Abstract
Recent experimental evidence (Neely & Heath, 2010) suggests that visuomotor mental rotation does not rely on a rotation process that occurs just prior to response initiation, but instead relies on a more complex and cognitive substitution process related to the sensorimotor transformations mediating the response. Here, we sought to provide further evidence for this contention by using event-related brain potentials (ERP) to demonstrate that an increase in the degree of visuomotor mental rotation resulted in a related increase in the amplitude of the P300 – an ERP component that has an amplitude sensitive to the magnitude of cognitive processing. Our behavioral results are in line with previous work – the amount of spherical variability in movement endpoints increased in relation to increases in the degree of visuomotor mental rotation. Not surprisingly, our ERP data revealed differences in visual processing between the presentation of unrotated and rotated targets. However, as predicted, the amplitude of the P300 scaled to the degree of visuomotor mental rotation – a result that supports the Neely and Heath's findings and suggests that visuomotor mental rotation relies on a cognitive response substitution process as opposed to a rotation of the movement vector just prior to movement onset.
