exerted by Golgi cells, whereas those with α 6 subunits,which are more sensitive to GABA, are distributed both inside and outside postsynaptic densities and could thus determine the strength of tonic inhibition following spillover of GABA released from either Golgi cells 52–56 or astrocytes 57 . In effect, Golgi cell inhibition of granule cells may downregulate the level of LTP induction at the mossy fibre–granule cell synapse discussed above 58,59 .