Presentation Information
[P1-07]Disentangling spatiotemporal correlates of time cognition: an ongoing investigation of the effects of cognitive aging and depressive symptoms
*Giulia Buzi1, Florentine Fricker1, Laura Masson1, Francis Eustache1, Thomas Hinault1 (1. (1)Normandy Univ, UNICAEN, PSL Université Paris, EPHE, Inserm, U1077, CHU de Caen, Centre Cyceron, Neuropsychologie et Imagerie de la Mémoire Humaine, 14000 Caen, France. (France))
Keywords:
Time cognition,Temporal processing,Cognitive aging,Subclinical depression,EEG-fMRI
Processing temporal information is a fundamental feature of our brain and cognitive functions. Timing capacities are known to become less precise and more variable with advancing age, yet not homogenously across individuals. One of the factors explaining this inter-individual variability could be the presence of depressive symptoms, which could hasten cognitive decline but also impact prospective timing of short durations. To investigate the interweaving between cognitive aging, brain temporal processing and depressive symptoms, we are enrolling 50 younger and 80 older adults to assess their cognitive abilities and quantify their depressive symptoms. While undergoing simultaneous EEG-fMRI recording, participants perform a temporal generalization task (e.g., 600, 900, 1250, 1750, 2400 ms) to a reference duration (1500ms). The Full Width at the Half Maximum (FWHM) of the generalization gradient of the OA group (n= 5, Mage = 67.2) was found to be larger (FWHMOA = 2160.36 ms) compared to its younger counterpart (n=5, Mage= 23.8, FWHMYA = 1252.38 ms), suggesting a reduced temporal precision in older adults. Time/Frequency source maps of the difference between the two groups, showed lower Theta (5-7 Hz) magnitude in cingulate (t=-7.105, p<0.001) and Insular cortices (t = -4.970, p<0.001), together with higher gamma (30-59 Hz) rhythms in parietal (t= 6,0086, p<.005), frontal (t=5.019, p<0.05), and cingulate gyrus (t=4.547, p<0.005) in older adults. Although this oscillatory imbalance in frontal-parietal network hubs has previously been linked to disruptions of top-down attention and working memory in aging, we hypothesize that it could reflect an inefficient compensatory mechanism in sub and supra-seconds timing tasks. Further investigation on links between cognitive performance, depressive symptom’s intensity and dissimilarity matrices of the theta-gamma Phase Amplitude Coupling and fMRI connectivity maps, as well as dynamic network modes (DyNeMo) of the fronto-parietal network time series, would help disentangle the spatiotemporal dynamics temporal processing changes with aging.