Toward a mental health research framework for natural and built environments

Exposure to natural environments and biophilic design features has been associated with improvements in cognitive, affective, and physiological functioning. Yet, the mechanisms through which physical environments influence mental health remain poorly specified. Research in these domains has relied heavily on environmental psychology theories such as Attention Restoration Theory (ART) and Stress Reduction Theory (SRT), which describe cognitive and affective benefits but employ comparatively underdefined constructs and lack mechanistic specificity. The absence of a systematic mental health framework limits theoretical integration, measurement precision, and translation of findings to architectural practice. This paper proposes the National Institute of Mental Health's Research Domain Criteria (RDoC) as a contemporary framework for organizing and investigating the mental health effects of nature exposure (NE) and biophilic design (BD). The RDoC conceptualizes mental functioning as an interplay of biobehavioral systems—including Positive Valence, Negative Valence, Cognitive Systems, and three additional domains—measured across multiple units of analysis (levels of specificity). We argue that environmental exposures may influence mental health through coordinated modulation of these systems and propose a cross-domain pattern in which NE and BD increase reward-related processing and cognitive control while reducing threat-related processing, reversing patterns associated with psychopathology risk. Empirical findings from prior studies and recent work using virtual and photographic nature exposure provide preliminary support for this conceptual model. We further outline research directions for advancing mechanistic understanding, including investigation of specific RDoC constructs, identification of neural circuitry mediating environmental effects, and integration of architectural variables into RDoC-informed experimental designs. A candidate neural mechanism, termed Present Moment Focus, is discussed as a potential circuit-level pathway linking environmental perception to cognitive and affective modulation. Incorporating built environment research into RDoC models may enable systematic mapping of architectural features to mental health systems and support the development of evidence-based design strategies. Conceptualizing environmental influences within a modern mental health framework offers a pathway to cumulative knowledge about how natural and built environments shape mental functioning. Integrating neuroscience, psychology, and architecture through RDoC-informed approaches may ultimately support the design of environments that intentionally promote mental health and well-being.