Motor imagery and aging

A Comparison of Movement Imagery Ability Self-Report and Imagery Use in a Motor Task: A Preliminary Investigation

The present study used the Movement Imagery Questionnaire (MIQ-3) to determine the relationship between self-report movement imagery ability and performance on a motor task requiring use of visual and kinesthetic imagery. Young adults were asked to view a number sequence of 4- and 5 digits, maintain the information over a 6 s delay (blank screen) using visual imagery maintenance, and complete the sequence by finger-tapping complementary numbers using motor (kinesthetic) imagery and actually executing movements. We predicted higher movement imagery ability scores would be associated with faster movement times, and imagery ability would be significantly related to the motor tasks. Correlation results indicated no significant differences between self-report and finger-tapping scores, suggesting that in the context of the motor tasks used here, performance was independent of movement imagery ability. Discussion of this preliminary study focuses on the role of visual working memory in the motor task used here and its lack of assessment using the MIQ-3 and other current self-reports.

Motor timing deficits in sequential movements in Parkinson disease are related to action planning: a motor imagery study

Timing of sequential movements is altered in Parkinson disease (PD). Whether timing deficits in internally generated sequential movements in PD depends also on difficulties in motor planning, rather than merely on a defective ability to materially perform the planned movement is still undefined. To unveil this issue, we adopted a modified version of an established test for motor timing, i.e. the synchronization–continuation paradigm, by introducing a motor imagery task. Motor imagery is thought to involve mainly processes of movement preparation, with reduced involvement of end-stage movement execution-related processes. Fourteen patients with PD and twelve matched healthy volunteers were asked to tap in synchrony with a metronome cue (SYNC) and then, when the tone stopped, to keep tapping, trying to maintain the same rhythm (CONT-EXE) or to imagine tapping at the same rhythm, rather than actually performing it (CONT-MI). We tested both a sub-second and a supra-second inter-stimulus interval between the cues. Performance was recorded using a sensor-engineered glove and analyzed measuring the temporal error and the interval reproduction accuracy index. PD patients were less accurate than healthy subjects in the supra-second time reproduction task when performing both continuation tasks (CONT-MI and CONT-EXE), whereas no difference was detected in the synchronization task and on all tasks involving a sub-second interval. Our findings suggest that PD patients exhibit a selective deficit in motor timing for sequential movements that are separated by a supra-second interval and that this deficit may be explained by a defect of motor planning. Further, we propose that difficulties in motor planning are of a sufficient degree of severity in PD to affect also the motor performance in the supra-second time reproduction task.