|
|
Shettleworth, S. J., & Juergensen, M. R. (1980). Reinforcement and the organization of behavior in golden hamsters: brain stimulation reinforcement for seven action patterns. J Exp Psychol Anim Behav Process, 6(4), 352–375.
Abstract: Golden hamsters were reinforced with intracranial electrical stimulation of the lateral hypothalamus (ICS) for spending time engaging in one of seven topographically defined action patterns (APs). The stimulation used as reinforcer elicited hoarding and/or feeding and supported high rates of bar pressing. In Experiment 1, hamsters were reinforced successively for digging, open rearing, and face washing. Digging increased most in time spent, and face washing increased least. Experiments 2-5 examined these effects further and also showed that “scrabbling,” like digging, was performed a large proportion of the time, almost without interruption, for contingent ICS but that scratching the body with a hindleg and scent-marking showed relatively little effect of contingent ICS, the latter even in an environment that facilitated marking. In Experiment 6, naive hamsters received ICS not contingent on behavior every 30 sec (fixed-time 30-sec schedule). Terminal behaviors that developed on this schedule were APs that were easy to reinforce in the other experiments, but a facultative behavior, face washing, was one not so readily reinforced. Experiment 7 confirmed a novel prediction from Experiment 6--that wall rearing, a terminal AP, would be performed at a high level for contingent ICS. All together, the results point to both motivational factors and associative factors being involved in the considerable differences in performance among different reinforced activities.
|
|
|
|
Shettleworth, S. J., & Plowright, C. M. (1992). How pigeons estimate rates of prey encounter. J Exp Psychol Anim Behav Process, 18(3), 219–235.
Abstract: Pigeons were trained on operant schedules simulating successive encounters with prey items. When items were encountered on variable-interval schedules, birds were more likely to accept a poor item (long delay to food) the longer they had just searched, as if they were averaging prey density over a short memory window (Experiment 1). Responding as if the immediate future would be like the immediate past was reversed when a short search predicted a long search next time (Experiment 2). Experience with different degrees of environmental predictability appeared to change the length of the memory window (Experiment 3). The results may reflect linear waiting (Higa, Wynne, & Staddon, 1991), but they differ in some respects. The findings have implications for possible mechanisms of adjusting behavior to current reinforcement conditions.
|
|
|
|
Skov-Rackette, S. I., Miller, N. Y., & Shettleworth, S. J. (2006). What-where-when memory in pigeons. J Exp Psychol Anim Behav Process, 32(4), 345–358.
Abstract: The authors report a novel approach to testing episodic-like memory for single events. Pigeons were trained in separate sessions to match the identity of a sample on a touch screen, to match its location, and to report on the length of the retention interval. When these 3 tasks were mixed randomly within sessions, birds were more than 80% correct on each task. However, performance on 2 different tests in succession after each sample was not consistent with an integrated memory for sample location, time, and identity. Experiment 2 tested binding of location and identity memories in 2 different ways. The results were again consistent with independent feature memories. Implications for tests of episodic-like memory are discussed.
|
|
|
|
Slater, C., & Dymond, S. (2011). Using differential reinforcement to improve equine welfare: Shaping appropriate truck loading and feet handling. Behav. Process., 86(3), 329–339.
Abstract: Inappropriate behavior during common handling procedures with horses is often subject to aversive treatment. The present study replicated and extended previous findings using differential reinforcement to shape appropriate equine handling behavior. In Study 1, a multiple baseline across subjects design was used with four horses to determine first the effects of shaping target-touch responses and then successive approximations of full truck loading under continuous and intermittent schedules of reinforcement. Full loading responses were shaped and maintained in all four horses and occurrences of inappropriate behaviors reduced to zero. Generalization of the loading response was also observed to both a novel trainer and trailer. In Study 2, a changing criterion design was used to increase the duration of feet handling with one horse. The horse's responding reached the terminal duration criterion of 1 min and showed consistent generalization and one-week maintenance. Overall, the results of both studies support the use of applied equine training systems based on positive reinforcement for increasing appropriate behavior during common handling procedures.
|
|
|
|
Snycerski, S., Laraway, S., & Poling, A. (2005). Response acquisition with immediate and delayed conditioned reinforcement. Behav. Process., 68(1), 1–11.
Abstract: Groups comprising eight rats initially were exposed to response-independent water deliveries, then to conditions under which a lever-press response raised an empty dipper immediately or after a resetting delay of 15, 30, or 45 s. When their performance was compared to that of control animals using a 90% confidence level, six rats in the immediate-reinforcement group met the primary criterion for response acquisition during a single 6-h session; 4, 4, and 3 did so in the 15, 30, and 45 s delay groups, respectively. Similar evidence of acquisition was obtained when a 95% confidence level was used. With a 99% confidence level, however, evidence of acquisition was not compelling. Although these data appear to provide the first demonstration of response acquisition in the absence of handshaping or autoshaping under conditions where the putative reinforcer is both conditioned and delayed, they also demonstrate that whether response acquisition occurs depends, in part, on how it is defined.
|
|
|
|
Sole, L. M., Shettleworth, S. J., & Bennett, P. J. (2003). Uncertainty in pigeons. Psychon Bull Rev, 10(3), 738–745.
Abstract: Pigeons classified a display of illuminated pixels on a touchscreen as sparse or dense. Correct responses were reinforced with six food pellets; incorrect responses were unreinforced. On some trials an uncertain response option was available. Pecking it was always reinforced with an intermediate number of pellets. Like monkeys and people in related experiments, the birds chose the uncertain response most often when the stimulus presented was difficult to classify correctly, but in other respects their behavior was not functionally similar to human behavior based on conscious uncertainty or to the behavior of monkeys in comparable experiments. Our data were well described by a signal detection model that assumed that the birds were maximizing perceived reward in a consistent way across all the experimental conditions.
|
|
|
|
Urcuioli, P. J., DeMarse, T. B., & Zentall, T. R. (1998). Transfer across delayed discriminations: II. Differences in the substitutability of initial versus test stimuli. J Exp Psychol Anim Behav Process, 24(1), 47–59.
Abstract: In 2 experiments, pigeons were trained on, and then transferred to, delayed simple discriminations in which the initial stimuli signalled reinforcement versus extinction following a retention interval. Experiment 1 showed that discriminative responding on the retention test transferred to novel test stimuli that had appeared in another delayed simple discrimination but not to stimuli having the same reinforcement history off-baseline. By contrast, Experiment 2 showed that performances transferred to novel initial stimuli whether they had been trained on-baseline or off-baseline. These results suggest that the test stimuli in delayed simple discriminations acquire control over responding only in the memory task itself. On the other hand, control by the initial stimuli, if coded as outcome expectancies, does not require such task-specific training.
|
|
|
|
Waite, T. A. (2002). Interruptions improve choice performance in gray jays: prolonged information processing versus minimization of costly errors. Anim. Cogn., 5(4), 209–214.
Abstract: Under the assumption that selection favors minimization of costly errors, erroneous choice may be common when its fitness cost is low. According to an adaptive-choice model, this cost depends on the rate at which an animal encounters the choice: the higher this rate, the smaller the cost of choosing a less valuable option. Errors should thus be more common when interruptions to foraging are shorter. A previous experiment supported this prediction: gray jays, Perisoreus canadensis, were more error prone when subjected to shorter delays to access to food rewards. This pattern, though, is also predicted by an attentional-constraints model. Because the subjects were able to inspect the rewards during delays, their improved performance when subjected to longer delays could have been a byproduct of the experimentally prolonged opportunity for information processing. To evaluate this possibility, a follow-up experiment manipulated both delay to access and whether rewards could be inspected during delays. Depriving jays of the opportunity to inspect rewards (using opaque lids) induced only a small, nonsignificant increase in error rate. This effect was independent of length of delay and so the jays' improved performance when subjected to longer delays was not simply a byproduct of prolonged information processing. More definitively, even when the jays were prevented from inspecting rewards during delays, their performance improved when subjected to longer delays. The findings are thus consistent with the adaptive-choice model.
|
|
|
|
Watanabe, S. (2007). How animal psychology contributes to animal welfare. Appl. Anim. Behav. Sci., 106(4), 193–202.
Abstract: This article explores the contribution of animal psychology to animal welfare. Since animal welfare includes subjective welfare, it is crucial to know the subjective world of animals. Analysis of the concept of anthropomorphism is particularly important because it is a basic idea of animal ethics. The history of animal psychology, focusing on anthropomorphism and behaviourism, is briefly described, and then measurement of the subjective experience of animals in two ways, namely animal cognition and pleasure or reinforcing effects, is reported. Finally, it is suggested that animal welfare is not a permanently fixed idea, but a socially constructed one that can be changed. To gain widespread agreement about a socially constructed idea, it is important to know in which circumstances ordinary people employ metaphorical extension to an understanding of animal behaviour. In other words, a survey of “folk animal psychology” is important in order to establish a consensus about animal welfare.
|
|
|
|
West, R. E., & Young, R. J. (2002). Do domestic dogs show any evidence of being able to count? Anim. Cogn., 5(3), 183–186.
Abstract: Numerical competence has been demonstrated in a wide range of animal species. The level of numerical abilities shown ranges from simple relative numerousness judgements to true counting. In this study we used the preferential looking technique to test whether 11 pet dogs could count. The dogs were presented with three simple calculations: “1+1=2”; “1+1=1”; and “1+1=3”. These calculations were performed by presenting the dogs with treats that were placed behind a screen that allowed manipulation of the outcome of the calculation. When the dogs expected the outcome they spent the same amount of time looking at the result of the calculation as they did on the initial presentation. However, when the result was unexpected dogs spent significantly longer looking at the outcome of the calculation. The results suggest that the dogs were anticipating the outcome of the calculations they observed, thus suggesting that dogs may have a rudimentary ability to count.
|
|
