- Email: [email protected]
PO3.14 Effects of Corollary Discharge on Auditory N1 Component of Event-Related Potentials in Healthy Subjects
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Posters: PO3. Evoked Potentials
radices, indirectly reflecting the functional condition of a horse tail and a spinal cord cone. However, other tendency in increase indicators latency N22 has been revealed also. The more there was an increase of latency N22, the treatment of a painful syndrome and restoration at compressing radix was stretched on long time. Conclusions: Thus, research SSEP at intervertebral disk’s hernias on lumbo-sacral osteochondrosis reveals changes in an increase kind latency N22, testifying about compressing a radix, and also can serve as criterion of expressiveness of a compression and duration of spent therapy.
poststimulus. Amplitudes were measured with respect to an average voltage during the 50 ms prestimulus. Results: The amplitude of N1 components were lower during vocalizing than during the silent baseline condition. Conclusions: These results may replicate that the auditory N1 component may reflect the effects of corollary discharge.
PO3.13 Correlation between Intracranial Pressure and Visual Evoked Potential Findings in Children with Craniosynostosis
Akira Iwanami *, Yuka Okajima, Nobumasa Kato Dept. of Psychiatry, Showa University School of Medicine, Japan E-mail address: [email protected]
In Soo Joo *, Seung-Hyeon Yeo, Wen-Yu Li Dept. of Neurology, Ajou University School of Medicine, Korea E-mail address: [email protected]
Background: Corollary discharge is a brain electrical activity associated with self-monitoring, which distinguishes self from others in thoughts or behaviors. Using event-related potential (ERP) recordings in humans, it is possible to assess corollary discharge non-invasively. Several previous studies have revealed that the amplitude of the N1 component elicited during an auditory task is reduced while a subject is vocalizing, which may index the effect of corollary discharge on auditory ERPs. In this study, we attempted to assess the effect of vocalizing on the N1 component using a topographical analysis. Methods: Subjects were 15 healthy volunteers. Event-related potentials were recorded during a passive auditory task while subjects were silent, while subjects were vocalizing, and while subjects listened to the vocalizing. Subjects were presented with a series of 500 auditory stimuli with a fixed interstimulus interval of 500 ms. In the task, 90% of the stimuli were tones of 1 KHz, and the other 10% tones of 2 KHz. According to the international 10 20 system, the scalp electroencephalogram (EEG) was recorded at Fp1, Fp2, F3, F4, C3, C4, P3, P4, O1, O2, F7, F8, T3, T4, T5, T6, Fz, Cz, and Pz monopolarly. Vertical and horizontal electrooculograms (EOG) were recorded from electrodes placed below and at the outer canthus of the right eye. EEG samples were acquired every 1 ms from 50 ms before to 450 ms after the stimulus onset. The responses to frequent and rare tones and were averaged separately. N1 was defined as the most negative peak between 60 and 160 ms poststimulus. Amplitudes were measured with respect to an average voltage during the 50 ms prestimulus. Results: The distribution of the N1 component differed among the three conditions. Conclusions: These results suggested that corollary discharge may have different effects among the subcomponents of the auditory N1.
Background: Craniosynostosis, the premature closure of one or more cranial sutures, can cause elevated intracranial pressure (ICP) and optic nerve damage. Visually evoked potentials (VEP) are commonly used for assessing the anterior and posterior visual pathways. We evaluated the correlation between ICP and VEP findings in children with craniosynostosis. Methods: From January 2008 until December 2008, 29 children (13 males and 19 females) with craniosynostosis were elicited by flashing light using light emitting diode goggles in our neurophysiological laboratory. Every child underwent ophthalmological examination for exclusion of ocular or optic nerve problems not related with elevated ICP. Lumbar puncture was performed in order to measure ICP. Results: In 29 children (mean age 2.6 years, range from 1 to 8 years) VEP and ICP were obtained preoperatively. Of them, 13 (44.8%) children showed absent or delayed N75 bilaterally on VEP except one. Mean ICP of all patients measured via lumbar puncture was 26.4±7.7 cmH2 O (range 14 to 42.5 cmH2 O). There was no significant difference in the mean ICP values between patients showing abnormal (13 patients, 26.4±7.9 cmH2 O) and normal VEP findings (16 patients, 26.4±7.8 cmH2 O). And the age of patient was also not significantly different between two groups (p = 0.44). Conclusions: Quite a few craniosynostosis patients showed abnormal patterns on VEP and, therefore, VEP could be a useful diagnostic tool for early detection of visual compromises in these patients. But the results suggest that abnormal VEP patterns do not always reflect an elevated ICP and could not be an absolute but helpful criterion to make a decision for the need of surgical treatment in children with craniosynostosis. PO3.14 Effects of Corollary Discharge on Auditory N1 Component of Event-Related Potentials in Healthy Subjects Akira Iwanami *, Yuka Okajima, Nobumasa Kato Dept. of Psychiatry, Showa University School of Medicine, Japan E-mail address: [email protected] Background: Corollary discharge is a brain electrical activity associated with self-monitoring, which distinguishes self from others in thoughts or behaviors. Corollary discharge can be non-invasively assessed using eventrelated potential (ERP) recordings in humans. Several previous studies have revealed that the amplitude of the N1 component elicited during an “odd-ball” task is reduced while a healthy subject is vocalizing, which may index the effect of corollary discharge on auditory ERPs. In this study, we attempted to assess the effect of vocalizing on the N1 component during a passive oddball task in healthy adults. Methods: Event-related potentials were recorded during a passive auditory task while subjects were silent, while subjects were vocalizing, and while subjects listened to the vocalizing. Subjects were presented with a series of 500 auditory stimuli with a fixed interstimulus interval of 500 ms. In the task, 90% of the stimuli were tones of 1 KHz, and the other 10% tones of 2 KHz. The stimulus intensity was 75 dBSPL, and the tone duration 50 ms, with a rise/fall time of 10 ms. According to the international 10 20 system, the scalp electroencephalogram (EEG) was recorded. The bandpass was set at 0.15 120 Hz. Vertical and horizontal electrooculograms (EOG) were recorded from electrodes placed below and at the outer canthus of the right eye. EEG samples were acquired every 1 ms from 50 ms before to 450 ms after the stimulus onset. The responses to frequent and rare tones and were averaged separately. N1 was defined as the most negative peak between 60 and 150 ms
PO3.15 Auditory N1 Component and Corollary Discharge: A Topographical Analysis
PO3.16 Evaluation of Brainstem Function in Patients with Spasmodic Dysphonia Using Vestibular Evoked Myogenic Potentials and Auditory Brainstem Responses Shahram Akrami1 *, Amir Arvin Sazgar2 , Kamyar Akrami3 , Jalal Mehdizadeh3 , Azar Feizi3 1 EMG Clinic, Dept. of Physical Medicine & Rehabilitation, Tehran University of Medical Sciences, Iran, 2 Dept. of Otolaryngology, University of Medical Sciences, Iran, 3 MG Clinic, Dept. of Physical Medicine & Rehabilitation, Tehran University of Medical Sciences, Iran E-mail address: [email protected] Background: The vestibular area is closer than the auditory region to nucleus ambiguus. If a ‘shared’ lesion involves regions of adjacent nuclei of the brainstem in patients with spasmodic dysphonia then vestibular area involvement is more possible than that of the auditory region. The authors hypothesize that lower brainstem lesions and involvement of descending pathways of the spinal tract may be the site of lesion in patients with spasmodic dysphonia. Methods: Ten patients with spasmodic dysphonia were tested using the auditory brainstem response (ABR) and vestibular evoked myogenic potentials (VEMPs). Results: No ABR abnormalities were found in right ears. Results of ABR on the left ear showed that one patient had abnormal ABR. This patient had severe sensorineural hearing loss on the left side. VEMPs displayed normal response in two patients bilaterally. First positive (p13) and second negative (n23) waves of VEMP could not be recorded in three cases unilaterally and in five patients bilaterally.
Posters: PO3. Evoked Potentials
radices, indirectly reflecting the functional condition of a horse tail and a spinal cord cone. However, other tendency in increase indicators latency N22 has been revealed also. The more there was an increase of latency N22, the treatment of a painful syndrome and restoration at compressing radix was stretched on long time. Conclusions: Thus, research SSEP at intervertebral disk’s hernias on lumbo-sacral osteochondrosis reveals changes in an increase kind latency N22, testifying about compressing a radix, and also can serve as criterion of expressiveness of a compression and duration of spent therapy.
poststimulus. Amplitudes were measured with respect to an average voltage during the 50 ms prestimulus. Results: The amplitude of N1 components were lower during vocalizing than during the silent baseline condition. Conclusions: These results may replicate that the auditory N1 component may reflect the effects of corollary discharge.
PO3.13 Correlation between Intracranial Pressure and Visual Evoked Potential Findings in Children with Craniosynostosis
Akira Iwanami *, Yuka Okajima, Nobumasa Kato Dept. of Psychiatry, Showa University School of Medicine, Japan E-mail address: [email protected]
In Soo Joo *, Seung-Hyeon Yeo, Wen-Yu Li Dept. of Neurology, Ajou University School of Medicine, Korea E-mail address: [email protected]
Background: Corollary discharge is a brain electrical activity associated with self-monitoring, which distinguishes self from others in thoughts or behaviors. Using event-related potential (ERP) recordings in humans, it is possible to assess corollary discharge non-invasively. Several previous studies have revealed that the amplitude of the N1 component elicited during an auditory task is reduced while a subject is vocalizing, which may index the effect of corollary discharge on auditory ERPs. In this study, we attempted to assess the effect of vocalizing on the N1 component using a topographical analysis. Methods: Subjects were 15 healthy volunteers. Event-related potentials were recorded during a passive auditory task while subjects were silent, while subjects were vocalizing, and while subjects listened to the vocalizing. Subjects were presented with a series of 500 auditory stimuli with a fixed interstimulus interval of 500 ms. In the task, 90% of the stimuli were tones of 1 KHz, and the other 10% tones of 2 KHz. According to the international 10 20 system, the scalp electroencephalogram (EEG) was recorded at Fp1, Fp2, F3, F4, C3, C4, P3, P4, O1, O2, F7, F8, T3, T4, T5, T6, Fz, Cz, and Pz monopolarly. Vertical and horizontal electrooculograms (EOG) were recorded from electrodes placed below and at the outer canthus of the right eye. EEG samples were acquired every 1 ms from 50 ms before to 450 ms after the stimulus onset. The responses to frequent and rare tones and were averaged separately. N1 was defined as the most negative peak between 60 and 160 ms poststimulus. Amplitudes were measured with respect to an average voltage during the 50 ms prestimulus. Results: The distribution of the N1 component differed among the three conditions. Conclusions: These results suggested that corollary discharge may have different effects among the subcomponents of the auditory N1.
Background: Craniosynostosis, the premature closure of one or more cranial sutures, can cause elevated intracranial pressure (ICP) and optic nerve damage. Visually evoked potentials (VEP) are commonly used for assessing the anterior and posterior visual pathways. We evaluated the correlation between ICP and VEP findings in children with craniosynostosis. Methods: From January 2008 until December 2008, 29 children (13 males and 19 females) with craniosynostosis were elicited by flashing light using light emitting diode goggles in our neurophysiological laboratory. Every child underwent ophthalmological examination for exclusion of ocular or optic nerve problems not related with elevated ICP. Lumbar puncture was performed in order to measure ICP. Results: In 29 children (mean age 2.6 years, range from 1 to 8 years) VEP and ICP were obtained preoperatively. Of them, 13 (44.8%) children showed absent or delayed N75 bilaterally on VEP except one. Mean ICP of all patients measured via lumbar puncture was 26.4±7.7 cmH2 O (range 14 to 42.5 cmH2 O). There was no significant difference in the mean ICP values between patients showing abnormal (13 patients, 26.4±7.9 cmH2 O) and normal VEP findings (16 patients, 26.4±7.8 cmH2 O). And the age of patient was also not significantly different between two groups (p = 0.44). Conclusions: Quite a few craniosynostosis patients showed abnormal patterns on VEP and, therefore, VEP could be a useful diagnostic tool for early detection of visual compromises in these patients. But the results suggest that abnormal VEP patterns do not always reflect an elevated ICP and could not be an absolute but helpful criterion to make a decision for the need of surgical treatment in children with craniosynostosis. PO3.14 Effects of Corollary Discharge on Auditory N1 Component of Event-Related Potentials in Healthy Subjects Akira Iwanami *, Yuka Okajima, Nobumasa Kato Dept. of Psychiatry, Showa University School of Medicine, Japan E-mail address: [email protected] Background: Corollary discharge is a brain electrical activity associated with self-monitoring, which distinguishes self from others in thoughts or behaviors. Corollary discharge can be non-invasively assessed using eventrelated potential (ERP) recordings in humans. Several previous studies have revealed that the amplitude of the N1 component elicited during an “odd-ball” task is reduced while a healthy subject is vocalizing, which may index the effect of corollary discharge on auditory ERPs. In this study, we attempted to assess the effect of vocalizing on the N1 component during a passive oddball task in healthy adults. Methods: Event-related potentials were recorded during a passive auditory task while subjects were silent, while subjects were vocalizing, and while subjects listened to the vocalizing. Subjects were presented with a series of 500 auditory stimuli with a fixed interstimulus interval of 500 ms. In the task, 90% of the stimuli were tones of 1 KHz, and the other 10% tones of 2 KHz. The stimulus intensity was 75 dBSPL, and the tone duration 50 ms, with a rise/fall time of 10 ms. According to the international 10 20 system, the scalp electroencephalogram (EEG) was recorded. The bandpass was set at 0.15 120 Hz. Vertical and horizontal electrooculograms (EOG) were recorded from electrodes placed below and at the outer canthus of the right eye. EEG samples were acquired every 1 ms from 50 ms before to 450 ms after the stimulus onset. The responses to frequent and rare tones and were averaged separately. N1 was defined as the most negative peak between 60 and 150 ms
PO3.15 Auditory N1 Component and Corollary Discharge: A Topographical Analysis
PO3.16 Evaluation of Brainstem Function in Patients with Spasmodic Dysphonia Using Vestibular Evoked Myogenic Potentials and Auditory Brainstem Responses Shahram Akrami1 *, Amir Arvin Sazgar2 , Kamyar Akrami3 , Jalal Mehdizadeh3 , Azar Feizi3 1 EMG Clinic, Dept. of Physical Medicine & Rehabilitation, Tehran University of Medical Sciences, Iran, 2 Dept. of Otolaryngology, University of Medical Sciences, Iran, 3 MG Clinic, Dept. of Physical Medicine & Rehabilitation, Tehran University of Medical Sciences, Iran E-mail address: [email protected] Background: The vestibular area is closer than the auditory region to nucleus ambiguus. If a ‘shared’ lesion involves regions of adjacent nuclei of the brainstem in patients with spasmodic dysphonia then vestibular area involvement is more possible than that of the auditory region. The authors hypothesize that lower brainstem lesions and involvement of descending pathways of the spinal tract may be the site of lesion in patients with spasmodic dysphonia. Methods: Ten patients with spasmodic dysphonia were tested using the auditory brainstem response (ABR) and vestibular evoked myogenic potentials (VEMPs). Results: No ABR abnormalities were found in right ears. Results of ABR on the left ear showed that one patient had abnormal ABR. This patient had severe sensorineural hearing loss on the left side. VEMPs displayed normal response in two patients bilaterally. First positive (p13) and second negative (n23) waves of VEMP could not be recorded in three cases unilaterally and in five patients bilaterally.