The main focus of our laboratory is to understand molecular and cellular mechanisms underlying memory formation and storage. The brain contains a vast number of neurons, yet evidence suggests that only a small portion of them is involved in a given memory. However, the processes through which one neuron, rather than its neighbor, is selected for a particular memory circuit are largely unknown. Neuronal activity-dependent gene expression is implicated in these processes. In particular, the rapid and transient expression of immediate-early genes (IEGs), such as c-fos, zif268, and Arc, is a candidate for the initial cellular response that triggers subsequent molecular/cellular processes for memory formation. Our laboratory investigates roles of IEG expression in memory functions as well as pathological processes using rodents as model animals by various techniques in molecular biology, physiology, anatomy, genetics and behavioral sciences.