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excitotoxic- and oxidative-stress-induced injury, Hcy, neurodegenerative disorders needs to be explored. [42]
especially eHcy, can be neurotoxic. [4,37-39] Nevertheless, our finding of central conduction slowing
in adults with eHcy suggests clinically relevant
Elevated plasma level of homocysteine has been significance and warrants further investigation. The
observed in a number of neurological disorders limitation of this report was a retrospective study with
including stroke, [1,2] Alzheimer’s disease, Parkinson’s a small number of subjects.
[5]
disease, and amyotrophic lateral sclerosis. In
[7]
[8]
addition, eHcy may also play a role in psychiatric In summary, our pilot study on adults with isolated
disorders, such as depression, [6,9-12] bipolar disorders eHcy showed neurophysiologic evidence of slow
and schizophrenia. [13,14] Importantly, eHcy has been central conduction involving the large fibers in the
linked to cognitive impairment and dementia. [3,4] The somatosensory, but not the visual and auditory, white
findings of slowness of the central conduction in our matter pathways. The neurophysiologic changes may
study may suggest an electrophysiologic background occur in parallel to eHcy-induced central processing
for the central process slowing relevant to memory and decline. Additional large cohort studies may be needed
cognitive functions. Notably, VEP was performed using to validate the finding.
two different modalities with only one out of 7 subjects
showing abnormality. It is not clear the reason why ACKNOWLEDGMENTS
visual and auditory pathways were spared. It may be
related to the susceptibility of eHcy-induced nerve fiber This article is dedicated to Mrs. Ethel Lombard for her
damage or the tolerability of the fibers to eHcy-induced outstanding service to the Department of Neurology at Temple
University Hospital for 60 years.
insults. An alternative explanation is that there may be
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