Object and observer motion in the perception of objects by infants

Sixteen-week-old human infants distinguish optical displacements given by their own motion from displacements given by moving objects, and they use only the latter to perceive the unity of partly occluded objects. Optical changes produced by moving the observer around a stationary object produced attentional levels characteristic of stationary observers viewing stationary displays and much lower than those shown by stationary observers viewing moving displays. Real displacements of an object with no subject-relative displacement, produced by moving an object so as to maintain a constant relation to the moving observer, evoked attentional levels that were higher than with stationary displays and more characteristic of attention to moving displays, a finding suggesting detection of the real motion. Previously reported abilities of infants to perceive the unity of partly occluded objects from motion information were found to depend on real object motion rather than on optical displacements in general. The results suggest that object perception depends on registration of the motions of surfaces in the three-dimensional layout.     

Object and spatial representations in the corner enhancement effect

Cole, Gellatly, and Blurton have shown that targets presented adjacent to geometric corners are detected more efficiently than targets presented adjacent to straight edges. In six experiments, we examined how this corner enhancement effect is modulated by corner-of-object representations (i.e., corners that define an object's shape) and local base-level corners that occur as a result of, for instance, overlapping the straight edges of two objects. The results show that the corner phenomenon is greater for corners of object representations than for corners that do not define an object's shape. We also examined whether the corner effect persists within the contour boundaries of an object, as well as on the outside. The results showed that a spatial gradient of attention accompanies the corner effect outside the contour boundaries of an object but that processing within an object is uniform, with no corner effect occurring. We discuss these findings in relation to space-based and object-based theories of attention.     

Sound symbolic naming of novel objects is a graded function

Although linguistic traditions of the last century assumed that there is no link between sound and meaning (i.e., arbitrariness), recent research has established a nonarbitrary relation between sound and meaning (i.e., sound symbolism). For example, some sounds (e.g., /u/ as in took) suggest bigness whereas others (e.g., /i/ as in tiny) suggest smallness. We tested whether sound symbolism only marks contrasts (e.g., small versus big things) or whether it marks object properties in a graded manner (e.g., small, medium, and large things). In two experiments, participants viewed novel objects (i.e., greebles) of varying size and chose the most appropriate name for each object from a list of visually or auditorily presented nonwords that varied incrementally in the number of “large” and “small” phonemes. For instance, “wodolo” contains all large-sounding phonemes, whereas “kitete” contains all small-sounding phonemes. Participants' choices revealed a graded relationship between sound and size: The size of the object linearly predicted the number of large-sounding phonemes in its preferred name. That is, small, medium, and large objects elicited names with increasing numbers of large-sounding phonemes. The results are discussed in relation to cross-modal processing, gesture, and vocal pitch.     

Sound symbolic naming of novel objects is a graded function

Although linguistic traditions of the last century assumed that there is no link between sound and meaning (i.e., arbitrariness), recent research has established a nonarbitrary relation between sound and meaning (i.e., sound symbolism). For example, some sounds (e.g., /u/ as in took) suggest bigness whereas others (e.g., /i/ as in tiny) suggest smallness. We tested whether sound symbolism only marks contrasts (e.g., small versus big things) or whether it marks object properties in a graded manner (e.g., small, medium, and large things). In two experiments, participants viewed novel objects (i.e., greebles) of varying size and chose the most appropriate name for each object from a list of visually or auditorily presented nonwords that varied incrementally in the number of "large" and "small" phonemes. For instance, "wodolo" contains all large-sounding phonemes, whereas "kitete" contains all small-sounding phonemes. Participants' choices revealed a graded relationship between sound and size: The size of the object linearly predicted the number of large-sounding phonemes in its preferred name. That is, small, medium, and large objects elicited names with increasing numbers of large-sounding phonemes. The results are discussed in relation to cross-modal processing, gesture, and vocal pitch.     

Effect of scene complexity on colour constancy with real three-dimensional scenes and objects

The effect of scene complexity on colour constancy was tested with a novel technique in which a virtual image of a real 3-D test object was projected into a real 3-D scene. Observers made discriminations between illuminant and material changes in simple and complex scenes. The extent of colour constancy achieved varied little with either scene structure or test-object colour, suggesting a dominant role of local cues in determining surface-colour judgments.     

Priming problem solving with conceptual processing of relevant objects

In the present study, the author explored the effect of processing relevant information on producing solutions to brief insight problems. She hypothesized that the conceptual processing of objects relevant to the target solution would facilitate that solution relative to unrelated objects or the shallow processing of words. The author also explored the effect of knowledge of the relationship between the initial object-processing task and the problem-solving task. The results showed that participants who conceptually processed objects related to the target solution (Experiment 1), but not those who shallowly processed words related to the target solution (Experiment 2), were more likely to produce the solution relative to the control; and knowledge of the relationship between objects and solutions made no difference in the frequency of target solutions produced. The results of Experiment 3 showed that conceptual processing of an object could prime a nondominant solution for an ambiguously worded problem. Taken together, the results of the studies supported the effect of conceptual processing on facilitating insight in problem solving.     

Object manipulation facilitates kind-based object individuation of shape-similar objects

Five experiments investigated the importance of shape and object manipulation when 12-month-olds were given the task of individuating objects representing exemplars of kinds in an event-mapping design. In Experiments 1 and 2, results of the study from Xu, Carey, and Quint (2004, Experiment 4) were partially replicated, showing that infants were able to individuate two natural-looking exemplars from different categories, but not two exemplars from the same category. In Experiment 3, infants failed to individuate two shape-similar exemplars (from Pauen, 2002a) from different categories. However, Experiment 4 revealed that allowing infants to manipulate objects shortly before the individuation task enabled them to individuate shape-similar objects from different categories. In Experiment 5, allowing object manipulation did not induce infants to individuate natural-looking objects from the same category. These findings suggest that object manipulation facilitates kind-based individuation of shape-similar objects by 12-month-olds.     

Object identification: The mental representation of physical and conceptual attributes

In two experiments, subjects indicated whether two pictures of familiar objects were equivalent. The picture pairs were identical, showed the same object in various perspectives and states, or showed different objects with varying degrees of conceptual relatedness. In Experiment 1, the equivalence criterion for judging the picture pairs was varied between subjects (identity of pictures; conceptual equivalence of objects at subordinate, basic, or superordinate level). The reaction times of the four subject groups suggest that a pictorial stimulus is not always mentally represented in the same way, and that the instructions given determine which attributes of the stimulus are represented. In Experiment 2, the visual similarity of the picture pairs was varied. The results indicate, at least with a basic-level equivalence instruction, that not only perceptual, but also non-perceptual, functional attributes are represented—namely, those that, according to Rosch et al. (1976), are common to the members of a superordinate category.     

Object concepts and action: extracting affordances from objects parts

Two experiments with a part-generation task show that rated salience and production order of parts in artifacts are first predicted by their relevance for canonical actions, but also that they vary, depending on the current situation. In three further experiments participants read sentences describing actions (e.g., 'The woman shares the orange') followed by objects' parts from which it was easy or not to extract affordances (e.g., 'slice' vs. 'pulp'). They had to perform a part verification task or to evaluate whether or not the combination made sense. Parts from which it was easy to derive affordances were processed earlier and the combination was evaluated as the one which made more sense. Overall, results support the view that sensory-motor simulations underlie conceptualization and that concepts are action-based.     

Potential noradrenergic targets for cognitive enhancement in schizophrenia

Substantial evidence suggests that alterations in noradrenergic function contribute to the cognitive impairments of schizophrenia. Activation of post-junctional alpha 2a-adrenergic receptors in the prefrontal cortex by the alpha 2a-selective agonist guanfacine has demonstrated some preliminary benefit in subjects with schizophrenia treated with atypical antipsychotics. alpha 1-adrenergic receptor activity may be less important in mediating the cognitive impairments of schizophrenia. beta-adrenergic receptors may serve as another potential target for cognitive remediation in schizophrenia. However, the potential increase in memory consolidation in schizophrenia patients produced by beta-adrenergic agonists may be outweighed by the impairment in cognitive flexibility and executive functioning produced by beta-adrenergic agonists. Finally, norepinephrine reuptake inhibitors, such as atomoxetine, hold promise as potential cognitive enhancers in schizophrenia because of their ability to indirectly but selectively increase extracellular dopamine concentrations in the prefrontal cortex.