Tuesday, August 9, 2011

The efficacy of Visualising and Verbalising: are we asking too much?

Dixon, G., Joffe, B., & Bench, R. J. (2001). The efficacy of Visualising and Verbalising: are we asking too much? Child Language Teaching and Therapy, 17(2), 127-141.

The purpose of the current study was to investigate treatment approaches for the remediation of language comprehension difficulties in children. In the study, Dixon et al. compare the approaches of Visualising and Verbalising and Traditional comprehension training in language impaired (LI) children. Traditional comprehension training teaches skills such as finding the main idea, following sequences, and inference understanding and creation. The Visualising and Verbalising training consists of several stages in which students are first taught descriptive vocabulary, followed by sentence visualization and verbalization exercises. The main difference between the approaches is the encouragement of visualization in the latter approach, and the absence of this type of encouragement in the former approach.

Eight children with language impairment between the ages of 9;0 and 15;1 completed 10 weeks of therapy sessions that were distributed into three therapy conditions: Visualising and Verbalising only, Traditional and Visualising and Verbalising (5 weeks of each type), and Traditional only.

Results showed that the children’s comprehension ability (as measured using the Analytical Reading Inventory) improved over the course of the study, regardless of the treatment approach. Critically, through a covariance analysis between the two types of approaches, the Visualising and Verbalising group did not improve significantly more than the Traditional group. These results suggest that the use of mental imagery does not appear to aid in narrative comprehension.

Dixon et al. suggest that the simultaneous maintenance of a mental image (visualizing) with the cross-modal auditory processing of incoming information (verbalizing) may have exceeded LI children’s working memory capacity, thereby not conferring the expected benefit. However, it should be noted that none of the children in the Visualising and Verbalising condition actually completed the full program as it was originally described. As well, this study did not take into account the working memory abilities of the children. Nevertheless, this study raises some concern that the clinical assumption that visualizing will aid verbalization may not always be a valid assumption.

Blogger: Jackson Wilson