In the modern society, the negative impacts of stress and anxiety have been very apparent. So reduction of stress and its after-effects is a very important facet of studies on the human mind. It has been widely seen that music has a mitigating impact on the effects of stress and anxiety. This article deals with the issue of reduction of stress, through a signal processing viewpoint. As a method of studying the effects of stress and anxiety, we have taken the HRV (heart rate variability) signals obtained from the subjects in two stages: first, when the subjects are solving puzzles, and second, in a post-music state. These signals have been analysed using 2-D Poincaré plots which have shown satisfactory results from a mathematical, as well as human physiological point of view.

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2-D Poincaré plots HRV Signal Stress Condition Post-Music Condition.