The Brain Networks Indices Associated with the Human Perception of Comfort in Static Force Flexion Tasks

Lina Ismail^1*Waldemar Karwowski^2*

• ¹Arab Academy for Science, Technology and Maritime Transport (AASTMT), Alexandria, Egypt
• ²University of Central Florida, Orlando, Florida, United States

The perception of physical comfort is one of the crucial workplace design parameters. Most comfort perception studies have mainly relied on subjective assessments and biomechanical techniques, with limited exploration on neural brain activity with regard to physical comfort perception. The current study investigates the research gap by integrating the rating of perceiving physical comfort (RPPC) with brain network indices in an arm flexion task across different force levels. The applied arm forces, EEG-based neural responses, and the RPPC were measured, and the corresponding theory network indices were calculated. The following correlations were evaluated: (a) RPPC and applied forces, (b) theory network indices and applied forces, and (c) RPPC and theory network indices. Results for (a) revealed a significant negative correlation between RPPC and the applied force for the arm flexion task. This shows that as the applied force difficulty increases to an extremely hard level, the perceived of physical comfort decreases till it reaches no comfort level. Results for (b) showed a positive correlation between the force applied and global efficiency for the alpha network coherence during an extremely hard flexion task. In contrast, a negative correlation was found between applied force and path length for beta coherence during a light flexion task. Finding from (b) suggests that the brain is more efficient in transmitting information related to cognitive functioning during a highly demanding force flexion task than a light task. Results for (c) showed a negative correlation between RPPC and global efficiency for alpha coherence during an extremely hard flexion task. Moreover, a positive correlation was observed between RPPC and local efficiency for beta coherence during a somewhat hard flexion task. Findings from (c) indicate that perceiving a low-comfort physical task might increase task alertness, and the corresponding neural network showed a high level of internal brain organization.