Abstract: An early training procedure commonly termed “foal imprint training” is widely promoted in the horse industry. However, there have been no published scientific investigations of its efficacy. This study determined the effects of a training procedure on foals and their reaction to stimuli used in the early training procedure, and to a novel stimulus, at 1, 2 and 3 months of age. Twenty-five foals received a standard training procedure at 2, 12, 24, and 48 h after birth. After the training procedure, the foals received minimal additional handling that included veterinary treatments and occasional relocation. Twenty-two foals born over the same time period served as controls. All 47 (25 trained, 22 control) foals were tested at 1 month of age. Only 20 were available for testing at 2 months of age, and nine were available at 3 months. Percentage change from baseline heart rate, time required to complete exposure to each stimulus (foals that were more reactive took longer) and the behavior of each foal during the introduction of each stimulus were recorded. Overall, the control foals tended to receive lower (better) behavioral scores at 1 and 2 months of age. Foals that underwent the training procedure tended to require less time to complete exposure to the stimulus and had lower heart rates during exposure to the stimuli at 1 and 2 months of age. By 3 months of age, there were no significant differences between trained and control foals for any measures. Early training was not efficacious in this study.

Abstract: In the wake of telling critiques of the foundations on which earlier conclusions were based, the last 15 years have witnessed a renaissance in the study of social learning in apes. As a result, we are able to review 31 experimental studies from this period in which social learning in chimpanzees, gorillas, and orangutans has been investigated. The principal question framed at the beginning of this era, Do apes ape? has been answered in the affirmative, at least in certain conditions. The more interesting question now is, thus, How do apes ape? Answering this question has engendered richer taxonomies of the range of social-learning processes at work and new methodologies to uncover them. Together, these studies suggest that apes ape by employing a portfolio of alternative social-learning processes in flexibly adaptive ways, in conjunction with nonsocial learning. We conclude by sketching the kind of decision tree that appears to underlie the deployment of these alternatives.

Abstract: It is often assumed that there is more than one kind of learning--or more than one memory system--each of which is specialized for a different function. Yet, the criteria by which the varieties of learning and memory should be distinguished are seldom clear. Learning and memory phenomena can differ from one another across species or situations (and thus be specialized) in a number of different ways. What is needed is a consistent theoretical approach to the whole range of learning phenomena, and one is explored here. Parallels and contrasts in the study of sensory systems illustrate one way to integrate the study of general mechanisms with an appreciation of species-specific adaptations.

Abstract: Domestic chicks are capable of perceiving as a whole objects partly concealed by occluders (“amodal completion”). In previous studies chicks were imprinted on a certain configuration and at test they were required to choose between two alternative versions of it. Using the same paradigm we now investigated the presence of hemispheric differences in amodal completion by testing newborn chicks with one eye temporarily patched. Separate groups of newly hatched chicks were imprinted binocularly: (1) on a square partly occluded by a superimposed bar, (2) on a whole or (3) on an amputated version of the square. At test, in monocular conditions, each chick was presented with a free choice between a complete and an amputated square. In the crucial condition 1, chicks tested with only their left eye in use chose the complete square (like binocular chicks would do); right-eyed chicks, in contrast, tended to choose the amputated square. Similar results were obtained in another group of chicks imprinted binocularly onto a cross (either occluded or amputated in its central part) and required to choose between a complete or an amputated cross. Left-eyed and binocular chicks chose the complete cross, whereas right-eyed chicks did not choose the amputated cross significantly more often. These findings suggest that neural structures fed by the left eye (mainly located in the right hemisphere) are, in the chick, more inclined to a “global” analysis of visual scenes, whereas those fed by the right eye seem to be more inclined to a “featural” analysis of visual scenes.