Table 1.
Dopamine-related parameters in COVIS
| Cools et al. (2006) | Flowers & Robertson (1985) | Nadler et al. (2010) | ||||||
|---|---|---|---|---|---|---|---|---|
| Parameters | OC | PD | YC | OC | PD | Pos | Neu | |
| 0.22 | - | 0.19 | 0.23 | 0.32 | 0.60 | 1.50 | ||
| γ | 0.10 | 1.85 | 0.25 | 3.00 | 25.00 | 15.00 | - | |
| λ | 12.1 | 12.0 | 9.0 | 7.0 | 0.5 | 7.0 | 1.0 | |
| a | 1.1 | - | 1.0 | - | - | 1.0 | - | |
| Dslope | 0.80 | 0.15 | 0.80 | 0.25 | 0.15 | 0.80 | - | |
| Dmax | 0.60 | 0.35 | 1.00 | 0.60 | 0.35 | 1.00 | - | |
| Dbase | 0.15 | 0.10 | 0.20 | 0.15 | 0.10 | 0.20 | - | |
Note. YC = young control; OC = old control; PD = Parkinson’s disease patients; Pos = Positive affect; Neu = Neutral affect. Note that Dmax and Dbase are not free parameters. They are calculated as a function of the proportion of DA cell lost (see Section 5.3).