Coding of stimulus location by spike timing in rat somatosensory cortex

Although the timing of single spikes is known to code for time-varying stimulus features, it remains unclear whether time is also important in coding of static stimulus variables. We review a new information theoretic method for analyzing spike timing codes and apply it to single neurons recorded from the somatosensory cortex of the rat. We found that precise spike timing increases the information transmitted about stimulus location by a substantial amount, compared to that transmitted only by spike counts. PSTH modulations constitute the crucial component of this code, while correlations between the spikes play a less important (but positive) role. © 2002 Elsevier Science B.V. All rights reserved.