Frontal lobe activity during the performance of spatial tasks: fNIRS study

Abstract

[Purpose] The aim of this study was to verify frontal lobe activity in healthy individuals during the performance of spatial tasks as part of a cognitive therapeutic exercise. [Subjects] Twelve healthy young adults participated in the experiment. [Methods] The spatial tasks were to differentiate the sizes of circles with different diameters. In actual practice, a therapist held the upper limbs of an experiment participant and passively traced 5 randomly appearing circles of differing sizes by moving only the participant's shoulder joint and then had the participant determine the order of the circles. Under control conditions, the participant was not asked to make this determination. Under both experimental and control conditions, the experiment participant was asked to close his or her eyes during the tasks. Functional near-infrared spectroscopy (fNIRS) was used for measurement, and relative changes in blood flow in the frontal lobe were measured. [Results] Blood flow in the premotor cortex and dorsolateral prefrontal cortex increased significantly (p<0.05) under spatial task conditions in comparison to control conditions. [Conclusion] This result suggests that the premotor cortex, which is responsible for motor learning, and the dorsolateral prefrontal cortex, which is responsible for working memory function, are activated during the performance of spatial tasks as part of cognitive therapeutic exercise.