A study has shown that brain stimulation does not enhance any training gains from working memory training.
Working memory (WM) is the cognitive ability that enables us to remember information for short periods of time. It also allows us to juggle multiple thoughts and focus on what we are doing. Individuals with poor WM struggle in many everyday tasks, and often have poor reading and maths skills. For this reason, scientists and practitioners have become increasingly interested in using computerised memory training as a tool to enhance WM capacity.
People who train on WM tasks show robust improvements on the tasks on which they practice during training. However, there is very little evidence that the benefits of training extend beyond WM tasks that are similar to the training tasks or that they lead to improvements in everyday functions that rely on WM (e.g. learning, paying attention). For WM training to be considered an effective therapeutic tool for enhancing WM performance in everyday tasks, it is necessary to establish methods that promote the generalisation of training gains.
Non-invasive brain stimulation, which involves the delivery of a very weak electrical current to the scalp to stimulate an underlying brain region, has been used to enhance the benefits of maths training. The aim of this study was to investigate whether combining brain stimulation with WM training could increase training gains and promote the generalisation of training effects. Thirty participants completed 10 days of computerised working memory training with either a real or fake dose of brain stimulation. As expected, all participants showed improvements on both the training tasks and on untrained memory tasks that were very similar to the training tasks. Stimulation did not enhance training gains, nor did it lead to greater improvements on tests of other cognitive abilities (e.g. IQ, maths). These findings do not, therefore, support the use of brain stimulation combined with WM training as an intervention for the remediation of WM problems.