Ingo Fründ, "Speed in early visual processing", 2007.

The visual system of vertebrates rapidly provides a basis for execution of behavioral responses (Kirchner & Thorpe, 2006). At the same time it is up to amazingly detailed representations of the environment and even learning of these representations. Different investigators have proposed mechanisms how a network of neurons could achieve either the speed (see Thorpe et al., 2001) or the analytic capability (e.g. Freeman, 2003; König & Krüger, 2006; Thielscher & Neumann, 2006) of the visual system. The experiments in this report will focus on this discrepancy and investigate coding in the visual system with special focus on oscillations as control signals of neuronal processing. The results do not conclusively support either spike based coding (Thorpe et al., 2001; Körner et al., 1999) or distributed rate coding (Rolls et al., 1997; Freeman, 2003). These two positions are, however, not mutually exclusive. While the individual neural spikes make up a distributed firing rate, it is by means of the dense interconnections between neurons, that this population firing rate determines the timing of spikes from individual neurons (e.g. Haken, 1983). It might however be, that the information contained in the spike timings is optimal for different aspects of behaviour than is the information contained in spike rates (Fründ & Herrmann, 2007). The data presented in this report about phase-locking of evoked GBRs seem to indicate that temporal reorganization of spontaneous brain activity is crucial for linking perceptual and behavioral processing.