Self-regulatory speech has been shown to be important for the planning and problem solving of children. Our intervention study, including comparisons to both wait-list and typically developing controls, examined the effectiveness of a training programme designed to improve self-regulatory speech, and consequently, the planning and problem solving performance of 87 (60 males, 27 females) children aged 4–7 years with Specific Language Impairment (SLI) who were delayed in their self-regulatory speech development. The self-regulatory speech and Tower of London (TOL) performance of children with SLI who received the intervention initially or after a waiting period was compared with that of 80 (48 male, 32 female) typically developing children who did not receive any intervention. Children were tested at three time points: Time 1- prior to intervention; Time 2 - after the first SLI group had received training and the second SLI group provided a wait-list control; and Time 3 - when the second SLI group had received training. At Time 1 children with SLI produced less self-regulatory speech and were impaired on the TOL relative to the typically developing children. At Time 2, the TOL performance of children with SLI in the first training group improved significantly, whereas there was no improvement for the second training group (the wait-list group). At Time 3, the second training group improved their TOL performance and the first group maintained their performance. No significant differences in TOL performance were evident between typically developing children and those with SLI at Time 3. Moreover, decreases in social speech and increases in inaudible muttering following self-regulatory speech training were associated with improvements in TOL performance. Together, the results show that self-regulatory speech training was effective in increasing self-regulatory speech and in improving planning and problem solving performance in children with SLI.
