Two excel files with the behavioural and alpha power data. One file contains all the behavioural data from phase 2 and 3 (accuracy and RT), and the other file contains the phase 1 alpha power values for semantic versus non-semantic processing; phase 2 DM alpha power; phase 1 versus phase 2 alpha correlations, and phase 2 alpha with phase 3 behaviour correlations. These files contain all the necessary data so that reviewers and other interested readers are able to obtain every statistical result reported in the paper.