In the other study relevant to physiological relaxation of a bonsai, 24 Japanese male patients with spinal cord injuries who had experienced mental and physical stress viewed a miniature potted 10-year-old Japanese cypress bonsai (40 × 20 × 5 cm), and the changes in oxy-Hb concentration in the prefrontal cortex (NIRS) and HRV were used as indexes of physiological relaxation [43]. This evidence concerns the gene GSTM1 and spinal cord injury.