MadSci Network: General Biology |
Dear Cherry, Thank you for your very interesting question. The human voice is a wonderful instrument and it can carry meaning not only through words, but also through loudness (volume), prosody (rhythm) and of course pitch which, as you know, is a measure of how high or low a voice is. Pitch is mainly determined by the speed of vibration of the vocal folds: The higher the pitch the faster the rate of vibration and the lower the pitch the slower the rate of vibration. When we are angry, many biological functions (for example our heart beat or respiratory rate) accelerate as our sympathetic nervous system prepares our body for the "fight or flight" response". The vibration rate of our vocal folds is affected in a similar manner, and the pitch of our voice therefore automatically rises. Increased muscle tenseness of the laryngeal musculature in high arousal situations also limit vocal cord tension and larynx position, making it difficult to vary the pitch of the voice. I hope this answers your question. Cheers! Benoit
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