Visual area V4 is not tuned for complex objects such as faces, as areas in the inferotemporal cortex are. The firing properties of V4 were first described by Semir Zeki in the late 1970s, who also named the area.
V6 is a subdivision of the visual cortex of primates first described by John Allman and Jon Kaas in 1975.
Work in the early 1980s proved that V4 was as directly involved in form recognition as earlier cortical areas.
This research supported the two-streams hypothesis, first presented by Ungerleider and Mishkin in 1982. Recent work has shown that V4 exhibits long-term plasticity, encodes stimulus salience, is gated by signals coming from the frontal eye fields, and shows changes in the spatial profile of its receptive fields with attention. == Middle temporal visual area (V5) == The middle temporal visual area (MT or V5) is a region of extrastriate visual cortex.
The mathematical modeling of this function has been compared to Gabor transforms. Later in time (after 100 ms), neurons in V1 are also sensitive to the more global organisation of the scene (Lamme & Roelfsema, 2000).
While feedforward connections are mainly driving, feedback connections are mostly modulatory in their effects (Angelucci et al., 2003; Hupe et al., 2001).
While feedforward connections are mainly driving, feedback connections are mostly modulatory in their effects (Angelucci et al., 2003; Hupe et al., 2001).
Evidence shows that feedback originating in higher-level areas such as V4, IT, or MT, with bigger and more complex receptive fields, can modify and shape V1 responses, accounting for contextual or extra-classical receptive field effects (Guo et al., 2007; Huang et al., 2007; Sillito et al., 2006). The visual information relayed to V1 is not coded in terms of spatial (or optical) imagery but rather are better described as edge detection.
Neurons in area DM respond to coherent motion of large patterns covering extensive portions of the visual field (Lui and collaborators, 2006). Ventral V3 (VP), has much weaker connections from the primary visual area, and stronger connections with the inferior temporal cortex.
Evidence shows that feedback originating in higher-level areas such as V4, IT, or MT, with bigger and more complex receptive fields, can modify and shape V1 responses, accounting for contextual or extra-classical receptive field effects (Guo et al., 2007; Huang et al., 2007; Sillito et al., 2006). The visual information relayed to V1 is not coded in terms of spatial (or optical) imagery but rather are better described as edge detection.
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