[Abstract Title]. - Society for Neuroscience

govern more global types of processing are not fully developed until six months of age or older
(e.g., Batardieré et al., (2002) Cerebral Cortex. 12, 453-465). Therefore, if feedback connections
were involved in crowding, one would not expect to see crowding effects in infant macaques.
We tested seven pig-tailed macaque monkeys in three different age ranges: five weeks (infant),
six months (juvenile) and two or more years (adults). To test whether “crowding” is observed
during development, subjects were trained to discriminate a band-limited C-pattern comprised of
Gabor patches in the presence of Gabor patch flankers placed at various distances from the C
along the horizontal axis. This type of stimulus has been used in many human psychophysical
studies of crowding. We found that macaques at all test ages showed a crowding effect. The
“critical distance” or range of crowding was 2.45 standard deviations for the infant, 2.04 for the
juvenile, and 2.58-2.64 for the adults. Our macaque adults perform similarly to humans: critical
distances for two adult humans tested with the same stimuli were 2.26 and 2.44. These data
suggest that crowding is mediated by connections that are already fully developed near birth. Our
results further indicate that macaque monkeys are a useful model for studying lateral spatial
interactions related to object processing, and provide important insight into the neural
mechanisms of crowding.
Disclosures: M.A. Hagan, None; D. Li, None; G. von Trapp, None; L. Kiorpes, None.
Poster
260. Objects and Faces in Humans II
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 260.2/BB14
Topic: D.04.j. Processing of objects and faces
Support: NIMH
Autism Speaks
Title: Improved functional MRI of the macaque ventral visual pathway at 3 T using multi-echo
EPI and dynamic, field map corrected image reconstruction
Authors: *M. A. PINSK 1,2 , M. ARCARO 1,2 , C. S. KONEN 1,2 , X. LI 1,2 , S. KASTNER 3,1,2 , S. J.
INATI 4 ;
1 Dept Psychol, 2 Ctr. for the Study of Brain, Mind & Behavior, 3 Princeton Neurosci. Inst.,
Princeton Univ., Princeton, NJ; 4 Ctr. for Brain Imaging, New York Univ., New York, NY
Abstract: The macaque ventral visual pathway along the temporal lobes has been shown to be
an important region in visual object perception, recognition, and memory (Desimone and