The effect of anti-saccade training on cognitive function in healthy adults and Parkinson's disease patients
Our novel study investigated how the anti-saccade training can influence cognitive capabilities of healthy and Parkinson’s disease participants. The rationale is that the anti-saccade task requires top-down control and involves cortical cognition areas in the frontal and prefrontal cortices. We hypothesized that anti-saccade training may induce plastic changes in these brain areas resulting in improved top-down control, which would transfer to other unpracticed executive tasks. We conducted two experiments using a pretest-training-posttest design. In our first experiment, we tested the impact of 10 days of interleaved pro/-anti saccade training on cognitive functions in participants with Parkinson’s disease compared to healthy older controls. We tested 9 Parkinson’s and 11 healthy older participants in a spatial working memory task, decision making task, and visual search task before and after training. We compared performance after training to before training. Both Parkinson's and healthy older participants showed some improvements after training; however, these were limited to the visual search task in Parkinson's participants and visual memory and decision making tasks in older heathy participants. In the second experiment, we tested the validity of anti-saccade training; we trained a group of younger participants on the interleaved pro/anti-saccade task and a second group on a pro-saccade only task and compared performance on several cognitive tasks after training to before training. Overall, we observed an improvement after both types of training, with the exception of two tasks, the interleaved pro/-anti saccade task and an oculomotor capture tasks. These two tasks showed benefits only with the interleaved training. A significant interaction between group and testing time was observed for the interleaved task in which participants who performed the pro-only training made significantly more anti-saccade errors in the post-test. This could mean that the pro-only training had a maladaptive effect on anti-saccades. Taken together, the two studies suggest that anti-saccade training has promise to improve some cognitive functions in participants with Parkinson’s disease as well as older controls, however there is insufficient evidence to attribute the improvement to anti-saccade training specifically. Further research is required to address the current study limitations before a final conclusion can be reached.