This variability, including in the efficacy of gold-standard pharmacological interventions 5, suggests the need for targeted therapeutics that would in turn require the identification of molecular or cellular mechanistic targets. It is increasingly recognized that absence epilepsy is not a benign condition and that long-term outcomes are variable 3, 4, 5, 6. However, the way that SWDs disrupt normal neuronal activity to produce unconsciousness is not known. Electroencephalography (EEG) during absence seizures reveals abnormal paroxysmal brain rhythms called spike-wave discharges (SWDs) associated with behavioral changes. The altered consciousness in absence seizures can be highly disabling, characterized by behavioral arrest and unresponsiveness 1, 2. Our findings demonstrate that prolonged brain state changes precede consciousness-impairing seizures, and that during seizures distinct functional groups of cortical and thalamic neurons produce an overall transient firing increase followed by a sustained firing decrease, and increased rhythmicity.Ībsence epilepsy causes recurring brief episodes of impaired consciousness. 40–60 s before seizure onset there begins a decline in low frequency electroencephalographic activity, neuronal firing, and behavior, but an increase in higher frequency electroencephalography and rhythmicity of neuronal firing.

Individual cortical and thalamic neurons express one of four distinct patterns of seizure-associated activity, one of which causes a transient initial peak in overall firing at seizure onset, and another which drives sustained decreases in overall firing. Neuronally, seizures feature overall decreased but rhythmic firing of neurons in cortex and thalamus. Here we report that an awake female rat model recapitulates the behavioral, electroencephalographic, and cortical functional magnetic resonance imaging characteristics of human absence seizures. Nature Communications volume 14, Article number: 117 ( 2023)Ībsence seizures are brief episodes of impaired consciousness, behavioral arrest, and unresponsiveness, with yet-unknown neuronal mechanisms. Decreased but diverse activity of cortical and thalamic neurons in consciousness-impairing rodent absence seizures

Eeg findings absence seizures