Wavelet-based Gaussian-mixture hidden Markov model for the detection of multistage seizure dynamics: a proof-of-concept study.

Background: Epilepsy is a common neurological disorder characterized by recurrent electrophysiological activities, known as seizures. Without the appropriate detection strategies, these seizure episodes can dramatically affect the quality of life for those afflicted. The rationale of this study is to develop an unsupervised algorithm for the detection of seizure states so that it may be implemented along with potential intervention strategies.

The role of altered tissue osmolality on the characteristics and propagation of seizure activity in the intact isolated mouse hippocampus.

Objectives: To study the role of altered tissue osmolality on the characteristics and propagation dynamics of seizure activity and on interictal activity, in a low-Mg(+2) artificial cerebrospinal fluid (ACSF) model of recurrent seizures, using the immature (P8-P25) intact isolated mouse hippocampus.

Methods: Recordings were obtained extracellularly from a single site in the CA1 region and from multiple sites along the septotemporal axis measuring spontaneous epileptiform field activity in ACSFs of different osmolalities.

Results: In normal osmolar ACSF (310 mOsmol), the average duration of recorded seizures was 90+/-10 s and the average peak amplitude was 0.

Mechanisms of morphine enhancement of spontaneous seizure activity.

Background: High-dose opioid therapy can precipitate seizures; however, the mechanism of such a dangerous adverse effect remains poorly understood. The aim of our study was to determine whether the neuroexcitatory activity of high-dose morphine is mediated by selective stimulation of opioid receptors.

Methods: Mice hippocampi were resected intact and bathed in low magnesium artificial cerebrospinal fluid to induce spontaneous seizure-like events recorded from CA1 neurons.

Transition to seizures in the isolated immature mouse hippocampus: a switch from dominant phasic inhibition to dominant phasic excitation.

The neural dynamics and mechanisms responsible for the transition from the interictal to the ictal state (seizures) are unresolved questions in epilepsy. It has been suggested that a shift from inhibitory to excitatory GABAergic drive can promote seizure generation. In this study, we utilized an experimental model of temporal lobe epilepsy which produces recurrent seizure-like events in the isolated immature mouse hippocampus (P8-16), perfused with low magnesium ACSF, to investigate the cellular dynamics of seizure transition.