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Abstract:
Abstract: Recent evidence suggests that motor areas are
activated in some types of mental rotation (e.g., Wexler, Kosslyn ,
& Berthoz, 1998). The current study examined whether explicit
instruction can activate motor processes during mental rotation of
objects. Participants viewed pictures of two misoriented
Shepard-Metzler objects, and decided whether the objects were
identical by used different strategies to imagine rotating one
object into congruence with the other. In the External condition,
participants imagined rotating the objects as if by an externally
driven motor. In the Internal condition, they imagined rotating the
objects with their dominant hand. Activation was compared to a
baseline condition in which identical comparisons were made without
rotation. The principal finding was that the Internal task
activated primary motor cortex (BA 4) in the hemisphere
contralateral to imagined hand movement, whereas the External task
did not activate BA 4. Other areas of activation included the
parahippocampal gyrus (BA 36) and the junction between inferior and
superior parietal lobules (BA 40/7) in the Internal task; and the
junction between the orbitalfrontal and inferior frontal gyri (BA
11/47) in the External task. The main findings suggest that
motor-based strategies can be used to mentally rotate objects.
Moreover, they reflect a flexibility within the human cognitive
system for implementing multiple rotation processes.
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