PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Epilepsy, Reflex”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources
PubMed1990

Seizure generation mechanisms in reflex epilepsy.

To know the seizure generation mechanisms in reflex epilepsy, we performed red flicker and flickering geometric pattern stimulations for photosensitive epilepsy, and neuropsychological EEG activation for graphogenic epilepsy. These activations were effective to provoke seizure discharges. The EEG discharges of absence seizure in photosensitive epilepsy started mainly from the posterior regions, which became evident by the reduction of stimulus intensity. Mental activity performed with the hands provoked the central-dominant discharges with unilateral myoclonic seizure as well as generalized discharges with bilateral myoclonic seizure in graphogenic epilepsy. These findings suggest that the initiation of these seizures may relate to the hyperexcitability of the focal cortical areas, which correspond to those activated by the special EEG activation.

Adolescent↗
PubMed1992

The effects of AMPA receptor antagonists on kindled seizures and on reflex epilepsy in rodents and primates.

Two potent glutamate antagonists, NBQX and GYKI 52466, that act selectively on non-NMDA receptors, have been tested for anticonvulsant activity in 3 models of reflex epilepsy (sound-induced seizures in DBA/2 mice and in genetically epilepsy-prone rats and photically-induced myoclonus in Papio papio) and in amygdala kindled rats. Both compounds potently but transiently suppress reflexly-induced epileptic responses. GYKI 52466 also reduces behavioral seizures and afterdischarge duration in amygdala kindled rats, but with a lower potency than it suppresses reflex epilepsy. These data are similar to earlier results with antagonists acting selectively on NMDA receptors; they do not support a specific involvement of enhanced AMPA receptor sensitivity as a major factor in the expression of kindled seizures.

Acoustic Stimulation↗
PubMed1996

[Reflex epilepsy with seizures induced by mental calculation, playing chess and scrabble].

Reflex seizures induced by higher mental activity is rare. We report the case of a young man with myoclonic jerks and generalized tonico-clonic convulsion precipitated by calculation, playing chess and scrabble. Routine EEG, including hyperventilation and photic stimulation, showed no abnormality. Tests stimulation procedures, including spatial tasks, induced focal and generalized EEG spike-wave complex and myoclonic jerks. Valproate was effective in reducing epileptic seizures during a follow-up period of three years. Comparison of our case with previously reported reflex epilepsy with seizures induced by higher mental activity is discussed.

Adult↗
PubMed1990

What the reflex epilepsies reveal about the physiology of ideation.

A review of the phenomena involved in reflex epilepsy illustrates that ideas have a neural substrate. The ideational substratum and, at times, associative links to other stimuli have physiological (epileptogenic) power. These phenomena can be applied to events in some psychopathological disorders.

Arousal↗
PubMed2003

Reflex myoclonic epilepsy in infancy: a benign age-dependent idiopathic startle epilepsy.

Reflex myoclonic epilepsy of infancy is an idiopathic epileptic disorder characterized by myoclonic attacks, with onset in the first 2 years of life precipitated exclusively by unexpected tactile or auditory stimuli. We report on a 9 month-old infant with myoclonic attacks, which consisted of frequent clusters of up to 10 symmetric jerks affecting mainly the arms and the head occurring as reflex responses to unexpected auditory stimuli. There was no family history of epilepsy or febrile convulsions. Ictal EEG demonstrated a typical 3 Hz spike-wave pattern, while there were no abnormalities, either in wakefulness or during sleep. The neurodevelopmental examination was unremarkable and MRI of the brain was normal. The attacks disappeared 3 weeks after initiating sodium valproate, and have not reappeared since then (follow-up 3 years and 3 months); today, at 4 years of age, the patient has normal psycho-motor development. RMEI should be considered as an age-dependent, idiopathic, generalized epileptic syndrome with an apparently good prognosis[Published with video sequences].

Acoustic Stimulation↗
PubMed1989

Reflex epilepsy and nonketotic hyperglycemia in the elderly: a specific neuroendocrine syndrome.

We present five elderly patients with focal reflex or posture-induced seizures and nonketotic hyperglycemia (NKH). Each patient exhibited interictal focal findings, such as hemiparesis or hemisensory or aphasic deficits. With control of the hyperglycemia, the seizures stopped, and the neurologic deficits resolved. The syndrome of focal reflex epilepsy and neurologic deficits in the elderly is transient and almost invariably related to NKH, thus representing a specific neuroendocrine syndrome.

Aged↗
PubMed1996

Brain chimeras in birds: application to the study of a genetic form of reflex epilepsy.

A strain of chicken, called here FEpi (for Fayoumi epileptic), bearing an autosomal recessive mutation, exhibits a form of reflex epilepsy with EEG interictal paroxysmal manifestations and generalized seizures in response to either light or sound stimulations. By using the brain chimera technology, we demonstrate here that the epileptic phenotype can be partially or totally transferred from an FEpi to a normal chick by grafting specific regions of the embryonic brain. The mesencephalon contains the generator of all epileptic manifestations whether they involve visual or auditory neuronal circuits, with the exception of the abnormal EEG which is transmitted exclusively by telencephalic grafts. This analysis supports the hypothesis that certain forms of human and mammalian epilepsies have a brainstem origin.

Animals↗
PubMed1987

The genetic animal model of reflex epilepsy in the Mongolian gerbil: differential efficacy of new anticonvulsive drugs and prototype antiepileptics.

Four new anticonvulsive drugs were compared to four prototype antiepileptics regarding their differential efficacy, i.e. against tonic-clonic, myoclonic, and minor seizures, in reflex epilepsy in genetically epileptic gerbils. We distinguished at least three types of drugs: Phenytoin and ralitoline selectively prevented tonic-clonic seizures; the other drugs tested were active against all seizure types. However, carbamazepine and AHR-11748 were predominantly active against tonic-clonic seizures, whereas phenobarbital, valproate, gabapentin, and zonisamide equipotently suppressed both tonic-clonic and myoclonic seizures.

Animals↗
PubMed1991

Language-apparent reflex epilepsy.

An adolescent with photosensitive epilepsy had absence seizures reproduced by forced voluntary eye closure in light or in darkness, independent of eyelid immobilization or ocular elevation. Attacks preferably occurred while speaking Spanish, her second language, mediated through brief, strong, automatic closing of the eyes during difficult word retrieval. Complex other multidirectional ocular movements or blinking, cognitive and language tasks were ineffective. Frontorolandic cortical epileptogenesis is seemingly responsible for light-provoked seizures in Papio papio, acting via hyperexcitable neuronal facial aggregates (i.e. Baba and Wada). Since orbicularis oculi muscle fibers mediating strong and weak contractions are differentially innervated by the facial nuclei, we submit that critical threshold tonic activation of specific nuclear aggregates explains this language-apparent reflex epilepsy, triggered by extreme eye closure. A "dopamine connection hypothesis" linking periodic eye closure, effortful memory and photosensitivity, based on its putative evolutive significance, is discussed.

Adolescent↗