Oscillatory models of the hippocampus: A study of spatio-temporal patternsof neural activity

Spatial patterns of theta-rhythm activity in oscillatory models of the hipp ocampus are studied here using canonical models for both Hodgkin's class-1 and class-2 excitable neuronal systems. Dynamics of these models are studie d in both the frequency domain, to determine phase-locking patterns, and in the time domain, to determine the amplitude responses resulting from phase -locking patterns. Computer simulations presented here demonstrate that pha se deviations (timings) between inputs from the medial septum and the entor hinal cortex can create spatial patterns of theta-rhythm phase-locking. In this way, we show that the timing of inputs (not only their frequencies alo ne) can encode specific patterns of theta-rhythm activity. This study sugge sts new experiments to determine temporal and spatial synchronization.