Investigation into the effect of the general anaesthetics etomidate and ketamine on long-range coupling of population activity in the mouse neocortical slice

General anaesthetics have been hypothesised to ablate consciousness by decoupling intracortical neural connectivity. We explored this by investigating the effect of etomidate and ketamine on coupling of neural population activity using the low magnesium neocortical slice model. Four extracellular electrodes (50μm) were positioned in mouse neocortical slices (400μm thick) with varying separation. The effect of etomidate (24μM) and ketamine (16μM) on the timing of population activity recorded between channels was analysed. No decoupling was observed at the closest electrode separation of 0.2mm. At 4mm separation, decoupling was observed in 50% and 42% of slices during etomidate and ketamine delivery, respectively (P