Evaluating a New Verbal Working Memory-balance Program: a Double-blind, Randomized Controlled Trial Study on Iranian Children With Dyslexia

Abstract

\n Background: It is important to improve verbal Working Memory (WM) in reading disability, as it is a key factor in learning. There are commercial verbal WM training programs, which have some short-term effects only on the verbal WM capacity, not reading. However, because of some weaknesses in current verbal WM training programs, researchers suggested designing and developing newly structured programs that particularly target educational functions such as reading skills. In the current double-blind randomized clinical trial study, we have designed a new Verbal Working Memory-Balance (VWM-B) program, and a portable robotic device was adopted and developed to perform the program. The short-term effects of the VWM-B program on verbal WM capacity, reading skills, and postural control were investigated in Iranian children with Developmental Dyslexia (DD).Results: In the present study, 29 children with DD, 7 to 10 years old, were randomly assigned to control and intervention groups. Both groups received five weeks of training by the VWM- program (as a traditional verbal WM training) and VWM-B program, respectively. A separate 2×2 mixed ANOVA, with a between-subjects factor group and within-subjects factor time , was used to verify the main effects of the training programs on the measured functions. The time×group interaction was significant for outcomes of the verbal WM, reading skills, and postural control.Conclusions: The VWM-B program was found to be more effective than the VWM-program in the improvement of functions. We proposed that the automatized postural control resulting from VWM-B training probably had a positive impact on improving measured cognitive functions. Based on the critical role of the cerebellum in automatizing skills, our findings support the cerebellar deficit theory in dyslexia.Trial registration: This trial was (retrospectively) registered on 8 February 2018 with the Iranian Registry of Clinical Trials (IRCT20171219037953N1).