The maintenance of apparent luminance of an object.

Results from luminance discriminations with objects defined by apparent motion suggest an object-specific temporal integration of luminance. Further experiments suggested that this integration is weighted to favor the initial display of an object and involves the percept of surface reflectance (lightness). These results are consistent with the object-file metaphor suggested by D. Kahneman, A. Treisman, and B. Gibbs (1992), in which an object's perceived initial surface reflectance is assigned and maintained in an object file. A strategy is proposed in which the intrinsic properties of an object are assumed not to change over time. As intrinsic properties are generally invariant and possibly difficult to compute, this strategy would have the advantage of relatively high accuracy at relatively low computational cost.     

A constraint-based lexicalist account of the subject/object attachment preference

When a noun phrase could either be the object of the preceding verb or the subject of a new clause or a sentence complement, readers and listeners show a strong preference to parse the noun phrase as the object of the verb. This can result in clear garden paths for sentences such asThe student read the book was stolen andWhile the student read the book was stolen. Even when the verb does not permit a noun phrase complement, soem processing difficulty is still found. This has led some theorists to propose models in which initial attachments are lexically blind, with lexical information subsequently used as a filter to evaluate and revise initial analyses. In contrast, we show that these results emerge naturally from constraint-based lexicalist models. We present a modeling experiment with a simple recurrent network that was trained to predict upcoming complements for a sample of verbs taken from the Penn Treebank corpus. The model exhibits an boject bias and it aloo shows effects of verb frequency which are similar to those found in the psycholinguistic literature.     

The value hypothesis and acquisition of preference in concurrent chains

Experiment 1 compared the acquisition of initial- and terminal-link responding in concurrent chains. The terminal-link schedules were fixed interval (FI) 10 sec and FI 20 sec, but some presentations were analogous to no-food trials in the peak procedure, lasting 60 sec with no reinforcement delivery. Pigeons completed a series of reversals in which the schedules signaled by the terminal-link stimuli (red and green on the center key) were changed. Acquisition of temporal control of terminal-link responding (as measured by peak location on no-food trials) was more rapid than acquisition of preference in the initial links. Experiment 2 compared acquisition in concurrent chains, using the typical procedure in which the terminal-link schedules are changed with a novel arrangement in which the initial-link key assignments were changed while the terminal-link schedules remained the same. Acquisition of preference was faster in the latter condition, in which the terminal-link stimulus-reinforcer relations were preserved. These experiments provide the first acquisition data that support the view that initial-link preference is determined by the values of the terminal-link stimuli.     

Incorporation of an invasive object

The author discusses the experience of 'being invaded' that is sometimes communicated by certain severely disturbed patients. The complaint can sometimes be couched in terms of bodily suffering and such patients may state that they have the experience of a 'foreign body' inside. It is suggested that these patients have suffered severe early failure of containment of their projections, while at the same time they have incorporated primitive characteristics of the object that have been powerfully projected into them. An object that invades in this way, it is suggested, experiences a compulsive need to expel unbearable states of mind using others as a repository. The infant incorporates these violent projections as part of his own mental representational system, and normal identifi cation processes are disrupted. There follows impairment of the development of the sense of self. Clinical examples of how the invasive experience manifests itself in the analytic setting and in the transference and countertransference are presented. It is argued that this highly complex form of early subject-object interaction (prior to the differentiation of psyche-soma) is more likely to be found in severely narcissistically disturbed individuals. Some refl ections on the origins of invasive phenomena are given.     

Hand-use preference for reaching and object manipulation in 6- through 13-month-old infants

Validity, reliability, and stability of separate assessment of hand-use preferences for reaching, object manipulation, and complementary bimanual action were determined for 6 through 13 month-old male and female infants. Only hand-use preferences for complementary bimanual action varied with age. Females had more distinct hand-use preference than males but only for object manipulation. Comparison of hand-use preference among these different sensorimotor skills can provide a richer evaluation of infant handedness status required for systematic study of the development of neuropsychological functions during infancy.     

The space of an object: object attention alters the spatial gradient in the surround

Although object-based attention enhances perceptual processing of information appearing within the boundaries of a selected object, little is known about the consequences for information in the object's surround. The authors show that distance from an attended object's center of mass determines reaction time (RT) to targets in the surround. Of 2 targets in the surround, both equidistant from a cue, the target closer to the center of mass was detected faster. Moreover, RT was shown to be a linear function of distance from the center of mass of a fixed, attended object, and changes to the shape of the object and its center of mass predictably altered RT. Object-based attention leads to a pattern of facilitation in the surround that may contribute to the organization of visual scenes.     

Selective attention to the parts of an object

Recent empirical results suggest that there is a decrement in dividing attention between two objects in a scene compared with focusing attention on a single object. However, objects can be made of individual parts. Is there a decrement for dividing attention across different parts of a single object? We addressed this question in two experiments. In Experiment 1, we demonstrated that attention can exhibit part-based selection—that is, the subjects were more accurate in reporting two attributes from the same part of an object than they were in reporting attributes from different parts of an object. In Experiment 2, we demonstrated that part-based attentional decrements occurred simultaneously with object-based attentional decrements. The results from Experiment 2 demonstrated that part-based attention is evident at the same time as objects are processed as coherent wholes. Our results imply that there is an attentional mechanism that can select either objects or their parts.     

Selective attention and the perception of an attended nontarget object

Although many theories of attention assume that attending to an object results in the processing of all its feature dimensions, there has been no direct evidence that the irrelevant dimensions of an attended nontarget object are encoded. This article explores factors that modulate such processing. In 6 experiments, participants made a speeded response to a probe preceded by a prime that varied in 2 dimensions. Their reaction times to the probe were influenced by the response compatibility between the relevant and irrelevant dimensions of the prime. Furthermore, the effect was observed only when attention was directed to a nonlocation object feature and when participants' reaction times were relatively long. These results suggest that the effect of attention on a nontarget object is more complex than was previously understood.     

See an object,hear an object file: Object correspondence transcends sensory modality

An important task of perceptual processing is to parse incoming information into distinct units and to keep track of those units over time as the same, persisting representations. Within the study of visual perception, maintaining such persisting object representations is helped by “object files”—episodic representations that store (and update) information about objects' properties and track objects over time and motion via spatiotemporal information. Although object files are typically discussed as visual, here we demonstrate that object–file correspondence can be computed across sensory modalities. An object file can be initially formed with visual input and later accessed with corresponding auditory information, suggesting that object files may be able to operate at a multimodal level of perceptual processing.     

Development of hand preference in the Colorado Adoption Project

A longitudinal study of the development of hand preference in 152 adopted and 120 nonadopted (control) infants measured in natural behavioral situations at both 12 and 24 mo. of age is reported. Significant developmental trends were observed for both increasing strength and direction of handedness. Less than 10% of the infants exhibited a clear preference at 12 mo. of age, whereas about 30% were lateralized at 24 mo., with more boys than girls being left-handed. In contrast, over 90% of the parents of these children (both biological and adoptive parents of the adopted children and parents of the nonadopted children) were lateralized. Perhaps because so few infants were lateralized at either age, parent-offspring resemblances were inconsistent and the number of significant parent/child correlations was about that expected on the basis of chance alone.     

Scaling reward value with demand curves versus preference tests

In Experiment 1, six capuchins lifted a weight during a 10-min session to receive a food piece. Across conditions, the weight was increased across six different amounts for three different food types. The number of food pieces obtained as a function of the weight lifted was fitted by a demand equation that is hypothesized to quantify food value. For most subjects, this analysis showed that the three food types differed little in value. In Experiment 2, these monkeys were given pairwise choices among these food types. In 13 of 18 comparisons, preferences at least equaled a 3-to-1 ratio; in seven comparisons, preference was absolute. There was no relation between values based on degree of preference versus values based on the demand equation. When choices in the present report were compared to similar data with these subjects from another study, between-study lability in preference emerged. This outcome contrasts with the finding in demand analysis that test–retest reliability is high. We attribute the unreliability and extreme assignment of value based on preference tests to high substitutability between foods. We suggest use of demand analysis instead of preference tests for studies that compare the values of different foods. A better strategy might be to avoid manipulating value by using different foods. Where possible, value should be manipulated by varying amounts of a single food type because, over an appropriate range, more food is consistently more valuable than less. Such an approach would be immune to problems in between-food substitutability.     

Hand preference and its flexibility according to the position of the object: a study in cercopithecines examining spontaneous behaviour and an experimental task (the Bishop QHP task)

The extant literature on manual laterality in non-human primates is inconclusive, plagued by inconsistent or contradictory findings and by disturbing methodological issues (e.g. uncontrolled influential factors, comparability issues). The present study examined hand preference and its flexibility in 15 red-capped mangabeys (C. t. torquatus) and 13 Campbell's monkeys (C. c. campbelli), two species that differ in their degree of arboreality. We investigated the influence of the spatial position of the object on hand preference for reaching. We considered spontaneous behaviour (reaching for food during daily feeding) and an experimental task: the QHP task. The QHP is a task that is used in humans. This is a simple reaching task that involves high spatial constraints on hand use. In our study, the subject had to reach for items that were placed on a semi-circle in front of it on five positions, including in the centre position, in the ipsilateral space and in the contralateral space. We assessed hand preference for reaching in front (baseline condition), and we examined how this preference changed when reaching in lateral positions. For reaching in front, about half of the subjects were lateralized and no group-level bias occurred, for both spontaneous and experimental conditions. When considering reaching in the lateral positions, we observed that the position of the object influenced hand use: individuals used the hand that was closest to the object. The results are discussed in relation to previous findings in humans and in non-human primates and regarding theories on handedness and flexibility of hand preference.     

Appearance of an illusory object in the blind spot

We report a phenomenon showing new aspects of perceptual filling-in at the blind spot. When two and three discs were presented below the blind spot, observers perceived them as three and four discs, respectively, but when they were presented in the nasal visual field as a control, the perceived numbers were veridical. The phenomenon demonstrates that the visual system produces an illusory object in the blind spot even when the inducing objects presented on only one side of the blind spot are clearly discrete and countable.     

The consistency of the items of an activity preference blank

Results of an experiment to obtain data on the consistency of the items of two forms of an Activity Preference Blank are presented. Both Form I and Form II, which was a revised edition of Form I, were administered twice, so consistency data are available for both forms. A sub-item is said to be consistent if a high proportion of men marked it the same way,M for preferred Most andL for preferred Least, on both administrations of the test. The data of the experiment were investigated to see what happens to the consistency of sub-items when the items are changed in context, when the number of sub-items in an item is reduced, and when the time-interval between the administration and the re-administration of the test is increased. The author also gives data on the consistency of the responses made to particular combinations of sub-items and data on item consistency when all sub-item combinations are taken into consideration.     

Children's preference for body or external object on a task requiring transposition and discrimination of right-left relations.

First graders were tested on trials requiring the discrimination and transposition of right-left relations, with stimuli similar to (dolls) or different from (toy planes) the body. On an initial series of training and practice trials children were allowed to respond to body and external objects as referents providing right-left cues. A later series of test trials was then used to determine the referent the child actually preferred. Results of the test trials indicated that 24 children tested with the dolls preferred the body as referent, while 24 children tested with planes preferred the external referent. The results were interpreted as suggesting two alternative systems through which children develop an understanding of right-left relations and possibly other concepts as well.     

The group as an object in the cultural field

This paper illuminates the interplay between group and individual processes by exploring members' notions of the group itself. What members hold in common about the "group" is understood as an object in the cultural field, which is a particular kind of transitional phenomenon (Winnicott). The paper connects this notion to Bion's concept of "basic assumptions," and describes members' motivations for creating the "group" as well as its role in the psychotherapy group. The object in the cultural field is then further elaborated in its more general role in the relation between the individual and the group, which leads to a consideration of psychotherapy groups in terms of their value in facilitating living in the social world.