ISSN:
1432-1106
Keywords:
Tactile air-puff stimulation
;
Face
;
Stimulus intensity
;
Somatosensory evoked potentials
;
Psycho-physical magnitude estimations
;
Mechanical properties of the skin
;
Human
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary Air-puff stimuli were applied to the skin of the face to obtain psychophysical and neurophysiological responses. Six levels of stimulus intensity above threshold were adopted for numerical magnitude estimation and for recording somatosensory evoked potentials (SEPs). A power function with an exponent of 0.71 provided an adequate description of the magnitude estimation values as a function of stimulus intensity, as was verified by the high correlation coefficient (r=0.86, P 〈 0.001). Six SEP components (N15, P20, N30, P40, N50 and P65) were recorded during the 100 ms following stimulation. Stimulus-amplitude functions of the various SEP components were well represented by power functions. The P20-N30 component had the highest power exponent (0.66) and also the highest correlation coefficient (r=0.55, P 〈 0.001). The SEP latencies as a function of stimulus intensity had negative power functions. The latency function of the P20 component had the largest negative power exponent (-0.10) and showed the highest negative correlation (r = — 0.62) with the stimulus intensity. These results suggest that processing of intensity information occurs at a relatively early stage within the central nervous system, and that both the amplitude and latency information encoded in the SEPs may contribute to stimulus processing.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00228192
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