Motor imagery ability in stroke patients with and without neglect: A pilot control case series study

Abstract

Individuals with stroke may experience sensory-motor deficit and/or neglect, with possible reduction in motor imagery ability (MI). To date, no study completely investigated MI ability in the same individual using measures adapted to clinical setting. This study aims to investigate MI ability in stroke patients with or without neglect as compared to aged-matched healthy individuals. We assessed explicit MI (EMI) using 3 questionnaires (Movement Imagery Questionnaire-RS–MIQ-RS, Kinesthetic and Visual Imagery Questionnaire-20–KVIQ-20, Vividness of Movement Imagery Questionnaire-2) and 2 tests (Time Up and Go, Box and Block test), measuring (i) vividness, (ii) electrodermal activity and (iii) temporal equivalence between MI and physical practice (PP). We also assessed implicit MI (IMI) using a hand laterality judgment task, measuring response time and percentage of correct responses. We recruited a total of 12 stroke patients including one patient with neglect (experimental group, EG) and 12 healthy subjects (control group, CG). For EMI, comparison between EG and CG showed no significant decrease in vividness and electrodermal activity but an increase in MI duration regarding PP for both KVIQ and MIQ-RS. For IMI, comparison revealed similar response time but a significant decrease in percentage of correct responses for EG. Interestingly, the patient with neglect exhibited similar IMI performance to the one of other patients but the lowest vividness and the longest MI duration regarding PP for EMI. Stroke patients without neglect have reduced MI ability but seem still able to imagine movements. Conversely, neglect may sharply decrease EMI while sparing IMI. Although further interpretation should be formulated with caution given the small number of patients, one could likely include stroke patients without neglect in MI rehabilitation programs as suggested by other studies, but definitive exclusion from MI programs in case of neglect requires further investigations.