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Contingent Negative Variation (contingent + negative_variation)
Selected AbstractsInterictal and Postictal Contingent Negative Variation in Migraine Without AuraHEADACHE, Issue 1 2001E.J.C.M. Mulder MSc Cortical hyperexcitability is thought to explain the more enhanced contingent negative variation (CNV) amplitudes and impaired CNV habituation that have been found during the interictal period in migraine without aura. These CNV characteristics have been shown to normalize to the level of healthy controls during an attack. This study aimed to replicate the interictal findings, and additionally examine whether migraineurs show reduced CNV amplitudes during the postattack period. Of 12 patients with migraine without aura and their sex- and age-matched healthy controls, CNV characteristics were recorded once in an interictal period, once during the postattack period within 30 hours after an attack that was treated with sumatriptan, and once after an attack that was treated with habitual nonvasoactive medication (counterbalanced). The present results did not confirm the enhanced CNV early and late wave amplitudes or impaired habituation, and cortical hyperexcitability that have previously been reported in the interictal period in patients with migraine without aura. During the postattack period, a decrease in CNV early and late amplitudes was found but only after sumatriptan use. This reduction in CNV amplitudes was most prominent over the frontal cortex and could reflect cortical hypoexcitability, possibly related to a suppression of central catecholaminergic activity by sumatriptan. [source] Planning of rapid aiming movements and the contingent negative variation: Are movement duration and extent specified independently?PSYCHOPHYSIOLOGY, Issue 3 2009Hartmut Leuthold Abstract In the present study we investigated motor programming constraints implied by the Generalized Motor Program (GMP) view. A response precuing task was used in which participants performed aiming movements of either short or long duration to either a near or a far target position. Precues provided either no advance information or partial information about extent or duration or fully specified the aiming movement. Reaction time (RT) decreased and late Contingent Negative Variation (CNV) amplitude increased with the amount of advance information. In contrast to predictions of the GMP view, the extent precue led to faster responses and larger CNV amplitude than the duration precue. We conclude that late CNV amplitude reflects independent parameter specification processes at an abstract level at which GMP's motor programming constraints do not apply. [source] Contingent negative variation elicited before jaw and tongue movementsJOURNAL OF ORAL REHABILITATION, Issue 12 2005K. YOSHIDA summary, Contingent negative variation (CNV) is a negative brain potential occurring between two successive stimuli when the first stimulus is a warning and the second stimulus requires a motor response. The CNV is interpreted as an expression of the cognitive processes in preparation for a response directed to a purpose. Using 19 electrodes we recorded CNVs for mouth opening, closing and lateral movements, tongue protrusion and hand extension in 10 healthy subjects. The aim of the study was to examine the motor control mechanism underlying jaw and tongue movements in a cognitive paradigm. The first stimulus (S1) served as a preparatory warning signal for the imperative stimulus (S2) 2 s after the S1. The subject performed the experimental tasks after the S2. The grand average CNVs for jaw and tongue movements showed a bilaterally widespread negativity with the maximum in the vertex region (Cz). The early CNV was identified about 400 ms after the S1 and its amplitude was highest at the midline-frontal area. The late CNV started approximately 1000 ms after the S1 with the maximum at Cz. The mean amplitude was significantly lower for hand extension than for the other tasks, and significantly higher for lateral movement than for mouth closing, suggesting that the CNV amplitude can be affected by the complexity of the task. The CNV recording may provide a means to study the neuronal activity necessary for the sensorimotor integration of jaw and tongue movements. [source] Interictal and Postictal Contingent Negative Variation in Migraine Without AuraHEADACHE, Issue 1 2001E.J.C.M. Mulder MSc Cortical hyperexcitability is thought to explain the more enhanced contingent negative variation (CNV) amplitudes and impaired CNV habituation that have been found during the interictal period in migraine without aura. These CNV characteristics have been shown to normalize to the level of healthy controls during an attack. This study aimed to replicate the interictal findings, and additionally examine whether migraineurs show reduced CNV amplitudes during the postattack period. Of 12 patients with migraine without aura and their sex- and age-matched healthy controls, CNV characteristics were recorded once in an interictal period, once during the postattack period within 30 hours after an attack that was treated with sumatriptan, and once after an attack that was treated with habitual nonvasoactive medication (counterbalanced). The present results did not confirm the enhanced CNV early and late wave amplitudes or impaired habituation, and cortical hyperexcitability that have previously been reported in the interictal period in patients with migraine without aura. During the postattack period, a decrease in CNV early and late amplitudes was found but only after sumatriptan use. This reduction in CNV amplitudes was most prominent over the frontal cortex and could reflect cortical hypoexcitability, possibly related to a suppression of central catecholaminergic activity by sumatriptan. [source] Planning of rapid aiming movements and the contingent negative variation: Are movement duration and extent specified independently?PSYCHOPHYSIOLOGY, Issue 3 2009Hartmut Leuthold Abstract In the present study we investigated motor programming constraints implied by the Generalized Motor Program (GMP) view. A response precuing task was used in which participants performed aiming movements of either short or long duration to either a near or a far target position. Precues provided either no advance information or partial information about extent or duration or fully specified the aiming movement. Reaction time (RT) decreased and late Contingent Negative Variation (CNV) amplitude increased with the amount of advance information. In contrast to predictions of the GMP view, the extent precue led to faster responses and larger CNV amplitude than the duration precue. We conclude that late CNV amplitude reflects independent parameter specification processes at an abstract level at which GMP's motor programming constraints do not apply. [source] Motor and nonmotor event-related potentials during a complex processing taskPSYCHOPHYSIOLOGY, Issue 6 2000Charles H. Hillman Identification of the necessary stimulus properties to elicit the stimulus preceding negativity (SPN) has been the impetus for numerous research studies. The current study was conducted to explore the possibility that the SPN is an index of cognitive resource allocation. An auditory warning stimulus (S1) indicated whether an easy or difficult discrimination would occur at S2. The SPN was collected before a nonmotor discrimination task (S2) that consisted of identifying the higher of two bars. To eliminate the influence of motor processing prior to S2, a button press on the side of the higher bar was held until perception of a response cue (S3). Additionally, P3, contingent negative variation (CNV), and behavioral measures were collected to assist in assessing the SPN. Results indicated that although the SPN exhibited increased negativity, no differences were observed based on task difficulty. However, task difficulty did affect P3 data for both the warning tone and the discrimination task, an effect not observed for the CNV. Overall, the data did not support that hypothesis that the SPN provides an index of cognitive demand. [source] |