The original MEG dataset was acquired from all 306 sensors (204 gradiometers and 102 magnetometers) during two different sessions for each participant and recorded as .fif files. As each session consists of two data files due to the session break, for better handling of the data, we have merged these files to create one single '.fif' file for each session. Thus, there are two raw '.fif' data files for each participant (i.e. one for each session). It is worth to be noted the data is available in two data formats i.e. MEG-BIDS format '.fif' and MATLAB compatible '.mat' file at the repository. In .mat format, each participant data is stored in two folders (i.e. session 1 and session 2) under the root directory of 'MEG_mat'.