2.Lomonosov Moscow State University, Moscow, Russia
Saccadic eye movement and cognitive processes are closely linked. For Parkinson's disease is characterized by a parallel deterioration in motor and cognitive functions. Accordingly, in the present study we investigated the changes in saccadic eye movements recorded over a standard technique in various States from quiet wakefulness with eyes open to perform cognitive tasks of increasing difficulty using a computer version of the psychological techniques of "Prognozis-2" (Riabchikova et al., Bul. exp. biol. med., no. 1, 2009), in patients with Parkinson's
disease before treatment as compared with healthy relationship. Assessed attention, memory and the process of anticipating events. Compared the average number of saccadic in 1 sec. Healthy subjects demonstrated good performance on all test functions. They showed significant increase in number saccades per 1 sec during the prediction compared to the of calm wakefulness with open eyes. In addition, the increased number of saccades per unit time was related with complexity of the tasks. The patients were good indicators of attention and memory and poor predictive performance. Patients required significantly more time to complete assignments. A number of forecast error was several times higher than 12 (indicator, which shows the low predictive activity). The patients have no mistakes of distraction. Number of saccadic per unit time in the background of this group did not differ from that of healthy subjects. When performing cognitive tasks this figure increased, but to a lesser degree than in the healthy group, and has not increased but decreased by complexity of the tasks.
It is known that cognitive processes demanding attention are suppressed by saccades. Therefore good indicators of attention in patients can be attributed to the suppression of saccadic, growing when jobs become more complex. Increase in the time required to perform cognitive tasks is related not only to their complexity, but also to the need to commit large numbers of saccades in addressing them. Hence, a reduction in the number of saccades per time unit requires an increase in the length of time to complete each of the tasks.