Table 2.
Cognitive performance measures.
| Test | Test time duration (min) | Test description | Cognitive function assessed |
|---|---|---|---|
| Motor control | 2 | A series of crosses is shown in different locations on the screen. After a demonstration of the correct way to point, using the forefinger of the dominant hand, the participant must touch the crosses in turn. | Familiarization with CANTAB touch screen interface |
| Spatial Working Memory | 7 | Subject searches through a series of boxes until they find a blue chip. When they find a blue chip they move it to the “home” area on the right hand side of the screen. They then have to look for the next blue chip which will not be in the same box as before. For each problem, the participant must not return to a box they have previously found a blue chip in. The number of boxes is gradually increased from three to eight boxes. The positions of the boxes used are changed from trial to trial to discourage the use of stereotyped search strategies. | Working memory and executive function |
| Paired Associate Learning | 8 | Boxes are displayed on the screen and open up in a randomized order to reveal a number of patterns. The participant must remember which pattern is in which box. The number of patterns gradually increases up to a number of eight but the participant has multiple attempts to remember each location. | Episodic memory |
| Stockings of Cambridge | 11 | The subject is shown two displays containing three colored balls. The displays are presented so they are easily perceived as stacks of colored balls held in stockings or socks suspended from a beam. The subject must use the balls in the lower display to copy the pattern shown in the upper display. The balls may be moved one at a time by touching the required ball, then touching the position to which it should be moved. The time taken to complete the pattern and the number of moves required are taken as measures of the subject's planning ability. | Executive functioning |
| Rapid Visual Information processing | 7 | The screen displays a box which randomly flashes numbers between 2 and 9. The participant must press the button on the screen to respond when they see a target sequence of 3-5-7. | Sustained attention |
CANTAB, Computerized Neuropsychological Test Automated Battery.