Analysis of Individual Variations in Autonomic Responses to Urban and Forest Environments

Figure 2

Histograms showing the low frequency/high frequency ratio (ln[LF/HF]) of heart rate variability in urban and forest environments. (a) ln(LF/HF) at urban sites, (b) ln(LF/HF) at forest sites, and (c) difference in ln(LF/HF) between urban and forest sites.

(a) Urban environment

(b) Forest environment

(c) Difference (urban-forest)