Society Proceedings / Clinical Neurophysiology 124 (2013) e19–e38
P2-60. Prism adaptation in spinocerebellar ataxia—Shinya Ohminami, Ryosuke Tsutsumi, Yuichiro Shirota, Shigeru Kitazawa, Motoaki Uchimura, Masahito Inoue, Shunichi Matsuda, Takahiro Shimizu, Nobuyuki Tanaka, Yaeko Ichikawa, Jun Goto, Shoji Tsuji, Yoshikazu Ugawa, Yasuo Terao, Ritsuko Hanajima (The University of Tokyo Hospital, Tokyo, Japan) The cerebellum is reported to play crucial roles in sensorimotor adaptation. Here we tried to assess this ability in spinocerebellar ataxia (SCA) patients, using the prism adaptation task. Wearing a wedge prism, reaching is initially shifted toward a displaced target. The error reduces gradually in about 10 trials. We applied this task to 21 SCA patients and age-matched 20 healthy controls to evaluate their sensorimotor adaptation ability. The task was throwing a ball to the target 150 cm away. Thirty baseline trials were followed by 30 adaptation trials with a prism, and another 30 trials after taking off the prism. Adaptation rate (AR) and aftereffect (AE), the oppositely directed error seen just after taking off the lens, were estimated. The prism produced 225 mm rightward shift. In wheelchair-bound SCA patients, neither significant adaptation (AR = 0; p = 0.11) nor AE (p = 0.07) was observed. In ambulant SCA patients, both AR (7.6% v.s. 8.9% in control; p = 0.50) and AE (86 mm v.s. 87 mm; p = 0.93) were normal. Elimination rate of AE was smaller (4.5% v.s. 11.3%; p = 0.013) in the patients. Our method was useful in evaluating sensorimotor adaptation ability in SCA patients. doi:10.1016/j.clinph.2013.02.105
P2-61. Evaluation of verbal fluency in Parkinson’s disease patients with deep brain stimulation—Tsubasa Sada, Yuka Watanabe, Madoka Okamura, Kenichi Hashimoto, Koichi Hirata (Dokkyo Medical University, Tochigi, Japan) Parkinson’s disease (PD) is a common disease of neurological disorders, and the motor symptoms of PD respond well to bilateral deep brain stimulation (DBS). Recent study, there are also reports of worsened verbal fluency, executive dysfunction, and processing speed with DBS. Whether subthalamic nuclei (STN) stimulation worsens there are under debate. The aim of this study was to explore the effects of STN stimulation verbal fluency as assessed with clinical neuropsychological tests. Eight patients treated with DBS were enrolled. Assessments were done both with the STN stimulation turned OFF and ON. In both test conditions, the following were assessed: speech, word fluency A, and B. The score of the word fluency test (WFT) of all patients have undergone DBS surgery significantly worsened as compared with before surgery. Five patients speech ware worsened, but three patients were improved when the STN stimulation was turned OFF. On the other hand, five patients were reduced the word fluency’s total score when the STN stimulation was turned OFF. In this sample, STN stimulation significantly worsened the result of the WFT. When the STN stimulation was turned OFF, it was reduced. These finding suggests that STN-DBS might be worse speech conditions and verbal fluency. doi:10.1016/j.clinph.2013.02.106
P2-66. Biomagnetic imaging of lumbar spine area using combined multiple measurements—Taishi Watanabe, Dai Ukegawa, Kosuke Okamoto, Shigenori Kawabata, Yoshiaki Adachi, Kensuke Sekihara (Tokyo Metropolitan University, Tokyo, Japan) The aim of this study is to provide a novel method for extending the field of view in lumber spine biomagnetic imaging.
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The extension of the field of view is achieved by combining multiple measurements using positional relationship between the sensor array and the subject’s body; the relationship is obtained using marker measurements performed together with each magnetic field measurement. Functional lumber spinal cord imaging is performed by using the spatial filter technique. We measure spinal cord evoked magnetic field from five healthy volunteers by applying 4-Hz electric stimuli at their peroneal nerve. Our proposed large field-of-view imaging shows clear nerve conduction in the lumber spine region for all five subjects, demonstrating its effectiveness. doi:10.1016/j.clinph.2013.02.107
P3-5. Altered motion perception in mild cognitive impairment and Alzheimer’s disease: An fMRI study—Takao Yamasaki, Hiroyuki Muranaka, Yumiko Kaseda, Yasuyo Mimori, Tsuyoshi Torii, Tomohiko Ohshita, Masayasu Matsumoto, Shozo Tobimatsu (Kyushu University, Fukuoka, Japan) Motion perceptual deficits are frequently observed in patients with mild cognitive impairment (MCI) and Alzheimer’s disease (AD). Information of coherent motion is mainly processed by the two distinct dorsal streams: the ventro-dorsal including inferior parietal lobule (IPL) and dorso-dorsal including superior parietal lobule (SPL) pathways. The former conveys radial optic flow (OF) information while the latter deals with horizontal (HO) motion information. To elucidate how the two dorsal streams are functionally altered, BOLD responses were measured during OF and HO perception in patients with MCI (n = 10) and mild AD (n = 8) and healthy elderly controls (n = 3) by using fMRI. In healthy elderly controls, OF predominantly increased the IPL signal whereas the SPL was more strongly activated by HO. In contrast, in both MCI and mild AD patients, there was a significant activation of the SPL by HO. However, no significant activation of the IPL was observed by OF. These findings indicate that the function of the ventro-dorsal (IPL) stream is selectively impaired in MCI and mild AD, while dorso-dorsal (SPL) function appears to be preserved. Therefore, we conclude that fMRI measurement of visual perception can be used as in vivo biomarkers for early functional brain changes in MCI and AD patients. doi:10.1016/j.clinph.2013.02.108
P3-7. Neurophysiological profile of acoustic startle response in Japanese children with autism spectrum disorders—Hidetoshi Takahashi, Takayuki Nakahachi, Aiko Moriwaki, Reiko Takei, Yukako Iida, Kazuo Ogino, Naoko Inada, Yoko Kamio (National Center Neurology Psychiatry, Tokyo, Japan) The acoustic startle response (ASR) is considered the promising neurophysiological measurements for translational research in psychiatry. A numbers of individuals with autism spectrum disorders (ASD) exhibit enhanced auditory perception; however, ASR to weak stimuli remains unclear. Here, we evaluated the basic profile of ASR with weak and strong stimuli in Japanese children with ASD. The subjects were 10 Japanese children with ASD and 34 with typical development (TD). The electromyographic activity of the left orbicularis oculi muscle to pulse stimuli of 65–110 dB SPL, in increments of 5 dB, was measured to evaluate ASR. The electroencephalogram (EEG) was also recorded during the testing. Quantitative autistic traits were assessed by Social Responsive Scale (SRS). Magnitude of ASR to weak stimuli (70 dB) was greater in ASD individuals, and was associated with SRS social awareness subscale scores. The peak startle latency was prolonged in ASD individuals, and was associated