Biophilic interventions in real and virtual environments reduce stress during cognitively demanding tasks

: Biophilic design integrates natural elements into indoor environments to mitigate the negative effects of urbanization on human well-being. However, its efficacy in reducing stress during demanding tasks and the extent to which virtual biophilic interventions replicate real-world benefits remain unclear. We investigated whether a small-scale biophilic intervention-a removable, medium-sized living wall (LW) containing plants-reduces stress during performance of a cognitively demanding working memory task and positively influences emotions and environmental judgment. Its effects were compared to those of a virtual simulation. Forty-one participants, assigned to either a real (N = 21) or virtual (N = 20) environment, completed two sessions: one with the LW, one with an object-filled shelf. Heart rate variability, self-reported emotions, and environmental evaluations were collected. The results show higher physiological relaxation during the task and more favorable environmental ratings when exposed to the LW, regardless of the type of environment. Positive emotions were higher only in the real environment, suggesting a stronger emotional impact of real biophilic elements. These findings are of practical relevance for places where managing stress during demanding activities is crucial (offices, schools) or where access to nature is limited (hospitals, confined spaces).