Impact of Spikelets on Hippocampal CA1 Pyramidal Cell Activity During Spatial Exploration

Abstract

Space and Spikelets In neurons, spikelets are voltage fluctuations of small amplitude with a spike-like waveform. Spikelets are difficult to detect with extracellular techniques traditionally used to record neuronal activity in freely moving animals. Epsztein et al. (p. 474 ) used head-anchored whole-cell recordings to analyze spikelet activity during spatial exploration in freely moving rats. A high incidence of spikelets was often followed by action potentials. Like action potentials, spikelets were all-or-none, but had different kinetics and amplitude, and were clearly distinct from excitatory postsynaptic potentials and occurred to a different extent in different cells. In cells with clear place fields, spikelets had similar spatial firing preferences, as did regular action potentials. Thus, spatially modulated spikelets may be involved in information processing in cortical neuronal networks.