抄録
Phrasing effect of short intertrial interval (ITI) on the serial pattern learning was investigated in a runway experiment. In acquision, all 10 rats were given three repetitions of 14-7-3-1-0 subpattern daily over Days 1-80. For Group NP (non phrasing), all daily 15 trials were separated by a 15-min ITI. Group GP (good phrasing) and Group BP (bad phrasing) received the same procedure as Group NP except, instead of the 15-min ITI, a 15-s ITI was inserted between the 0 pellet and 14 pellets trial in the former, and a 15-s ITI was inserted between the 3 pellets and 1 pellet trial in the latter. Means of the last 4 days of acquisition as indicated by running speed showed that Group GP produced better anticipation of the 0 pellet trial than Group NP, and that Group BP produced the poorest anticipation. In Group BP, rats ran more slowly on the 1 pellet trial, that occurred after the 15-s ITI, than on the 0 pellet trial in each of the first and second subpatterns. These results suggest that a shorter ITI plays dual roles, as a phrasing cue and as a discriminative stimulus in the serial pattern learning as that does in reinforcement-nonreinforcement pattern learning.
