The effects of activity conditioned in random CS/US training on performance in autoshaping

Abstract

Random presentations of key lights and food retarded acquisition and suppressed asymptotic rates of keypecking in autoshaping. Sequences of 10 sessions of random training alternated with 10 sessions of autoshaping resulted in poor performance (in terms of both the acquisition and asymptotic indices) relative to a group that received sequences of CS-only (rather than random) training alternating with autoshaping. When the birds that previously were trained with the random sequence were exposed to CS-alone extinction, retardation of acquisition was alleviated but the asymptotic suppression was not (Experiment 1). Pigeons with a history of autoshaping without prior random training showed no asymptotic suppression when exposed to the random procedure. These birds, when switched between two-session sequences of random training alternating with two-session sequences of autoshaping, were able to (1) surpass pigeons that received CS-only rather than random treatment in terms of asymptotic levels of responding in autoshaping, and (2) showed improvement in extinction performance with repeated randomlautoshaping sequences (Experiment 2). Detailed observations of pigeons in random training showed that stereotypic activity behaviors were acquired, and these generally persisted in autoshaping; the degree of change in these behaviors was related to asymptotic rates of keypecking in autoshaping (Experiment 3). The same kinds of behaviors were observed when pigeons initially were autoshaped, and these persisted in subsequent random and fixed-intervaI10-sec training. We suggest that the suppression effect is reflected in activity, conditioned in random training, which persists in autoshaping (especially if the activity is compatible with the kinds of behaviors elicited by the autoshaping contingency itself), and that the effect may be a deficit due to performance factors rather than to associative learning.If pigeons are exposed to random presentations of keylights (conditioned stimuli, CSs) and food (unconditioned stimuli, USs), subsequent keypeck acquisition is impaired relative to that of pigeons without such "random CS/US" exposure (Tomie, 1976a(Tomie, , 1976b(Tomie, , 1981. This "retardation" effect is very reliable and has provided support for several models of classical conditioning that focus on the acquisition either of associations (Mackintosh, 1975; Rescoda & Wagner, 1972) or of performance tendencies (Gibbon & Balsam, 1981) that interfere with the new conditioned response (CR). Typically, however, random CS/US training has another effect beyond that of slowing down the rate of acquisition of the CR. It also prevents responding from reaching asymptotic levels seen in animals without random pretraining (Balsam & Schwartz, 1981;Durlach, 1984; Gamzu & Williams, 1971, 1973 Randich & Lol.ordo, 1979; Tomie, 1976a Tomie, , 1976bTomie, , 1981 Tomie, Murphy, Fath, & Jackson, 1980). Some of the data from Experiment 1 were presented at the meeting of the American Psychological Association in Anaheim, August 1983, and some of...

Sign‐ Versus Goal‐tracking: Effects of Conditioned‐stimulus‐to‐unconditioned‐stimulus Distance

“…Besides providing information about behavior during the CS, the present study also provides information about behavior during the ITI and about the differential control exerted by the CS and the ITS. Behavior during the ITI was stereotyped, as has been found in other studies (e.g., Brandon & Paul, 1987;Eldridge & Pear, 1987;Matthews & Lerer, 1987;Pear & Eldridge, 1984), and the pattern of the stereotyped behavior did not depend in any obvious way on the position of the CS and the ITS or on whether sign-tracking or goal-tracking occurred. It should be noted that although in this study the movement patterns during the ITI tended to occur along the wall on which the food aperture was located, this is not always the case (Eldridge & Pear, 1987).…”

Testing response generation rules.

“…Thus, autoshaped keypecking by pigeons might not be a good preparation for testing the predictions of the comparator hypothesis concerning modification of the associative status of the comparator stimuli after completion of CS training. Consistent with this conclusion, Locurto, Travers, Terrace, and Gibbon (1980) found that unsignaled US presentations to pigeons in a context subsequently used for autoshaping resulted in elevated activity levels (also see Brandon & Paul, 1987). The elevated activity levels apparently distracted the animals from the keylight CSs, thereby impeding acquisition of the keylight—US association.…”

Role of signals for unconditioned stimulus absence in the sensitivity of autoshaping to contingency.

“…The results of testing suggest that if this was the case, those responses interfered not only with performance to the target, but also with learning about the target; removing the signal from the target during testing failed to have a dramatic effect on responding to the target. Competing responses elicited by the signal may have interfered with learning about the target by removing the pigeons from the key and thus reducing the pigeons' exposure to the target-food relation (cf., Brandon & Paul, 1987). On the other hand, the blocking effect might be due not to peripheral response competition but rather to associative interference at a more central level of processing (e.g., Mackintosh, 1975; Rescorla & Wagner, 1972; Wagner, 1981).…”