Associations of congruence and exposure sequence with indoor environmental quality perception and heart rate variability in an immersive residential experiment

This is the authors' abstract. We don't add key points for this paper.

Immersive experiments allow controlled manipulation of indoor environmental features while preserving a realistic sense of space; however, responses obtained across repeated exposures may also vary with participant context and progression through the experimental sequence. This study examined whether subjective environmental perceptions and heart rate variability (HRV) were associated with residential-context similarity, presentation position across repeated exposures, and directional changes in living-room and window size between consecutive scenes. Thirty-three adults completed four immersive residential sessions and were classified as Match (n = 25) or Mismatch (n = 8) based on whether the overall configuration of their home living room broadly matched the common simulated layout. Generalized estimating equations addressed residential context, presentation position, and directional transitions; additional analyses examined pre-exposure baselines, baseline-referenced changes, and exploratory principal component analysis. The residential-context group was not associated with scene-related subjective or physiological responses, although the Mismatch group showed higher resting lnRMSSD and lnSDNN before scene exposure. Primary analysis linked presentation position to lnRMSSD after correction, but not subjective perceptions; sensitivity analyses identified variation in pre-exposure lnLF/HF and baseline-referenced ΔlnRMSSD and ΔlnLF/HF. An HRV-dominant principal component also varied across presentation positions, whereas subjective environmental perceptions and the perception-dominant component did not. Directional changes in living-room and window size showed no associations that remained significant after multiplicity correction. These findings indicate that physiological responses may vary systematically across repeated immersive exposures even when concurrent subjective environmental perceptions do not. Presentation position should therefore be considered explicitly in the design and analysis of repeated immersive building-environment experiments.