The phantom of progressive dementia in epilepsy.
Age regression measures of memory in patients with epilepsy show that increased incidence of amnesia/dementia is not the consequence of progressive epilepsy.
Adolescent↗
Biomedical subjects
C Helmstaedter
Publications and source records attributed to C Helmstaedter.
Seizures during cognitive testing in patients with temporal lobe epilepsy: possibility of seizure induction by cognitive activation.
In 18 of 185 patients under consideration for epilepsy surgery, 20 seizures were observed during neuropsychological evaluation. We wished to determine whether the task at seizure onset corresponded neuropsychologically to lateralization of the epileptic focus. The patients' characteristics and the circumstances of the seizures were as follows: Fourteen patients had right temporal lobe epilepsy (RTE) and four had left temporal lobe epilepsy (LTE). Although a wide range of cognitive functions had been tested, all but one seizure occurred during assessment of memory performance. In the RTE patients, 12 of 16 seizures occurred during visual memory testing. Two seizures were observed during a verbal memory task, and one seizure was observed during mental rotation. In two LTE patients, seizures were elicited during verbal memory testing. Two LTE patients with seizures during visual memory testing had speech dominance of the right hemisphere. This high correspondence between the eliciting performance and the focus localization suggests that cognitive performances ipsilateral to the epileptic focus may affect seizure threshold in focal epilepsies.
Adult↗
Postictal courses of cognitive deficits in focal epilepsies.
Patients with epileptic seizures frequently complain of long-lasting cognitive impairment after a seizure. We evaluated this issue in 31 patients with epileptic seizures of a frontal (n = 8) or temporal lobe origin [right temporal lobe (RTL) n = 8/left temporal lobe (LTL) n = 15]. Seizures were secondarily generalized in 18 patients. Computerized testing of verbal and nonverbal recognition memory was performed before the seizure, directly after postictal reorientation, and 30 min and 1 h later. Repeated testing of 14 healthy persons served as control. The following results were obtained: Depending on seizure generalization, postictal reorientation times were 1-45 min. Frontal lobe seizures showed no effect on postictal memory performances, but verbal and visual recognition memory was significantly decreased after temporal lobe seizures. Decrease in either verbal or visual memory and time of recovery were related to lateralization of seizure onset. Functional recovery after reorientation lasted 30 min to 1 h. The decrease in performance was more severe after generalized seizures. Decision times during memory performance were not significantly affected by the seizures. Temporal lobe seizures lead to circumscribed and long-lasting memory deficits, which can be assumed to affect patients' capabilities seriously. Pre- and postictal testing is a useful tool for determining postictal cognitive impairment and in determining the site of seizure onset.
Adult↗