Object permanence

Last updated

Object permanence is the understanding that whether an object can be sensed has no effect on whether it continues to exist (in the mind). This is a fundamental concept studied in the field of developmental psychology, the subfield of psychology that addresses the development of young children's social and mental capacities. There is not yet scientific consensus on when the understanding of object permanence emerges in human development.

Contents

Jean Piaget, the Swiss psychologist who first studied object permanence in infants, argued that it is one of an infant's most important accomplishments, as, without this concept, objects would have no separate, permanent existence. In Piaget's theory of cognitive development, infants develop this understanding by the end of the "sensorimotor stage", which lasts from birth to about two years of age. [1] Piaget thought that an infant's perception and understanding of the world depended on their motor development, which was required for the infant to link visual, tactile and motor representations of objects. According to this view, it is through touching and handling objects that infants develop object permanence. [2]

Early research

Developmental psychologist Jean Piaget conducted experiments that collected behavioral tests on infants. Piaget studied object permanence by observing infants' reactions when a favorite object or toy was presented and then was covered with a blanket or removed from sight. Object permanence is considered to be one of the earliest methods for evaluating working memory. [3] An infant that has started to develop object permanence might reach for the toy or try to grab the blanket off the toy. Infants that have not yet developed this might appear confused. [4] Piaget interpreted these behavioral signs as evidence of a belief that the object had ceased to exist. Reactions of most infants that had already started developing object permanence were of frustration because they knew it existed, but did not know where it was. However, the reaction of infants that had not yet started developing object permanence was more oblivious. If an infant searched for the object, it was assumed that they believed it continued to exist. [1]

Piaget concluded that some infants are too young to understand object permanence. A lack of object permanence can lead to A-not-B errors, where children reach for a thing at a place where it should not be. Older infants are less likely to make the A-not-B error because they are able to understand the concept of object permanence more than younger infants. However, researchers have found that A-not-B errors do not always show up consistently. [5] They concluded that this type of error might be due to a failure in memory or the fact that infants usually tend to repeat a previous motor behavior. [1]

Stages

Peek-a-boo is a prime example of an object permanence test. US Navy 100406-N-7478G-346 Operations Specialist 2nd Class Reginald Harlmon and Electronics Technician 3rd Class Maura Schulze play peek-a-boo with a child in the Children's Ward at Hospital Likas.jpg
Peek-a-boo is a prime example of an object permanence test.

In Piaget's formulation, there are six stages of object permanence. [7] These are:

  1. 0–1 months: Reflex schema stage – Babies learn how the body can move and work. Vision is blurred and attention spans remain short through infancy. They are not particularly aware of objects to know they have disappeared from sight. However, babies as young as seven minutes old prefer to look at faces. The three primary achievements of this stage are sucking, visual tracking, and hand closure. [8]
  2. 1–4 months: Primary circular reactions – Babies notice objects and start following their movements. They continue to look where an object was, but for only a few moments. They 'discover' their eyes, arms, hands and feet in the course of acting on objects. This stage is marked by responses to familiar images and sounds (including parent's face) and anticipatory responses to familiar events (such as opening the mouth for a spoon). The infant's actions become less reflexive and intentionality emerges. [8]
  3. 4–8 months: Secondary circular reactions – Babies will reach for an object that is partially hidden, indicating knowledge that the whole object is still there. If an object is completely hidden, however, the baby makes no attempt to retrieve it. The infant learns to coordinate vision and comprehension. Actions are intentional, but the child tends to repeat similar actions on the same object. Novel behaviors are not yet imitated. [8]
  4. 8–12 months: Coordination of secondary circular reactions – This is deemed the most important for the cognitive development of the child. At this stage the child understands causality and is goal-directed. The very earliest understanding of object permanence emerges, as the child is now able to retrieve an object when its concealment is observed. This stage is associated with the classic A-not-B error. After successfully retrieving a hidden object at one location (A), the child fails to retrieve it at a second location (B). [8]
  5. 12–18 months: Tertiary circular reaction – The child gains means-end knowledge and is able to solve new problems. The child is now able to retrieve an object when it is hidden several times within their view, but cannot locate it when it is outside their perceptual field. [8]
  6. 18–24 months: Invention of new means through mental combination – The child fully understands object permanence. They will not fall for A-not-B errors. Also, a baby is able to understand the concept of items that are hidden in containers. If a toy is hidden in a matchbox then the matchbox put under a pillow and then, without the child seeing, the toy is slipped out of the matchbox and the matchbox then given to the child, the child will look under the pillow upon discovery that it is not in the matchbox. The child is able to develop a mental image, hold it in mind, and manipulate it to solve problems, including object permanence problems that are not based solely on perception. The child can now reason about where the object may be when invisible displacement occurs. [8]

Contradicting evidence

In more recent years, the original Piagetian object permanence account has been challenged by a series of infant studies suggesting that much younger infants do have a clear sense that objects exist even when out of sight. Bower showed object permanence in 3-month-olds. [9] [10] This goes against Piaget's coordination of secondary circular reactions stage because infants are not supposed to understand that a completely hidden object still exists until they are eight to twelve months old. The two studies below demonstrate this idea.

The first study showed infants a toy car that moved down an inclined track, disappeared behind a screen, and then reemerged at the other end, still on the track. The researchers created a "possible event" where a toy mouse was placed behind the tracks but was hidden by the screen as the car rolled by. Then, researchers created an "impossible event". In this situation, the toy mouse was placed on the tracks but was secretly removed after the screen was lowered so that the car seemed to go through the mouse. The infants were surprised by the impossible event, which suggests they remembered not only that the toy mouse still existed (object permanence) but also its location. Also in the 1991 study the researchers used an experiment involving two differently sized carrots (one tall and one short) in order to test the infants’ response when the carrots would be moved behind a short wall. [10] The wall was specifically designed to make the short carrot disappear, as well as tested the infants for habituation patterns on the disappearance of the tall carrot behind the wall (impossible event). [10] Infants as young as 3+1⁄2 months displayed greater stimulation toward the impossible event and much more habituation at the possible event. The same was true of the tall carrot in the second experiment. This research suggests that infants understand more about objects earlier than Piaget proposed. [1]

There are primarily four challenges to Piaget's framework:

  1. Whether or not infants without disabilities actually demonstrate object permanence earlier than Piaget claimed. [11]
  2. There is disagreement about the relative levels of difficulty posed by the use of various types of covers and by different object positions. [12]
  3. Controversy concerns whether or not perception of object permanence can be achieved or measured without the motor acts that Piaget regarded as essential. [13]
  4. The nature of inferences that can be made from the A-not-B error has been challenged. Studies that have contributed to this discussion have examined the contribution of memory limitations, difficulty with spatial localization, and difficulty in inhibiting the motor act of reaching to location A on the A-not-B error. [10]

One criticism of Piaget's theory is that culture and education exert stronger influences on a child's development than Piaget maintained. These factors depend on how much practice their culture provides in developmental processes, such as conversational skills. [1]

In animals

Experiments in non-human primates suggest that monkeys can track the displacement of invisible targets, [14] [15] that invisible displacement is represented in the prefrontal cortex, [16] [17] [18] and that development of the frontal cortex is linked to the acquisition of object permanence. [19] Various evidence from human infants is consistent with this. For example, formation of synapses in the frontal cortex peaks during human infancy, [20] and recent experiments using near infrared spectroscopy to gather neuroimaging data from infants suggests that activity in the frontal cortex is associated with successful completion of object permanence tasks. [21]

However, many other types of animals have been shown to have the ability for object permanence. These include dogs, cats, and a few species of birds such as the carrion crow, Eurasian jays and food-storing magpies. Dogs are able to reach a level of object permanence that allows them to find food after it has been hidden beneath one of two cups and rotated 90°. [22] Similarly, cats are able to understand object permanence but not to the same extent that dogs can. Cats fail to understand that if they see something go into an apparatus in one direction that it will still be there if the cat tries to enter from another direction. [23] However, while cats did not seem to be quite as good at this "invisible displacement test" as dogs are, it is hard to say whether their poorer performance is a true reflection of their abilities or just due to the way in which they have been tested. [24] A longitudinal study found that carrion crows' ability developed gradually, albeit with slight changes in the order of mastery compared to human infants. There was only one task, task 15, that the crows were not able to master. The crows showed perseverative searches at a previously rewarded location (the so-called "A-not-B error"). They mastered visible rotational displacements consistently, but failed at more complex invisible rotational displacements. [25] Another study tested the comparison of how long it took food-storing magpies to develop the object permanence necessary for them to be able to live independently. [26] The research suggests that these magpies followed a very similar pattern as human infants while they were developing.

In artificial agents

It has been shown that artificial intelligent agents can be trained to exhibit object permanence. [27] [28] Building such agents revealed an interesting structure. The object permanence task involves several visual and reasoning components, where the most important ones are to detect a visible object, to learn how it moves and to reason about its movement even when it is not visible. Shamsian et al [27] found that object permanence was achieved when the agent had two separate time-sensitive modules, one that tracks visible objects, and a second that decides "what to track" when one object occludes or contains the target. Object permanence has further been shown to apply to videos "in the wild". [28]

Recent studies

One of the areas of focus on object permanence has been how physical disabilities (blindness, cerebral palsy and deafness) and intellectual disabilities (Down syndrome, etc.) affect the development of object permanence. In a study that was performed in 1975–76, the result shows that the only area where children with intellectual disabilities performed more weakly than children without disabilities was along the lines of social interaction. Other tasks, such as imitation and causality tasks, were performed more weakly by the children without disabilities. However, object permanence was still acquired similarly because it was not related to social interaction.

Some psychologists believe that "while object permanence alone may not predict communicative achievement, object permanence along with several other sensorimotor milestones, plays a critical role in, and interacts with, the communicative development of children with severe disabilities". [29] This was observed in 2006, in a study recognizing where the full mastery of object permanence is one of the milestones that ties into a child's ability to engage in mental representation. Along with the relationship with language acquisition, object permanence is also related to the achievement of self-recognition. This same study also focused specifically on the effects that Down syndrome has on object permanence. They found that the reason why the children that participated were so successful in acquiring object permanence, was due to their social strength in imitation. Along with imitation being a potential factor in the success, another factor that could impact children with Down syndrome could also be the willingness of the child to cooperate. [30]

Other, more recent studies suggest that the idea of object permanence may not be an innate function of young children. While, in reference to Piaget's theory, it has been established that young children develop object permanence as they age, the question arises: does this occur because of a particular perception that already existed within the minds of these young children? Is object permanence really an inbred response to the neural pathways developing in young minds? Studies suggest that a multitude of variables may be responsible for the development of object permanence rather than a natural talent of infants. Evidence suggests that infants use a variety of cues while studying an object and their perception of the object's permanence can be tested without physically hiding the object. Rather, the object is occluded, slightly obstructed, from the infants view and they are left only other visual cues, such as examining the object from different trajectories. It was also found that the longer an infant focuses on an object may be due to detected discontinuities in their visual field, or the flow of events, with which the infant has become familiar. [31]

See also

Related Research Articles

<span class="mw-page-title-main">Developmental psychology</span> Scientific study of psychological changes in humans over the course of their lives

Developmental psychology is the scientific study of how and why humans grow, change, and adapt across the course of their lives. Originally concerned with infants and children, the field has expanded to include adolescence, adult development, aging, and the entire lifespan. Developmental psychologists aim to explain how thinking, feeling, and behaviors change throughout life. This field examines change across three major dimensions, which are physical development, cognitive development, and social emotional development. Within these three dimensions are a broad range of topics including motor skills, executive functions, moral understanding, language acquisition, social change, personality, emotional development, self-concept, and identity formation.

<span class="mw-page-title-main">Jean Piaget</span> Swiss psychologist, biologist, logician, philosopher and academic (1896–1980)

Jean William Fritz Piaget was a Swiss psychologist known for his work on child development. Piaget's theory of cognitive development and epistemological view are together called genetic epistemology.

<span class="mw-page-title-main">Imaginary friend</span> Psychological and social phenomenon

Imaginary friends are a psychological and a social phenomenon where a friendship or other interpersonal relationship takes place in the imagination rather than physical reality.

In psychology, theory of mind refers to the capacity to understand other people by ascribing mental states to them. A theory of mind includes the knowledge that others' beliefs, desires, intentions, emotions, and thoughts may be different from one's own. Possessing a functional theory of mind is crucial for success in everyday human social interactions. People utilise a theory of mind when analyzing, judging, and inferring others' behaviors. The discovery and development of theory of mind primarily came from studies done with animals and infants. Factors including drug and alcohol consumption, language development, cognitive delays, age, and culture can affect a person's capacity to display theory of mind. Having a theory of mind is similar to but not identical with having the capacity for empathy or sympathy.

<span class="mw-page-title-main">Piaget's theory of cognitive development</span> Theory that discusses human intelligence from an epistemological perspective

Piaget's theory of cognitive development, or his genetic epistemology, is a comprehensive theory about the nature and development of human intelligence. It was originated by the Swiss developmental psychologist Jean Piaget (1896–1980). The theory deals with the nature of knowledge itself and how humans gradually come to acquire, construct, and use it. Piaget's theory is mainly known as a developmental stage theory.

Cognitive development is a field of study in neuroscience and psychology focusing on a child's development in terms of information processing, conceptual resources, perceptual skill, language learning, and other aspects of the developed adult brain and cognitive psychology. Qualitative differences between how a child processes their waking experience and how an adult processes their waking experience are acknowledged. Cognitive development is defined as the emergence of the ability to consciously cognize, understand, and articulate their understanding in adult terms. Cognitive development is how a person perceives, thinks, and gains understanding of their world through the relations of genetic and learning factors. There are four stages to cognitive information development. They are, reasoning, intelligence, language, and memory. These stages start when the baby is about 18 months old, they play with toys, listen to their parents speak, they watch TV, anything that catches their attention helps build their cognitive development.

Egocentrism is the inability to differentiate between self and other. More specifically, it is the inability to accurately assume or understand any perspective other than one's own. Egocentrism is found across the life span: in infancy, early childhood, adolescence, and adulthood. Although egocentric behaviors are less prominent in adulthood, the existence of some forms of egocentrism in adulthood indicates that overcoming egocentrism may be a lifelong development that never achieves completion. Adults appear to be less egocentric than children because they are faster to correct from an initially egocentric perspective than children, not because they are less likely to initially adopt an egocentric perspective.

The A-not-B error is an incomplete or absent schema of object permanence, normally observed during the sensorimotor stage of Jean Piaget's Theory of Cognitive Development.

<span class="mw-page-title-main">Peekaboo</span> Game played primarily with babies

Peekaboo is a form of play played with an infant. To play, one player hides their face, pops back into the view of the other, and says Peekaboo!, sometimes followed by I see you! There are many variations: for example, where trees are involved, "Hiding behind that tree!" is sometimes added. Another variation involves saying "Where's the baby?" while the face is covered and "There's the baby!" when uncovering the face.

In psychology, centration is the tendency to focus on one salient aspect of a situation and neglect other, possibly relevant aspects. Introduced by the Swiss psychologist Jean Piaget through his cognitive-developmental stage theory, centration is a behaviour often demonstrated in the preoperational stage. Piaget claimed that egocentrism, a common element responsible for preoperational children's unsystematic thinking, was causal to centration. Research on centration has primarily been made by Piaget, shown through his conservation tasks, while contemporary researchers have expanded on his ideas.

Early childhood is a stage in human development following infancy and preceding middle childhood. It generally includes toddlerhood and some time afterward. Play age is an unspecific designation approximately within the scope of early childhood.

<span class="mw-page-title-main">Executive functions</span> Cognitive processes necessary for control of behavior

In cognitive science and neuropsychology, executive functions are a set of cognitive processes that are necessary for the cognitive control of behavior: selecting and successfully monitoring behaviors that facilitate the attainment of chosen goals. Executive functions include basic cognitive processes such as attentional control, cognitive inhibition, inhibitory control, working memory, and cognitive flexibility. Higher-order executive functions require the simultaneous use of multiple basic executive functions and include planning and fluid intelligence.

<span class="mw-page-title-main">Adele Diamond</span> Neuroscientist

Adele Dorothy Diamond is a professor of neuroscience at the University of British Columbia, where she is currently a Tier 1 Canada Research Chair in Developmental Cognitive Neuroscience. One of the pioneers in the field of developmental cognitive neuroscience, Diamond researches how executive functions are affected by biological and environmental factors, especially in children. Her discoveries have improved treatment for disorders such as phenylketonuria and attention-deficit hyperactivity disorder, and they have impacted early education.

<span class="mw-page-title-main">Child development</span> Developmental change in children

Child development involves the biological, psychological and emotional changes that occur in human beings between birth and the conclusion of adolescence.

<span class="mw-page-title-main">Joint attention</span> When two people focus on something at once

Joint attention or shared attention is the shared focus of two individuals on an object. It is achieved when one individual alerts another to an object by means of eye-gazing, pointing or other verbal or non-verbal indications. An individual gazes at another individual, points to an object and then returns their gaze to the individual. Scaife and Bruner were the first researchers to present a cross-sectional description of children's ability to follow eye gaze in 1975. They found that most eight- to ten-month-old children followed a line of regard, and that all 11- to 14-month-old children did so. This early research showed it was possible for an adult to bring certain objects in the environment to an infant's attention using eye gaze.

Infant cognitive development is the first stage of human cognitive development, in the youngest children. The academic field of infant cognitive development studies of how psychological processes involved in thinking and knowing develop in young children. Information is acquired in a number of ways including through sight, sound, touch, taste, smell and language, all of which require processing by our cognitive system. However, cognition begins through social bonds between children and caregivers, which gradually increase through the essential motive force of Shared intentionality. The notion of Shared intentionality describes unaware processes during social learning at the onset of life when organisms in the simple reflexes substage of the sensorimotor stage of cognitive development do not maintain communication via the sensory system.

Renée Baillargeon is a Canadian American research psychologist. An Alumni Distinguished Professor of Psychology at the University of Illinois Urbana-Champaign. Baillargeon specializes in the development of cognition in infancy.

<span class="mw-page-title-main">Attentional control</span> Individuals capacity to choose what they pay attention to and what they ignore

Attentional control, colloquially referred to as concentration, refers to an individual's capacity to choose what they pay attention to and what they ignore. It is also known as endogenous attention or executive attention. In lay terms, attentional control can be described as an individual's ability to concentrate. Primarily mediated by the frontal areas of the brain including the anterior cingulate cortex, attentional control is thought to be closely related to other executive functions such as working memory.

Representational insight is the ability to detect and mentally represent the relation between a symbol and its referent. Whether or not a child gains this insight depends on the similarity between the symbol and its referent, the level of information provided about the relationship between the symbol and the referent, and a child's prior experience with symbols. An essential part of representational insight is dual representation or the existence of multiple mental representations of a single symbolic entity. Judy DeLoache coined this term after conducting many studies in which young children would watch an experimenter hide a toy in a model room and were then asked to retrieve a similar, but larger toy from a larger room.

Perspective-taking is the act of perceiving a situation or understanding a concept from an alternative point of view, such as that of another individual.

References

  1. 1 2 3 4 5 Santrock, John W. (2008). A topical approach to life-span development (4 ed.). New York City: McGraw-Hill. ISBN   978-0-07-3133768.
  2. ↑ Bremner, JG (1994). Infancy (2 ed.). Blackwell. ISBN   978-0-631-18466-9.
  3. ↑ Lowe, Jean; Peggy MacLean; Michele Shaffer; Kristi Watterberg (2009). "Early Working Memory in Children Born With Extremely Low Birth Weight: Assessed by Object Permanence". Journal of Child. 24 (4): 410–415. doi:10.1177/0883073808324533. PMC   3071030 . PMID   19339284. ProQuest   621922851.
  4. ↑ Ellis-Christensen, Tricia. "What Is Object Permanence?". Conjecture Corporation. Retrieved 2011-11-21.
  5. ↑ Sophian, C.; Yengo, L. (1985). "Infants' understanding of visible displacements". Developmental Psychology. 21 (6): 932–941. doi:10.1037/0012-1649.21.6.932.
  6. ↑ Kitajima, Yoshio; Kumoi, Miyoshi; Koike, Toshihide (1998). "Developmental changes of anticipatory heart rate responses in human infants". Japanese Journal of Physiological Psychology and Psychophysiology. 16 (2): 93–100. doi: 10.5674/jjppp1983.16.93 . ProQuest   619539004.
  7. ↑ Piaget, Jean (1977). Gruber, Howard E.; Vonèche, J. Jacques. (eds.). The essential Piaget. London: Routledge and K. Paul. ISBN   978-0710087782. OCLC   3813049.
  8. 1 2 3 4 5 6 Anderson, John E. (1955). "Review of The construction of reality in the child". Psychological Bulletin. 52 (6): 526–8. doi:10.1037/h0039645.
  9. ↑ Bower, T. G. R. (1974). Development in infancy. San Francisco: Freeman.
  10. 1 2 3 4 Baillargeon, R.; DeVos, J. (1991). "Object permanence in young infants: further evidence". Child Development. 62 (6): 1227–1246. doi:10.2307/1130803. JSTOR   1130803. PMID   1786712.
  11. ↑ Káldy, Zsuzsa; Sigala, Natasha (2004). "The neural mechanisms of object working memory: What is where in the infant brain?". Neuroscience and Biobehavioral Reviews. 28 (2): 113–121. doi:10.1016/j.neubiorev.2004.01.002. PMID   15172760. S2CID   12730891. ProQuest   620420191.
  12. ↑ Lucas, Thomas; Uzgiris, Ina C. (1977). "Spatial factors in the development of the object concept". Developmental Psychology. 13 (5): 492–500. doi:10.1037/0012-1649.13.5.492. ProQuest   616220376.
  13. ↑ Moore, M. Keith; Meltzoff, Andrew N. (2004). "Object Permanence After a 24-Hr Delay and Leaving the Locale of Disappearance: The Role of Memory, Space, and Identity". Developmental Psychology. 40 (4): 606–620. doi:10.1037/0012-1649.40.4.606. PMC   1398789 . PMID   15238047. ProQuest   620426719.
  14. ↑ Filion, C. M.; Washburn, D. A.; Gulledge, J. P. (1996). "Can monkeys (Macaca mulatta) represent invisible displacement?". J. Comp. Psychol. 110 (4): 386–395. doi:10.1037/0735-7036.110.4.386. hdl: 2060/19970020679 . PMID   8956508.
  15. ↑ Churchland MM, Chou IH, Lisberger SG (2003). "Evidence for object permanence in the smooth-pursuit eye movements of monkeys". J. Neurophysiol. 90 (4): 2205–2218. doi:10.1152/jn.01056.2002. PMC   2581619 . PMID   12815015.
  16. ↑ Barborica A, Ferrera VP (2003). "Estimating invisible target speed from neuronal activity in monkey frontal eye field". Nature Neuroscience. 6 (1): 66–74. doi:10.1038/nn990. PMID   12483216. S2CID   2288571.
  17. ↑ Xiao Q, Barborica A, Ferrera VP (2007). "Modulation of visual responses in macaque frontal eye field during covert tracking of invisible targets". Cereb Cortex. 17 (4): 918–928. doi: 10.1093/cercor/bhl002 . PMID   16723405.
  18. ↑ Barborica A, Ferrera VP (2004). "Modification of saccades evoked by electrical stimulation of macaque frontal eye field during invisible target tracking". J. Neurosci. 24 (13): 3260–3267. doi:10.1523/JNEUROSCI.4702-03.2004. PMC   6730017 . PMID   15056705.
  19. ↑ Diamond, A.; Goldman-Rakic, P. (1989). "Comparison of human infants and rhesus monkeys on Piaget's AB task: Evidence for dependence on dorsolateral prefrontal cortex". Experimental Brain Research. 74 (1): 24–40. doi:10.1007/bf00248277. PMID   2924839. S2CID   2310409.
  20. ↑ Neville, H. J.; Bavelier, D. (2000). "Specificity and Plasticity in Neurocognitive Development in Humans". In Gazzaniga, M. S. (ed.). The New Cognitive Neurosciences . MIT Press. pp.  1259–1270. ISBN   9780262071956.
  21. ↑ Baird, AA; Kagan, J.; Gaudette, T.; Walz, K. A.; Hershlag, N.; Boas, D. A. (2002). "Frontal Lobe Activation during Object Permanence:Data from Near-Infrared Spectroscopy". NeuroImage. 16 (4): 1120–1126. doi:10.1006/nimg.2002.1170. PMID   12202098. S2CID   15630444.
  22. ↑ Miller, Holly; Gibson, Cassie D.; Vaughan, Aubrey; Rayburn-Reeves, Rebecca; Zentall, Thomas R. (2009). "Object permanence in dogs: Invisible displacement in a rotation task". Psychonomic Bulletin & Review. 16 (1): 150–155. doi: 10.3758/pbr.16.1.150 . PMID   19145026. ProQuest   622272578.
  23. ↑ Doré, François Y. (1986). "Object permanence in adult cats (Felis catus)". Journal of Comparative Psychology. 100 (4): 340–347. doi:10.1037/0735-7036.100.4.340. ProQuest   617246971.
  24. ↑ Muth, Felicity. "What's Going On in Your Cat's Head?". Scientific American Blog Network. Retrieved 2017-10-10.
  25. ↑ Hoffmann, Almut; Rüttler, Vanessa; Nieder, Andreas (2011). "Ontogeny of object permanence and object tracking in the carrion crow, Corvus corone". Animal Behaviour. 82 (2): 359–359–367. doi:10.1016/j.anbehav.2011.05.012. S2CID   51913693. ProQuest   885701151.
  26. ↑ Pollok, Bettina; Prior, Helmut; Güntürkün, Onur (2000). "Development of object permanence in food-storing magpies (Pica pica)". Journal of Comparative Psychology. 114 (2): 148–157. doi:10.1037/0735-7036.114.2.148. PMID   10890586. ProQuest   619461015.
  27. 1 2 Shamsian, Aviv; Kleinfeld, Ofri; Globerson, Amir; Chechik, Gal (2020). "Learning Object Permanence from Video" (PDF). European Conference on Computer Vision (ECCV). arXiv: 2003.10469 .
  28. 1 2 Tomakov, Pavel (2021). "Learning to Track with Object Permanence" (PDF). International Conference in Computer Vision (ICCV). arXiv: 2103.14258 .
  29. ↑ Kahn, J. V. (May 1976). "Utility of the Uzgiris and Hunt seales of sensorimotor development with severely and profoundly retarded children". American Journal of Mental Deficiency. 80 (6): 663–665. ISSN   0002-9351. PMID   961731.
  30. ↑ Wright, Ingram; Lewis, Vicky; Collis, Glyn M. (June 2006). "Imitation and representational development in young children with Down syndrome". British Journal of Developmental Psychology. 24 (2): 429–450. doi:10.1348/026151005x51257. ISSN   0261-510X.
  31. ↑ Bremner, J. G.; Slater, A. M.; Johnson, S. P. (2015). "Perception of object persistence: the origins of object permanence in infancy" (PDF). Child Development Perspectives. 9 (1): 7–13. doi:10.1111/cdep.12098.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.