Author: Milena A. Guziak

Abstract

Abstract

A growing body of research suggests that contact with natural environments supports human well-being across psychological, cognitive, emotional, and physiological domains. Yet the mechanisms underlying these effects remain multidimensional and cannot be fully explained by any single theory. This article examines several influential theoretical perspectives that have shaped contemporary understanding of the relationship between nature and human well-being, including the Biophilia Hypothesis, Attention Restoration Theory, Stress Reduction Theory, Psychoevolutionary Theory, Nature Relatedness and Nature Connectedness, and the framework of Favorite Places. Each of these perspectives offers a distinct yet complementary account of how natural environments may influence human functioning, whether through evolutionary affiliation with life, cognitive restoration, psychophysiological stress recovery, emotional regulation, subjective connectedness, or attachment to meaningful places.

Rather than treating these theories as competing explanations, the article argues that they are best understood as overlapping and mutually enriching frameworks. Taken together, they suggest that nature may promote well-being by reducing stress, restoring directed attention, eliciting positive affect, strengthening identity and belonging, supporting self-regulation, and fostering a deeper sense of relationship with the more-than-human world. The article further considers how these theoretical perspectives may be integrated in the context of forest therapy, forest bathing, and Shinrin Yoku, where guided engagement with the forest provides a practical setting in which multiple restorative pathways may converge. In doing so, the article aims to build a bridge between environmental psychology, health research, and applied forest therapy practice.

10.65410/syjI120230415en6

Abstract

Understanding the effects of exposure to forest environments requires attention not only to subjective experience, but also to the physiological processes through which restoration, stress regulation, and well-being may be expressed in the body. Although participants in guided forest therapy sessions often report feeling calmer, lighter, more grounded, mentally refreshed, or even sleepy, such experiences may also be accompanied by measurable biological changes. For this reason, physiological markers have become an important focus in research on forest-based interventions.

This chapter examines physiological markers as one means of understanding how the body responds to stress, relaxation, environmental exposure, and emotional regulation in the context of forest therapy. Particular attention is given to hormonal markers associated with the stress response, especially adrenaline, noradrenaline, and cortisol; inflammatory markers such as interleukins, tumor necrosis factor, and C-reactive protein; and autonomic indicators, including heart-rate variability. The chapter also considers the interaction between the hypothalamic-pituitary-adrenal axis, the autonomic nervous system, and inflammatory processes, highlighting their relevance for understanding recovery and adaptive regulation.

Rather than reducing the forest therapy experience to biological measurement alone, this  article situates physiological markers within a broader psychophysiological framework. These indicators do not capture the full meaning of well-being or the therapeutic encounter in the forest, yet they offer valuable insight into how the body may shift from states of heightened activation toward regulation, recovery, and balance. In this way, the chapter aims to bridge subjective reports of restoration with measurable physiological processes, contributing to a more integrated understanding of forest therapy and its potential relevance for human health and well-being.

Abstract

his article examines the role of olfaction as a key pathway through which forest environments may influence human physiology, emotion, and well-being. While guided forest therapy and Shinrin Yoku are often discussed in relation to visual beauty, attentional restoration, and symbolic or experiential connection with nature, the sense of smell provides a particularly direct route by which the forest enters the human body and nervous system. Through the inhalation of plant-derived volatile compounds, including phytoncides, the forest atmosphere may affect sensory perception, emotional processing, autonomic regulation, and broader psychophysiological states.

The article develops this process through the concept of a circle of influence, understood as the dynamic sequence by which plants release volatile compounds into the atmosphere, these compounds are inhaled and detected through the olfactory system, and olfactory signals are subsequently transmitted to neural, emotional, and autonomic pathways that shape bodily and psychological response. In this sense, forest exposure is approached not as a passive backdrop to human experience, but as an active atmospheric encounter linking environment and organism.

The discussion begins with the anatomy and physiology of olfaction, including the dual nature of smell, the structure of the olfactory system, and the transduction of odorant molecules into neural signals. It then considers the privileged neuroanatomical position of olfaction, whose pathways provide relatively direct access to limbic and hypothalamic regions implicated in memory, emotion, endocrine function, and autonomic balance. The article further explores how inhaled aromatic compounds may participate in an olfactory-limbic-autonomic pathway associated with relaxation and shifts toward parasympathetic regulation. Forest-derived volatiles and selected essential-oil compounds are discussed as examples of how scent may contribute to reduced arousal, calmer affective tone, and physiological settling. At the same time, the article maintains a cautious perspective, emphasizing that these effects should not be reduced to isolated chemical events, but understood within the wider multisensory and ecological context of forest experience.