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Vibration sensitivity of slowly and rapidly adapting cutaneous mechanoreceptors in the human foot and leg
HUMAN
RESPONSE
TO
VIBRATION
543
E. Ribit-Ciscar, J. P. Vedel and J. P. Roll 1989 Neuroscience Letters 104,130-135.Vibration sensitivity of slowly and rapidly adapting cutaneous mechanoreceptors in the human foot and leg. (6 pages, 2 figures, 0 tables, 22 references) (in English) Authors’ Abstract. The activities of 30 rapidly adapting cutaneous receptors (FA) and 23 slowly adapting cutaneous receptors (SA) were recorded from the lateral peroneal nerve using the microneurographic method. Their sensitivity to mechanical vibrations with constant amplitude applied at various frequencies to the center of the receptive field was studied. These two populations of cutaneous receptors were found to be very sensitive to this stimulus: they could be driven in a one to one manner up to between 100 and 200 Hz. The difference lay in the response observed when the vibration frequency was increased to above this critical value: the FA receptors sharply stopped firing, whereas the SA receptors became progressively unlinked from the stimulus. The effects of vibration on the physiological messages were also studied. The results showed that the messages coding the properties of tactile stimuli were either completely or partly masked by the receptor response to vibration. These vibration-induced modifications of cutaneous sensory messages might be at least partly responsible for the sensorimotor alterations observed when subjects are exposed to vibration. Topics: Vibration Sense (General); Perceptual Mechanisms ( Touch). I. Pyykkii, K. Koskimies, J. Starck, J. Pekkarinen, M. Farkkila and R. Inaba 1989 British Risk factors in the genesis of sensorineural hearing loss in Finnish forestry workers. (8 pages, 6 figures, 1 table, 52 references) (in English) Authors’ Abstract. A detailed analysis of risk factors for the development of sensorineural hearing loss (SNHL) was carried out in 199 forest workers. The hearing threshold of both ears at 4000 Hz was measured, and the effect of age, exposure to noise, blood pressure, presence or vibration induced white finger (VWF), tobacco smoking, plasma LDL-cholesterol concentration and consumption of drugs were evaluated by multiple linear regression analysis. Aging was the major risk factor, followed by exposure to occupational noise and the presence of VWF. Plasma LDL-cholesterol concentration and the use of antihypertensive drugs also correlated significantly with SNHL. These main factors were able to explain about 28% of the SNHL variance. Additional factors in the analysis, including smoking, systolic diastolic blood pressure, and consumption of salicylates did not significantly contribute to the genesis of SNHL. Topics: Vibration Syndrome ( Vibration-Znduced White Finger); Combined Stress ( Vibration Journal of Industrial Medicine 46(7), 439-446.
and Noise), Perceptual Mechanisms
(Hearing).
Note: copies of all papers in this section will be found in the Human Response to Vibration Literature Collection at the Institute of Sound and Vibration Research, The University of Southampton. The papers may be used by persons visiting the Institute. Contributions to the Literature Collection are requested. They should be sent to Dr M. J. Grifin, Human Factors Research Unit, Institute of Sound and Vibration Research, The University, Southampton SO9 5NH, England.
RESPONSE
TO
VIBRATION
543
E. Ribit-Ciscar, J. P. Vedel and J. P. Roll 1989 Neuroscience Letters 104,130-135.Vibration sensitivity of slowly and rapidly adapting cutaneous mechanoreceptors in the human foot and leg. (6 pages, 2 figures, 0 tables, 22 references) (in English) Authors’ Abstract. The activities of 30 rapidly adapting cutaneous receptors (FA) and 23 slowly adapting cutaneous receptors (SA) were recorded from the lateral peroneal nerve using the microneurographic method. Their sensitivity to mechanical vibrations with constant amplitude applied at various frequencies to the center of the receptive field was studied. These two populations of cutaneous receptors were found to be very sensitive to this stimulus: they could be driven in a one to one manner up to between 100 and 200 Hz. The difference lay in the response observed when the vibration frequency was increased to above this critical value: the FA receptors sharply stopped firing, whereas the SA receptors became progressively unlinked from the stimulus. The effects of vibration on the physiological messages were also studied. The results showed that the messages coding the properties of tactile stimuli were either completely or partly masked by the receptor response to vibration. These vibration-induced modifications of cutaneous sensory messages might be at least partly responsible for the sensorimotor alterations observed when subjects are exposed to vibration. Topics: Vibration Sense (General); Perceptual Mechanisms ( Touch). I. Pyykkii, K. Koskimies, J. Starck, J. Pekkarinen, M. Farkkila and R. Inaba 1989 British Risk factors in the genesis of sensorineural hearing loss in Finnish forestry workers. (8 pages, 6 figures, 1 table, 52 references) (in English) Authors’ Abstract. A detailed analysis of risk factors for the development of sensorineural hearing loss (SNHL) was carried out in 199 forest workers. The hearing threshold of both ears at 4000 Hz was measured, and the effect of age, exposure to noise, blood pressure, presence or vibration induced white finger (VWF), tobacco smoking, plasma LDL-cholesterol concentration and consumption of drugs were evaluated by multiple linear regression analysis. Aging was the major risk factor, followed by exposure to occupational noise and the presence of VWF. Plasma LDL-cholesterol concentration and the use of antihypertensive drugs also correlated significantly with SNHL. These main factors were able to explain about 28% of the SNHL variance. Additional factors in the analysis, including smoking, systolic diastolic blood pressure, and consumption of salicylates did not significantly contribute to the genesis of SNHL. Topics: Vibration Syndrome ( Vibration-Znduced White Finger); Combined Stress ( Vibration Journal of Industrial Medicine 46(7), 439-446.
and Noise), Perceptual Mechanisms
(Hearing).
Note: copies of all papers in this section will be found in the Human Response to Vibration Literature Collection at the Institute of Sound and Vibration Research, The University of Southampton. The papers may be used by persons visiting the Institute. Contributions to the Literature Collection are requested. They should be sent to Dr M. J. Grifin, Human Factors Research Unit, Institute of Sound and Vibration Research, The University, Southampton SO9 5NH, England.