Object permanence in rhesus monkeys (Macaca mulatta).

We evaluated the performance of 6 adult rhesus monkeys (Macaca mulatta) on object permanence tasks. In Experiment 1, monkeys received search tasks that correspond to Stages 4, 5, and 6 of object permanence. Subjects were successful on tasks of visible displacements (Stages 4 and 5) but failed to find the object in invisible displacements (Stage 6). The monkeys adopted a search strategy of investigating a specific hiding location. In Experiment 2, monkeys were given a second opportunity to find the object if they investigated a location that was part of the displacement on their first search. Subjects relied on the same search strategy identified in Experiment 1. In Experiment 3, the experimenter hid the object in her hand rather than a container. The monkeys failed to recover the object, and individual differences were found in the strategies used. These results suggest that the upper limit of object permanence in rhesus monkeys is Stage 5. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Characteristics of hiding places and the transition to Stage IV performance in object permanence tasks.

Three studies with 53 6–10 mo old infants tested T. G. Bower's (1974, 1975) conjecture that infants' Stage IV object permanence difficulties can be attributed to their interpretation of occlusion as replacement. In Study 1, several types of barriers (upright screen, inverted cup, upright box, cloth) were used in a standard object permanence procedure. Results partially support an order of difficulty predicted by Bower's explanation. Ss were consistently delayed, however, in retrieving objects from inside the upright box. Study 2 investigated the role of previous training and found no effect. When barrier size was varied in Study 3, only the smaller box had the lower successful retrieval rate. Measures of looking and mode of manual search indicated that Ss looked appropriately but did not know how to search inside the small box. An argument is made for standardizing barriers and for measuring looking and searching patterns as well as successful retrieval in object permanence studies. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of self-recognition in the infant.

A hypothesized 5-stage developmental sequence of self-recognition behaviors was tested in 48 infants between 6 and 24 mo of age, and the self-recognition sequence was compared to the development of object permanence. The predicted self-recognition sequence consisted of 5 tasks that Ss performed in front of the mirror, with later-developing tasks requiring the coordination of a larger number of behaviors relating to S's mirror image than earlier-developing tasks. The development of object permanence was assessed with the Uzgiris-Hunt scale, and the object-permanence items were assigned to stages that structurally paralleled the 5 stages of self-recognition. The self-recognition tasks formed an almost perfect Guttman scale, with 46 out of 48 Ss fitting the predicted developmental sequence precisely. This finding thus resolves most of the disagreements in previous research on the development of self-recognition: Previous studies examined different behaviors, which develop at distinct stages in the sequence. Object permanence and self-recognition showed a strong correlation, but there was no consistent relationship between the 2 skills across age groups. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of the use of sound in the search behavior of infants.

Investigated 48 7–9 mo olds' use of sound to guide their search behavior by presenting Ss with standard object-permanence tasks. The same tasks were then presented to Ss but an object was used that made sound as it was being hidden and continued to make sound from its hiding place. Ss were then presented with a task in which a sound-producing object was surreptitiously hidden and then sounded. Ss began to use sound to direct their search in Stage 4. The use of sound to locate the surreptitiously hidden sound-producing object appeared to come earlier than the use of sound to locate objects in displacement tasks; the use of sound to locate objects in displacement tasks was influenced by the complexity of the displacement. Results suggest that the role of sound in the construction of the object is a developing one that continues well into the 2nd yr of life. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive development in kittens (Felis catus): A cross-sectional study of object permanence.

Administered tests of object permanence to 28-, 35-, 48-, and 150-day-old kittens (Felis catus) in order to assess as accurately as possible the developmental level reached at each age group in this Piagetian cognitive capacity. The results indicate that 28-day-old-kittens visually tracked a moving object in their perceptual field (Stage 2); 35-day-olds recovered a hidden object only if they had initiated a search movement at the time of disappearance (Stage 4a); 48- and 150-day-olds mastered multiple visible displacements (Stage 5b). The study showed that the upper limit, Stage 5b, observed in adult cats was reached by Day 48, which indicates a rapid development of object permanence in this species. Results are discussed in relation to object permanence in human babies and in terms of the relevance of object permanence to predatory behavior in the domestic cat. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Le décalage dans le développement de la notion d'objet: Mobilité et immobilité de l'objet.

Studied the development of object–person divergence in infants and the association of this divergence or decalage with the physical properties of the objects. Human subjects: 15 male and female Canadian infants (mean age 9 mo). Ss were given 5 identification tasks using mobile and immobile objects: (1) reorientation; (2) disappearance in place; (3) substitution; (4) disappearance in movement of dissimilar objects; and (5) disappearance in movement of similar objects. Ss were asked to indicate if the object was the same after a spatial-temporal transformation. Responses of the subjects to the identification task were recorded and classified by observers into 6 categories: disinterest, looking at object without moving, picking up the transformed object, picking up the nontransformed object, picking up 2 objects, and reproducing the transformation. The results were analyzed statistically and compared with those of another group of 16 infants performing a permanence test. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Object Permanence After a 24-Hr Delay and Leaving the Locale of Disappearance: The Role of Memory, Space, and Identity.

Fourteen-month-old infants saw an object hidden inside a container and were removed from the disappearance locale for 24 hr. Upon their return, they searched correctly for the hidden object, demonstrating object permanence and long-term memory. Control infants who saw no disappearance did not search. In Experiment 2, infants returned to see the container either in the same or a different room. Performance by room-change infants dropped to baseline levels, suggesting that infant search for hidden objects is guided by numerical identity. Infants seek the individual object that disappeared, which exists in its original location, not in a different room. A new behavior, identity-verifying search, was discovered and quantified. Implications are drawn for memory, spatial understanding, object permanence, and object identity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Responses to hidden persons and things by 5-, 9-, and 16-month-old infants in a visual tracking situation.

To evaluate T. G. Bower's (1974) claim that 5-mo-old infants search for hidden objects on a representational basis, person and toy hiding games were played. Ss were 48 normal infants. Either mother or stranger disappeared and reappeared several times and then the other appeared unexpectedly. The toy game was comparable. The occlusion was simple, and Ss at all ages came to expect the reappearance. Prior research has suggested that infants who search on a representational basis will respond to the trick with surprise or concern and search for the missing object. There was no evidence of search for the missing object. Five-mo-olds did not tend to evidence more surprise or concern on the trick trial than on the preceding one in either game, whereas most 16-mo-olds and some 9-mo-olds did. Differences were not found between the 2 games or the mother and stranger tricks, suggesting that comparable expectations were held about the various objects. The results provide qualified support for Piaget's (1954) view as opposed to Bower's. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Search behaviour of cats (Felis catus) in an invisible displacement test: Cognition and experience.

Two experiments confirmed the hypothesis that cats' search behavior is influenced by their limited cognitive capacity for object permanence as well as by their previous experience with the hiding places of their environment. Exp 1 compared 3 groups of cats in a 5-choice hiding task with visible displacements (VDs). Two groups received VD training and 1 group did not. Exp 2 compared 2 groups of trained cats in the same task, but the hiding places could be discriminated by spatial and visual cues. Results indicate that, like Stage 5 infants, cats rely mainly on immediate perception and are unable to solve problems with invisible displacement. VD training improved their performance but was not sufficient to make them succeed. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of Piagetian object permanence in grey parrot (Psittacus erithacus).

The authors evaluated the ontogenetic performance of a grey parrot (Psittacus erithacus) on object permanence tasks designed for human infants. Testing began when the bird was 8 weeks old, prior to fledging and weaning. Because adult grey parrots understand complex invisible displacements (I. M. Pepperberg & F. A. Kozak, 1986), the authors continued weekly testing until the current subject completed all of I. C. Uzgiris and J. Hunt's (1975) Scale 1 tasks. Stage 6 object permanence with respect to these tasks emerged at 22 weeks, after the bird had fledged but before it was completely weaned. Although the parrot progressed more rapidly overall than other species that have been tested ontogenetically, the subject similarly exhibited a behavioral plateau part way through the study. Additional tests, administered at 8 and 12 months as well as to an adult grey parrot, demonstrated, respectively, that these birds have some representation of a hidden object and understand advanced invisible displacements. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Where do I go next? Intelligent searching by very young children.

A memory-based search task was used to investigate the organization of searching by 24 young children. The task required Ss to remember in what natural location a toy had been hidden. Both an older (25–30 mo of age) and a younger (18–23 mo of age) group of Ss achieved a high level of errorless retrievals. To examine Ss' ability to search differentially as a function of their own level of certainty that they remembered the location of the toy, 2 surprise trials were included in which the toy was hidden as usual but was then moved without the S's knowledge. Ss' search behavior on these surprise trials was compared to their error trials. Both age groups showed greater persistence in their initial search on surprise than on error trials, indicating that their retrieval effort was based on their level of subjective certainty. The 2 age groups displayed different patterns in the subsequent searching that they did: The older, but not the younger, Ss searched differently on surprise and error trials. On surprise trials they searched selectively and intelligently, confining their search primarily to locations that were nearby or in some way related to the place where the toy had actually been hidden. The related searching of the older Ss suggests that they had made intelligent guesses about plausible alternative locations for the missing toy. Data provide evidence of early manifestations of metamemory. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of a looker’s past reliability on infants’ reasoning about beliefs.

We investigated whether 16-month-old infants’ past experience with a person’s gaze reliability influences their expectation about the person’s ability to form beliefs. Infants were first administered a search task in which they observed an experimenter show excitement while looking inside a box that either contained a toy (reliable looker condition) or was empty (unreliable looker condition). The infants were then administered a true belief task in which they watched as the same experimenter hid a toy in 1 of 2 locations. In the test trial, the infants witnessed the experimenter search for the toy in a location that was consistent or inconsistent with her belief about the toy’s location. Results for the true belief task indicated that only the infants in the reliable looker condition looked longer at the incongruent than at the congruent search behavior. These findings are consistent with evidence suggesting that infants encode the identity of agents based on past reliability and implicitly attribute beliefs to others during the 2nd year of life. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rethinking infant knowledge: toward an adaptive process account of successes and failures in object permanence tasks

Infants seem sensitive to hidden objects in habituation tasks at 3.5 months but fail 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.     

Color-object paired associates in deaf and hearing children with and without response competition.

Deaf and hearing Ss, aged 6 and 10, were compared in 2 nonverbally presented paired-associates tasks. One condition used neutral color stimuli unrelated to toy response objects and another condition had colors systematically related to the same objects to provide interfering response competition. Age differences were observed, while task interacted with deafness such that hearing but not deaf Ss were impeded by the interference condition relative to the neutral condition. It was concluded that deaf Ss showed no perceptual rigidity and that covert verbalizations of hearing Ss or experiential poverty in deaf Ss produced the differential task effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Auditory–visual responsiveness in full-term and preterm infants.

Compared older preterm and full-term infants in their response to objects in a dynamic multimodal context. In Study I, 67 12-wk-old full-term infants and 29 preterm infants (mean age 90 days) served as Ss. After familiarization with a silent moving object, full-term Ss recognized the object when it was stationary. When sound accompanied the moving object during familiarization, full-term Ss showed increased attention to the object but no subsequent recognition of that object. Neither high- nor low-risk preterms, at a comparable conceptional age, recognized the objects under any condition, but the low-risk preterms did show greater attention to the moving objects with sound. In Study II, 43 preterm Ss were tested approximately 6 mo after their estimated term date. The performance of the low-risk preterms was the same as that of full-terms; that is, through differential responding, they demonstrated association of an object and sound. In contrast, the high-risk preterms showed no differential looking. Thus both low- and high-risk preterms showed less differential responding than did normal full-terms at 3 mo, but at 6 mo only the high-risk preterms were different from the full-terms. Results suggest that the high-risk preterms are at a disadvantage for learning about the dynamic and multimodal aspects of their environment. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stage 6 object concept in nonhuman primate cognition: A comparison between gorilla (Gorilla gorilla gorilla) and Japanese macaque (Macaca fuscata).

Several investigators have reported the achievement of Stage 6 object concept in a number of species of nonhuman primates. Because Stage 6 object concept implies a capacity for mental representation, such an achievement would demonstrate the presence of a crucial capacity in nonhuman primate cognition. There are, it is suggested, problems in the way nonhuman primates have been tested for Stage 6 object concept (i.e., that the tasks employed could be solved in nonrepresentational ways). The present study attempted to differentiate between representational and nonrepresentational responses in the typical task used for testing Stage 6 object concept (following the invisible displacements of an object). The performance of 2 22-mo-old Ss, a Japanese macaque and a gorilla, was compared. It was found that only the gorilla solved the task with the use of mental representation. The macaque consistently tried to solve the task by employing practical, nonrepresentational strategies. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Selective information use and perseveration in the search behavior of infants and young children

Two experiments examined the early development of selective information use in search. The first experiment tested 9- and 16-month-olds on a modification of Piaget's Stage IV object permanence task. It examined infants' use of information from previous experiences with an object (prior information) and from the most recent hiding (current information) to locate a hidden object. In the second experiment, 2-, 2 1/2-, and 4-year-old children received these same sources of information along with new forms of prior and current information: information about the typical locations of objects (location specificity) and verbal information. No systematic perseveration was observed at 9 months, although previous findings related to perseveration were replicated. Perseveration was found at 16 months, but there was also evidence of selectivity at that age. When errors occurred, they tended to be to the prior location, but they were infrequent in comparison to correct searches at the current location. The preschoolers, while continuing to show perseveration, were more consistently selective than the infants. They also showed considerable generality in extending their selectivity to new sources of information.     

Stages in the development of intentional search by young infants.

Piaget maintained that intentional search is preceded by a phase of transitional search in which infants remove covers but do not show intention to find the hidden object. If there is such a transitional phase, reports of search by infants as young as 5 mo are difficult to evaluate because the type of search has not been identified. Two experiments examined changes in search behavior in 38 infants at age 6, 7, and 8 mo. Exp I revealed that the majority of Ss displayed transitional search before intentional search. Exp II showed that Ss' awareness of the hidden object developed gradually; early transitional search demonstrated minimal awareness, but later transitional search revealed knowledge of the hidden object. An account of search development is given that is in close agreement with Piaget's, and caution is advised in the interpretation of studies with young infants that fail to distinguish different types of search. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive style in two modalities: Vision and audition.

Administered the visual Matching Familiar Figures Sequential Presentation Task (MFF-SPT) and the Auditory Impulsivity Task (AIT), 2 match-to-sample tasks designed to measure cognitive style, to 81 4th graders. A moderate negative correlation was found between errors and latencies on the AIT, thus indicating that longer latency did not always result in better performance. A high negative correlation was found on the MFF-SPT. 55% of the Ss maintained their classification as reflective, impulsive, fast–accurate, or slow–inaccurate across the 2 modalities, providing evidence that the 2 tasks were measuring somewhat different abilities. Ss employed the same search strategy in both modalities. It is suggested that auditory cognitive style be investigated for relationships with reading ability. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of object permanence in food-storing magpies (Pica pica).

The development of object permanence was investigated in black-billed magpies (Pica pica), a food-storing passerine bird. The authors tested the hypothesis that food-storing development should be correlated with object-permanence development and that specific stages of object permanence should be achieved before magpies become independent. As predicted, Piagetian Stages 4 and 5 were reached before independence was achieved, and the ability to represent a fully hidden object (Piagetian Stage 4) emerged by the age when magpies begin to retrieve food. Contrary to psittacine birds and humans, but as in dogs and cats, no "A-not-B error" occurred. Although magpies also mastered 5 of 6 invisible displacement tasks, evidence of Piagetian Stage 6 competence is ambiguous. (PsycINFO Database Record (c) 2010 APA, all rights reserved)