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Abstract:
Although imagined rotations of objects and body parts have
been recently examined using functional imaging, no studies have
explicitly investigated imagined rotations of the self. Previous
behavioral studies demonstrated that imagined viewer rotations are
easier to perform than imagined object rotations when asked to
spatially update the positions of the objects (Wraga, Creem, &
Proffitt, 1998). The present study explored the neural basis of
imagined viewer rotations using fMRI. Participants memorized the
positions of four objects in an array. Given a degree of rotation
and a position in the array (e.g. "90, what's on the right?"), they
imagined themselves rotating within the stationary array and named
the object corresponding to the given position. The baseline
involved only 0 degree rotations, whereas the task involved 90,
180, and 270 degree rotations. Similar response latencies for all
degrees of rotation greater than zero suggest that participants
easily transported themselves to face a new direction, as found in
previous behavioral studies. Activations were found in both primary
and higher visual areas (areas18,19). In addition, we found
significant activations in both superior and inferior parietal
lobe, areas which are commonly associated with mental rotation
tasks. Furthermore, activation found in middle frontal gyrus
supports previous results implicating premotor areas involved in
imagined body-transformations.
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