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An impairment in sniffing contributes to the olfactory impairment in Parkinson's disease

Sobel, Noam and Thomason, Moriah E. and Tanner, Caroline M. and Tetrud, James W. and Bower, James M. and Sullivan, Edith V. and Gabrieli, John D. E. (2001) An impairment in sniffing contributes to the olfactory impairment in Parkinson's disease. Proceedings of the National Academy of Sciences of the United States of America, 98 (7). pp. 4154-4159. ISSN 0027-8424. PMCID PMC31195.

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Although the presence of an olfactory impairment in Parkinson's disease (PD) has been recognized for 25 years, its cause remains unclear. Here we suggest a contributing factor to this impairment, namely, that PD impairs active sniffing of odorants. We tested 10 men and 10 women with clinically typical PD, and 20 age- and gender-matched healthy controls, in four olfactory tasks: (i) the University of Pennsylvania smell identification test; (ii and iii) detection threshold tests for the odorants vanillin and propionic acid; and (iv) a two-alternative forced-choice detection paradigm during which sniff parameters (airflow peak rate, mean rate, volume, and duration) were recorded with a pneomatotachograph-coupled spirometer. An additional experiment tested the effect of intentionally increasing sniff vigor on olfactory performance in 20 additional patients. PD patients were significantly impaired in olfactory identification (P < 0.0001) and detection (P < 0.007). As predicted, PD patients were also significantly impaired at sniffing, demonstrating significantly reduced sniff airflow rate (P < 0.01) and volume (P < 0.002). Furthermore, a patient's ability to sniff predicted his or her performance on olfactory tasks, i.e., the more poorly patients sniffed, the worse their performance on olfaction tests (P < 0.009). Finally, increasing sniff vigor improved olfactory performance in those patients whose baseline performance had been poorest (P < 0.05). These findings implicate a sniffing impairment as a component of the olfactory impairment in PD and further depict sniffing as an important component of human olfaction.

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Additional Information:© 2001 The National Academy of Sciences. Communicated by Gordon H. Bower, Stanford University, Stanford, CA, February 6, 2001 (received for review December 2, 2000). N.S. thanks the Parkinson’s Institute staff and 40 anonymous PD patients for their helpfulness; Gordon Bower for his editorial help; Ilana Hairston, Eve DeRosa, and Adam Anderson for their advice on the manuscript; and Elite Ha Arak for continued support. This work was supported by National Institutes of Health Grants AA10723 (to E.V.S) and NS40467 and ES10803 (to C.M.T.).
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Issue or Number:7
PubMed Central ID:PMC31195
Record Number:CaltechAUTHORS:20141124-133435273
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Official Citation:Sobel, N., Thomason, M. E., Stappen, I., Tanner, C. M., Tetrud, J. W., Bower, J. M., . . . Gabrieli, J. D. E. (2001). An impairment in sniffing contributes to the olfactory impairment in Parkinson's disease. Proceedings of the National Academy of Sciences, 98(7), 4154-4159. doi: 10.1073/pnas.071061598
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:52113
Deposited By: Jason Perez
Deposited On:25 Nov 2014 00:26
Last Modified:04 Jun 2020 18:59

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