Fig. 1

FR1 acquisition. There was no significant difference between strains in the days taken to reach criterion on this task (a). The SHR did not differ from the two comparison strains in terms of correct responses (b), incorrect responses (c), discrimination index (d), anticipatory responses (e) or late responses (f). However, they did show a decrease in total task activity relatively to both other strains (g) and increased reaction time (h) but not pellet collection time (i). Representative key shown in b