Cognitive tests
SECONDARY
All cognitive tests were completed on the Computerised Mental Performance Assessment System (COMPASS) (Northumbria University) computer software. This included simple reaction time (SRT), choice reaction time (CRT), secondary memory and mood. For SRT and CRT, 50 stimuli were presented on the screen at random intervals of 1–3 ms. Participants were seated 1 m away from the screen, with their hands placed on the response keys. They were asked to respond as quickly as possible by selecting the appropriate response key (spacebar for SRT, ‘M’ and ‘Z’ keys for CRT), and reaction time was recorded in milliseconds (ms). For SRT, participants had to hit the spacebar as soon as they saw the stimuli, whereas the CRT required a different response depending on the stimulus presented. For example, the screen would show an arrow pointing either left or right. Participants would have to press the ‘Z’ key if the arrow was pointing left, or the ‘M’ key of the arrow was pointing right. The accuracy of responses was recorded as percentage (%). Secondary memory was tested using an immediate word recall test. Fifteen words were presented, each for 1 s, after which participants recalled as many words as possible within 60 s. The number of words and accuracy of recall were recorded. Mood was assessed using the Bond–Lader mood scales