Receptive fields (RFs) of neurons within the primate visual system have been reported to shift prior to saccadic eye movements. It has been widely assumed that these presaccadic RF shifts anticipate the actual retinal displacements caused by eye movements in order to stabilize vision. In contrast to this predictive remapping of RFs we recently demonstrated that RFs based on the spiking activity of frontal eye field (FEF) neurons of the macaque monkey converge massively toward the saccadic end point. Here, we investigate the presaccadic RFs derived from simultaneously recorded local field potentials (LFPs) within the FEF. LFPs reflect multiple neuronal processes including extracellular voltage fluctuations due to synaptic inputs and thus carry additional information over that of spiking activity. We quantified LFP-RFs in four different frequency bands, alpha (8-12 Hz), beta (16-30Hz), gamma (30-80 Hz), and high gamma (80-150 Hz). We obtained clear RFs only for the alpha and high gamma bands. Similar to the RFs derived from spiking activity, LFP-RFs in the alpha and high gamma bands were retinocentric during periods of fixation; that is, they remained fixed relative to the fovea across different eye positions. However, shortly before eye movements, LFP-RFs in the high gamma band shifted substantially. Similar to the spiking RFs, the global pattern of the high gamma band LFP-RF shifts consisted of a convergence toward the saccadic end point. In contrast, LFP-RFs in the alpha band showed no consistent shift before eye movements. Thus, LFP-RFs in the alpha and high gamma bands are presaccadically dissociated from one another. The convergence of LFP-RFs in the high gamma band is consistent with local processes contributing to the convergence of spiking activity based RFs.
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