The motor-cognitive model of motor imagery: Evidence from timing errors in simulated reaching and grasping.

Abstract

Motor imagery represents an important but theoretically underdeveloped area of research in psychology. The motor-cognitive model of motor imagery was presented, and contrasted with the currently prevalent view, the functional equivalence model. In 3 experiments, the predictions of the two models were pitted against each other through manipulations of task precision and the introduction of an interference task, while comparing their effects on overt actions and motor imagery. In Experiments 1a and 1b, the motor-cognitive model predicted an effect of precision whereby motor imagery would overestimate simulated movement times when a grasping action involved a high level of precision; this prediction was upheld. In Experiment 2, the motor-cognitive model predicted that an interference task would slow motor imagery to a much greater extent than it would overt actions; this prediction was also upheld. Experiment 3 showed that the effects observed in the previous experiments could not be due to failures to match the motor imagery and overt action tasks. None of the above results were explainable by either a strong version of the functional equivalence model, or any reasonable adaptations thereof. It was concluded that the motor-cognitive model may represent a theoretically viable advance in the understanding of motor imagery. (PsycINFO Database Record

Executive functions in motor imagery: support for the motor-cognitive model over the functional equivalence model

“…The traditional view of motor imagery holds that it operates using the same internal mechanisms as overt action (Decety 1996;Holmes and Collins 2001;Jeannerod 1994Jeannerod , 2001. However, whereas motor imagery often mimics the behavioural outcomes of overt actions (Decety and Michel 1989;Decety and Jeannerod 1995;Dixon and Glover 2009;Glover and Dixon 2013;), numerous discrepancies have been observed in both the behavioural outputs (Calmels and Fournier 2001;Ceretelli et al 2000;Coelho et al 2012;Glover and Baran 2017;Slifkin 2008;Walsh and Rosenbaum 2009) and neural correlates (Gerardin et al 2000;Hetu et al 2013;Guillot et al 2009;Nair et al 2003) of imagined versus overt actions. Elucidating and accounting for the differences as well as the similarities between these two behaviours is of critical importance in the understanding of both.…”

“…The motor-cognitive model holds that the planning of both motor imagery and overt action rely on shared motor representations; during execution the two behaviours are subserved by different mental processes (Glover and Baran 2017). Whereas overt actions use visual and proprioceptive feedback to monitor and correct ongoing movements, these sources of information are unavailable to motor imagery due to the lack of physical movement.…”

“…Communicated by Carlo Alberto Marzi. It is this functional bifurcation of motor imagery and overt actions during execution that leads to differences in their behavioural outputs under many circumstances. When an imagined action's overt counterpart relies heavily on online control, or when the executive functions used during motor imagery are otherwise engaged, the performance of motor imagery is slowed relative to overt action (Glover and Baran 2017;Calmels et al 2006).…”

“…The functional equivalence view thus predicts a close match in both the behavioural characteristics and neural activation patterns of motor imagery and overt action. Glover and Baran (2017) presented evidence for the motor-cognitive model and against the functional equivalence model. We showed that motor imagery was slowed more by tasks that emphasised online control, and by interference tasks that depleted executive resources, than was overt action.…”

“…Despite the findings of minimal effects of an interference task on overt actions observed by Glover and Baran (2017), there is evidence that overt actions can also be affected by interfering with executive functions (see Leone et al 2017, for a review). For example, a classic study by Creem and Profitt (2001) demonstrated that a semantic interference task affected the choice of postures in grasping everyday tools.…”