Poster C88, Sunday, March 26, 5:00 – 7:00 pm, Pacific Concourse
Age effects on resting state functional connectivity preceding and following an associative learning task.
gwenaelle catheline1,2, manon Edde1, georges Di-scala1, bixente Dilharreguy1, sandra Chanraud1,2; 1INCIA, UMR CNRS 5287, Université de Bordeaux, Bordeaux, France, 2EPHE, PSL Research University.
Associative learning task is more difficult for aging subjects than for young subjects. We hypothesized that the difficulties encountered by aging subjects during the achievement of the task could leave a mark on resting state functional connectivity. In this purpose, we compared rest fMRI before and after an associative learning task in 17 healthy young subjects (24.7 + 2.7 years) and in 14 elderly subjects (65.5+ 2.6 years). Before the task, aging subjects present underconnectivity in various brain regions including occipito-cerebellum network, temporo-frontal network and striato-temporal network. After the task, the pre-task differences were maintained and two other networks present an underconnection in aging subjects compared to young subjects: parahippocampal-cerebellum 4-5 and an hippocampo-frontal networks. We have then tested the association between the level of performance of aging subjects and the level of connectivity of these two networks. A significant correlation was observed between the level of performance and the level of connectivity between the left parahippocampal cortex and the right 4-5 cerebellum measured following the task (rho = 0,536, p < 0,05). In contrast no association was observed with the level of connectivity of the hippocampo-frontal network. Basal resting state connectivity is different between young and older subjects, and this difference is maintained post-task. Moreover, we highlight the involvement of a parahippocampal-cerebellum network for the successful achievement of this associative learning task for the elderly.
Topic Area: LONG-TERM MEMORY: Development & aging