The Effects of Physical Practice on a Novel Mental Imagery Task as Measured by Electroencephalography (EEG)

Studies have shown that the use of mental imagery can improve performance (Mamassis & Doganis, 2004; Martin, Mortitz, & Hall, 1999). However, these studies only use outcome measures to show the benefits of mental imagery/practice. Researchers have not yet examined the underlying cognitive processes of imagery performance as individuals physically learn a new skill. The purpose of this study was to determine the effects of physical practice on EEG activity when imagining a dart throwing task. EEG activity from P4, P3, O2, and O1 was recorded from 30 volunteers. Participants were randomly assigned to either a physical practice condition or a non-practice condition. Ten two-second epochs were recorded and analyzed for both the pre-test and post-test. A separate 2 x 2 x 2 x 2 (Hemisphere x Sites x Test x Practice) mixed model design was conducted for each EEG frequency band (i.e., lower alpha, upper alpha, lower beta, and upper beta). Results revealed a significant interaction test by practice in the lower alpha band (p > .05). Further, there was a significant interaction test by site (p < .05) in the lower alpha band. Lastly, a significant interaction site by hemisphere was shown in the lower beta band (p < .05). The results suggest that either the task was not complex enough to detect differences or the participants did not have adequate physical practice. In addition, the occipital sites were less involved in attention and effort during the post-test imagery performance while the parietal sites were as involved as the pre-test. The imagery script used for this study emphasized feeling the movement prior to imagery performance, and this may have resulted in the parietal region being activated during the pre- and post-test. However, the occipital region at the left hemisphere was more stimulated than the right hemisphere, suggesting the cognitive processing of imagery instructions.