Use of mental imagery to improve task generalisation after a stroke

Stroke rehabilitation aims to help people regain lost functions and reintegrate into the community. Previous studies have reported the positive effects of mental imagery (MI) on learning. Mental imagery involves memory retrieval, and the generation and maintenance of images. It is believed that generating the image, 'seeing the performance of the behaviour with the mind's eye', prior to performance of the task, activates neural substrates that are subsequently involved in the actual performance of the task. This effect is thought to facilitate the planning and execution of the task, thereby increasing the level of independent task performance. Mental imagery has been applied to stroke rehabilitation to promote upper limb motor function and visual neglect. Our previous randomised controlled trial indicated that patients receiving 3 weeks of MI intervention performed daily tasks better than those receiving conventional rehabilitation. These findings demonstrated that MI could enhance the relearning of lost functions, possibly via active control of the task performance. Generalisation demands that a person modify, assimilate and apply the skills learned in one environment to fit another environment. In the context of rehabilitation for people with brain injuries, the skills learned in hospital after a brain injury need to be generalised to a different environment. The extent to which skills learned in the hospital environment are generalised to the home environment contributes to the success with which the person reintegrates into the community and is able to lead a normal life. This study investigated the benefits of an MI intervention to enhance performance of tasks in a novel environment for post-stroke patients. A randomised clinical trial was used to compare the generalisation of daily task performance across different environments using an MI intervention and a functional rehabilitation (FR) programme.