|Olfactory cortex anterior interneuron deep layer||Axon terminal||GabaB||GABAB presynaptic mechanism?||Baclofen suppresses field potentials at the intrinsic fiber synapses proximal to the pyramidal cell bodies (layer Ib) but not field potential at distal dendrites (layer Ia). afferent and intrinsic synaptic inputs may be differentially modulated by the activation of GABAB receptors and that this selective suppression is at least partially mediated via a presynaptic mechanism (at the interneuron terminals?) (Tang AC and Hasselmo ME, 1994352 ). Although both the soma and distal dendrites have both the fast and slow GABAA-mediated IPSCs, there is a greater proportion of slow component in the dendrites. Slow GABAA mediated IPSC component is regulated by presynaptic GABAB inhibition (at the interneuron terminals?) whereas the fast is not (Kapur A et al, 1997355 ).