[Abstract Title]. - Society for Neuroscience

about non-preferred objects. We tested the specificity of the occipital face area (OFA), the
extrastriate body area (EBA), and lateral occipital area (LO) in the right hemisphere by
delivering TMS during discrimination tasks involving faces, bodies, and novel objects. Target
areas were individually localized using fMRI in fifteen subjects who were then tested in three
separate TMS experiments. Each experiment compared performance on same-different matching
tasks from two object classes while TMS was delivered over the cortical areas selective for those
classes (e.g. face and object tasks with TMS over OFA and LO). Participants also performed
each task without TMS to act as a behavioral baseline. All three experiments showed a double
dissociation with task performance impaired only on the site selective for that object class.
Namely, TMS over OFA impaired discrimination of faces but not objects or bodies; TMS over
LO impaired discrimination of objects but not faces or bodies; TMS over EBA impaired
discrimination of bodies but not faces or objects. These results indicate that recognition of items
from each category relies on representations in the respective category-selective areas and not on
a more distributed representation.
Disclosures: D.J. Pitcher , None; L. Charles, None; J. Devlin, None; V. Walsh, None; B.
Duchaine, None.
Poster
260. Objects and Faces in Humans II
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 260.18/BB30
Topic: D.04.j. Processing of objects and faces
Support: CIHR
Title: Cue-integration and competition between shading and structure-from-motion
Authors: *R. FARIVAR-MOHSENI, A. CHAUDHURI;
Dept. of Psychology, McGill Univ., Montreal, QC, Canada
Abstract: Natural vision requires integration of several co-localized depth cues, such as shading,
stereopsis, and structure-from-motion. Typically, experiments investigating cue combinations
have utilized an additive or subtractive approach, by adding or removing additional depth cues
from the structure of an object. Here we investigated the possibility that different cues may
integrate across space in order to drive a coherent percept. If cue-chimeria is resolved prior to
processes of object recognition, then illusory effects seen in object recognition, such as the
composite face effect, should be unaffected by cue-chimeric stimuli. If, on the other hand,
different cues give rise to separate object descriptors, then the composite face effect should