Crossmodal double dissociations between ‘what’ and ‘where’
Poster

Jason Chan
Trinity College Dublin

Fiona Newell
Trinity College Dublin

     Abstract ID Number: 100
     Full text: Not available
     Last modified: May 20, 2003

Abstract
The double dissociation effect is used to demonstrated the modularity of the brain, and its effect on behaviour. This double dissociation method has typically been used within one modality. Tresch, Sinnamon & Seamon (1993) found evidence that form recognition and object location tasks are dissociated in visual memory. Thus they found behavioural evidence for two independent (“what” and “where”) visual streams. Using this approach we investigated whether object form and location tasks are independent across visual and haptic modalities. In Experiment 1, participants were required to conduct an object form or location matching primary task. Between stimulus presentations, participants were also required to conduct a secondary form or location task but in the modality other than that used for the primary task. In Experiment 2, the secondary task was always within-modal. We reasoned that if the same mechanisms are used for visual and haptic form or location matching, then we would expect cross modal interference for the same primary and secondary tasks, but not with different tasks. We found no evidence for cross-modal double dissociations. This may be because of crossmodal perceptual load. Our findings will be discussed in terms of multisensory, task-independent processing of form and location.