Digital assessments of motor-cognitive performance in young and older adults : behavioral and neural correlates

Abstract

Today's technological advances enable us to have a healthy life. Maintaining mental and physical health is one of the most critical aspects of our healthy life with increasing age. Moreover, one of the many ways to stay healthy is to detect problems of motor or cognitive impairment early and accurately in terms of assessment. Digital assessment can help uncover subtle differences in specific motor and cognitive declines. This early detection can lead to an adequate intervention on time, allowing for preliminary prevention before symptoms occur. From a different perspective, exercise effect on our bodies and minds is indescribable. Physical exercise induces cellular and molecular changes in our body, which positively change the structure and function of the brain. These positive changes in our brains can result in improved cognitive function. These effects are attributed to physical activity over a long-term period. However, understanding the acute effects of exercise-induced changes is also essential to potentially explain chronic effects. Also, identifying exercise-induced cortical activation patterns should be considered for cognitive function enhancements. For this reason, it is necessary to investigate the effect of exercise protocol composition, such as exercise intensity and duration, on cognitive function based on neural correlates. Based on these aspects, the present thesis is divided into two parts. In the first part (Part I: Assessment), the paper-pencil version of Trail-Making-Test (ppTMT), a neuropsychological assessment commonly used to investigate cognitive functions, was compared with the digital Trail-Making-Test (dTMT) developed on a tablet version. We verified its reliability and validity by comparing these two versions of TMT. Also, the dTMT was applied in patients with Parkinson's disease to detect subtle differences in fine motor and cognitive performance deterioration. As a strength of the dTMT, the measurement of additional variables for examining the applicability to the clinical field allowed the decomposition of cognitive abilities and observation of changes in performance during the task. The second part (Part II: exercise intervention) investigated the acute effects of exercise-induced cortical activation on cognitive performance using the dTMT. We used functional near-infrared spectroscopy (fNIRS) to measure hemodynamic response in the brain's frontal lobe and motor cortex for immediate and sustained effects of acute exercise with different exercise intensities. Finally, the interaction of these two parts (assessment and exercise intervention) and the neural mechanisms led to the following discussions. First, we confirmed the value of digital assessment as an early detection tool for motor and cognitive impairment. Second, we identified which exercise intervention positively induces cortical changes in our brain by accompanying the improvement of cognitive performance. The present thesis discussed the role of digital measurement and exercise intervention in maintaining our health and in which direction we should go for our future.