title: Operant-Pavlovian interactions: Ratio-schedules and the effects of the duration and location of a stimulus preceding response-independent food.
abstract: Two groups of four pigeons were exposed to either a fixed-ratio or a random-ratio schedule of reinforcement. Presentation of stimuli which preceded response-independent food delivery was then superimposed upon this operant baseline. The duration and the location of stimulus presentation were varied in different experimental conditions. Random-ratio schedules maintained higher response rates than fixed-ratio schedules. Response rates during presentation of the stimulus on the operant key exceeded response rates in the absence of stimulus presentation for the fixed-ratio subjects, but not for the random-ratio subjects. Similar observations were made when stimulus presentation occurred on a seperate stimulus key. During stimulus presentation on the stimulus key, response rates on the operant key were considerably higher for the random-ratio subjects than for the fixed-ratio subjects, especially during longer presentation of the stimulus (30 sec).
authors.affiliation: Tilburg University, Tilburg The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Van Hest
authors.forename: F
authors.initials: F
authors.lastname: Van Haaren
authors.forename: P
authors.initials: P
authors.lastname: Kop
authors.forename: F
authors.initials: F
authors.lastname: Van Der Schoot