In the largest non-pharmacological trial ever in children with fragile X syndrome (FXS), UC Davis researchers found that large-scale, in-home cognitive interventions are feasible and may be beneficial for individuals with the syndrome and potentially other intellectual disabilities.

The findings are significant given that human clinical trials of drug therapies aimed at normalizing specific neurobiological abnormalities in FXS have not been successful despite promising results with animal models in the laboratory.

“In this study we are filling a critical gap in our field by focusing on a non-pharmacological intervention, with the long-term concept that patients might show accelerated learning in combination with these targeted treatments,” said David Hessl, a professor in the UC Davis Department of Psychiatry and Behavioral Sciences and the MIND Institute.

For the study, published April 15 in the Journal of Neurodevelopmental Disorders, Hessl and colleagues examined whether Cogmed, a series of computer-based memory training games, is effective in improving working memory and executive function in children with FXS.

Researchers saw 100 families three times in a blinded, randomized, controlled trial in their own homes throughout North America. One group received Cogmed, the widely available "full dose" version of the training. The comparison control group received an identical non-adaptive version, meaning that unlike Cogmed, the training was not designed to be progressively challenging.

“The hypothesis was that the adaptive group would significantly outperform the non-adaptive control group,” Hessl said. “However, it turned out that both groups showed significant gains, and overall we did not see a differential improvement above the control condition.”

Hessl suspects that both groups benefitted from the overall intervention, but it cannot be known for certain whether Cogmed itself caused the gains until additional comparison studies are done.

“But we provided strong evidence that large-scale behavioral/cognitive interventions can be done with high fidelity in this population, and that Cogmed might be a good platform for looking at whether drugs can accelerate a learning or training process,” Hessl said.