Successful task manipulations were defined as moving the door and retrieving a reward, whereas an unsuccessful task manipulation was defined as moving the door but not gaining a reward.
In other words, this control task was important to show that the task manipulation was successful, in that both endogenous and exogenous cues guided attention.
The primary effect of this task manipulation is seen for patients "on" medication, who show opposite trends in their behaviour: in the 4-choice paradigm, repetitions increased with increasing UPDRS, but in the 3-choice task repetitions decreased with increasing UPDRS.
Indicating that MB task manipulations were also associated with a general variation in error rates, subjects were more accurate on repetition trials (F 1, 42) = 14.4; p <.001), on long CTI trials (F 1, 42) = 7.0; p <.05) and on trials containing univalent stimuli (F 1, 42) = 41.1; p <.001).
Detailed data reporting is limited to findings confirming that task manipulations were successful and those of particular theoretical relevance for neurocognitive modelling of ADHD.
Age, sex and the number of successful task manipulations were used as fixed factors and individual identity nested in groups as random factors.
Confirming that the task manipulations were associated with the expected changes in RTs, significant main effects were obtained for the factors of trial type (F 1, 42) = 60.0; p <.001), CTI (F 1, 42) = 358.5; p <.001), and valence (F 1, 42) = 4.4; p <.05).
As this population are most susceptible to glucose facilitation during more cognitively demanding tasks, a dual task (high vs. low effort) manipulation was introduced during encoding.
Furthermore, the effect of location on reporting errors was present even when its manipulation was orthogonal to the task at hand.
Second, task manipulation may be affected by strategy confounds [Demonet et al., 1994; Noppeney and Price, 2003].
