Table 1.

Cambridge Neuropsychological Task Automated Battery (CANTAB) tasks used in SPD489-404

CANTAB task	Domain of cognition	Description	Key variables	Additional variables
Delayed matching to sample (DMS)	Recognition memory and short-term visual memory	The participant is shown a complex visual pattern and must then select the matching pattern from four similar patterns shown simultaneously, or with a delay of 0, 4 or 12 s after the sample is concealed and the choices are revealed	Per cent correcta	Per cent correct (simultaneous) Per cent correct (0-s delay) Per cent correct (4-s delay) Per cent correct (12-s delay) Per cent correct (all trials excluding simultaneous)
			Median reaction time on correct trialsb	Median reaction time on correct trials (simultaneous) Median reaction time on correct trials (0-s delay) Median reaction time on correct trials (4-s delay) Median reaction time on correct trials (12-s delay)
Spatial working memory (SWM)	Retention and manipulation of visuospatial information, as well as some aspects of executive function	The participant is shown a number of square ‘boxes’ and must find a blue token in each box. The number of boxes increases from four to six and then to eight; the colour and position of the boxes change from trial to trial	Total between-search errorsc	Between-search errors (four tokens) Between-search errors (six tokens) Between-search errors (eight tokens)
Stop signal task (SST)	Response inhibition and mental processing speed	The participant must respond to an arrow pointing in one of two directions by pressing the corresponding button, but must inhibit their response if a sound is heard	Stop signal reaction timed	Reaction time SD on ‘go’ trials
Reaction time (RTI)	Motor and mental response speed and some aspects of impulsivity	The participant must respond in one of a variety of ways to the appearance of a yellow dot, either in a single location or in one of five possible locations. The participant is encouraged to go faster on each series of trials	Simple median reaction timee	Simple reaction time SD Simple premature response errors
			5-choice median reaction timef	5-choice reaction time SD 5-choice premature response errors

SD standard deviation

^aThe proportion of assessed trials (%) in which the participant responded correctly on their first attempt, for all trials (key variable) or for each of the four trial types (additional variables). Higher values indicate better cognitive function

^bThe median reaction time in assessed trials in which the participant responded correctly, for all trial types (key variable) or for each of the four trial types (additional variables). Lower values indicate better cognitive function

^cThe number of times the participant returned to a box in which a token had already been found, in all trials (key variable) or separately in trials with four, six or eight tokens (additional variables). Lower values indicate better cognitive function

^dThe time between ‘go’ and ‘stop’ stimuli at which the participant inhibited their response in 50% of trials (key variable) and its SD (additional variable). Lower values indicate better cognitive function

^eIn assessed trials with a single stimulus, the time between stimulus and correct response (key variable) and its SD (additional variable), and the number of trials in which the participant responded prematurely (additional variable). Lower values indicate better cognitive function

^fIn assessed trials with a stimulus in one of five possible locations, the time between stimulus and correct response (key variable) and its SD (additional variable), and the number of trials in which the participant responded prematurely (additional variable). Lower values indicate better cognitive function