RT Journal Article
SR Electronic
T1 The Relationship between Task Performance and Functional Magnetic Resonance Imaging Response
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 3023
OP 3031
DO 10.1523/JNEUROSCI.4476-04.2005
VO 25
IS 12
A1 Giedrius T. Buracas
A1 Ione Fine
A1 Geoffrey M. Boynton
YR 2005
UL http://www.jneurosci.org/content/25/12/3023.abstract
AB We compared psychophysical and functional magnetic resonance imaging (fMRI) responses within areas V1-V3 and MT+ during both a speed and a contrast discrimination task. We found that fMRI responses did not depend significantly on task in any of these areas. Moreover, responses in V1-V3 were larger than those in MT+ for both the speed and the contrast discrimination tasks across a wide range of contrasts. This pattern of results demonstrates that localizing function based on finding those regions of cortex that show greater activity to a given task-stimulus combination than to other tasks and stimuli may, under certain conditions, be misleading. However, a simple ideal observer model assuming that perceptual thresholds are dependent on neuronal population responses does successfully show that V1 has neuronal properties consistent with our subjects' contrast discrimination performance, and that MT+ has neuronal properties consistent with subjects' performance on a speed discrimination task.