A large body of ssVEP research has provided significant insights into the temporal dynamics of attentional processes. While these studies focused primarily on group level inspection, there is a need for further research employing methodological approaches that enable the examination of individual-level variability. This is particularly relevant in psychological contexts, where such measures are linked to various cognitive and clinical outcomes. In the present study, we aimed to measure and discern attentional shift processes, examining both group and individual subject dynamics. We utilized EEG frequency tagging to examine attentional engagement, disengagement, and reengagement while participants switched focus between four flickering stimuli. Analysis of ssVEPs revealed significant changes in amplitude between attentional conditions. Specifically, group-level results indicated an increase in activity during engagement with the first target, followed by a decrease upon disengagement, while reengagement with the second target showed a corresponding increase in activity occurring on average 110 ms prior to disengagement. Distinct individual patterns emerged, with participants showing either disengagement, reengagement, both, or no shifts. Notably, the timing and order of these attentional shifts varied considerably across individuals relative to target switch events. These findings demonstrate the ability of this approach to quantify attentional shifts on both group and individual levels, providing a foundation for further research into individual differences in attentional control, which may have implications for understanding adaptive and maladaptive psychological functioning. HighlightsO_LIEEG frequency tagging captures attentional engagement, disengagement, and reengagement processes. C_LIO_LIGroup-level ssVEP analysis reveals that attentional reengagement occurs 110 ms before attentional disengagement. C_LIO_LIIndividual-level analysis demonstrates diverse patterns of attentional shift timing and order. C_LIO_LIThe experimental framework successfully quantifies attentional dynamics on the group and individual levels. C_LI

neuroscience↗

bioRxiv2018

Girls’ attentive traits associate with cerebellar to dorsal attention and default mode network connectivity

Attention traits are a cornerstone to the healthy development of childrens performance in the classroom, their interactions with peers, and in predicting future success and problems. The cerebellum is increasingly appreciated as a region involved in complex cognition and behavior, and moreover makes important connections to key brain networks known to support attention: the dorsal attention and default mode networks (DAN; DMN). The cerebellum has also been implicated in childhood disorders affecting attention, namely autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD), suggesting that attention networks extending to the cerebellum may be important to consider in relation to attentive traits. Yet, direct investigations into the association between cerebellar FC and attentive traits are lacking. Therefore, in this study we examined attentive traits, assessed using parent reports of ADHD and ASD symptoms, in a community sample of 52 girls aged 4-7 years, i.e. around the time of school entry, and their association with cerebellar connections with the DAN and DMN. We found that cortico-cerebellar functional connectivity (FC) jointly and differentially correlated with attentive traits, through a combination of weaker and stronger FC across anterior and posterior DAN and DMN nodes. These findings suggest that cortico-cerebellar integration may play an important role in the manifestation of attentive traits.

neuroscience↗

bioRxiv2017

Association of Peripheral Blood Pressure with Grey Matter Volume in 19- to 40-Year-Old Adults

ObjectiveTo test whether elevated blood pressure (BP) relates to grey matter volume (GMV) changes in young adults who had not previously been diagnosed as hypertensive (systolic BP (SBP)/diastolic BP (DBP)[≥]140/90 mmHg).\n\nMethodsWe associated BP with GMV from structural 3 Tesla T1-weighted MRI of 423 healthy adults between 19-40 years (mean age=27.7{+/-}5.3 years, 177 women, SBP/DBP=123.2/73.4{+/-}12.2/8.5 mmHg). Data originated from four previously unpublished cross-sectional studies conducted in Leipzig, Germany. We performed voxel-based morphometry on each study separately and combined results in image-based meta-analyses (IBMA) to assess cumulative effects across studies. Resting BP was assigned to one of four categories: (1) SBP<120 and DBP<80 mmHg, (2) SBP 120-129 or DBP 80-84 mmHg, (3) SBP 130-139 or DBP 85-89 mmHg, (4) SBP[≥]140 or DBP[≥]90 mmHg.\n\nResultsIBMA yielded: (a) lower regional GMV was correlated with higher peripheral BP; (b) lower GMV with higher BP when comparing individuals in sub-hypertensive categories 3 and 2, respectively, to those in category 1; (c) lower BP-related GMV was found in regions including hippocampus, amygdala, thalamus, frontal and parietal structures (e.g. precuneus).\n\nConclusionsBP[≥]120/80 mmHg was associated with lower GMV in regions that have previously been related to GM decline in older individuals with manifest hypertension. Our study shows that BP-associated GM alterations emerge continuously across the range of BP and earlier in adulthood than previously assumed. This suggests that treating hypertension or maintaining lower BP in early adulthood might be essential for preventing the pathophysiological cascade of asymptomatic cerebrovascular disease to symptomatic end-organ damage, such as stroke or dementia.

neuroscience↗