Conclusions
CORTEX
The changes in physiological and psychological responses among patients with GD who were exposed to nature and city sounds were examined. This study revealed the following results: (1) listening to nature sounds significantly decreased the oxy-Hb concentrations in the bilateral prefrontal cortex, thereby promoting a pleasant and relaxed state; (2) based on the assessment using the modified SD method, nature-related stimuli significantly increased comfort, relaxation, and natural feelings; and (3) stimulation with nature sounds significantly decreased the A–H, C–B, F–I, T–A, and TMD subscale scores. However, the V–A and F subscale scores increased remarkably. Exposure to nature sounds showed physiological relaxation and other positive responses among individuals with GD. Thus, nature sounds have a stress-reducing effect on patients with GD, as well as healthy individuals.