Visuomotor mental rotation: reaction time is determined by the complexity of the sensorimotor transformations mediating the response.

摘要

In the visuomotor mental rotation (VMR) task, participants point to a location that deviates from a visual target by a predetermined angle. A seminal investigation of the VMR task reported a linear increase in reaction time (RT) as a function of increasing angle, for 5 degrees , 10 degrees , 15 degrees , 35 degrees , 70 degrees , 105 degrees , and 140 degrees (Georgopoulos and Massey, 1987). This finding led to the development of the mental rotation model (MRM) and the assertion that response preparation is mediated via the imagined rotation of a movement vector. To determine if the MRM can be extrapolated to perceptually familiar angles (e.g., 90 degrees and 180 degrees ) within a range of equally spaced angles, we evaluated two independent sets of angles: 5 degrees , 10 degrees , 15 degrees , 35 degrees , 70 degrees , 105 degrees , and 140 degrees (experiment one) and 30 degrees , 60 degrees , 90 degrees , 120 degrees , 150 degrees , 180 degrees , and 210 degrees (experiment two). Consistent with the MRM, experiment one revealed a linear increase in RT as a function of increasing angle; however, a non-linear relation was revealed for experiment two. RTs were fastest for 180 degrees , followed by 30 degrees , 90 degrees , 60 degrees , 150 degrees , 210 degrees , and 120 degrees . Such results demonstrate that response preparation was not uniquely mediated via a mental rotation process. Instead, the present work provides evidence of a temporally demanding and cognitively mediated response substitution process, wherein the computational demands of response preparation are determined by the complexity of the sensorimotor transformations mediating the response.