Compensatory Brain Activity in Older Adults. The Search for the Electrophysiological Indicators of Cognitive Processes Involved in This Activity, and Its Possible Changes Induced by Working Memory Training

There are two important aspects in which the present project will allow to enrich our understanding of compensatory brain activity in older adults. First, in the studies that have been conducted so far the compensatory brain activity in older adults was investigated primarily with the use of the functional magnetic resonance (fMRI) or positon emission tomography (PET). In order to identify compensatory activity in our study we will use electroencephalographic markers (observable in EEG). It will allow to confirm the assumptions about compensatory brain activity relying on new data, as in EEG research the brain markers of the same cognitive processes are different from those used in fMRI and PET research. What is more, in the studies conducted so far brain activity in older adults was only registered and interpreted, whereas the present study additionally adds the training component. The aim of our study is to see if it is possible to influence the compensatory brain activity through cognitive functions training, relying on working memory training. Theoretically, such a training should optimize brain activity in older adults, namely evoke compensatory brain activity during difficult tasks in order to make them easier, whereas in the case of easy tasks it should lead to the disappearance of the need to trigger compensatory activity. This assumption will be verified in an experimental setting. The participants will be divided into six groups: two experimental (the groups of young and old adults), and by analogy two active control groups and two passive (no-contact) control groups. The experiment was designed in the following way: (1) All groups will be subjected to pre-test measurements that will be EEG registration during a cognitive task execution at different difficulty levels; (2) Experimental groups will undergo working memory training. Over the period of 4 weeks participants in the experimental groups will take part in 12 training sessions. In the active control groups instead of the n-back training the practice of tasks which do not involve working memory will be introduced. Participants of the passive control groups will be awaiting post-test (no-contact control); (3) In all groups post-test measurements will be administered analogically to the pre-test measurements in order to assess changes in cognitive tasks performance and related brain activity.