A Rapid Automatic Technique for Generating Operant Key‐press Behavior in Rats

Abstract

Experimentally naive rats were trained to key press on a fixed-ratio 10 schedule of food reinforcement by a completely automatic procedure within a single, 1-hr session. Control procedures demonstrated that the resulting behavior was an operant, under control of the schedule of reinforcement and the specified reinforcing stimulus (food). A simple, combination food-tray operandum, also described, was used as the basis for the training technique. Teichner (1952) and Bremner and Trowill (1962) described combined operandum-reinforcement devices for use with food pellets, which facilitated lever-press training of rats and which did not require response shaping by an experimenter. Procedures in which responding was automatically acquired have also been used with rhesus monkeys (Sidman and Fletcher, 1968) and bobwhite quail (Gardner, 1969), based on the procedure developed by Brown and Jenkins (1968) used in these experiments was based on the species-specific tendency of hungry rats to sniff the area in which food was obtained and to "'nose" objects. METHOD SubjectsIn the present experiments, the weights of experimentally naive male Charles River rats (Sprague-Dawley) were decreased to approximately 80% of original weight (150 to 190 g) by 48 hr of food deprivation followed, on the next day, by 6 g per day of the food pellets used as reinforcers in the experimental procedures. Three different rats were used in each of the five experiments reported and all rats were housed in individual home cages with free access to water. ApparatusThe rats were tested in three cubic chambers (230 mm, each dimension) with grid floors, housed in sound-attenuating, ventilated, wood boxes. Conventional scheduling and recording equipment was used. Noyes food pellets (0.045 g) were delivered into a recessed food tray (Gerbrands Recessed Tray for Model D-1 Feeder; Cat. No. G-7020), modified for use as an operandum.As illustrated in Fig. 1

Acquisition of a nose-poke response in rats as an operant

“…Without this contingency, the rate of nose poking did not increase, even when food was delivered as frequently as for the animals acquiring the response (compare Group 2 and its yoked partners) . This result agrees with previous findings showing that the cont ingency between an operant and food is c rucial for acquisition of an operant response (Davidson et al, 1971) . The degree to which classical conditioning processes may have influenced response acquisition appears to be minimal.…”

“…The current data suggest that acquisition of the nose-poke response occurs much more rapidly than that for other operant responses . Although previous reports have used the nose-poke response for food in the rat , those reports either did not present detailed acquisition data (Hayes, Latta!, & Myerson, 1979;Oakes , Rosenblum, & Fox, 1982) or delivered the food within the hole used for the response (Davidson, Davis, & Cook, 1971;Hayes et al, 1979), thus confounding the operant and the consumatory response . Nevertheless, these reports do confirm that the nose-poke operant is acquired rapidly .…”

AGGRESSION AS A REINFORCER: OPERANT BEHAVIOR IN THE MOUSE‐KILLING RAT1

“…Thus, operant rate in the presence of non-contingent mouse presentation was higher than the possible rate in a session during wlhich mouse presentation and the 1-min timeout followed each key press. This high rate was probably due in part to the activation resulting from the random presentation of mice, and in part to a kind of "autoslhaping" similar to that demonstrated for food-motivated responding in rats (Davidson, Davis, and Cook, 1971;Smith, Borgen, Davis, and Pace, 1971). In fact, three of the rats were responding reliably after two sessions of contingent mouse presentation, and only one rat required manual shaping.…”

Determinants of Reinforcer Accumulation During an Operant Task

“…A relation between responding and the spatial distance between response and consequence was suggested by Bremner and Trowell (1962) and Davidson, Davis, and Cook (1972). These investigators described an operandum for rats that minimized the distance between the operandum and reinforcer dispenser by incorporating the two into a single unit.…”