Effects of midazolam on high-frequency oscillations in amygdala and hippocampus of epilepsy patients.

High-frequency oscillations (HFOs) are associated with normal brain function, but are also increasingly recognized as potential biomarkers of epileptogenic tissue. Considering the important role of interneuron activity in physiological HFO generation, we studied their modulation by midazolam (MDZ), an agonist of γ-aminobutyric acid type A (GABA)-benzodiazepine receptors. Here, we analyzed 80 intracranial electrode contacts in amygdala and hippocampus of 13 patients with drug-refractory focal epilepsy who had received MDZ for seizure termination during presurgical monitoring.

Long-term versus short-term memory deficits for faces in temporal lobe and generalized epilepsy patients.

It is still an open question whether short-term and long-term memory are two anatomically dissociable memory systems working in parallel or whether they are represented by neural circuits within similar cortical areas. Epilepsy may be used as a model to study these memory processes. We hypothesized that a double dissociation of short-term and long-term memory exists in temporal lobe epilepsy (TLE) and idiopathic generalized epilepsy (IGE).

Long-term face memory as a measure of right temporal lobe function in TLE: the Alsterdorfer Faces Test.

There is a shortage of neuropsychological tests to assess right temporal lobe memory function in TLE patients. Although right temporal lobe dominance for face memory is well established, neuropsychological studies on face memory in epilepsy surgery candidates have reported mixed results. These latter studies in TLE patients mostly concentrated on immediate face recognition.

Remembering versus knowing during face recognition in unilateral temporal lobe epilepsy patients with or without hippocampal sclerosis.

Recognition memory involves knowing an item was learned (familiarity) and remembering contextual details about the prior learning episode (recollection). We tested three competing hypotheses about the role of the hippocampus in recollection and familiarity. It mediates either recollection or familiarity, or serves both processes.

Face memory in MRI-positive and MRI-negative temporal lobe epilepsy.

Purpose: Effects of MRI-positive (MRI(+)) as compared to MRI-negative (MRI(-)) temporal lobe epilepsy (TLE) on face memory are not yet known.

Methods: We studied 24 MRI(-) (11 right/13 left) and 20 MRI(+) (13 right/7 left) TLE patients, 12 generalized epilepsy patients, and 12 healthy subjects undergoing diagnostic workup with 24-72-h Video-EEG-monitoring. Twenty faces were shown, and had to be recognized from 40 faces immediately and after a 24-h delay.

A novel high channel-count system for acute multisite neuronal recordings.

Multisite recording represents a suitable condition to study microphysiology and network interactions in the central nervous system and, therefore, to understand brain functions. Several different materials and array configurations have been proposed for the development of new probes utilized to record brain activity from experimental animal models. We describe new multisite silicon probes that broaden the currently available application base for neuroscientists.