How the brain selects visual features
Many studies of visual perception and attention suggest that even when focusing on one feature, attention inadvertently reverts to the complete object and its entire set of features. For example, when watching football, the point of interest is the direction in which one's favourite player is moving. However, attention can unintentionally move to other features, such as the colour of a player's shirt. The EU-funded research project 'Revealing the neural mechanisms of attentional selection in the human visual cortex' (VISUAL ATTENTION) studied the neural mechanisms of selective attention taking advantage of behavioural, theoretical and neuroimaging techniques together with novel decoding methods. Scientists set out to determine how cortical selectivity for visual features is modulated by top-down or goal-driven attention. Results indicated that top-down attention can selectively enhance the processing of a single task-relevant feature, such as direction of motion, and that attention does not have to spread to task-irrelevant features. Further, the effect of attention on neural responses seems to depend on the type of attention being used. The research also shows that extensive training on a perceptual task can refine the neural representation of behaviourally relevant information. In particular, visual attention may play a critical role in mediating the effect of training. These results provide important new insights into the neural basis of selective attention. They have significant implications for theories of visual attention and cortical visual function. VISUAL ATTENTION outcomes have revealed important neural mechanisms of visual sensory processing and the ways in which attention modulates them. Aside from basic scientific interest regarding how the brain works, such studies are of key interest and practical use to advertising agencies and manufacturers, video game developers and producers of educational media.
Keywords
Attention, perception, neural mechanisms, attentional selection, visual cortex
