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P1-51. Electrophysiological findings in patients with neuromyelitis optica
Society Proceedings / Clinical Neurophysiology 124 (2013) e19–e38
P1-37. Distal compound muscle action potential dispersion would commonly occur in patients with anti-MAG/SGPG antibody associated neuropathy—Takahiro Shimizu, Ritsuko Hanajima, Ryosuke Tsutsumi, Nobuyuki Tanaka, Yuichiro Shirota, Shinya Ohminami, Shunichi Matsuda, Shoji Tsuji, Yoshikazu Ugawa, Yasuo Terao (University of Tokyo, Tokyo, Japan) The prolonged distal compound muscle action potential (CMAP) duration (i.e. distal temporal dispersion) has been recently validated as a measure of distal demyelination in chronic inflammatory demyelinating polyneuropathy (CIDP) patients. In previous reports, distal temporal dispersion was rare in patients with anti-MAG/SGPG antibody associated neuropathy. Here, to test this notion, we studied distal CMAP duration in our patients. Subjects were 5 patients with anti-MAG and/or anti-SGPG antibody associated neuropathy. We performed conventional motor conduction studies in unilateral median, ulnar and tibial nerves. The cutoff point of distal temporal dispersion was set at 9ms based on a previous report. Distal CMAP duration was prolonged in 4 of 5 patients. Among 13 responses, 50% (median), 60% (ulnar) and 75% (tibial) presented distal temporal dispersion. There were negative correlation between distal CMAP duration and conduction velocity (R[2] = 0.63, p = 0.0012), and positive correlation between distal CMAP duration and distal latency (R[2] = 0.75, p = 0.0001). Our findings suggest that distal temporal dispersion is not rare in patients with anti-MAG/SGPG antibody associated neuropathy, which is in contrast to previous reports. doi:10.1016/j.clinph.2013.02.096
P1-51. Electrophysiological findings in patients with neuromyelitis optica—Keiko Ohnari, Motonobu Nishio, Kazumasa Okada, Takenori Uozumi, Sadatoshi Tsuji (Occupational and Environmental Health Medical University, Fukuoka, Japan) The aim of this study was to report the electrophysiological findings in patients with neuromyelitis optica (NMO) differentiated from multiple sclerosis (MS). We diagnosed 17 patients with NMO based on the clinical symptoms, brain MRI, and aquaporin-4 antibody positivity. Those patients underwent visual evoked potential (VEP), auditory brainstem response (ABR), somatosensory evoked potential (SEP), and motor evoked potential (MEP) analyses. Forty-four point one percent of the patients presented abnormal VEP findings. All patients presented normal ABR findings. Abnomal findings were presented at rates of 8.8% in upper extremity SEP, 21.9% in lower extremity SEP, 13.6% in upper extremity MEP, and 36.4% in lower extremity. There were few abnormal subclinical findings in the electrophysiological findings. We found smaller percentage of abnormal findings in patients with NMO compared to patients with MS. doi:10.1016/j.clinph.2013.02.097
P1-55. Late positive potentials associated with the attractiveness of the appearances of commercial goods—Hiroshi Nittono (Hiroshima University, Higashi-Hiroshima, Japan) Commercial goods with attractive appearances capture consumers’ attention and interest. In order to find an objective measure that could supplement subjective ratings of impressions, this study examined how event-related brain potentials (ERPs) correlated with the attractive appearances of objects. Eighteen university students viewed 150 color photographs of everyday objects, such as toys and tools, for a stimulus duration of 1500 ms. After viewing each
e35
stimulus, the participants rated its attractiveness using a visual analog scale. Electroencephalograms were recorded at 38 scalp sites. Based on each participant’s ratings, the 150 pictures were sorted into three categories: high, middle, and low attractiveness. ERPs were computed by averaging the epoch starting 200 ms before and ending 1500 ms after stimulus onset. A temporal principal component analysis revealed that stimuli with higher attractiveness ratings elicited a larger late positive potential (LPP) that was dominant at frontocentral scalp sites in the latency range of 500–1500 ms. Previous studies have shown that the LPP is related to sustained attentional processing of affective stimuli. This study suggests that, combined with subjective ratings, the LPP can be used as an objective measure of the attractiveness of the appearances of visual objects. doi:10.1016/j.clinph.2013.02.098
P1-67. N170 response to change in facial expressions is correlated with autistic traits: An event-related potential study—Motonobu Hidaka, Takashi Morotomi, Harumitsu Murohashi (Hokkaido University, Hokkaido, Japan) Face-specific N170 for facial expressions is smaller in autism spectrum disorder (ASD). The aim of this study was to investigate the processing of dynamic facial expressions in ASD. Facial expressions preceded by neutral face elicited a larger N170 (Miyoshi et al., 2004). This study quantified autistic traits in 17 healthy individuals, using the Autism-Spectrum Quotient (AQ, Baron-Cohen et al., 2001). N170 amplitude for facial expressional change was correlated with autistic traits (r = 0.49, P < 0.05). Moreover, we divided participants into high and low AQ groups. Participants with high AQ had more smaller N170 for anger expression than participants with low AQ (P = 0.08). However There was no difference of N170 for happy expression between two groups. Our findings suggest the individuals with the autistic traits have an abnormally encoding for negative dynamic facial expression. doi:10.1016/j.clinph.2013.02.099
P1-69. Magnetoencephalography revealed functional impairment in left frontal and temporal lobule in child with severe reading difficulty: Case report—Kazuyori Yagyu, Atsushi Shimojo, Satomi Yokoyama, Michiru Iwata, Makiko Ohtsuka, Atsuhito Toyomaki, Hideaki Shiraishi, Harumitsu Murohashi (Nirenokai kodomoclinic, Hokkaido University, Sapporo, Japan) Case: The case was 4th grade boy who was born without abnormal birth history. His spasticity appeared in his infancy. From one to two years old, seizures with impairment of consciousness were found. EEG revealed left frontal spikes. Later, seizure disappeared spontaneously without medication. In comparison with typical children with same school age as him, he had severe difficulty with reading and writing. His score of full-IQ, verbal-IQ and Performance-IQ were 63, 62 and 71 respectively with WISC-III. Reading assessment test showed over +20SD reading time in all tasks. Methods: His brain functional assessment was executed. He was told to read aloud 2–5 mora words and name pictures. While reading, magnetoencephalography (MEG) data were recorded using a 204-channel, whole-head gradiometer. In 107 trials of each task, words and picture presentation times were 6 s and inter-stimulus intervals were 1 s. MEG data were averaged by each task and analyzed with dynamic statistical parametric mapping (dSPM). Results: In all three tasks, averaged data and dSPM revealed obvious decrease of activities at left temporal and frontal lobule compared to right 200–400 ms after from word/picture presentation.
P1-37. Distal compound muscle action potential dispersion would commonly occur in patients with anti-MAG/SGPG antibody associated neuropathy—Takahiro Shimizu, Ritsuko Hanajima, Ryosuke Tsutsumi, Nobuyuki Tanaka, Yuichiro Shirota, Shinya Ohminami, Shunichi Matsuda, Shoji Tsuji, Yoshikazu Ugawa, Yasuo Terao (University of Tokyo, Tokyo, Japan) The prolonged distal compound muscle action potential (CMAP) duration (i.e. distal temporal dispersion) has been recently validated as a measure of distal demyelination in chronic inflammatory demyelinating polyneuropathy (CIDP) patients. In previous reports, distal temporal dispersion was rare in patients with anti-MAG/SGPG antibody associated neuropathy. Here, to test this notion, we studied distal CMAP duration in our patients. Subjects were 5 patients with anti-MAG and/or anti-SGPG antibody associated neuropathy. We performed conventional motor conduction studies in unilateral median, ulnar and tibial nerves. The cutoff point of distal temporal dispersion was set at 9ms based on a previous report. Distal CMAP duration was prolonged in 4 of 5 patients. Among 13 responses, 50% (median), 60% (ulnar) and 75% (tibial) presented distal temporal dispersion. There were negative correlation between distal CMAP duration and conduction velocity (R[2] = 0.63, p = 0.0012), and positive correlation between distal CMAP duration and distal latency (R[2] = 0.75, p = 0.0001). Our findings suggest that distal temporal dispersion is not rare in patients with anti-MAG/SGPG antibody associated neuropathy, which is in contrast to previous reports. doi:10.1016/j.clinph.2013.02.096
P1-51. Electrophysiological findings in patients with neuromyelitis optica—Keiko Ohnari, Motonobu Nishio, Kazumasa Okada, Takenori Uozumi, Sadatoshi Tsuji (Occupational and Environmental Health Medical University, Fukuoka, Japan) The aim of this study was to report the electrophysiological findings in patients with neuromyelitis optica (NMO) differentiated from multiple sclerosis (MS). We diagnosed 17 patients with NMO based on the clinical symptoms, brain MRI, and aquaporin-4 antibody positivity. Those patients underwent visual evoked potential (VEP), auditory brainstem response (ABR), somatosensory evoked potential (SEP), and motor evoked potential (MEP) analyses. Forty-four point one percent of the patients presented abnormal VEP findings. All patients presented normal ABR findings. Abnomal findings were presented at rates of 8.8% in upper extremity SEP, 21.9% in lower extremity SEP, 13.6% in upper extremity MEP, and 36.4% in lower extremity. There were few abnormal subclinical findings in the electrophysiological findings. We found smaller percentage of abnormal findings in patients with NMO compared to patients with MS. doi:10.1016/j.clinph.2013.02.097
P1-55. Late positive potentials associated with the attractiveness of the appearances of commercial goods—Hiroshi Nittono (Hiroshima University, Higashi-Hiroshima, Japan) Commercial goods with attractive appearances capture consumers’ attention and interest. In order to find an objective measure that could supplement subjective ratings of impressions, this study examined how event-related brain potentials (ERPs) correlated with the attractive appearances of objects. Eighteen university students viewed 150 color photographs of everyday objects, such as toys and tools, for a stimulus duration of 1500 ms. After viewing each
e35
stimulus, the participants rated its attractiveness using a visual analog scale. Electroencephalograms were recorded at 38 scalp sites. Based on each participant’s ratings, the 150 pictures were sorted into three categories: high, middle, and low attractiveness. ERPs were computed by averaging the epoch starting 200 ms before and ending 1500 ms after stimulus onset. A temporal principal component analysis revealed that stimuli with higher attractiveness ratings elicited a larger late positive potential (LPP) that was dominant at frontocentral scalp sites in the latency range of 500–1500 ms. Previous studies have shown that the LPP is related to sustained attentional processing of affective stimuli. This study suggests that, combined with subjective ratings, the LPP can be used as an objective measure of the attractiveness of the appearances of visual objects. doi:10.1016/j.clinph.2013.02.098
P1-67. N170 response to change in facial expressions is correlated with autistic traits: An event-related potential study—Motonobu Hidaka, Takashi Morotomi, Harumitsu Murohashi (Hokkaido University, Hokkaido, Japan) Face-specific N170 for facial expressions is smaller in autism spectrum disorder (ASD). The aim of this study was to investigate the processing of dynamic facial expressions in ASD. Facial expressions preceded by neutral face elicited a larger N170 (Miyoshi et al., 2004). This study quantified autistic traits in 17 healthy individuals, using the Autism-Spectrum Quotient (AQ, Baron-Cohen et al., 2001). N170 amplitude for facial expressional change was correlated with autistic traits (r = 0.49, P < 0.05). Moreover, we divided participants into high and low AQ groups. Participants with high AQ had more smaller N170 for anger expression than participants with low AQ (P = 0.08). However There was no difference of N170 for happy expression between two groups. Our findings suggest the individuals with the autistic traits have an abnormally encoding for negative dynamic facial expression. doi:10.1016/j.clinph.2013.02.099
P1-69. Magnetoencephalography revealed functional impairment in left frontal and temporal lobule in child with severe reading difficulty: Case report—Kazuyori Yagyu, Atsushi Shimojo, Satomi Yokoyama, Michiru Iwata, Makiko Ohtsuka, Atsuhito Toyomaki, Hideaki Shiraishi, Harumitsu Murohashi (Nirenokai kodomoclinic, Hokkaido University, Sapporo, Japan) Case: The case was 4th grade boy who was born without abnormal birth history. His spasticity appeared in his infancy. From one to two years old, seizures with impairment of consciousness were found. EEG revealed left frontal spikes. Later, seizure disappeared spontaneously without medication. In comparison with typical children with same school age as him, he had severe difficulty with reading and writing. His score of full-IQ, verbal-IQ and Performance-IQ were 63, 62 and 71 respectively with WISC-III. Reading assessment test showed over +20SD reading time in all tasks. Methods: His brain functional assessment was executed. He was told to read aloud 2–5 mora words and name pictures. While reading, magnetoencephalography (MEG) data were recorded using a 204-channel, whole-head gradiometer. In 107 trials of each task, words and picture presentation times were 6 s and inter-stimulus intervals were 1 s. MEG data were averaged by each task and analyzed with dynamic statistical parametric mapping (dSPM). Results: In all three tasks, averaged data and dSPM revealed obvious decrease of activities at left temporal and frontal lobule compared to right 200–400 ms after from word/picture presentation.