INT'L GUEST SPEAKER- Professor Stefan Treue PhD, Cognitive Neuroscience Laboratory, German Primate Center, Göttingen: ‘Visual cortical area V5/MT - a prototype for shaping sensation into perception’

Area V5/MT in primate visual cortex is arguably the best understood area in primate extrastriate visual cortex in terms of its representation of the incoming (bottom-up) sensory information. MT is considered to be of critical importance for our ability to perceive the visual motion patterns in our environment.

This level of understanding of the neural representation of sensory information in one cortical area is an excellent basis for investigating the top-down influences exerted by various types of attention onto sensory information processing.

The talk will give an overview of the multitude of attentional effects that have been discovered with this focused approach, ranging from effects of spatial, feature-based and object-based attention on target and distractor stimuli encoding to multiplicative and non-multiplicative modulations of tuning curves, perisaccadic effects, as well as effects on the representation of change events in the environment and neural responses that are not modulated by attention.
From these investigations a clear pattern emerges that turns MT into a model area for the interaction of sensory (bottom-up) signals with cognitive (top-down) modulatory influences that characterises visual perception. These findings also document how this interaction enables visual cortex to actively generate a neural representation of the environment that combines the high-performance sensory periphery with selective modulatory influences for producing an “integrated saliency map’ of the environment.