Figure 2.

Probability of accurate response on the first 20 discrimination and reversal trials. The probability of a correct response on discrimination and reversal trials provides an indication of the time course of improvement of performance accuracy following the start of a new stimulus set and following stimulus reversal. Inset shows the number of trials to reach criterion performance on the discrimination trials at the 0.2 and 0.5 g/kg doses. At the 1.0 g/kg dose, most subjects failed to reach criterion.