| for survival | 3 | purpose |
| like all animals | 3 | other |
| without an intact dopamine system | 2 | other |
| rat → need → food | 11 |
| rat → require → food | 5 |
| rat → want → food | 3 |
| negative | neutral | positive |
| 0.338 | 0.587 | 0.075 |
| Raw frequency | 19 |
| Normalized frequency | 0.329 |
| Modifier score | 0.500 |
| Perplexity | 167.292 |