Literature Review on Environmental Psychology: The Influence of Nature Therapy on the Human Brain

A comprehensive review of recent studies proving how exposure to forest environments (Shinrin-yoku) heals stress and alters brain activity.

Literature Review on Environmental Psychology: The Influence of Nature Therapy on the Human Brain

With urbanization reaching historic peaks, mental health disorders related to anxiety and chronic stress have spiked. A growing field within environmental science and neuroscience is examining nature therapy, particularly the Japanese practice of Shinrin-yoku (forest bathing). This literature review analyzes scientific evidence demonstrating how nature exposure physically alters brain architecture.

Key Findings from Environmental Psychology

1. Deactivation of the Subgenual Prefrontal Cortex

Neuroimaging research has demonstrated that walking in natural forest settings leads to a reduction in neural activity in the subgenual prefrontal cortex—the area of the brain associated with rumination, obsessive thoughts, and depression. A 90-minute nature walk physically quietens the brain networks responsible for worry.

2. Balancing the Autonomic Nervous System

Forest therapy trials show a significant decrease in sympathetic nervous activity (the fight-or-flight system) and a corresponding increase in parasympathetic activity (the rest-and-recovery system). This biological shift is reflected in lower heart rates, decreased cortisol levels, and lower blood pressure.

3. Phytoncides and Immune Boosting

Phytoncides are natural volatile compounds released by coniferous trees. Inhaling these organic chemicals during forest bathing has been proven to increase the activity and count of Natural Killer (NK) cells in the human immune system, boosting anti-cancer proteins and strengthening disease defense.

4. Cognitive Restoration Theory (Attention Restoration Theory)

Modern screens demand \"directed attention,\" which quickly causes cognitive fatigue. Forests, on the other hand, provide \"soft fascination\"—capturing our attention gently through wind movements, tree rustling, and bird calls. This effortless cognitive engagement allows the brain's focus mechanisms to rest and fully restore.

Conclusion

Nature therapy is not just a leisure activity; it is a vital, scientifically backed therapeutic intervention. The evidence shows that nature exposure alters brain activity, balances hormones, and strengthens the immune system. Integrating nature walks into urban planning and clinical therapy represents a modern approach to public mental health care.