We measured the variability in latency of the first spike seen in cells of the cat's lateral geniculate nucleus following the onset of a visual stimulus. We found that, in each of the 11 cells tested, this variability was significantly lower during burst than during tonic firing. We suggest that this difference confers an advantage in signal detection during burst compared to tonic firing. This complements other reported advantages of burst firing for signal detection seen in signal-to-noise ratios and in the ability to efficiently drive postsynaptic cells.