title: Reduced short latency afferent inhibition in diffuse axonal injury patients with memory impairment.
abstract: The present study used short interval intracortical inhibition (SICI), intracortical facilitation (ICF), and short latency afferent inhibition (SAI) to evaluate motor cortex excitability in 16 diffuse axonal injury (DAI) patients with memory impairment and compared the data with those of 16 healthy controls. SAI was reduced in patients compared with controls (92+/-12 versus 39+/-11% of the test size; p<0.0001, unpaired t-test). DAI patients tended to have a high resting motor threshold (RMT) and less pronounced SICI and ICF than controls, but these differences were not significant. A single oral dose (3mg) of donepezil, an acetylcholinesterase inhibitor that is commonly used to treat Alzheimer's disease (AD), improved SAI in DAI patients with wide individual variations that ranged from an increase of 77-18% of test size. These findings suggest that measuring SAI may provide a means of probing the integrity of cholinergic networks in an injured human brain.
authors.affiliation: Department of Neurosurgery, School of Medicine, Oita University, 1-1 Idaigaoka, Hasamamach, Oita 879-5593, Japan. fujiki@med.oita-u.ac.jp
authors.forename: Minoru
authors.initials: M
authors.lastname: Fujiki
authors.forename: Takamitsu
authors.initials: T
authors.lastname: Hikawa
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Abe
authors.forename: Keisuke
authors.initials: K
authors.lastname: Ishii
authors.forename: Hidenori
authors.initials: H
authors.lastname: Kobayashi
mesh_terms: D000328:Adult; D000344:Afferent Pathways / Q000187:drug effects / Q000503:physiopathology* / Q000528:radiation effects; D004056:Differential Threshold / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D020833:Diffuse Axonal Injury / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology*; D000077265:Donepezil; D005260:Female; D006801:Humans; D007189:Indans / Q000008:administration & dosage; D008297:Male; D008569:Memory Disorders / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology*; D009044:Motor Cortex / Q000187:drug effects / Q000503:physiopathology* / Q000528:radiation effects; D009433:Neural Inhibition / Q000502:physiology* / Q000528:radiation effects; D018697:Nootropic Agents / Q000008:administration & dosage; D010880:Piperidines / Q000008:administration & dosage; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D050781:Transcranial Magnetic Stimulation / Q000379:methods
chemical_list: D007189:Indans; D018697:Nootropic Agents; D010880:Piperidines; D000077265:Donepezil