- Email: [email protected]
NoGo task with different Chinese characters
Society Proceedings / Clinical Neurophysiology 120 (2009) e147–e180
stimulation of lumbosacral motor roots is a reliable method for measuring the CMAP size from lower limb muscles. doi:10.1016/j.clinph.2009.02.013
8. Magnetic stimulation of cauda equina in spinal canal with a flat large round coil—Hideyuki Matsumoto, Fitri Octaviana, Ritsuko Hanajima, Yasuo Terao, Masashi Hamada, Akihiro Yugeta, Satomi Inomata-Terada, Setsu Nakatani-Enomoto, Shoji Tsuji, Yoshikazu Ugawa (University of Tokyo, Tokyo, Japan) Magnetic round coil stimulation over the spinal enlargement activates the spinal nerves at the neuro-foramina level. However, the cauda equina in spinal canal has never been activated. The aim of this study is to activate the cauda equina using specially-devised round coil of diameter 20 cm named Magnetic Augmented Translumbosacral Stimulation coil (MATS coil). Total 40 healthy subjects were recruited. Magnetic stimulation was performed to obtain compound muscle action potentials (CMAPs) from abductor hallucis muscle placing the edge of coil over the L1 and L3 spinous processes. The CMAPs were compared with those elicited by high-voltage electrical stimulation. Cauda equina conduction time (CECT) between L1 and neuro-foramina levels was also measured. The CMAP latencies to L1 level MATS coil stimulation were identical to those evoked by electrical stimulation at the same level. The CMAP latencies to L3 level MATS coil stimulation were variable in each subject. L1 level MATS coil stimulation activates the cauda equina at the root exit site from conus medullaris. L3 level MATS coil stimulation activates some mid part of cauda equina or the distal cauda equina due to current spread. The MATS coil allows us to evaluate spinal nerve conduction in the cauda equina. doi:10.1016/j.clinph.2009.02.014
9. The suppression of the long-latency stretch reflex in the human tibialis anterior muscle by transcranial magnetic stimulation— Yoshihisa Masakado, Tetso Ota, Kanjiro Suzuki, Leon Abe, Hiroshi Fuseya, Akio Kimura, Meigen Liu (Keio University Tsukigase Rehabilitation Center, Izu and Tokyo, Japan) The purpose of this study was to investigate the transcortical nature of the long-latency stretch reflex (M3) n the human tibialis anterior muscle. This was achieved by applying a single pulse of subthreshold (90% motor threshold) transcortical magnetic stimulation (subTMS) at he site of the motor cortex. Such a stimulus is able to activate intracortical inhibitory circuits and thereby depress motor cortical output. We hypothesized that it could also suppress a transcortical reflex loop. The stretch reflex was elicited using a pedal attached to an electric motor. SubTMS was applied at several intervals prior to 3. Recordings were repeated 20–40 times. The reflex components were quantified using 20-ms windows in the averaged rectified electromyogram (EMG). SubTMS evoked significantly larger depression of M3 than of the background EMG in the same time frame when applied 5– 85 ms prior to M3 ðP < 0:05; n ¼ 10Þ. Furthermore, the effect on M3 was significantly larger than the effect on the spinal M2 ðP < 0:01; n ¼ 7Þ. Our results provide evidence hat the longlatency stretch reflex in the tibialis anterior muscle is at least partly transcortical. doi:10.1016/j.clinph.2009.02.015
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10. Somatosensory evoked potentials in multiple system atrophy—Hitoshi Mochizuki 1,2, Satoko Miyatake 2, Mikiya Suzuki 2, Katsuhisa Ogata 2, Mitsuru Kawai 2, Yoshikazu Ugawa 1 (1 Fukushima Medical University, Fukushima, Japan, 2 Higashi-Saitama National Hospital, Hasuda, Japan) Background: Some previous studies of somatosensory evoked potentials (SEP) in multiple system atrophy (MSA) were inconsistent. The aim of this study was to investigate whether the central sensory conduction time (CSCT) prolongation significantly correlated with the disease duration or subtype of MSA. Subjects and methods: Right median nerve SEPs were recorded in 21 patients with MSA (12 MSA-c and 9 MSA-p). The onset latencies and amplitudes of N9 (right Erb’s point -left shoulder), N11 (CV6-Fz), P13/14 (C30 – left shoulder) and N20 (C30 -Fz) were measured. Results: CSCT (inter-onset latencies between P13/14 and N20) had a significant positive correlation with disease duration (r = 0.628, P = 0.001; Pearson’s product–moment correlation), but not with subtype of MSA, age nor body height. No clinical factors had a significant correlation with the amplitude of any SEP components. Conclusion: In MSA patients, the CSCT prolongs in parallel with the disease duration. doi:10.1016/j.clinph.2009.02.016
11. Pediatric-onset rolandic seizure showing posteriorly-oriented rolandic spikes—Yosuke Kakisaka, Nobukazu Nakasato, Kazuhiro Haginoya, Akitake Kanno, Shigeru Tsuchiya (Department of Pediatrics, Tohoku University, Sendai, Japan) Benign childhood epilepsy with centro-temporal spikes (BECCT) is usually associated with anteriorly-oriented rolandic discharges. Here, we show an unusual type of childhood-onset epilepsy with sensorimotor seizures associated with posteriorly-oriented rolandic discharges. We identified 3 patients with sensorimotor seizures aged under 13 years at onset, with no abnormal magnetic resonance imaging findings, and posteriorly-oriented rolandic discharges detected by MEG. Ictal and interictal symptoms were evaluated retrospectively. All patients had rolandic seizures as well as atypical seizures, such as falling, auditory hallucinations or automatism. Seizures were medically intractable in all cases. Posteriorly-oriented rolandic discharges are better detected by MEG, and may exclude BECCT. doi:10.1016/j.clinph.2009.02.017
12. The ERP findings during a Go/NoGo task with different Chinese characters—Sayaka Noguchi, Yoshimi Kaga, Tomoko Tando, Kanji Sugita, Masao Aihara (University of Yamanashi, Yamanashi, Japan) In souse localization studies, NoGo-N2 component with a Go/ NoGo tasks originated from the anterior cingulate cortex and the amplitude increased in conflict condition. NoGo-P3 component was enhanced by the response inhibition and the source located in the orbitofrontal cortex. In order to investigate the change of event-related potentials (ERPs) during a Go/NoGo task with different Chinese characters, 10 normal adults performed a Continuous Performing Test using five Chinese characters. Subjects responded to a
e150
Society Proceedings / Clinical Neurophysiology 120 (2009) e147–e180
Go stimulus after a cue stimulus presented on the monitor and ignored the other three stimuli. The one of the three NoGo stimuli is visually most similar to the Go stimulus (similar condition), and another is most distinct from it (distinct condition). We obtained ERPs of the Go and NoGo conditions from 13-channel EEG recordings and measured peak latency, amplitude, and topographic distribution of the NoGo-N2 and NoGo-P3 components. Commission error was highest for the NoGo stimulus of the similar condition. The amplitude of NoGo-P3 was largest and the latency shortest in the distinct condition. The amplitude of NoGo-N2 was highest and distributed in relatively anterior regions in the similar condition. These results suggested that the conflict condition with visual difficulty of tasks may activate anterior cingulate cortex and prefrontal cortex. doi:10.1016/j.clinph.2009.02.018
13. Utility of functional MRI using calculation task in neurosurgery—Takahiro Ota, Kyousuke Kamada, Shigeki Aoki, Nobuhito Saito (University of Tokyo, Tokyo, Japan) Background and purpose: We used functional MRI to visualize calculation centers in the parietal lobe, and demonstrated a correlation between sequential changes of fMRI results and calculation ability after neurological surgery. Methods: Fifteen subjects were studied, including 5 normal controls and 10 patients with brain lesions. The calculation task was to simply add three numbers projected onto a screen (addition task) and to multiply two one-digit numbers (multiplication task). Results: Functional MRI showed active pixels in bilateral interparietal sulcus (especially in dominant hemisphere) in all subjects. Mean values and standard deviation of left/right ratios of active pixels in the interparietal sulcus in neurosurgical patients were almost the same in normal controls. Conclusions: Functional MRI is a useful technique for noninvasive preoperative mapping of calculation centers. In the two patients with parietal lesions, postoperative functional MRI well reflected their calculation ability. We should preserve the interparietal sulcus in the dominant hemisphere to maintain calculation ability. doi:10.1016/j.clinph.2009.02.019
14. Efficacy and limitation of the conventional neonatal EEG for extremely low birth weight infants—Tetsuo Kubota, Hiroyuki Kidokoro, Tetsuo Hattori (Anjo Kosei Hospital, Anjo, Japan) It is well known that neonatal EEG is a powerful tool for the diagnosis and the assessment of prognosis of brain injuries in the preterm infant. According to the abnormal EEG patterns, we could predict the future cerebral palsy or mental retardation in these patients. The recent increase in the survival rate of very preterm infants has resulted in an increasing incidence of neurological sequelae. The sequelae are not only motor but also various cognitive disorders. We focused on the extremely low birth weight infants (ELBWI) and compared predictive values with term equivalent MRI and sequential EEG study in the NICU. As well as previous reports, we found that the term equivalent MRI could predict the later motor and cognitive disorders. In the EEG study, though we also predicted their neurological sequlae, the predictive values of neurological sequelae were less than those of MRI. We considered that these causes were the difficulties of detection with abnormal EEG findings
in ELBWI and restriction of the very early recording for their weak skins. In the future, we will have to examine the EEG findings more carefully and find the new characteristic and predictable EEG activities for later functional disorders of ELBWI. doi:10.1016/j.clinph.2009.02.020
15. Learning about advantageous decision-making influences subsequent sleep—Takashi Abe, Yoko Komada, Yuichi Inoue, Tadao Hori (Hiroshima University, Higashi-Hiroshima, Japan) This study was aimed to investigate the relationship between learning of advantageous decision-making and subsequent sleep. Eight healthy volunteers participated in this study (two men and six women, 20–24 years old, mean 21.9 years), and all of them assigned to both learning and control conditions. Polysomnograms were recorded after modified version of Iowa Gambling Task (Bechara et al., 1994) in learning condition and after control task in control condition. The control task was the task which did not need to learn the advantageous choice since the profile of all the choices was same. As a result of comparing the sleep variables of the learning condition and control condition, rapid eye movements (REM) density in learning condition was significantly greater than control condition. Moreover, increased REM density from control condition to learning condition predicted post-sleep increment of the number of choices from advantageous decision-making. This result suggests that offline memory reprocessing about the learning of advantageous decision-making occurs in relation to rapid eye movements in REM sleep. doi:10.1016/j.clinph.2009.02.021
16. Electrical activities during abnormal muscle contractions in a patient with rippling muscle disease—Takakuni Maki, Riki Matsumoto, Takayuki Kondo, Insuk Son, Takahiro Mezaki, Ichizo Nishino, Akio Ikeda, Nobuo Kohara, Ryosuke Takahashi (Kyoto University, Kyoto, Japan) Objective: To determine the electrophysiological trait of rippling muscle disease (RMD). Background: RMD is a myopathy with symptoms and signs of muscular hyperirritability characterized by percussion-induced rapid muscle contractions (PIRCs) and involuntary rolling muscle contractions (muscle rippling) provoked by mechanical stimuli and stretch. Most reports have shown that these abnormal muscle contractions were electrically silent, i.e., no action potentials in electromyogram. However, a few studies were against the notion, and the pathophysiology needs to be clarified by detail electrophysiological investigation. Methods: Subject is a 30-year-old man with RMD diagnosed by a reduced expression of caveolin-3 in the sarcolemma and missense mutation Arg27Gln in a caveolin-3 gene. Abnormal muscle contractions were investigated simultaneously with electromyogram and ultrasound. Results: During muscle rippling of the quadriceps femoris, the ultrasound study revealed rolling muscle contractions not only in superficial parts but also in deep parts. Needle electromyogram of the muscle rippling and PIRCs revealed electrical activities with short duration (<2 ms). The activities were not well recorded with surface electromyogram. This most likely represented single-fiber potentials rather than motor-unit potentials.
stimulation of lumbosacral motor roots is a reliable method for measuring the CMAP size from lower limb muscles. doi:10.1016/j.clinph.2009.02.013
8. Magnetic stimulation of cauda equina in spinal canal with a flat large round coil—Hideyuki Matsumoto, Fitri Octaviana, Ritsuko Hanajima, Yasuo Terao, Masashi Hamada, Akihiro Yugeta, Satomi Inomata-Terada, Setsu Nakatani-Enomoto, Shoji Tsuji, Yoshikazu Ugawa (University of Tokyo, Tokyo, Japan) Magnetic round coil stimulation over the spinal enlargement activates the spinal nerves at the neuro-foramina level. However, the cauda equina in spinal canal has never been activated. The aim of this study is to activate the cauda equina using specially-devised round coil of diameter 20 cm named Magnetic Augmented Translumbosacral Stimulation coil (MATS coil). Total 40 healthy subjects were recruited. Magnetic stimulation was performed to obtain compound muscle action potentials (CMAPs) from abductor hallucis muscle placing the edge of coil over the L1 and L3 spinous processes. The CMAPs were compared with those elicited by high-voltage electrical stimulation. Cauda equina conduction time (CECT) between L1 and neuro-foramina levels was also measured. The CMAP latencies to L1 level MATS coil stimulation were identical to those evoked by electrical stimulation at the same level. The CMAP latencies to L3 level MATS coil stimulation were variable in each subject. L1 level MATS coil stimulation activates the cauda equina at the root exit site from conus medullaris. L3 level MATS coil stimulation activates some mid part of cauda equina or the distal cauda equina due to current spread. The MATS coil allows us to evaluate spinal nerve conduction in the cauda equina. doi:10.1016/j.clinph.2009.02.014
9. The suppression of the long-latency stretch reflex in the human tibialis anterior muscle by transcranial magnetic stimulation— Yoshihisa Masakado, Tetso Ota, Kanjiro Suzuki, Leon Abe, Hiroshi Fuseya, Akio Kimura, Meigen Liu (Keio University Tsukigase Rehabilitation Center, Izu and Tokyo, Japan) The purpose of this study was to investigate the transcortical nature of the long-latency stretch reflex (M3) n the human tibialis anterior muscle. This was achieved by applying a single pulse of subthreshold (90% motor threshold) transcortical magnetic stimulation (subTMS) at he site of the motor cortex. Such a stimulus is able to activate intracortical inhibitory circuits and thereby depress motor cortical output. We hypothesized that it could also suppress a transcortical reflex loop. The stretch reflex was elicited using a pedal attached to an electric motor. SubTMS was applied at several intervals prior to 3. Recordings were repeated 20–40 times. The reflex components were quantified using 20-ms windows in the averaged rectified electromyogram (EMG). SubTMS evoked significantly larger depression of M3 than of the background EMG in the same time frame when applied 5– 85 ms prior to M3 ðP < 0:05; n ¼ 10Þ. Furthermore, the effect on M3 was significantly larger than the effect on the spinal M2 ðP < 0:01; n ¼ 7Þ. Our results provide evidence hat the longlatency stretch reflex in the tibialis anterior muscle is at least partly transcortical. doi:10.1016/j.clinph.2009.02.015
e149
10. Somatosensory evoked potentials in multiple system atrophy—Hitoshi Mochizuki 1,2, Satoko Miyatake 2, Mikiya Suzuki 2, Katsuhisa Ogata 2, Mitsuru Kawai 2, Yoshikazu Ugawa 1 (1 Fukushima Medical University, Fukushima, Japan, 2 Higashi-Saitama National Hospital, Hasuda, Japan) Background: Some previous studies of somatosensory evoked potentials (SEP) in multiple system atrophy (MSA) were inconsistent. The aim of this study was to investigate whether the central sensory conduction time (CSCT) prolongation significantly correlated with the disease duration or subtype of MSA. Subjects and methods: Right median nerve SEPs were recorded in 21 patients with MSA (12 MSA-c and 9 MSA-p). The onset latencies and amplitudes of N9 (right Erb’s point -left shoulder), N11 (CV6-Fz), P13/14 (C30 – left shoulder) and N20 (C30 -Fz) were measured. Results: CSCT (inter-onset latencies between P13/14 and N20) had a significant positive correlation with disease duration (r = 0.628, P = 0.001; Pearson’s product–moment correlation), but not with subtype of MSA, age nor body height. No clinical factors had a significant correlation with the amplitude of any SEP components. Conclusion: In MSA patients, the CSCT prolongs in parallel with the disease duration. doi:10.1016/j.clinph.2009.02.016
11. Pediatric-onset rolandic seizure showing posteriorly-oriented rolandic spikes—Yosuke Kakisaka, Nobukazu Nakasato, Kazuhiro Haginoya, Akitake Kanno, Shigeru Tsuchiya (Department of Pediatrics, Tohoku University, Sendai, Japan) Benign childhood epilepsy with centro-temporal spikes (BECCT) is usually associated with anteriorly-oriented rolandic discharges. Here, we show an unusual type of childhood-onset epilepsy with sensorimotor seizures associated with posteriorly-oriented rolandic discharges. We identified 3 patients with sensorimotor seizures aged under 13 years at onset, with no abnormal magnetic resonance imaging findings, and posteriorly-oriented rolandic discharges detected by MEG. Ictal and interictal symptoms were evaluated retrospectively. All patients had rolandic seizures as well as atypical seizures, such as falling, auditory hallucinations or automatism. Seizures were medically intractable in all cases. Posteriorly-oriented rolandic discharges are better detected by MEG, and may exclude BECCT. doi:10.1016/j.clinph.2009.02.017
12. The ERP findings during a Go/NoGo task with different Chinese characters—Sayaka Noguchi, Yoshimi Kaga, Tomoko Tando, Kanji Sugita, Masao Aihara (University of Yamanashi, Yamanashi, Japan) In souse localization studies, NoGo-N2 component with a Go/ NoGo tasks originated from the anterior cingulate cortex and the amplitude increased in conflict condition. NoGo-P3 component was enhanced by the response inhibition and the source located in the orbitofrontal cortex. In order to investigate the change of event-related potentials (ERPs) during a Go/NoGo task with different Chinese characters, 10 normal adults performed a Continuous Performing Test using five Chinese characters. Subjects responded to a
e150
Society Proceedings / Clinical Neurophysiology 120 (2009) e147–e180
Go stimulus after a cue stimulus presented on the monitor and ignored the other three stimuli. The one of the three NoGo stimuli is visually most similar to the Go stimulus (similar condition), and another is most distinct from it (distinct condition). We obtained ERPs of the Go and NoGo conditions from 13-channel EEG recordings and measured peak latency, amplitude, and topographic distribution of the NoGo-N2 and NoGo-P3 components. Commission error was highest for the NoGo stimulus of the similar condition. The amplitude of NoGo-P3 was largest and the latency shortest in the distinct condition. The amplitude of NoGo-N2 was highest and distributed in relatively anterior regions in the similar condition. These results suggested that the conflict condition with visual difficulty of tasks may activate anterior cingulate cortex and prefrontal cortex. doi:10.1016/j.clinph.2009.02.018
13. Utility of functional MRI using calculation task in neurosurgery—Takahiro Ota, Kyousuke Kamada, Shigeki Aoki, Nobuhito Saito (University of Tokyo, Tokyo, Japan) Background and purpose: We used functional MRI to visualize calculation centers in the parietal lobe, and demonstrated a correlation between sequential changes of fMRI results and calculation ability after neurological surgery. Methods: Fifteen subjects were studied, including 5 normal controls and 10 patients with brain lesions. The calculation task was to simply add three numbers projected onto a screen (addition task) and to multiply two one-digit numbers (multiplication task). Results: Functional MRI showed active pixels in bilateral interparietal sulcus (especially in dominant hemisphere) in all subjects. Mean values and standard deviation of left/right ratios of active pixels in the interparietal sulcus in neurosurgical patients were almost the same in normal controls. Conclusions: Functional MRI is a useful technique for noninvasive preoperative mapping of calculation centers. In the two patients with parietal lesions, postoperative functional MRI well reflected their calculation ability. We should preserve the interparietal sulcus in the dominant hemisphere to maintain calculation ability. doi:10.1016/j.clinph.2009.02.019
14. Efficacy and limitation of the conventional neonatal EEG for extremely low birth weight infants—Tetsuo Kubota, Hiroyuki Kidokoro, Tetsuo Hattori (Anjo Kosei Hospital, Anjo, Japan) It is well known that neonatal EEG is a powerful tool for the diagnosis and the assessment of prognosis of brain injuries in the preterm infant. According to the abnormal EEG patterns, we could predict the future cerebral palsy or mental retardation in these patients. The recent increase in the survival rate of very preterm infants has resulted in an increasing incidence of neurological sequelae. The sequelae are not only motor but also various cognitive disorders. We focused on the extremely low birth weight infants (ELBWI) and compared predictive values with term equivalent MRI and sequential EEG study in the NICU. As well as previous reports, we found that the term equivalent MRI could predict the later motor and cognitive disorders. In the EEG study, though we also predicted their neurological sequlae, the predictive values of neurological sequelae were less than those of MRI. We considered that these causes were the difficulties of detection with abnormal EEG findings
in ELBWI and restriction of the very early recording for their weak skins. In the future, we will have to examine the EEG findings more carefully and find the new characteristic and predictable EEG activities for later functional disorders of ELBWI. doi:10.1016/j.clinph.2009.02.020
15. Learning about advantageous decision-making influences subsequent sleep—Takashi Abe, Yoko Komada, Yuichi Inoue, Tadao Hori (Hiroshima University, Higashi-Hiroshima, Japan) This study was aimed to investigate the relationship between learning of advantageous decision-making and subsequent sleep. Eight healthy volunteers participated in this study (two men and six women, 20–24 years old, mean 21.9 years), and all of them assigned to both learning and control conditions. Polysomnograms were recorded after modified version of Iowa Gambling Task (Bechara et al., 1994) in learning condition and after control task in control condition. The control task was the task which did not need to learn the advantageous choice since the profile of all the choices was same. As a result of comparing the sleep variables of the learning condition and control condition, rapid eye movements (REM) density in learning condition was significantly greater than control condition. Moreover, increased REM density from control condition to learning condition predicted post-sleep increment of the number of choices from advantageous decision-making. This result suggests that offline memory reprocessing about the learning of advantageous decision-making occurs in relation to rapid eye movements in REM sleep. doi:10.1016/j.clinph.2009.02.021
16. Electrical activities during abnormal muscle contractions in a patient with rippling muscle disease—Takakuni Maki, Riki Matsumoto, Takayuki Kondo, Insuk Son, Takahiro Mezaki, Ichizo Nishino, Akio Ikeda, Nobuo Kohara, Ryosuke Takahashi (Kyoto University, Kyoto, Japan) Objective: To determine the electrophysiological trait of rippling muscle disease (RMD). Background: RMD is a myopathy with symptoms and signs of muscular hyperirritability characterized by percussion-induced rapid muscle contractions (PIRCs) and involuntary rolling muscle contractions (muscle rippling) provoked by mechanical stimuli and stretch. Most reports have shown that these abnormal muscle contractions were electrically silent, i.e., no action potentials in electromyogram. However, a few studies were against the notion, and the pathophysiology needs to be clarified by detail electrophysiological investigation. Methods: Subject is a 30-year-old man with RMD diagnosed by a reduced expression of caveolin-3 in the sarcolemma and missense mutation Arg27Gln in a caveolin-3 gene. Abnormal muscle contractions were investigated simultaneously with electromyogram and ultrasound. Results: During muscle rippling of the quadriceps femoris, the ultrasound study revealed rolling muscle contractions not only in superficial parts but also in deep parts. Needle electromyogram of the muscle rippling and PIRCs revealed electrical activities with short duration (<2 ms). The activities were not well recorded with surface electromyogram. This most likely represented single-fiber potentials rather than motor-unit potentials.