Authors:

CUSACK, R. & CARLYON, R.P.

Reference:

Year of publication:

2004

CBU number:

5873

Abstract:

Often, the sound arriving at the ears is a mixture from many different sources but we are only interested in one. The auditory system structures the vast array of incoming sensory information into streams, from amongst which we can then select. Here, we present research investigating three aspects of stream segregation and selective attention. In the first, we showed that stream segregation is strongly mediated by attention. We further characterised the interaction between these two processes, and propose a "hierarchical decomposition" model that is consistent with the data. Second, we investigated the neural basis of stream segregation using fMRI. We found that the activation of the intraparietal sulcus correlates with stream segregation, independently of physical differences between stimuli. We suggest that it may play a general role in structuring sensory information. Third, we show that the way in which features are coded in the auditory system strongly affects listeners' ability to select targets amongst distractors. We found marked search asymmetries, analogous to those observed in visual search experiments.