title: Ratio responding as a function of concurrent avoidance schedules, yoked shocks, and ratio value.
abstract: Fixed-ratio food-reinforced responding in rats was studied alone and with concurrent shock avoidance or with concurrent response-independent shocks matched to those that occurred in the avoidance condition. Under each condition, fixed-ratio size was increased over successive daily sessions. Fixed-ratio response rate generally passed through a maximum as a function of fixed-ratio size. Decreased fixed-ratio responding at values beyond the maximum occurred when (1) the time to complete a fixed ratio approximated the response-shock interval of the avoidance schedule, (2) the shock rate increased, and/or (3) the ratio requirements were so high that ratio strain occurred. Avoidance rates decreased slightly as fixed-ratio size increased.
authors.forename: K A
authors.initials: KA
authors.lastname: Wood
authors.forename: A J
authors.initials: AJ
authors.lastname: Happ
authors.forename: C K
authors.initials: CK
authors.lastname: Adams