Differences in Brain Activity During Real and Virtual Reality Motor Tasks in Normal Healthy Individuals

This study aimed to clarify the differences between brain activity during virtual reality and real motor tasks. Twelve healthy adults participated in this study. Near-infrared spectroscopy (NIRS) was used to measure brain activity, and a total of 34 channels, 17 channels each, centred on the bilateral motor cortex, were used as measurement sites. Two types of motor tasks were used: a real Box and Block test (R-BBT) and a virtual reality Box and Block test (VR-BBT). In both motor tasks, an increase in oxy-haemoglobin (O₂Hb) and a slight decrease in deoxy-haemoglobin (HHb) levels were observed in the central region of the participant's motor cortex. The O₂Hb in the motor cortex during R-BBT increased at the beginning of the task, rapidly decreased, and remained at a low value. Conversely, the amount of O₂Hb in the motor cortex during the VR-BBT remained high throughout the task. In addition, O₂Hb in the dorsal prefrontal cortex during the VR-BBT was significantly higher than during the R-BBT. This study indicates that brain activity differs significantly between real and virtual reality motor tasks, even for similar tasks.