Feedforward and feedback connections between areas V1 and V2 of the monkey have similar rapid conduction velocities.

Neurophysiol P . Girard , J . M . Hupé and J . Bullier Conduction Velocities V 1 and V 2 of the Monkey Have Similar Rapid Feedforward and Feedback Connections Between Areas

Feedback connections from area MT of the squirrel monkey to areas V1 and V2.

Area MT/V5 is reciprocally connected with both V1 and V2; but, despite extensive anatomical and physiological investigations, detailed information on the feedback component of these connections is still not available. The present report uses serial section reconstruction of single axons, labeled by anterograde tracers injected in area MT of squirrel monkeys, to characterize these connections fu...

Self-organization of hierarchical visual maps with feedback connections

Visual areas in primates are known to have reciprocal connections. While the feedforward bottom-up processing of visual information has been studied extensively for decades, little is known about the role of the feedback connections. Existing feedback models usually employ hand-coded connections, and do not address how these connections develop. The model described in this paper shows how feedf...

Retinotopic axis specificity and selective clustering of feedback projections from V2 to V1 in the owl monkey.

Cortical maps and feedback connections are ubiquitous features of the visual cerebral cortex. The role of the feedback connections, however, is unclear. This study was aimed at revealing possible organizational relationships between the feedback projections from area V2 and the functional maps of orientation and retinotopy in area V1. Optical imaging of intrinsic signals was combined with cytoc...

A Neurodynamical Theory of Visual Attention: Comparisons with fMRI- and Single-Neuron Data

We describe a model of invariant visual object recognition in the brain that incorporates different brain areas of the dorsal or ‘where’ and ventral or ‘what’ paths of the visual cortex. The dorsal ‘where’ path is implemented in the model by feedforward and feedback connections between brain areas V1, V2 and a PP module. The ventral ‘what’ path is implemented in a physiologically plausible four...