Assessment of pharyngeal sensitivity to mechanical stimuli using psychophysical and electrophysiological techniques.
The investigation was aimed to assess pharyngeal sensitivity by means of intensity ratings and event-related potentials (ERPs) to mechanical stimulation. Twenty healthy subjects participated (14 female, mean age 23.6 years). Both intensity ratings and ERP were obtained in response to three intensities of mechanical stimuli (air puffs) applied to the nasal cavity or the pharynx. Test-retest reliability was investigated for two sessions performed on different days. The study provided the following: (1) intensity ratings of nasal or pharyngeal stimuli increased with increasing stimulus intensity (P < 0.001); (2) they also exhibited a significant test-retest reliability (r </= 0.78) which was best for higher stimulus intensities; (3) ERP amplitudes increased and latencies shortened with increasing stimulus intensity (factor 'intensity': P < 0.013); (4) test-retest reliability was best at centro-frontal recording sites where significant correlations were found for both ERP amplitudes and latencies; (5) ERP to pharyngeal stimulation correlated significantly with perceived stimulus intensity (e.g., latency N1 at Cz: r = -0.73, P = 0.001). In conclusion, mechanical stimulation of the pharynx can be applied to reliably elicit ERPs which are related to both stimulus intensity and intensity ratings. This model may be useful in the investigation of cough-related changes in pharyngeal sensitivity.
Hummel
Thomas
T
Department of Otorhinolaryngology, University of Dresden Medical School, Fetscherstr. 74, Dresden, 01307, Germany. thummel@rcs.urz.tu-dresden.de
Haenel
Tobias
T
Hull
David
D
D000328:Adult; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D010614:Pharynx / Q000502:physiology*; D013314:Stress, Mechanical