Table 1.

Previous meditation studies involving autonomic nervous responses.

Ref.	Meditation Name	Finding
[4]	Hindu tantric meditation	Increased HR
[5]	Deity (Vajrayana tantric)	Decreased HF
[5]	Vipassana	Increased HF and decreased LF/HF
[5]	Shamatha (Kasina visualization)	Decreased LF/HF
[6]	Zen concentrative meditation	Increased HF and decreased LF/HF
[7]	Concentration meditation: focuses on the breath to achieve the Samadhi state	R–R time series signal tends to shift toward a specific frequency to form a resonant peak
[8]	Inward-attention meditation	Decreases in LF/HF ratio and LF norm; increase in HF norm
[6]	Zen concentrative meditation	Increased HF and decreased LF/HF
[9]	Intensive vipassana meditation	Increased HF
[5]	Deity (Vajrayana tantric)	Decreased HF
[5]	Vipassana	Increased HF and decreased LF/HF
[5]	Shamatha (Kasina visualization)	Decreased LF/HF
[10]	Yoga	Increased HF; decreased LF; decreased LF/HF decrease