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A variety of cell types exist in the temporal cortex providing high-level visual descriptions of bodies and their movements. We have investigated the sensitivity of such cells to different viewing conditions to determine the frame(s) of reference utilized in processing. The responses of the majority of cells in the upper bank of the superior temporal sulcus (areas TPO and PGa) found to be sensitive to static and dynamic information about the body were selective for one perspective view (e.g. right profile, reaching right or walking left). These cells can be considered to provide viewer-centred descriptions because they depend on the observer's vantage point. Viewer-centred descriptions could be used in guiding behaviour. They could also be used as an intermediate step for establishing view-independent responses of other cell types which responded to many or all perspective views selectively of the same object (e.g. head) or movement. These cells have the properties of object-centred descriptions, where the object viewed provides the frame of reference for describing the disposition of object parts and movements (e.g. head on top of shoulders, reaching across the body, walking forward 'following the nose'). For some cells in the lower bank of the superior temporal sulcus (area TEa) the responses to body movements were related to the object or goal of the movements (e.g. reaching for or walking towards a specific place). This goal-centred sensitivity to interaction allowed the cells to be selectively activated in situations where human subjects would attribute causal and intentional relationships.

In 4 experiments, it was shown that hills appear steeper to people who are encumbered by wearing a heavy backpack (Experiment 1), are fatigued (Experiment 2), are of low physical fitness (Experiment 3), or are elderly and/or in declining health (Experiment 4). Visually guided actions are unaffected by these manipulations of physiological potential. Although dissociable, the awareness and action systems were also shown to be interconnected. Recalibration of the transformation relating awareness and actions was found to occur over long-term changes in physiological potential (fitness level, age, and health) but not with transitory changes (fatigue and load). Findings are discussed in terms of a time-dependent coordination between the separate systems that control explicit visual awareness and visually guided action. In conscious awareness, the apparent slant of hills is greatly exaggerated. For example, 5 ° hills appear to be about 20°, and 10 ° ones look to be about 30 ° (Proffitt, Bhalla, Gossweiler, & Midgett, 1995). Be that as it may, people are not especially prone to stumble whenever the terrain over

What are the brain and cognitive systems that allow humans to play baseball, compute square roots, cook soufflés, or navigate the Tokyo subways? It may seem that studies of human infants and of non-human animals will tell us little about these abilities, because only educated, enculturated human adults engage in organized games, formal mathematics, gourmet cooking, or map-reading. In this chapter, we argue against this seemingly sensible conclusion. When human adults exhibit complex, uniquely human, culture-specific skills, they draw on a set of psychological and neural mechanisms with two distinctive properties: they evolved before humanity and thus are shared with other animals, and they emerge early in human development and thus are common to infants, children, and adults. These core knowledge systems form the building blocks for uniquely human skills. Without them we wouldn’t be able to learn about different kinds of games, mathematics, cooking, or maps. To understand what is special about human intelligence, therefore, we must study both the core knowledge systems on which it rests and the mechanisms by which these systems are orchestrated to permit new kinds of concepts and cognitive processes. What is core knowledge? A wealth of research on non-human primates and on human

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We studied the visual features that support efficient entry-level object recognition by measuring naming latencies for different views of artifacts and four-legged animals that were shown as shaded images or as silhouettes. Experiment 1 revealed important differences in performance for the two renderings. Although three-quarter views of animals were recognized relatively quickly when shaded, they were not recognized quickly when presented as silhouettes. The same was true of artifacts when they were seen from the back. Experiment 2 used idealobserver analyses to confirm that these effects could not be accounted for by differences in the intrinsic complexity of the stimuli. Together, these findings indicate that, for human observers, the shape of an object's bounding contour does not serve as a direct visual coding of the object, although it might be used as a first index into visual memory. These results also indicate that shading is important for recognizing objects in certain views...

Abstract: Humans can effortlessly understand a lot of what is going on in other peoples ’ minds. Understanding the neural basis of this capacity has proven quite difficult. Since the discovery of mirror neurons, a number of successful experiments have approached the question of how we understand the actions of others from the perspective of sharing their actions. Recently we have demonstrated that a similar logic may apply to understanding the emotions and sensations of others. Here, we therefore review evidence that a single mechanism (shared circuits) applies to actions, sensations and emotions: witnessing the actions, sensations and emotions of other individuals activates brain areas normally involved in performing the same actions and feeling the same sensations and emotions. We propose that these circuits, shared between the first (I do, I feel) and third person perspective (seeing her do, seeing her feel) translate the vision and sound of what other people do and feel into the language of the observers own actions and feelings. This translation could help understand the actions and feelings of others by providing intuitive insights into their inner life. We propose a mechanism for the development of shared circuits on the basis of Hebbian learning, and underline that shared circuits could integrate with more cognitive functions during social cognitions.

Previous studies suggest that there are "canonical" viewpoints from which objects are identified most readily. Object naming has been the primary objective measure used to assess view canonicality, but this task has not proven adequate in distinguishing the many explanations of this phenomenon that have been offered. We examine object naming (Experiment 1a) and name verification (Experiments 1b and 2) to better understand the origin and nature of canonical view effects in recognition. In the name verification experiments, observers read an object name and then viewed an image of an object and decided as quickly as possible whether the image matched the name. The stimuli were images of 3D computer models of seven common objects. Each object was rendered from one canonical viewpoint (determined in a separate experimentby Blanz, Tarr, Bülthoff, & Vetter, 1996) and two noncanonical viewpoints. Observers named the objects faster in canonical views, but performance was not affected by viewpoint...

this paper, we use the spike count as our neural code. This assumption INTRODUCTION greatly simplifies our calculations, although in principle everything we do here could be applied to coding schemes that Neurons in different regions of the visual system encode include temporal variations.

Infants seem sensitive to hidden objects in habituation tasks at 3.5 months but fall to retrieve hidden objects until 8 months. The authors first consider principle-based accounts of these successes and failures, in which early successes imply knowledge of principles and failures are attributed to ancillary deficits. One account is that infants younger than 8 months have the object permanence principle but lack means-ends abilities. To test this, 7-month-olds were trained on means-ends behaviors and were tested on retrieval of visible and occluded toys. Means-ends demands were the same, yet infants made more toy-guided retrievals in the visible case. The authors offer an adaptive process account in which knowledge is graded and embedded in specific behavioral processes. Simulation models that learn gradually to represent occluded objects show how this approach can account for success and failure in object permanence tasks without assuming principles and ancillary deficits.