Nature Neuroscience
4, 194 - 200 (2001)
doi:10.1038/84032
Rapid feature selective neuronal synchronization through correlated latency shiftingPascal Fries1, 2, 3, Sergio Neuenschwander1, Andreas K. Engel1, 4, Rainer Goebel1, 5
& Wolf Singer11
Max-Planck Institute for Brain Research, Deutshcordenstra e 46, 60528 Frankfurt am Main, Germany
2
Johann Wolfgang Goethe-University, Department of Psychiatry, Heinrich-Hoffmann Strae 10, 60528 Frankfurt am Main, Germany
3
Present address: Laboratory of Neuropsychology, National Institute of Mental Health, Building 49, 49 Convent Drive, MSC 4415, Bethesda, Maryland 20892, USA
4
Present address: Research Centre Juelich, Institute for Medicine, Cellular Neurobiology Group, 52425 Juelich, Germany
5
Present address: University of Maastricht, Neurocognition Group, Department of Psychology, Postbus 616, 6200 MD Maastricht, The Netherlands
Correspondence should be addressed to Wolf Singer singer@mpih-frankfurt.mpg.deSpontaneous brain activity could affect processing if it were structured, . We show that neuron pairs in cat primary visual cortex exhibited correlated fluctuations in response latency, particularly when they had overlapping receptive fields or similar orientation preferences. Correlations occurred within and across hemispheres, but only when local field potentials (LFPs) oscillated in the gamma-frequency range (40−70 Hz). In this range, LFP fluctuations preceding response onset predicted response latencies; negative (positive) LFPs were associated with early (late) responses. Oscillations below 10 Hz caused covariations in response amplitude, but exhibited no columnar selectivity or coordinating effect on latencies. Thus, during high gamma activity, spontaneous activity exhibits distinct, column-specific correlation patterns. Consequently, cortical cells undergo coherent fluctuations in excitability that enhance temporal coherence of responses to contours that are spatially contiguous or have similar orientation. Because synchronized responses are more likely than dispersed responses to undergo rapid and joint processing, spontaneous activity may be important in early visual processes.
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