Our new paper (https://biorxiv.org/content/10.1101/2023.04.17.537191v1) using thalamic data (!) explores how epileptic spikes block sleep spindle production during non-REM sleep. Discover the impact of epilepsy on sleep-dependent memory consolidation! #tootprint #epilepsy #neuroscience
Our study utilizes a unique dataset of simultaneous human and cortical recordings to investigate the relationship between epileptic activity and two of the cardinal sleep oscillations – slow oscillations (0.5 – 2 Hz) and #spindles (9-16 Hz) – generated in the thalamus.
Findings show how slow oscillations can facilitate both epileptic spikes and sleep spindles, which can lead to them looking correlated.
Epileptic spikes propagate from the cortex to the thalamus, with spikes tending to propagate to the thalamus more often in patients with sleep activated spikes (SWAS) and most in patients with epileptic encephalopathy (EE-SWAS). (see first figure below)
In patients with severe cognitive dysfunction, thalamic spikes reduced spindles for 30 seconds and decreased overall spindle rate. See below for an example sweep of data showing the reduction of thalamic spindle occurrence from spikes. (see second image below)
Our direct human observations point to a potential mechanism linking epileptiform spikes to cognitive dysfunction: sleep-activated epileptic spikes inhibit sleep spindles.