Table 1.
Clinical and demographic characteristics of the PD sample.
Figure 1.
Summary of results on the Cambridge Gamble Task (CGT).
Stimulation did not affect the performance in any of the variables of interest. The purple bars and dashed line summarize the results in the off stimulation condition; the green bars and solid line those in the on stimulation condition.
Figure 2.
Results on the psychological questionnaires.
Upper panel: Patients reported lower scores of impulsivity when on stimulation. AI, attentional impulsivity; MI, motor impulsivity; NPI, non-planning impulsivity. Middle panel: patients obtained higher scores of sensitivity to punishment than to reward independently of the condition of stimulation. SP, sensitivity to punishment; SR, sensitivity to reward. Lower panel: No differences emerged on the QDQ; DA, delay aversion; DD, delay discounting. Please note that unlike the previous two questionnaires, higher scores on the QDQ reflect a lower tendency to impulsivity.
Figure 3.
Correlation of delay aversion scores on the Cambridge Gamble Task (CGT) and delay aversion scores on the Quick Delay Questionnaire (QDQ) in the on stimulation condition.
A significant negative correlation was found (r = −0.626 p = 0.029) suggesting that higher scores of delay aversion on the CGT were correlated to more negative feelings when waiting for rewards.