RT Journal Article
SR Electronic
T1 A Distributed Cortical Representation Underlies Crossmodal Object Recognition in Rats
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 6253
OP 6261
DO 10.1523/JNEUROSCI.6073-09.2010
VO 30
IS 18
A1 Boyer D. Winters
A1 James M. Reid
YR 2010
UL http://www.jneurosci.org/content/30/18/6253.abstract
AB The mechanisms by which the brain integrates the unimodal sensory features of an object into a comprehensive multimodal object representation are poorly understood. We have recently developed a procedure for assessing crossmodal object recognition (CMOR) and object feature binding in rats using a modification of the spontaneous object recognition (SOR) paradigm. Here we show for the first time that rats are capable of spontaneous crossmodal object recognition when they are asked to recognize a visually presented object having previously only explored the tactile features of that object. Moreover, rats with bilateral perirhinal cortex (PRh) lesions were impaired on the CMOR task and a visual-only, but not a tactile-only, version of SOR. Conversely, rats with bilateral posterior parietal cortex (PPC) lesions were impaired on the CMOR and tactile-only tasks but not the visual-only task. Finally, crossmodal object recognition ability was severely and selectively impaired in rats with unilateral lesions made to PRh and PPC in opposite hemispheres. Thus, spontaneous tactile-to-visual crossmodal object recognition in rats relies on an object representation that requires functional interaction between PRh and PPC, which appear to mediate the visual and tactile information-processing demands of the task, respectively. These results imply that, at least under certain conditions, the separate sensory features of an object are represented in a distributed manner in the cortex. The novel paradigm introduced here should be a valuable tool for further study of the neurobiological bases of crossmodal cognition and object feature binding.