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<div align="center"><font size=4><b>The UCSD Department of Cognitive
Science is pleased to announce a talk by<br><br>
</font><font size=6>Ayse Saygin Ph.D.<br><br>
</font><font size=4>Institute of Cognitive Neuroscience and Wellcome
Trust Centre for<br>
Neuroimaging, University College London<br><br>
<br>
</font><font face="arial" size=4>Friday, February 22, 2008 at 12pm<br>
Cognitive Science Building, room 003<br><br>
<br>
</font><font size=5>"Brain Networks for High Level Visual
Perception: Neuropsychological and Neuroimaging Studies"<br><br>
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How does the brain process meaningful, biologically relevant
stimuli? My research addresses this question using multiple,
complementary methods and subject populations, and a wide range of
stimuli. Here, I will focus specifically on visual perception. First, I
will present experiments where we explored brain areas that subserve the
perception of point-light biological motion. These stimuli consist of
only a handful of moving points, yet lead to a vivid percept of a body
carrying out recognizable actions. Neuroimaging allowed us to identify a
network of brain areas that are involved in processing these stimuli,
while lesion analyses of brain-injured patients corroborated these
findings by identifying the same network as necessary for intact
functioning of the system. Second, using fMRI, we studied retinotopic
maps in the human brain and explored their functional properties.
While retinotopy is a fundamental property of early visual areas, there
are also well-defined retinotopic maps in areas that are not
traditionally thought to be visual. Furthermore, these maps are actively
used in processes such as directing and maintaining attention, as well as
for representing unattended salient stimuli. Overall, this research
provides substantial evidence that even in "passive" perceptual
situations, the brain draws upon sensory, attentional and motor networks
to make sense of complex, meaningful, biologically significant</b>
<b>stimuli.<br><br>
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