Neurophysiological correlates of senile dementia: I. Motor and sensory nerve conduction velocity

Abstract

SUMMARYThis paper describes an investigation into the relationship between senile dementia and slowing of peripheral nerve conduction velocity. Twenty-eight demented patients and 19 controls were studied. Each patient was rated clinically and given a battery of simple psychological tests in addition to the physiological recordings. The results were as follows: (1) Motor nerve conduction was slower in the demented group than in the control group but this difference was not significant. (2) When subjects were divided according to their dementia score, those with scores above 7 were found to have motor nerve conductions which were significantly slower than those with scores of 7 or less. (3) There was a significant correlation between the severity of the dementia as measured by the rating scale and the psychological tests and the degree of slowing of motor nerve conduction. (4) In those patients who were retested after one year, increase in dementia was significantly correlated with a further slowing of conduction in motor nerves. (5) The possible role of vitamin deficiency was investigated in a small sub-group of demented patients. Deficiencies of thiamine, nicotinic acid, and vitamin B12were not thought to be important but some patients had low folate levels. The significance of these results is discussed.

Postural Set for Balance Control is Normal in Alzheimer's but not in Parkinson's Disease

“…The normal onset latency of responses in the legs of Parkinson subjects is consistent with previous studies (12,17). The on set latency of responses in the Alzheimer subjects were also not different from the other groups, although delayed motor and sensory nerve conduction velocities have been reported (19). Even the four most demented subjects in our study had normal response latencies compared to the healthy control group.…”

Psychomotor performance in presenile dementia

“…Since the distinction between Alzheimer's disease and senile dementia is somewhat dubious, it is likely that slow motor nerve conduction will be found in Alzheimer's disease. However, the extent of the slowing of motor nerve conduction observed by Levy et al (1970) is far from sufficient to provide a total explanation for the present results.…”

“…Another factor that could help to explain retardation in the execution of movements lies in the finding of Levy et al (1970) that there is an inverse correlation between the degree of dementia and speed of motor nerve conduction in patients with senile dementia. Since the distinction between Alzheimer's disease and senile dementia is somewhat dubious, it is likely that slow motor nerve conduction will be found in Alzheimer's disease.…”

Key papers in geriatric psychiatry series editor: Alistair burns peripheral motor nerve conduction in elderly demented and non‐demented psychiatric patients

“…This first experiment led to a further one in which cognitive function was correlated with slowing of nerve conduction (Levy et al, 1969(Levy et al, . 1970 and later with sensory evoked responses (Levy ef d., 1971).…”