Effect of Wood Indoor Environments on Human Psychophysiological Responses and Evaluation Indicators: A Review

Wood is recognized as a material with properties that promote emotional stability and physiological recovery in the human body and is receiving attention as an important constituent element of biophilic design. Accordingly, this study aimed to systematically analyze the effects of wood environments on human psychophysiological responses and to propose evaluation indicators applicable to future research and design. For this purpose, a literature search was conducted across the Scopus, PubMed, and Google Scholar databases for the period from January 1, 2000, to July 31, 2025, in accordance with the PRISMA 2020 guidelines; among a total of 16,148 documents, 24 experimental studies that met the selection criteria were included in the final analysis. The analysis results showed that exposure to wood environments generally tended to induce positive changes related to psychological stability and physiological relaxation responses. In the evaluation of psychological responses, the profile of mood states, positive and negative affect schedule, semantic differential, and visual analogue scale were primarily used. Physiological responses were evaluated through indicators such as heart rate variability (HRV), electroencephalography, cortisol, skin conductance level (SCL), and oxy-hemoglobin (oxy-Hb). As a result of applying these psycho-physiological indicators, decreases in negative emotional indicators, cortisol, SCL, and oxy-Hb were primarily identified, along with an increase in HRV-HF, an indicator of parasympathetic activity in the autonomic nervous system. Furthermore, some studies showed that psychological and physiological relaxation effects were relatively greater at moderate levels of wood application (approximately 40%–60%), although the optimal application range showed differences depending on the research design and exposure conditions. The psycho-physiological indicators derived through this review are expected to be utilized as basic data for establishing the scientific basis of future biophilic architectural design.