This forms a circular process of visual computation, a cognitive decision for the next saccade target, and motor execution 17, 18. Third, natural visual behavior in primates is an intrinsically recurrent process consisting of recursive sampling of the same visual scene with different eye positions, and saccades are the result of ongoing visual processing. Second, recent advances in our understanding of occipital and temporoparietal white matter revealed that communication across the dorsal and ventral visual areas is far richer than previously thought 15, 16. First, functional 8, 9, 10 and anatomical studies 11, 12, 13, 14 have shown that there are many alternative routes that bypass V1, which is often assumed to be the entry point for visual information into the cerebral cortex, such as the extrastriate cortex and temporoparietal regions. However, several recent studies have shed light on a complementary or alternative schema for visual information flow proposed in this theory. The dual-stream hypothesis models how visual information is processed in this circuitry, in which the visual input received by the retina is transmitted to the primary visual cortex (V1) and then flows to the functionally distinct dorsal and ventral visual streams 3, 4, 5 the former is dedicated to the analysis of scenes and object semantics 6, while the latter is important for the analysis of the spatial properties of visual information 7. ![]() More than 30 cortical areas have visual functions and are organized hierarchically into complex feedforward and feedback connections 1, 2. The primate visual system is one of the most investigated cortical circuitries. Overall, this study reveals the neural dynamics of active vision, which are efficiently linked to the natural rhythms of visual exploration. We also demonstrated that saccades could occur at any point of signal flow, indicating the parallel computation of motor commands. ![]() Such signal dynamics occurred at an average of 220 ms after saccades, which corresponded to the timing when whole-brain activation returned to background levels. Similarly, the signal that propagated from the dorsal to ventral visual areas was accompanied by a travelling wave of low frequency oscillations. We found that the dorsal stream was activated before the primary visual cortex with saccades and followed by the alteration of suppression and activation signals along the ventral stream. Here, we report cerebral neural dynamics during active visual exploration recorded by an electrocorticographic array covering the entire lateral surface of the marmoset cortex. Numerous studies have shown that the visual system consists of functionally distinct ventral and dorsal streams however, its exact spatial-temporal dynamics during natural visual behavior remain to be investigated.
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