Recent Findings

  • Changes in the brain as mental representations become more complex ? (link to pdf)   Funded by a Royal Society International Outgoing Short Visit award, brain imaging (fMRI) technology was used to identify neural areas that become active when the complexity of a mental representations increase.  This study used a well understood task – searching for a visual target in a cluttered display. We successfully separated out the phase of ‘preparing to search’ for a visual target and the actual ‘search phase’. This enabled us to see how the brain prepares to search for a simple compared to a more complex target.
  • Complexity of mental representations and general limits on attention. Previously we demonstrated that there is a general limit on how much we can attend to (link to pdf). Part of our on-going programme of research is to understand the types of task that place a heavy demand on this ‘general attention system’. Our results show that as the complexity of a representation increases, in a visual search task, the greater is the interference with a concurrent task. In contrast, manipulating other aspects of the visual task which increases reaction time causes no interference with the concurrent task (link to pdf).
  • Enhanced awareness of the space around the hands. We have an enhanced awareness of the space around our bodies. This is known to encompass the space between us and where we are currently looking. Recently we have shown that this enhanced awareness can extend beyond this to wherever our hands are, but only if we are preparing to make a movement. (link to pdf)
  • Does the brain represent the world in 3D space? Very early vision is guided as to where to look, by non-conscious processes such as ‘Inhibition of Return’.  At this early stage, does the brain represent the world in 3D space? We have been able to answer this by using stimuli positioned at different depths. We have concluded that ‘object based IOR’ operates on 3D object representations, perhaps part of a reaching system. Whereas ‘space based IOR’ operates on 2D representations, part perhaps of a saccadic eye movement system (link to pdf)