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The present paper examines human hand impedance characteristics, including inertia and viscosity as well as stiffness, in multi-joint arm movements. While a subject maintains a given hand location, small external disturbances are applied to his hand by a manipulandum. The corresponding force-displacement vectors are measured and sampled over time in order(More)
Sound localization in the horizontal plane is mainly determined by interaural time differences (ITD) and interaural level differences (ILD). Both cues result in an estimate of sound source location and in many real-life situations these two cues are roughly congruent. When stimulating listeners with headphones it is possible to counterbalance the two cues,(More)
Delayed matching-to-sample is one of the most frequently employed behavioral tasks for assessing spatial working memory in animals. Although the advantages of the task have been widely acknowledged and it is used in the study of a variety of species, its application to mice has been rare. In the present study, we reported the efficacy of a delayed(More)
When humans process visual stimuli, global information often takes precedence over local information. In contrast, some recent studies have pointed to a local precedence effect in both pigeons and nonhuman primates. In the experiment reported here, we compared the speed of acquisition of two different categorizations of the same four geometric figures. One(More)
Twelve pigeons ( Columba livia) were trained on a go/no-go schedule to discriminate between two kinds of movement patterns of dots, which to human observers appear to be "intentional" and "non-intentional" movements. In experiment 1, the intentional motion stimulus contained one dot (a "wolf") that moved systematically towards another dot as though stalking(More)
Although left-right (L-R) asymmetry is a fundamental feature of higher-order brain function, little is known about how asymmetry defects of the brain affect animal behavior. Previously, we identified structural and functional asymmetries in the circuitry of the mouse hippocampus resulting from the asymmetrical distribution of NMDA receptor GluR ε2 (NR2B)(More)
This paper examines the contribution of stimulus processing to animal logics. In the classic functionalist S-O-R view of learning (and cognition), stimuli provide the raw material to which the organism applies its cognitive processes-its logic, which may be taxon-specific. Stimuli may contribute to the logic of the organism's response, and may do so in(More)
We examined the perceptions of emergent configurations in humans and chimpanzees using a target-localization task. The stimulus display consisted of a target placed among multiple identical distractors. The target and distractors were presented either solely, within congruent contexts in which salient configurations emerge, or within incongruent contexts in(More)
Recent research has suggested that pigeons may have difficulty globally integrating visual information in hierarchically arranged stimuli. To isolate and understand the mechanisms responsible for processing emergent perceptual structure, three pigeons were tested in a two alternative choice task that required the global integration of organized local(More)