At what time scale does the nervous system operate?

A novel statistical strategy, the spike jitter method, was developed to assess temporal structure in spike trains from neuronal ensembles. Its keyfeature is the introduction of a null hy pothesis that assumes a uniform relative likelihood of observing a spike at one temporal location versus another within a small temporal window. We applied the method to simultaneouslyrecorded motor cortical neurons in behaving monkeys and examined the occurrence of /nely timed synchronybetween neuron pairs. Evidence was found for millisecond sy nchronythat could onlybe accounted for byassuming /ne temporal structure in the constituent neurons’ spike trains. The method was also applied to higher-order patterns. c 2002 Elsevier Science B.V. All rights reserved.