Diversity of computation of orientation and direction preference by visual cortical neurons: An intracellular reexamination
Résumé
Brain computation, in the early visual system, is often considered as a hierarchical process where features extracted in a given sensory relay are not present in previous stages of integration. In particular, many response properties in the primary visual cortex, such as orientation and directional selectivity, are not present at the preceding geniculate stage, and a classical problem is identifying the mechanisms and circuitry underlying these computations. Two main organization principles have been proposed: either the functional properties of cortical cells are defined by the feedforward drive, or they are shaped by intracortical excitatory and inhibitory architecture.