Effects of bilateral stimulation of the subthalamic nucleus and levodopa treatment on apathy and reward sensitivity
| Stimulation | Levodopa | Group (p value) | Treatment (p value) | Inter (p value) | |||
|---|---|---|---|---|---|---|---|
| Values expressed as mean ± SEM. The ANOVA results are shown as probability levels for the group effect (patients with stimulation versus patients with levodopa), the treatment effect (on treatment/off treatment), and the interaction between these two factors (Inter). | |||||||
| 1. Apathy Scale (total score) | |||||||
| “on” treatment | 11.2 ± 0.9 | 11.0 ± 1.5 | 0.91 | <0.0001 | 0.55 | ||
| “off” treatment | 13.4 ± 1.2 | 14.0 ± 1.5 | |||||
| 2. Stimulus Reward Association | |||||||
| Learning (number of trials) | |||||||
| “on” treatment | 19.2 ± 3.9 | 22.6 ± 5.6 | 0.37 | 0.30 | 0.81 | ||
| “off” treatment | 23.1 ± 4.6 | 28.8 ± 4.8 | |||||
| Reversal (number in 30 trials) | |||||||
| “on” treatment | 1.6 ± 0.2 | 1.3 ± 0.2 | 0.48 | 0.28 | 0.43 | ||
| “off” treatment | 1.3 ± 0.2 | 1.3 ± 0.2 | |||||
| Extinction (last error) | |||||||
| “on” treatment | 8.1 ± 1.1 | 14.2 ± 2.5 | 0.13 | 0.99 | 0.13 | ||
| “off” treatment | 10.5 ± 1.6 | 11.8 ± 1.9 | |||||
| 3. Gambling Task (advantageous minus disadvantageous choices) | |||||||
| “on” treatment | 25.4 ± 10.2 | 13.4 ± 6.9 | 0.39 | 0.65 | 0.56 | ||
| “off” treatment | 19.4 ± 9.6 | 14.2 ± 6.4 | |||||