Anderson, M. C., & Shettleworth, S. J. (1977). Behavioral adaptation to fixed-interval and fixed-time food delivery in golden hamsters. J Exp Anal Behav, 27(1), 33–49.
Abstract: Food-deprived golden hamsters in a large enclosure received food every 30 sec contingent on lever pressing, or free while their behavior was continuously recorded in terms of an exhaustive classification of motor patterns. As with other species in other situations, behavior became organized into two main classes. One (terminal behaviors) increased in probability throughout interfood intervals; the other (interim behaviors) peaked earlier in interfood intervals. Which class an activity belonged to was independent of whether food was contingent on lever pressing. When food was omitted on some of the intervals (thwarting), the terminal activities began sooner in the next interval, and different interim activities changed in different ways. The interim activities did not appear to be schedule-induced in the usual sense. Rather, the hamsters left the area of the feeder when food was not due and engaged in activities they would normally perform in the experimental environment.
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Gibson, B. M., Juricevic, I., Shettleworth, S. J., Pratt, J., & Klein, R. M. (2005). Looking for inhibition of return in pigeons. Learn Behav, 33(3), 296–308.
Abstract: We conducted four experiments in order to investigate whether pigeons' responses to a recently attended (i.e., recently pecked) location are inhibited. In Experiments 1 and 2, stimulus displays were similar to those used in studies of inhibition of return (IOR) with humans; responses to cued targets tended to be facilitated rather than inhibited. In Experiments 3 and 4, birds were presented with stimulus displays that mimicked clusters of small grains and were relatively localized, which should have been more appropriate for detecting IOR in pigeons. The results from these experiments again provided evidence for facilitation of responding to cued targets, rather than for IOR.
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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. (2003). Competition among spatial cues in a naturalistic food-carrying task. Learn Behav, 31(2), 143–159.
Abstract: Rats collected nuts from a container in a large arena in four experiments testing how learning about a beacon or cue at a goal interacts with learning about other spatial cues (place learning). Place learning was quick, with little evidence of competition from the beacon (Experiments 1 and 2). Rats trained to approach a beacon regardless of its location were subsequently impaired when the well-learned beacon was removed and other spatial cues identified the location of the goal (Experiment 3). The competition between beacon and place cues reflected learned irrelevance for place cues (Experiment 4). The findings differ from those of some studies of associative interactions between cue and place learning in other paradigms.
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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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Hampton, R. R., Healy, S. D., Shettleworth, S. J., & Kamil, A. C. (2002). Neuroecologists' are not made of straw. Trends. Cognit. Sci., 6(1), 6–7.
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Hampton, R. R., Sherry, D. F., Shettleworth, S. J., Khurgel, M., & Ivy, G. (1995). Hippocampal volume and food-storing behavior are related in parids. Brain Behav Evol, 45(1), 54–61.
Abstract: The size of the hippocampus has been previously shown to reflect species differences and sex differences in reliance on spatial memory to locate ecologically important resources, such as food and mates. Black-capped chickadees (Parus atricapillus) cached more food than did either Mexican chickadees (P. sclateri) or bridled titmice (P. wollweberi) in two tests of food storing, one conducted in an aviary and another in smaller home cages. Black-capped chickadees were also found to have a larger hippocampus, relative to the size of the telencephalon, than the other two species. Differences in the frequency of food storing behavior among the three species have probably produced differences in the use of hippocampus-dependent memory and spatial information processing to recover stored food, resulting in graded selection for size of the hippocampus.
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Hampton, R. R., & Shettleworth, S. J. (1996). Hippocampus and memory in a food-storing and in a nonstoring bird species. Behav Neurosci, 110(5), 946–964.
Abstract: Food-storing birds maintain in memory a large and constantly changing catalog of the locations of stored food. The hippocampus of food-storing black-capped chickadees (Parus atricapillus) is proportionally larger than that of nonstoring dark-eyed juncos (Junco hyemalis). Chickadees perform better than do juncos in an operant test of spatial non-matching-to-sample (SNMTS), and chickadees are more resistant to interference in this paradigm. Hippocampal lesions attenuate performance in SNMTS and increase interference. In tests of continuous spatial alternation (CSA), juncos perform better than chickadees. CSA performance also declines following hippocampal lesions. By itself, sensitivity of a given task to hippocampal damage does not predict the direction of memory differences between storing and nonstoring species.
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Hampton, R. R., & Shettleworth, S. J. (1996). Hippocampal lesions impair memory for location but not color in passerine birds. Behav Neurosci, 110(4), 831–835.
Abstract: The effects of hippocampal complex lesions on memory for location and color were assessed in black-capped chickadees (Parus atricapillus) and dark-eyed juncos (Junco hyemalis) in operant tests of matching to sample. Before surgery, most birds were more accurate on tests of memory for location than on tests of memory for color. Damage to the hippocampal complex caused a decline in memory for location, whereas memory for color was not affected in the same birds. This dissociation indicates that the avian hippocampus plays an important role in spatial cognition and suggests that this brain structure may play no role in working memory generally.
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Jones, J. E., Antoniadis, E., Shettleworth, S. J., & Kamil, A. C. (2002). A comparative study of geometric rule learning by nutcrackers (Nucifraga columbiana), pigeons (Columba livia), and jackdaws (Corvus monedula). J Comp Psychol, 116(4), 350–356.
Abstract: Three avian species, a seed-caching corvid (Clark's nutcrackers; Nucifraga columbiana), a non-seed-caching corvid (jackdaws; Corvus monedula), and a non-seed-caching columbid (pigeons; Columba livia), were tested for ability to learn to find a goal halfway between 2 landmarks when distance between the landmarks varied during training. All 3 species learned, but jackdaws took much longer than either pigeons or nutcrackers. The nutcrackers searched more accurately than either pigeons or jackdaws. Both nutcrackers and pigeons showed good transfer to novel landmark arrays in which interlandmark distances were novel, but inconclusive results were obtained from jackdaws. Species differences in this spatial task appear quantitative rather than qualitative and are associated with differences in natural history rather than phylogeny.
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