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Boughner, R. L., & Papini, M. R. (2006). Appetitive latent inhibition in rats: preexposure performance does not predict conditioned performance. Behav. Process., 72(1), 42–51.
Abstract: Nonreinforced preexposure to a conditioned stimulus impairs subsequent conditioning with that stimulus. The goal of these studies was to assess the extent to which acquisition performance could be predicted from preexposure performance using a correlational approach. For both preexposure and autoshaping, four measures of performance were computed, including overall average lever pressing, lever pressing in the initial session, percentage change in lever pressing, and slopes. These measures were correlated in a large sample of rats trained in an autoshaping situation. None of the three measures of autoshaping performance was consistently predicted by any of the three measures of preexposure performance. These results are consistent with the view that latent inhibition is not reducible to long-term habituation.
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Henning, J. M., & Zentall, T. R. (1981). Imitation, social facilitation, and the effects of ACTH 4-10 on rats' bar-pressing behavior. Am J Psychol, 94(1), 125–134.
Abstract: The effects of ACTH 4-10 on rats' imitation learning was examined during the acquisition and extinction of a bar-press response for water reinforcement. Rats were exposed to either a bar-pressing conspecific (OB), an experimentally naive conspecific (ON), or an empty box (OE) during bar-press acquisition. In a factorial design, each rat was then exposed to one of the same three conditions during extinction. An 80 mcg dose of ACTH 4-10 was administered to half of the rats in each group prior to observation. Performance differences during acquisition were generally small, but significant performance differences during extinction were found. Social facilitation was indicated by the finding that rats extinguished in the presence of a conspecific exhibited significantly greater resistance to extinction than rats extinguished in the presence of an empty box. An imitation effect was also found. Rats that observed a bar-pressing conspecific during both acquisition and extinction (group OB-OB) showed significantly greater resistance top extinction than did groups OB-ON, CB-OE, or OE-OE. There were no significant effects of the hormone, however, relative to saline controls.
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Dusek, J. A., & Eichenbaum, H. (1997). The hippocampus and memory for orderly stimulus relations. Proc. Natl. Acad. Sci. U.S.A., 94(13), 7109–7114.
Abstract: Human declarative memory involves a systematic organization of information that supports generalizations and inferences from acquired knowledge. This kind of memory depends on the hippocampal region in humans, but the extent to which animals also have declarative memory, and whether inferential expression of memory depends on the hippocampus in animals, remains a major challenge in cognitive neuroscience. To examine these issues, we used a test of transitive inference pioneered by Piaget to assess capacities for systematic organization of knowledge and logical inference in children. In our adaptation of the test, rats were trained on a set of four overlapping odor discrimination problems that could be encoded either separately or as a single representation of orderly relations among the odor stimuli. Normal rats learned the problems and demonstrated the relational memory organization through appropriate transitive inferences about items not presented together during training. By contrast, after disconnection of the hippocampus from either its cortical or subcortical pathway, rats succeeded in acquiring the separate discrimination problems but did not demonstrate transitive inference, indicating that they had failed to develop or could not inferentially express the orderly organization of the stimulus elements. These findings strongly support the view that the hippocampus mediates a general declarative memory capacity in animals, as it does in humans.
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Thor, D. H., & Holloway, W. R. (1982). Social memory of the male laboratory rat. J. Comp. Physiol. Psychol., 96(6), 1000–1006.
Abstract: Used duration of social-investigatory behavior by 36 mature male Long-Evans rats as a measure of individual recognition in 5 experiments to assess social memory. In Exp I, the duration of social investigation during a 2nd exposure to the same juvenile (n[en space]=[en space]12) was directly related to the length of the interexposure interval. In Exp II, Ss were exposed to the same or different juvenile 10 min after an initial 5-min exposure to a novel juvenile; reexposure to the same juvenile elicited significantly less social investigation than an exposure to a different juvenile. Exps III and IV demonstrated that following a 5-min introductory exposure, social memory of the juvenile was relatively brief in comparison with that of mature Ss. Exp V revealed a retroactive interference effect on recently acquired memory for an individual: 12 mature Ss exposed to interpolated social experience engaged in significantly longer investigation of a juvenile than those with no interpolated social experience. The combined results suggest that (1) the rat normally engages in spontaneous learning of individual identity and (2) social memory may be a significant aspect of complex social interactions. (16 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved)
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Gibson, B. M., & Shettleworth, S. J. (2005). Place versus response learning revisited: tests of blocking on the radial maze. Behav Neurosci, 119(2), 567–586.
Abstract: Neurobiological and behavioral research indicates that place learning and response learning occur simultaneously, in parallel. Such findings seem to conflict with theories of associative learning in which different cues compete for learning. The authors conducted place+response training on a radial maze and then tested place learning and response learning separately by reconfiguring the maze in various ways. Consistent with the effects of manipulating place and response systems in the brain (M. G. Packard & J. L. McGaugh, 1996), well-trained rats showed strong place learning and strong response learning. Three experiments using associative blocking paradigms indicated that prior response learning interferes with place learning. Blocking and related tests can be used to better understand how memory systems interact during learning.
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Gibson, B. M., Shettleworth, S. J., & McDonald, R. J. (2001). Finding a goal on dry land and in the water: differential effects of disorientation on spatial learning. Behav. Brain. Res., 123(1), 103–111.
Abstract: Two previous studies, Martin et al. (J. Exp. Psychol. Anim. Behav. Process. 23 (1997) 183) and Dudchenko et al. (J. Exp. Psychol. Anim. Behav. Process. 23 (1997) 194), report that, compared to non-disoriented controls, rats disoriented before testing were disrupted in their ability to learn the location of a goal on a dry radial-arm maze task, but that both groups learned at the same rate in the Morris water maze. However, the radial-arm maze task was much more difficult than the water maze. In the current set of experiments, we examined the performance of control and disoriented rats on more comparable dry land and water maze tasks. Compared to non-disoriented rats, rats that were disoriented before testing were significantly impaired in locating a goal in a circular dry arena, but not a water tank. The results constrain theoretical explanations for the differential effects of disorientation on different spatial tasks.
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Alexander, F., & Davies, M. E. (1969). Studies on vitamin B12 in the horse. Br. Vet. J., 125(4), 169–176. |
Zentall, T. R., & Riley, D. A. (2000). Selective attention in animal discrimination learning. J Gen Psychol, 127(1), 45–66.
Abstract: The traditional approach to the study of selective attention in animal discrimination learning has been to ask if animals are capable of the central selective processing of stimuli, such that certain aspects of the discriminative stimuli are partially or wholly ignored while their relationships to each other, or other relevant stimuli, are processed. A notable characteristic of this research has been that procedures involve the acquisition of discriminations, and the issue of concern is whether learning is selectively determined by the stimulus dimension defined by the discriminative stimuli. Although there is support for this kind of selective attention, in many cases, simpler nonattentional accounts are sufficient to explain the results. An alternative approach involves procedures more similar to those used in human information-processing research. When selective attention is studied in humans, it generally involves the steady state performance of tasks for which there is limited time allowed for stimulus input and a relatively large amount of relevant information to be processed; thus, attention must be selective or divided. When this approach is applied to animals and alternative accounts have been ruled out, stronger evidence for selective or divided attention in animals has been found. Similar processes are thought to be involved when animals search more natural environments for targets. Finally, an attempt is made to distinguish these top-down attentional processes from more automatic preattentional processes that have been studied in humans and other animals.
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Beckers, T., Miller, R. R., De Houwer, J., & Urushihara, K. (2006). Reasoning rats: forward blocking in Pavlovian animal conditioning is sensitive to constraints of causal inference. J Exp Psychol Gen, 135(1), 92–102.
Abstract: Forward blocking is one of the best-documented phenomena in Pavlovian animal conditioning. According to contemporary associative learning theories, forward blocking arises directly from the hardwired basic learning rules that govern the acquisition or expression of associations. Contrary to this view, here the authors demonstrate that blocking in rats is flexible and sensitive to constraints of causal inference, such as violation of additivity and ceiling considerations. This suggests that complex cognitive processes akin to causal inferential reasoning are involved in a well-established Pavlovian animal conditioning phenomenon commonly attributed to the operation of basic associative processes.
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Yokoyama, S., & Radlwimmer, F. B. (1999). The molecular genetics of red and green color vision in mammals. Genetics, 153(2), 919–932.
Abstract: To elucidate the molecular mechanisms of red-green color vision in mammals, we have cloned and sequenced the red and green opsin cDNAs of cat (Felis catus), horse (Equus caballus), gray squirrel (Sciurus carolinensis), white-tailed deer (Odocoileus virginianus), and guinea pig (Cavia porcellus). These opsins were expressed in COS1 cells and reconstituted with 11-cis-retinal. The purified visual pigments of the cat, horse, squirrel, deer, and guinea pig have lambdamax values at 553, 545, 532, 531, and 516 nm, respectively, which are precise to within +/-1 nm. We also regenerated the “true” red pigment of goldfish (Carassius auratus), which has a lambdamax value at 559 +/- 4 nm. Multiple linear regression analyses show that S180A, H197Y, Y277F, T285A, and A308S shift the lambdamax values of the red and green pigments in mammals toward blue by 7, 28, 7, 15, and 16 nm, respectively, and the reverse amino acid changes toward red by the same extents. The additive effects of these amino acid changes fully explain the red-green color vision in a wide range of mammalian species, goldfish, American chameleon (Anolis carolinensis), and pigeon (Columba livia).
Keywords: Amino Acid Sequence; Animals; Base Sequence; COS Cells; Cats; Color Perception/*genetics; DNA Primers; Deer; Dolphins; *Evolution, Molecular; Goats; Guinea Pigs; Horses; Humans; Mammals/*genetics/physiology; Mice; Molecular Sequence Data; Opsin/biosynthesis/chemistry/*genetics; *Phylogeny; Rabbits; Rats; Recombinant Proteins/biosynthesis; Reverse Transcriptase Polymerase Chain Reaction; Sciuridae; Sequence Alignment; Sequence Homology, Amino Acid; Transfection
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