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Effect of Normobaric and Hypobaric Hypoxia on Formant Characteristics of Human Voice

International Journal of Computer Applications
© 2015 by IJCA Journal
Volume 122 - Number 15
Year of Publication: 2015
Savita Sondhi
Munna Khan
Ritu Vijay
Ashok K. Salhan
S. K. Sharma

Savita Sondhi, Munna Khan, Ritu Vijay, Ashok K Salhan and S K Sharma. Article: Effect of Normobaric and Hypobaric Hypoxia on Formant Characteristics of Human Voice. International Journal of Computer Applications 122(15):32-37, July 2015. Full text available. BibTeX

	author = {Savita Sondhi and Munna Khan and Ritu Vijay and Ashok K. Salhan and S. K. Sharma},
	title = {Article: Effect of Normobaric and Hypobaric Hypoxia on Formant Characteristics of Human Voice},
	journal = {International Journal of Computer Applications},
	year = {2015},
	volume = {122},
	number = {15},
	pages = {32-37},
	month = {July},
	note = {Full text available}


Background: Hypoxia is an intensive environmental stressor which affects the psychophysiological state of an individual. It has been confirmed to influence the fundamental frequency of voice. This study aims to investigate the effect of different hypoxia conditions on formant characteristics of voice. Method: Eighteen volunteers recorded voice using a mobile phone in two phases. Study-1: Six subjects were exposed to normobaric hypoxia (NH) for four days in a normobaric chamber. For hypobaric hypoxia same subjects were airlifted to 11500 ft above sea level (SL) and stayed there for four days. Study-2: Out of twelve subjects, six test subjects exercised after NH exposure. Other six were control subjects. All 12 subjects were then airlifted to 11500 ft and stayed at this height for six days. Obtained data was analyzed using BLISS software. Result: No change in formant's frequency was observed after NH exposure or at high altitude (HA). Significant increase in formant's intensity was noted after NH exposure. Formant's intensity decreased on initial exposure to HA, however it increased after acclimatization. Percentage increase in the formant's intensity after NHE without exercise was more than that with exercise. Conclusion: Hypoxic stress changes voice parameters. Formant frequency is not affected by hypoxic stress.


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