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P314: Excitability changes in spinal reciprocal inhibitory circuit induced by periodical sensory inputs
Abstracts of Poster Presentations / Clinical Neurophysiology 125, Supplement 1 (2014) S1–S339
latencies, we think that prolongation of LLR II and cortical relay time in PD without apraxia reflects a deficit in PD probably other than dopaminergic deficit because we examined our cases under optimum dopaminergic treatment when they do not have PD symptoms. However, in PD apraxia functional magnetic resonance imaging studies also showed overactivity of default mode which may be the underlying factor of shortening of cortical relay time.
P314 Excitability changes in spinal reciprocal inhibitory circuit induced by periodical sensory inputs S. Kubota 1 , M. Hirano 1 , T. Morishita 1,2 , K. Uehara 1,2 , K. Funase 1 1 Hiroshima University, Higashihiroshima, Japan; 2 Research Fellow of the Japan Society for the Promotion of Science, Tokyo, Japan Question: Our question is how sensory inputs from antagonist muscle influence the excitability changes in reciprocal Ia inhibitory circuit. Methods: The degree of reciprocal Ia inhibition and the conditioning effects of transcranial magnetic stimulation (TMS) on the Soleus (Sol) H-reflex were examined in ten healthy subjects. The degree of reciprocal Ia inhibition was determined via short-latency (condition-test interval: 1, 2, 3ms) suppression of the Sol H-reflex by conditioning stimulation of common peroneal nerve (CPN). The TMS-conditioning effects on the Sol H-reflex was measured at short-latency condition-test intervals (-3, -2, -1, 0ms). Negative condition-test intervals indicate that the conditioning stimulus was applied after the test stimulation. The stimulus position for TMS was defined as the site where TMS consistently resulted in the largest Sol motor evoked potential. The periodical electrical stimulation was applied on CPN every 1sec (100Hz-5train) at motor threshold intensity of tibialis anterior muscle. The degree of reciprocal Ia inhibition and the TMS conditioned H-reflex amplitude were assessed before, immediately after, and 15 minutes after of the electrical stimulation. Results: The degree of reciprocal Ia inhibition and the amplitude of the TMS-conditioned H-reflex around -1ms were increased by periodical sensory inputs from antagonist muscle, which were not concomitant with the change in Sol motoneuron excitability. Conclusions: Our results indicated that Ia inhibitory interneurons are sensitive to periodical sensory inputs, because the change in the amplitude of the TMS-conditioned H-reflex was only observed in the specific condition-test interval which is assumed to be mediated by Ia inhibitory interneurons.
P315 Influence of limb temperature on cutaneous silent periods M. Kofler 1 , J. Valls-Solé 2 , P. Vasko 3 , V. Boˇcek 3 , I. Štetkárová 3 1 Hochzirl Hospital, Neurology, Zirl, Austria, Austria; 2 Hospital Clinic I Provincial de Barcelona, Barcelona, Spain, Spain; 3 Charles University, Third Faculty of Medicine, Department of Neurology, Prague, Czech Republic, Czech Republic Objective: The cutaneous silent period (CSP) is a spinal inhibitory reflex mediated by A-delta fibers. The effect of limb temperature on CSPs has so far not been assessed. Methods: In 27 healthy volunteers (11 males; age 22 -58 years) we recorded median nerve motor and sensory action potentials, median nerve F-wave and CSPs induced by noxious digit II stimulation in thenar muscles in a baseline condition at room temperature, and after randomly submersing the forearm in 42°C warm or 15°C cold water for 20 minutes each. Results: In cold limbs, distal and proximal motor and sensory latencies as well as F-wave latencies were prolonged. Motor and sensory nerve conduction velocities were reduced. Compound motor and sensory nerve action potential amplitudes did not differ significantly from baseline. CSP onset and end latencies were more delayed than distal and proximal median nerve motor and sensory latencies, whereas CSP duration was not affected. In warm limbs, opposite but smaller changes were seen in nerve conduction studies and CSPs. Conclusion: The observed CSP shift “en bloc” towards longer latencies without affecting CSP duration during limb cooling concurs with slower conduction velocity in large-diameter efferent and small-diameter afferent myelinated fibers. Correlation of small- to large-diameter fiber slowing reveals a similar sensitivity to temperature of both fiber types relative to their conduction at normal temperature, which, however, results in a differential delay in corresponding latencies.
S133
Significance: Limb temperature should be taken into account when testing CSPs in the clinical setting, as different limb temperatures affect CSP latencies more than large-diameter fiber conduction function.
P316 Sympathetic autonomic involvement in cluster headache: is it a systemic or cranial phenomenon? B. Mutluay, Ö. Altıokka, M. Öztürk, Y. Altunkaynak, A. Soysal, S. Baybas Bakirkoy Research and Training Hospital for Psychiatry, Neurology and Neurosurgery, Neurology, Istanbul, Turkey Question: To investigate the extent of sympathetic autonomic involvement in cluster headache (CH) using face in contrast to extremity sympathetic skin responses (SSR) during attack and remission phases. Material and method: Nineteen drug-free CH patients (16 male, 3 female) and 20 gender and age matched, healthy volunteers were included. SSR recordings of the forehead, hand and foot, and R-R interval variations (RRIV) were evaluated both in attack and remission phases. Results: Mean latency of face SSRs was longer and amplitude was lower on the symptomatic side compared to the asymptomatic side and controls (p=0.005, p=0.068); although SSR was obtained from both face and extremities during attack and remission periods, there were no differences in latency or amplitude of extremity SSRs compared to controls. Only three patients were determined to have orthostatic hypotension (OH) during attacks (16%), and none had OH in remission. No significant difference was determined for RRIV values during attack and remission in patients or controls. No significant association was identified between SSRs, RRIV, OH and duration of illness, average number of episodes per year, average duration of cluster periods in days, average number of attacks per day, pain duration. Conclusion: SSRs recorded from the face are more sensitive than extremity recordings and RRIV in CH suggesting that sympathetic autonomic dysfunction in CH might mostly be limited to the cranial area.
P317 The effect of lemon juice and water on oropharyngeal swallowing and the gustato-facial reflexes in healthy adult subjects F. Tokucoglu 1 , N. Gurgor 1 , N. Hasanzadeh 1 , T. Kurt Incesu 1 , S. Arici 1 , Y. Secil 1 , C. Ertekin 1,2 1 Izmir Katip Celebi University Ataturk Resarch and Training Hospital, Neurology, Izmir, Turkey; 2 Invited researcher, Neurology, Izmir, Turkey Question: It is well known that the sour taste can improve the oropharyngeal dysphagia. However, the effect of increasing volumes of lemon juice and water on oropharyngeal dysphagia and gustato-facial reflexes has not been evaluated yet. Method: Twenty-one healthy adult subjects were investigated in our study. Respiratory signals, submental, orbicularis oculi (OC) and orbicularis oris (OR) muscles EMG activities were recorded simultaneously during swallowing of 5, 10, 15 and 20 ml lemon juice and water. Recordings were made consecutively during 60 seconds. Thesynchronization of OR and OC muscles was evaluated. Results: Increased of volumes of both lemon juice and water lead to increase of frequency and duration of swallows and duration of submental muscle EMG activities. Effects of pure lemon juice were more prominent than water (p<0.05).Synchronization of OR and OC muscles during swallows was proportional to increase of volume.There was no difference between lemon juice and water concerning the effects of volume increase. Conclusions: The sour taste significantly facilitates the swallowing when compared to water. The increase of the volume may cause the rise of the gustato-facial reflexes during the water and lemon juice.
P318 The effect of cold on trigeminal conduction system R. Inan 1 , M. Kızıltan 2 Dr. Luetfi Kırdar Kartal Training and Researching Hospital, Neurology, Istanbul, Turkey; 2 Istanbl University Cerrahpasa Faculty of Medicine, Neurology, Istanbul, Turkey 1
Question: Trigeminal nerve can be studied electrophysiologically by trigemino- trigeminal reflex methods such as masseter inhibitory reflex; somatosensorial evoked potentials (SEP) and motor evoked potentials
latencies, we think that prolongation of LLR II and cortical relay time in PD without apraxia reflects a deficit in PD probably other than dopaminergic deficit because we examined our cases under optimum dopaminergic treatment when they do not have PD symptoms. However, in PD apraxia functional magnetic resonance imaging studies also showed overactivity of default mode which may be the underlying factor of shortening of cortical relay time.
P314 Excitability changes in spinal reciprocal inhibitory circuit induced by periodical sensory inputs S. Kubota 1 , M. Hirano 1 , T. Morishita 1,2 , K. Uehara 1,2 , K. Funase 1 1 Hiroshima University, Higashihiroshima, Japan; 2 Research Fellow of the Japan Society for the Promotion of Science, Tokyo, Japan Question: Our question is how sensory inputs from antagonist muscle influence the excitability changes in reciprocal Ia inhibitory circuit. Methods: The degree of reciprocal Ia inhibition and the conditioning effects of transcranial magnetic stimulation (TMS) on the Soleus (Sol) H-reflex were examined in ten healthy subjects. The degree of reciprocal Ia inhibition was determined via short-latency (condition-test interval: 1, 2, 3ms) suppression of the Sol H-reflex by conditioning stimulation of common peroneal nerve (CPN). The TMS-conditioning effects on the Sol H-reflex was measured at short-latency condition-test intervals (-3, -2, -1, 0ms). Negative condition-test intervals indicate that the conditioning stimulus was applied after the test stimulation. The stimulus position for TMS was defined as the site where TMS consistently resulted in the largest Sol motor evoked potential. The periodical electrical stimulation was applied on CPN every 1sec (100Hz-5train) at motor threshold intensity of tibialis anterior muscle. The degree of reciprocal Ia inhibition and the TMS conditioned H-reflex amplitude were assessed before, immediately after, and 15 minutes after of the electrical stimulation. Results: The degree of reciprocal Ia inhibition and the amplitude of the TMS-conditioned H-reflex around -1ms were increased by periodical sensory inputs from antagonist muscle, which were not concomitant with the change in Sol motoneuron excitability. Conclusions: Our results indicated that Ia inhibitory interneurons are sensitive to periodical sensory inputs, because the change in the amplitude of the TMS-conditioned H-reflex was only observed in the specific condition-test interval which is assumed to be mediated by Ia inhibitory interneurons.
P315 Influence of limb temperature on cutaneous silent periods M. Kofler 1 , J. Valls-Solé 2 , P. Vasko 3 , V. Boˇcek 3 , I. Štetkárová 3 1 Hochzirl Hospital, Neurology, Zirl, Austria, Austria; 2 Hospital Clinic I Provincial de Barcelona, Barcelona, Spain, Spain; 3 Charles University, Third Faculty of Medicine, Department of Neurology, Prague, Czech Republic, Czech Republic Objective: The cutaneous silent period (CSP) is a spinal inhibitory reflex mediated by A-delta fibers. The effect of limb temperature on CSPs has so far not been assessed. Methods: In 27 healthy volunteers (11 males; age 22 -58 years) we recorded median nerve motor and sensory action potentials, median nerve F-wave and CSPs induced by noxious digit II stimulation in thenar muscles in a baseline condition at room temperature, and after randomly submersing the forearm in 42°C warm or 15°C cold water for 20 minutes each. Results: In cold limbs, distal and proximal motor and sensory latencies as well as F-wave latencies were prolonged. Motor and sensory nerve conduction velocities were reduced. Compound motor and sensory nerve action potential amplitudes did not differ significantly from baseline. CSP onset and end latencies were more delayed than distal and proximal median nerve motor and sensory latencies, whereas CSP duration was not affected. In warm limbs, opposite but smaller changes were seen in nerve conduction studies and CSPs. Conclusion: The observed CSP shift “en bloc” towards longer latencies without affecting CSP duration during limb cooling concurs with slower conduction velocity in large-diameter efferent and small-diameter afferent myelinated fibers. Correlation of small- to large-diameter fiber slowing reveals a similar sensitivity to temperature of both fiber types relative to their conduction at normal temperature, which, however, results in a differential delay in corresponding latencies.
S133
Significance: Limb temperature should be taken into account when testing CSPs in the clinical setting, as different limb temperatures affect CSP latencies more than large-diameter fiber conduction function.
P316 Sympathetic autonomic involvement in cluster headache: is it a systemic or cranial phenomenon? B. Mutluay, Ö. Altıokka, M. Öztürk, Y. Altunkaynak, A. Soysal, S. Baybas Bakirkoy Research and Training Hospital for Psychiatry, Neurology and Neurosurgery, Neurology, Istanbul, Turkey Question: To investigate the extent of sympathetic autonomic involvement in cluster headache (CH) using face in contrast to extremity sympathetic skin responses (SSR) during attack and remission phases. Material and method: Nineteen drug-free CH patients (16 male, 3 female) and 20 gender and age matched, healthy volunteers were included. SSR recordings of the forehead, hand and foot, and R-R interval variations (RRIV) were evaluated both in attack and remission phases. Results: Mean latency of face SSRs was longer and amplitude was lower on the symptomatic side compared to the asymptomatic side and controls (p=0.005, p=0.068); although SSR was obtained from both face and extremities during attack and remission periods, there were no differences in latency or amplitude of extremity SSRs compared to controls. Only three patients were determined to have orthostatic hypotension (OH) during attacks (16%), and none had OH in remission. No significant difference was determined for RRIV values during attack and remission in patients or controls. No significant association was identified between SSRs, RRIV, OH and duration of illness, average number of episodes per year, average duration of cluster periods in days, average number of attacks per day, pain duration. Conclusion: SSRs recorded from the face are more sensitive than extremity recordings and RRIV in CH suggesting that sympathetic autonomic dysfunction in CH might mostly be limited to the cranial area.
P317 The effect of lemon juice and water on oropharyngeal swallowing and the gustato-facial reflexes in healthy adult subjects F. Tokucoglu 1 , N. Gurgor 1 , N. Hasanzadeh 1 , T. Kurt Incesu 1 , S. Arici 1 , Y. Secil 1 , C. Ertekin 1,2 1 Izmir Katip Celebi University Ataturk Resarch and Training Hospital, Neurology, Izmir, Turkey; 2 Invited researcher, Neurology, Izmir, Turkey Question: It is well known that the sour taste can improve the oropharyngeal dysphagia. However, the effect of increasing volumes of lemon juice and water on oropharyngeal dysphagia and gustato-facial reflexes has not been evaluated yet. Method: Twenty-one healthy adult subjects were investigated in our study. Respiratory signals, submental, orbicularis oculi (OC) and orbicularis oris (OR) muscles EMG activities were recorded simultaneously during swallowing of 5, 10, 15 and 20 ml lemon juice and water. Recordings were made consecutively during 60 seconds. Thesynchronization of OR and OC muscles was evaluated. Results: Increased of volumes of both lemon juice and water lead to increase of frequency and duration of swallows and duration of submental muscle EMG activities. Effects of pure lemon juice were more prominent than water (p<0.05).Synchronization of OR and OC muscles during swallows was proportional to increase of volume.There was no difference between lemon juice and water concerning the effects of volume increase. Conclusions: The sour taste significantly facilitates the swallowing when compared to water. The increase of the volume may cause the rise of the gustato-facial reflexes during the water and lemon juice.
P318 The effect of cold on trigeminal conduction system R. Inan 1 , M. Kızıltan 2 Dr. Luetfi Kırdar Kartal Training and Researching Hospital, Neurology, Istanbul, Turkey; 2 Istanbl University Cerrahpasa Faculty of Medicine, Neurology, Istanbul, Turkey 1
Question: Trigeminal nerve can be studied electrophysiologically by trigemino- trigeminal reflex methods such as masseter inhibitory reflex; somatosensorial evoked potentials (SEP) and motor evoked potentials