Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0014547 (focal epilepsy)
 1,627 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Benign focal epilepsy in childhood with centro-temporal spikes (BECTS) is one of the most common forms of epilepsy. Recent studies have questioned the benign nature of BECTS, as they have revealed neuropsychological deficits in many domains including language. The aim of this study was to investigate whether the epileptic discharges during the night have long-term effects on auditory processing, as reflected on electrophysiological measures, during the day, which could underline the language deficits. In order to address these questions we recorded base line electroencephalograms (EEG), sleep EEG and auditory event related potentials in 12 children with BECTS and in age- and gender-matched controls. In the children with BECTS, 5 had unilateral and 3 had bilateral spikes. In the 5 patients with unilateral spikes present during sleep, an asymmetry of the auditory event related component (P85-120) was observed contralateral to the side of epileptiform activity compared to the normal symmetrical vertex distribution that was noted in all controls and in 3 the children with bilateral spikes. In all patients the peak to peak amplitude of this event related potential component was statistically greater compared to the controls. Analysis of subtraction waveforms (deviant - standard) revealed no evidence of a mismatch negativity component in any of the children with BECTS. We propose that the abnormality of P85-120 and the absence of mismatch negativity during wake recordings in this group may arise in response to the long-term effects of spikes occurring during sleep, resulting in disruption of the evolution and maintenance of echoic memory traces. These results may indicate that patients with BECTS have abnormal processing of auditory information at a sensory level ipsilateral to the hemisphere evoking spikes during sleep.
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PMID:Evidence for a neurophysiologic auditory deficit in children with benign epilepsy with centro-temporal spikes. 1625 74

The relationship between epilepsy and psychosis is not well defined. Sensory gating is a possible endophenotype for psychosis, and has not been fully examined in epileptic patients. The authors examined 29 patients with focal epilepsy who were on antiepileptic medications, and 29 age-matched healthy comparison subjects, using a paired-stimulus (S1-S2) paradigm. P50 and N100 amplitudes or gating did not differ between the groups. The P200 was significantly smaller and did not gate as well in epileptic patients. Though alteration of sensory gating can be demonstrated in epileptic patients, it seems to be qualitatively different from alterations reported in association with schizophrenia.
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PMID:Mid-latency auditory-evoked responses and sensory gating in focal epilepsy: a preliminary exploration. 1696 93

The filtering of sensory information, also referred to as "sensory gating", is impaired in various neuropsychiatric diseases. In the auditory domain, sensory gating is investigated mainly as a response decrease of the auditory evoked potential component P50 from one click to the second in a double-click paradigm. In order to relate deficient sensory gating to anatomy, it is essential to identify the cortical structures involved in the generation of P50. However, the exact cerebral topography of P50 gating remains largely unknown. In a group of 17 patients with drug-resistant focal epilepsy, P50 was recorded invasively via subdural electrodes, and the topography of functionally indispensable ("eloquent") cortices was obtained by electrical stimulation mapping. These eloquent areas were involved in language, motor, and sensory functions. P50 could be identified in 13 patients in either temporal (n=8) or midfrontal sites (n=5). There were six occurrences (in five patients) of overlap of sites with maximal P50 responses and eloquent areas. Those were auditory (n=1), supplementary sensorimotor (n=3), primary motor (n=1), and supplementary negative motor (n=1). Results suggest that the early stage of sensory gating already involves a top-down modulation of sensory input by frontal areas.
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PMID:Towards a functional topography of sensory gating areas: invasive P50 recording and electrical stimulation mapping in epilepsy surgery candidates. 1751 93