The axon initial segment (AIS) is a specialized region of neurons where action potentials are initiated. The AIS contains a unique repertoire of ion channels and receptors, including receptors for GABA and glutamate, the two major neurotransmitters in the brain. It is, though, unclear how these AIS receptors affect neuronal action potential firing patterns. The molecular mechanisms by which they might exert their effects also remain to be elucidated. We will investigate this in hippocampal neurons using electrophysiological and imaging approaches. This will help us better understand information processing in hippocampal neurons, which critically influence many physiological conditions like memory formation.