Abstract: Objective To investigate the self-regulation of the autonomic nervous system following the cognitive stress tests after heart rate variability (HRV) biofeedback therapy in patients with post-stroke depression (PSD). Methods From May, 2013 to December, 2015, 48 patients with PSD were randomly divided into feedback group (n=25) and control group (n=23). The feedback group received HRV biofeedback therapy, while the control group only received relaxation therapy without feedback signal. HRV parameters were tracked during the cognitive stress test in quiet baseline state, cognitive stress state, and resting state before and after treatment. Results Under the stress condition, the low frequency of both groups increased during the first cognitive test, and the rate was higher in the control group than in the feedback group (P=0.02). The heart rates during the second cognitive test decreased in the feedback group, while increased in the control group (P=0.05). After rest, the heart rate of the feedback group decreased below the baseline (P=0.02). Conclusion During the cognitive stress test, HRV biofeedback therapy can achieve a dynamic balance between sympathetic and parasympathetic nerves by reducing sympathetic sensibility, which improved patients' adaptive capacity to cope with their internal physiological environment and external environmental pressures.

Key words: stroke, heart rate variability, biofeedback, stress test