THE FORM OF THE AUTO‐SHAPED RESPONSE WITH FOOD OR WATER REINFORCERS¹

Abstract

The relation between the form of auto-shaped responses to the lighting of a key and the consummatory responses of pecking grain and (Irinking wvater was examined in pigeons.Responses on the key were analyzed by means of high-speed photography, recordings of the force of contact, and judges' ratings of response-formii based on filni and videotape recordings. The first experiment showed that food-deprived birds presented grain as a reinforcer responded on the key with a grain-pecking movement, while water-deprived birds presented water as a reinforccr responded with drinking-like movemllents. The second and third experimnents showed that the resemllblance between auto-shaped and consummatory responses does not require the dominance of the deprivational state appropriate to the reinforcer. Changing the domiiinant state of deprivation did not illinmlediately change the form of the key response, and in subjects simultaneously deprived of food and water, the form1 of response depended on the reinforcer. In the fourth and fifth experiments, subjects simultaneously deprived of food and water received one stimuluis signalling food and another signalling water in a randomii series. In miiost subjects, the response to each stimulus resembled the consummatory responsc to the particular reinforcer that was signalled by the stimulus. This result demonstrates the role of association between a stimulus and a reinforcer in producing a rcsemiiblance of the auto-shaped response to the consuimmatory response.The procedure used in auto-slhaping (Brown and Jenkins, 1968) conforms to the paradigm for classical conditioning (Pavlov, 1927 respond to the conditioned stimulus (CS) and conditioned response (CR). As in classical conditioning, the auto-shaped response has no effect upon the occurrence of the reinforcer; the presentation of grain is contingent upon illumination of the key, but is not contingent upon the animal's behavior.Standard control procedures have shown that auto-shaped pecking is not an artifact of sensitization or pseudo-conditioning (Brown and Jenkins, 1968; Brown, 1968a Brown, , 1968b. The pigeon's approach to and contact with the key dlepends upon the contingent pairing (association) of the stimulus and reinforcer. The parallel with classical conditioning suggests that the specific form of the auto-shaped behavior might also depend upon a stimulusreinforcer association. Perhaps the pigeon pecks the key because pecking is the consummatory response elicited by grain.The stiggestion receives some support from experiments witlh otlher species and other reinforcers. Gardner (1969) reported that bobwhite quail, like pigeons, peck at stimuli that have been paired witlh grain. Squier (1969) reported that auto-shaped tilapia reacted to response keys with species-specific feeding movements, such as those used ordinarily in 163

Motivational mechanisms and schedule-induced behavioral stereotypy

“…Latencies to initiate pecking and pecking rates were comparable. Although this might suggest that pecking is a generic response to localized ues signals, as in "sign-tracking" (Hearst & Jenkins, 1974), the higher frequency of very fast pecks observed with water presentations suggests a different pecking topography, a fact that is documented in the literature (Jenkins & Moore, 1973).…”

“…This work suggests that, as with food UCSs, terminal behavior also develops with water UCSs but often its form is different (Boakes, Poli, Lockwood, & Goodall, 1978;Davey & Cleland, 1982;Timberlake, 1983b). With pigeons, Jenkins and Moore (1973) reported that the topography ofautoshaped keypecking differs in response to food and water presentations in a way that resembles the consummatory response: food-induced pecks are more forceful, open-beaked, and of shorter duration, whereas waterinduced pecks are slower, sustained, and closed-beak, and often occur together with swallowing movements. The topography of food-and water-induced terminal responding is also thought to depend on the nature of the signaling stimulus and its interaction with the motivational condition (Timberlake, 1983b).…”

“…In fact, the proportion of very short interresponse intervals (less than .2 sec) was higher for all animals in the water phase (Wilcoxon test, T+ = 21, P < .015). Jenkins and Moore (1973) reported that food-elicited pecks were more discrete and forceful, with the animal moving its head back before it "hammered" the key, whereas, in anticipation of water, subjects "nuzzled" the key. Thus, birds in the water condition may have been holding the response key close to the trigger point of the switch and jittering it to produce faster pecks than would be possible with the hammering topography.…”

What's in a peck? Using fixed action pattern morphology to identify the motivational basis of abnormal feather-pecking behaviour

“…For example, rats direct social behaviour at another rat whose presence indicates a future food reward, as rats include social aspects in their feeding behaviour (Timberlake 1975). Thus, pigeons conditioned to peck a key for a food or water reward will also direct 'eating' or 'drinking' pecks to the key, respectively, further showing that the motivation behind each movement affects the motor patterns expressed (Jenkins & Moore 1973). Based on these characteristics, we planned to use FAPs in an attempt to uncover the motivation behind abnormal feather pecking.…”

Fractionating Impulsivity: Contrasting Effects of Central 5-HT Depletion on Different Measures of Impulsive Behavior

“…In a subsequent testing stage known as the negative automaintenance schedule, or omission phase, subjects continue to approach the CS þ even though these responses are now punished by cancellation of the scheduled reward (Browne, 1976;Jenkins and Moore, 1973;Williams and Williams, 1969). Such behavior suggests that the animal is unable to withhold from making the motor response once it has become associated with food reward, thus reflecting impulsive action or 'motoric impulsivity'.…”