Event-related potentials accompanying performance of computer mouse pointing task in the long-term dry immersion model of microgravity

Abstract

Ten healthy volunteers participated in the ground imitation of a microgravity condition. For three weeks they stayed in the water filled tub without bodily support in supine position while isolated by waterproof material (this procedure is known as dry immersion - DI). During this period, they performed computer mouse pointing task and corresponding brain activity was evaluated by means of EEG: movement related and cognitive event-related potentials as well as resting state electroencephalogram were registered). Pointing task was performed before DI and at the time after initial period of adaptation – at the 5th and 17th days of DI. No deterioration of pointing task performance was found. Movement related potentials were not changed as well as cognitive peak P3, and only N1 peak significantly decreased at the 17th day of DI. Occipital alpha EEG also became significantly more pronounced at the 17th day of DI. Dry immersion procedure is thought to reproduce space flight physiological effects quite well, due to the DI specific feature – support withdrawal. Thus, results obtained indicate that support withdrawal also affects brain functioning in a specific way: increased alpha EEG is accompanied by altered visual processing (as indexed by diminished N1). Although these alterations are not sufficient to disrupt well learned mouse pointing task.