Treating Metaphor Interpretation Deficits Subsequent to Right Hemisphere Brain Damage: Preliminary Results

PURPOSE: This investigation sought to determine whether a structured intervention focused on improving use of semantic associations could improve patients' ability to provide oral interpretations of metaphors following Right Hemisphere Damage (RHD). METHODS: Principles of single subject experimental design provided the basis for the study. Five patients received either 10 or 20 baseline assessments of oral metaphor interpretation and, as a control, assessments of line orientation skill. They then received approximately 10 one-hour sessions of structured intervention to improve oral metaphor interpretation followed by post-training assessments and a 3 month follow up. RESULTS: Patients' performances revealed evidence of good response to training as shown by patients' ability to reach criterion on all intervention tasks and by their significant improvement on oral metaphor interpretation. There was relatively little improvement on the line orientation task. DISCUSSION: The results of this study support the clinical usefulness of this new approach to treating communication deficits associated with RHD due to stroke, even years post-onset. There are, however, questions that remain unanswered. For example, additional data will be needed to gauge how a patient's severity of impairment relates to the potential for improvement, to chart the durability and scope of improvement associated with the training, and to determine the type of visuospatial ability needed for using this type of pictorial material.