Cerebral functional networks during sleep in young and older individuals

ABSTRACT: Even though sleep modification is a hallmark of the aging process, age-related changes in functional connectivity using functional Magnetic Resonance Imaging (fMRI) during sleep, remain unknown. Here, we combined electroencephalography and fMRI to examine functional connectivity differences between wakefulness and light sleep stages (N1 and N2 stages) in 16 young (23.1 ± 3.3y; 7 women), and 14 older individuals (59.6 ± 5.7y; 8 women). Results revealed extended, distributed (inter-between) and local (intra-within) decreases in network connectivity during sleep both in young and older individuals. However, compared to the young participants, older individuals showed lower decreases in connectivity or even increases in connectivity between thalamus/basal ganglia and several cerebral regions as well as between frontal regions of various networks. These findings reflect a reduced ability of the older brain to disconnect during sleep that may impede optimal disengagement for loss of responsiveness, enhanced lighter and fragmented sleep, and contribute to age effects on sleep-dependent brain plasticity

Bridging the gap between perception and action: the case for neuroimaging, AI and video games

A fundamental goal of computational neuroscience is to account for the implementation of cognitive processes in the brain, yet current models tend to focus on elementary cognitive processes. By contrast, video games have been designed to fully engage players, and require to constantly monitor the state of the game, in parallel to integrating strategic planning, decision making and taking action. While playing video games is hard, recent advances in artificial intelligence (AI) have made it possible to train deep neural networks that reach or even surpass human performance. We discuss challenges and opportunities in training artificial neural networks that could account jointly for human brain activity and behaviour during video game play. We argue that large-scale neuroimaging data may help to constrain the training of artificial networks and open new avenues for research at the intersection of neuroscience and AI

IRM et santé auditive: Suivi longitudinal de l’audition chez des participants de recherche scannés plus de 100 fois sur une période de trois ans

Poster presentation prepared for Université de Montréal's 15th Psychology department scientific day (May 18th, 2022

MRI noise and auditory health: Can one hundred scans be linked to hearing loss? The case of the Courtois NeuroMod project

Magnetic resonance imaging (MRI) is one of the most commonly used tools in neuroscience. However, it implies exposure to high noise levels. Exposure to noise can lead to temporary or permanent hearing loss, especially when the exposure is long and/or repeated. Little is known about the hearing risks for people undergoing several MRI examinations, especially in the context of longitudinal studies. The goal of this study was to assess the potential impact of repeated exposure to MRI noise on hearing in research participants undergoing dozens of MRI scans. As part of the Courtois NeuroMod project, six participants were scanned up to twice a week with the use of hearing protection. Their hearing was tested periodically, over a period of 1.5 years. First, baseline pure-tone thresholds and distortion product otoacoustic emission (DPOAE) amplitudes were acquired before the beginning of this study. Hearing tests were then scheduled immediately before/immediately after a scan and with a delay of two to seven days after a scan. Pure-tone thresholds and DPOAE amplitudes showed no scanner noise impact right after the scan session when compared to the values acquired right before the scan session. Pure-tone thresholds and DPOAE amplitudes acquired in the delayed condition and compared to the baseline showed similar results. These results suggest an absence of impact from MRI noise exposure. Overall, our results show that intensive longitudinal MRI studies likely do not cause hearing damage to participants when they properly utilize adequate hearing protection

Can the Courtois NeuroMod project be linked to hearing damage?

Poster presentation prepared for the Organization for Human Brain Mapping (OHBM) annual conference (July 22nd - 26th, 2023