Perceptual Development

Two experiments examined postural responses of 3-to 6-year-old children to visual informarion for oscillation. In Experiment 1, children saw oscillations of the surround, with these movements ranging in frequency between 0.2 and 0.8 Hz. Analyses of anterior-posterior postural sway revealed that, similar to previous developmental investigations, the frequency of sway matched the frequency of oscillations. Analyses of sway amplitude and timing, however, revealed patterns of results more in keeping with research on adults. Experiment 2 extended these findings, presenting oscillations in which the frequency changed during the trial. Analyses of anterior--posterior sway revealed that sway frequency matched both speeds of movement. In contrast, amplitude and timing measures were again in line with adult data. These results suggest that the postural sway of children contains both adultlike and nonadultlike parameters of balance control.

Introduces the role of neuromaturational and dynamical systems theory in child development and ensuing adult movement behavior. Highlights the work of physical therapist, Irmgard Bartenieff (1900 - 1982) and occupational therapist Bonnie Bainbridge Cohen and the development of the somatic movement systems:  Bartenieff Fundamentals and Body-Mind Centering, respectively.  Compares and contrasts these two systems of human movement analysis and their perspectives in intervention with children and adults.  Shares Dr. Eddy's unique blend of these two systems in Dynamic Embodiment Somatic Movement Therapy.  Provides charts of different views of body organization and neuro-developmental organization in embryological and infant motor planning, as well as the reflex theory related to adult performance.  Also includes additional charts from the pedagogy of colleague Rachelle Tsachor.

In Flourish, the positive psychologist Martin Seligman (2011) identifies five commonly recognized factors that are characteristic of human flourishing or wellbeing: (1) “positive emotion,” (2) “relationships,” (3) “engagement,” (4) “achievement,” and (5) “meaning” (p. 24). Although there is no settled set of necessary and sufficient conditions neatly circumscribing the bounds of human flourishing (Seligman, 2011), we would mostly likely consider a person that possessed high levels of these five factors as paradigmatic or prototypical of human flourishing. Accordingly, if we wanted to go about the practical task of actually increasing our level of wellbeing, we ought to do so by focusing on practically increasing the levels of the five factors that are characteristic of wellbeing. If, for instance, an activity such as musical engagement can be shown to positively influence each or all of these five factors, this would be compelling evidence that an activity such as musical engagement can positively contribute to one’s living a flourishing life. I’m of the belief that psychological research can and should be used, not only to identify and diagnose maladaptive psychological states, but identify and promote adaptive psychological states as well. In this article I advance the hypothesis and provide supporting evidence for the claim that musical engagement can positively contribute to one’s living a flourishing life. Since there has not yet been a substantive and up-to-date investigation of the possible role of music in contributing to one’s living a flourishing life, the purpose of this article is to conduct this investigation, thereby bridging the gap and stimulating discussion between the psychology of music and the psychology of wellbeing.

https://doi.org/10.3389/fpsyg.2011.00393
https://doctorcroom.com/croom-2012b

Perceptual narrowing reflects the effects of early experience and contributes in key ways to perceptual and cognitive development. Previous studies have found that unisensory perceptual sensitivity in young infants is broadly tuned such that they can discriminate native as well as non-native sensory inputs but that it is more narrowly tuned in older infants such that they only respond to native inputs. Recently, my coworkers and I discovered that multisensory perceptual sensitivity narrows as well. The present article reviews this new evidence in the general context of multisensory perceptual development and the effects of early experience. Together, the evidence on unisensory and multisensory narrowing shows that early experience shapes the emergence of perceptual specialization and expertise. ß 2014 Wiley Periodicals, Inc. Dev Psychobiol

Ecological validity has typically been taken to refer to whether or not one can generalize from observed behavior in the laboratory to natural behavior in the world. Although common in current discussions of research, the idea of ecological validity has a long history in psychological thought. A brief historical examination of this idea reveals that concerns with ecological validity are evident in multiple dimensions of experimental work, including the nature of the experimental setting, the stimuli under investigation, and the observer's response employed as the measure. One problem with this multidimensionality, however, is that no explicit criteria have been offered for applying this concept to an evaluation of research. One consequence of this problem is that concerns with ecological validity can be raised in most experimental situations. This article includes a discussion of some demands of ecological validity and the nature of these different dimensions, as well as a critical evaluation of research on the development of mobility with respect to these constraints.

Míg a korábbi években az autizmus pszichológiai elméletei és vizsgálatai a kognitív-kommunikációs eltérésekre helyezték a hangsúlyt, az utóbbi években előtérbe kerültek az autizmus spektrumzavarral élők érzékelési-észlelési nehézségei. Tanulmányunkban azokkal az érzékelési eltérésekkel foglalkozunk, amelyek sajátossá teszik az észlelt valóságot ezen személyek számára. Vizsgálatunkban tipikus fejlődésmenetű és autizmus spektrumzavarral élő kisgyermekek szenzoros profilját hasonlítottuk össze Bogdashina (2003) Érzékelési Állapotfelmérő Kérdőívének (Sensory Profil Checklist Revised) felhasználásával.

The question of space is twofold: seen from the point of view of its creator and from the point of view of its user. In addition, in between is the question of perception, of space perception. How do we relate to space? How do we read it? What is its meaning? Is perception a cultural issue or just a biological function? In order to formulate an opinion on these issues, we have to start at the very root of the problem, namely the development of the perceptual process.

Thus, based on the extensive studies undertaken by Jean Piaget, the paper intends to detail the action of acquiring and developing the perceptual process, linking it to the different stages of growth. The second part of the paper tries to look into the similarities between the structure of the social environment and its relation to space, and the way in which the same type of structure can be extracted from or applied to the children’s games of “hide and seek”. Its complexity, its many variables make it a very interesting process of spatial learning. Consequently, the game is reproducing and exercising the features, the meanings of the environment and the way in which the child should relate to similar real life situations.

The aim of this theoretical quest is to emphasise the importance of games in developing and nurturing a proper way of perceiving and relating to the environment and to its social and cultural particularities.

Do perceiving subjects represent kind properties in the content of their conscious visual experience when they see and recognize instances of those natural kinds? In Part 1 of my thesis I clarify this question, in Part 2 I answer it, and in Part 3 I raise a problem for previous answers. Part 1 conceives of conscious experience in an internalist way, and the unified conscious episode does not exclude having beliefs about what one sees.

Purpose. During development, the presence of strabismus and anisometropia frequently leads to amblyopia, a visual disorder characterized by interocular acuity differences. Although additional deficits in contrast sensitivity, crowding (the impaired recognition of closely spaced objects), and stereoacuity are common, the relationship between these abilities is unclear.

Methods. We measured the covariation between these four abilities in children 4 to 9 years of age (n = 72) with strabismus, anisometropia, or mixed strabismus/anisometropia, and unaffected controls. Children reported the orientation of a target (a modified “Pac-Man,” similar to Landolt-C stimuli) using four “ghosts” as references. Using a modified staircase procedure we measured threshold size (acuity), contrast detection, foveal crowding (the minimum separation between target and ghost-flankers supporting accurate identification), and stereoacuity (with random-dot stereogram ghosts).

Results. Group averages revealed significant interocular differences (IODs) in acuity for all three clinical groups (0.2–0.3 log minutes), and significant crowding IODs for the strabismic and mixed groups (0.6 and 0.4°, respectively). Nonetheless, crowding IODs were correlated with acuity IODs in all four groups (r values between 0.43 and 0.59 and P < 0.05; P = 0.07 in the mixed group). Similarly, the occurrence of stereo-blindness (most common in strabismic and mixed groups) was associated with a significant increase in IODs for both acuity and crowding (each P < 0.05). No correlations were found with contrast detection.

Conclusions. Our results demonstrate an association between IODs in acuity and crowding and, furthermore, between these IODs and the presence of stereo-vision. We suggest that the deficits derived from strabismus and anisometropia lay along a continuum with abilities observed during normal development.

Two experiments explored 5-month-old infants' recognition of selfmovement in the context of imperfect contingencies between felt and seen movement. Previous work has shown that infants can discriminate a display of another child's movements from an on-line video display of their own movements, even when featural information is removed. These earlier findings were extended by demonstrating self versus other discrimination when the visual information for movement was an unrelated object (a fluorescent mobile) directly attached to the child's leg, thus producing imperfect spatial and temporal contingency information. In contrast, intermodal recognition failed when the mobile was indirectly attached to infants' legs, thus eliminating spatial contingencies altogether and further weakening temporal contingencies. Together, these studies reveal that even imperfect contingency information can drive intermodal perception, given appropriate levels of spatial and temporal contingency information. ß 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 387-398, 2007.

In this article the problem of perception is highlighted from a philosophical, physiological and psychological point of view. The essay (second update) is followed by a list of publications, journals and websites about perception. The author would be delighted to receive comments. He can be contacted at j[underscore]kuijper[at]online[dot]nl.

In this introduction to the special issue on Action and perception in infancy, we summarize recent arguments of Milner and Goodale for a dissociation between vision for action and vision for perception in adults. We propose that this dissociation is probably present from birth, and further that vision for action and vision for perception follow different developmental trajectories. Based on this framework, we discern four themes of interest for infancy research (i.e., information and action, exploration and action, information and perception, and the interaction between action and perception) and introduce the contributions of the special issue accordingly.

According to conventional wisdom, multisensory development is a progressive process that results in the growth and proliferation of perceptual skills. We review new findings indicating that a regressive processperceptual narrowingalso contributes in critical ways to perceptual development. These new data reveal that young infants are able to integrate non-native faces and vocalizations, that this broad multisensory perceptual tuning is present at birth, and that this tuning narrows by the end of the first year of life, leaving infants with the ability to integrate only socio-ecologicallyrelevant multisensory signals. This narrowing process forces us to reconsider the traditional progressive theories of multisensory development and opens up several new evolutionary questions as well.

Two experiments investigated 9-month-old infants' abilities to recognize the correspondence between an actual three-dimensional (3D) object and its twodimensional (2D) representation, looking specifically at representations that did not literally depict the actual object: schematic line drawings. In Experiment 1, infants habituated to a line drawing of either a doll or a sheep and were then tested with the actual objects themselves. Infants habituated to the sheep drawing recovered to the unfamiliar but not the familiar object, showing a novelty preference. Infants habituated to the doll drawing, however, recovered to both familiar and unfamiliar objects, failing to show any preference between the two. In Experiment 2, infants habituated to the 3D objects and were then tested with the 2D line drawings. In this case, both groups of infants showed a preference only for the novel displays. Together these findings demonstrate that 9-month-old infants recognize the correspondence between 3D objects and their 2D representations, even when these representations are not literal copies of the objects themselves.

Tool-use is specialized in humans, and juvenile humans show much more prolific and prodigious tool-use than other juvenile primates. Nonhuman primates possess many of the basic motor and behavioral capacities needed for manual tool-use: perceptual-motor specialization, sociocultural practices and interactions, and abstract conceptualization of kinds of functions, both real and imagined. These traits jointly contribute to the human specialization for tool-using. In particular, from 2 to 5 years of age children develop: (i) more refined motor routines for interacting with a variety of objects, (ii) a deeper under- standing and awareness of the cultural context of object-use practices, and (iii) a cognitive facility to represent potential dynamic human–object interactions. The last trait, which has received little attention in recent years, is defined as the ability to form abstract (i.e., generalizable to novel contexts) representations of kinds of functions, even with relatively little training or instruction. This trait might depend not only on extensive tool-using expe- rience but also on developing cognitive abilities, including a variety of cognitive flexibility: specifically, imagistic memory for event sequences incorporating causal inferences about mechanical effects. Final speculations point to a possible network of neural systems that might contribute to the cognitive capacity that includes sensorimotor, sensory integration, and prefrontal cortical resources and interconnections.

Perception of the ordinal position of a sequence element is critical to many cognitive and motor functions. Here, the prediction that this ability is based on a domain-general perceptual mechanism and, thus, that it emerges prior to the emergence of language was tested. Infants were habituated with sequences of moving/sounding objects and then tested for the ability to perceive the invariant ordinal position of a single element (Experiment 1) or the invariant relative ordinal position of two adjacent elements (Experiment 2). Experiment 1 tested 4-and 6-month-old infants and showed that 4-month-old infants focused on conflicting low-level sequence statistics and, therefore, failed to detect the ordinal position information, but that 6-month-old infants ignored the statistics and detected the ordinal position information. Experiment 2 tested 6-, 8-, and 10-month-old infants and showed that only 10-month-old infants detected relative ordinal position information and that they could only accomplish this with the aid of concurrent statistical cues. Together, these results indicate that a domain-general ability to detect ordinal position information emerges during infancy and that its initial emergence is preceded and facilitated by the earlier emergence of the ability to detect statistical cues.

In this theoretical work, we treat behavioral and perceptual issues on an equal footing and examine the emergence of mutually exclusive behavioral patterns and perceptual variables during infant development from the perspective of multistable competitive dynamic systems. Accordingly, behavioral modes and modes of perception compete with each other for activation. One and only one mode survives the mode-mode competition, which accounts for the incompatibility of modes being considered. However, the winning behavioral or perceptual state is not predefined. Rather, we argue that during particular stages of maturation multiple modes coexist for the same set of developmental, body-scaled, and environmental parameters or constraints. The winning behavioral or perceptual state depends on these parameters as well as on initial conditions as operationalized in terms of previously performed behaviors or utilized perceptual stimuli. We give explicit examples of our approach and address the emergence of two-handed grasping and catching movements and the emergence of monocular and binocular vision during infant development. In particular, we propose that the emergence of midline crossing movements in 3-to 6-month-old infants involves two independent but interaction control parameters: a body-scaled and a developmental one. Likewise, we argue that the onset of binocularity in infants involves two independent but interaction control parameters: a developmental and an environmental one. ß 2010 Wiley Periodicals, Inc. Dev Psychobiol 52: 352-371, 2010.

A rapidly approaching object provides information about the object's approach and how imminent a collision is. Prospective control when responding to a looming virtual object approaching on a direct collision course was studied longitudinally in 10 infants aged 5/6 and 12/13 months. Different characteristics of the looming-related visual evoked potential (VEP) responses from infants' brain electrical recordings (EEG) were explored and compared between the infants at these different ages. The aim of this study was to find evidence for infant brain electrical responses coherent with a looming stimulus approaching the infant under three different accelerations. It was also investigated whether the use of different timing strategies to estimate the loom's time-to-collision would produce differences in the EEG recordings. The results showed that the timing and the duration of the VEP responses differed with age. At the age of 5/6 months, infants showed VEP peaks earlier in the looming se

In this study, the Perceptual Skills Scale (PSS) was developed to determine the sensory, cognitive and emotional perception skills of primary school children. For the validity and reliability study of the scale, data were collected between April and May 2019 from seven primary schools that differ in socioeconomic terms in a city center in NorthWestern Turkey; and a total of 643 parents were reached. Within the scope of the validity study of the PSS, content (scope) validity and structure validity analyses were performed. The Hambleton method was used for content (scope) validity, as well as referring to expert opinions. The construct validity of the scale was examined by looking at the confirmatory factor analysis and the item-total correlations. It was determined that item-total test correlations varied between 0.181 and 0.597. In the confirmatory factor analysis, comparative fit index (CFI) was found as 0.99; goodness of fit index (GFI) as 0.89; normed fit index (NFI) as 0.91; and relative fit index (RFI) as 0.90. Cronbach Alpha analysis was performed for the reliability of the scale and it was determined that the Cronbach Alpha coefficients varied between 0.730 and 0.844. As a result of the validity-reliability analysis, it was seen that the scale is valid and reliable.

Three experiments investigated 4-, 6-, and 8-month-old infants' perception of the audible, visible, and combined attributes of bimodally specified syllables. Ninety-six infants in each experiment were habituated to a person mouthing and uttering a syllable and then tested for detection of changes of either the audible, visible, or combined attributes of the syllable. When the attributes of the syllable were produced in an adult-directed manner, all three age groups discriminated the audible and bimodal attribute changes but only the 8-month-olds discriminated the visible one. When the difference between the familiar and novel attributes of the syllable was enhanced by testing with a novel syllable produced in an infant-directed manner, all three age groups detected all three types of changes. Finally, to test the possible role of audiovisual synchrony in responsiveness, infants were tested with an asynchronous syllable spoken either by the same person or by a novel person following habituation to a synchronous syllable. Results suggested that at four months infants attended primarily to the featural information, at six months primarily to the asynchrony, and at eight months to both features independently. These results help identify some of the important dimensions of multimodal speech during early development.

This study examined 4-to 10-month-old infants' perception of audio-visual (A-V) temporal synchrony cues in the presence or absence of rhythmic pattern cues. Experiment 1 established that infants of all ages could successfully discriminate between two different audiovisual rhythmic events. Experiment 2 showed that only 10-month-old infants detected a desynchronization of the auditory and visual components of a rhythmical event. Experiment 3 showed that 4-to 8-month-old infants could detect A-V desynchronization but only when the audiovisual event was nonrhythmic. These results show that initially in development infants attend to the overall temporal structure of rhythmic audiovisual events but that later in development they become capable of perceiving the embedded intersensory temporal synchrony relations as well.

This study investigated perception of audiovisual sequences in 3-and 4-month-old infants. Infants were habituated to sequences consisting of moving/sounding or looming/sounding objects and then tested for their ability to detect changes in the order of the objects, sounds, or both. Results showed that 3-month-olds perceived the order of 3-element sequences and that 4-month-olds perceived the order of 3-and 4-element sequences. In addition, results indicated that perception of moving sequences was more robust than of looming ones and that detection of order differences was not based on primacy cues. The current results show that perception of multisensory sequences and their structure emerges early in development, and a preliminary model of the development of sequence perception is offered.

A rapidly approaching object provides information about the object’s approach and how imminent a collision is. Prospective control when responding to a looming virtual object approaching on a direct collision course was studied longitudinally in ten infants aged 5/6 and 12/13 months. Different characteristics of the looming-related VEP responses from infants’ brain electrical recordings (EEG) were explored and compared between the infants at these different ages. The aim of this study was to find evidence for infant brain electrical responses coherent with a looming stimulus approaching the infant under three different accelerations. It was also investigated whether the use of different timing strategies to estimate the loom’s time-to-collision would produce differences in the EEG recordings. The results showed that the timing and the duration of the VEP responses differed with age. At the age of 5/6 months, infants showed VEP peaks earlier in the looming sequence and VEP responses with longer duration than when they were 12/13 months old. Results from the timing-strategy analysis showed that with age, four infants shifted from a less efficient timing strategy involving the loom’s velocity to the more efficient strategy involving the loom’s time-to-collision. Further, it was found that peak VEP activation in the investigated areas propagated across the cortex, showing the highest observed activation in the occipital area at the age of 5/6 months, whereas the parietal area showed the highest activation when the infants were 12/13 months. The decrease in processing time together with a peak VEP response closer to the loom’s time-to-collision indicate a developmental trend in infants’ prediction of an object’s time-to-collision. This developmental trend is further substantiated by the shift from a less efficient to a more efficient timing strategy and by evidence of propagated peak VEP activation towards higher information processing areas in the visual pathway with age. As infants grow older and become more mobile one of the underlying causes of the developmental trend found in our study could be due to an increase in locomotor experience. More follow-up research is needed to investigate the relation between behavioural development and changes in brain activity associated with infants’ perception of looming motion.

The A-not-B error , which occurs when infants search perseveratively on reversal trials in a delayed-response task, is one of the most widely studied phenomena in developmental psychology. Nonetheless, the effect of A-trial experience on the probability and magnitude of this error remains unclear. In this study, 9-month-old infants were tested at location A until they searched correctly on 1, 6, or 11 A trials. Results revealed an effect of A trials on the proportion of infants who erred on the first B trial, and on the number of errors prior to a correct search at B (i.e., the error run). These effects were asymptotic, or U-shaped, consistent with a dual-process model according to which A-trial experience increases habit strength but also provides opportunities for reflection on task structure.

Background: Understanding the evolutionary origins of a phenotype requires understanding the relationship between ontogenetic and phylogenetic processes. Human infants have been shown to undergo a process of perceptual narrowing during their first year of life, whereby their intersensory ability to match the faces and voices of another species declines as they get older. We investigated the evolutionary origins of this behavioral phenotype by examining whether or not this developmental process occurs in non-human primates as well.

Three experiments investigated perception of audio-visual (A-V) speech synchrony in 4-to 10-month-old infants. Experiments 1 and 2 used a convergent-operations approach by habituating infants to an audiovisually synchronous syllable (Experiment 1) and then testing for detection of increasing degrees of A-V asynchrony (366, 500, and 666 ms) or by habituating infants to a detectably asynchronous syllable (666 ms; Experiment 2) and then testing for detection of decreasing degrees of asynchrony (500, 366, and 0 ms). Following habituation to the synchronous syllable, infants detected only the largest A-V asynchrony (0 ms vs. 666 ms), whereas following habituation to the asynchronous syllable, infants detected the largest asynchrony (666 ms vs. 0 ms) as well as a smaller one (666 ms vs. 366 ms). Experiment 3 investigated the underlying mechanism of A-V asynchrony detection and indicated that responsiveness was based on a sensitivity to stimulus-energy onsets rather than the dynamic correlation between acoustic and visible utterance attributes. These findings demonstrated that infant perception of A-V speech synchrony is subject to the effects of short-term experience and that it is driven by a low-level, domain-general mechanism.

Purpose. During development, the presence of strabismus and anisometropia frequently leads to amblyopia, a visual disorder characterized by interocular acuity differences. Although additional deficits in contrast sensitivity, crowding (the impaired recognition of closely spaced objects), and stereoacuity are common, the relationship between these abilities is unclear. Methods. We measured the covariation between these four abilities in children 4 to 9 years of age (n= 72) with strabismus, anisometropia, or mixed strabismus/ ...

In the McGurk effect, perceptual identification of auditory speech syllables is influenced by simultaneous presentation of discrepant visible speech syllables. This effect has been found in subjects of different ages and with various native language backgrounds. But no McGurk tests have been conducted with prelinguistic infants. In the present series of experiments, 5-month-old English-exposed infants were tested for the McGurk effect. Infants were first gaze-habituated to an audiovisual Ivai. Two different dishabituation stimuli were then presented: audio /hal-visual Ivai (perceived by adults as Iva!), and audio Idal-visual Ivai (perceived by adults as Ida!). The infants showed generalization from the audiovisual Ivai to the audio /ba/-vtsual Ivai stimulus but not to the audio Idal-visual Ivai stimulus. Follow-up experiments revealed that these generalization differences were not due to a general preference for the audio Idal-visual Ivai stimulus or to the auditory similarity of /ba/ to Ivai relative to Idal. These results suggest that the infants were visually influenced in the same way as Englishspeaking adults are visually influenced.

Une séance d'expérimentation collective est menée par un groupe de chercheurs en sciences humaines et sociales de l'UTC sur un système de suppléance perceptive (Tactos). L'expérience s'appelle « Soleil ». Ce document en propose une narration. Il mêle compte-rendu ethnographique, récit en première personne, transcription littérale des échanges, captures d'images, analyses épistémologiques et afterthoughts des acteurs. Il y est question d'attention conjointe, de recherche technologique en SHS, de minimalisme, de perception partagée de l'infini, de micromonde artificiel, de design d'expérience, de technoscience et de constitutivité technique. On y voit les chercheurs théoriser, détricoter les théories, expérimenter, se concentrer, se déconcentrer, converger, diverger, s'aider à comprendre, protester, ne plus rien comprendre, contester le dispositif, tenir bon, hésiter, gesticuler, dessiner, se comprendre avec les mains, et produire une nouvelle question pour de nouveaux dispositifs. Le récit assume l'hétérogénéité. Contrairement à un article scientifique classique, il ne cherche pas à ordonner les multiples modalités et temporalités d'observation et d'interaction sous une synthèse théorique qui gommerait les aspérités, les incohérences, les divergences et les hésitations de la recherche en train de se faire. Mais il ne conclut pas pour autant au pur constat d'hétérogénéité. Au contraire, il montre comment une compréhension et un sens partagé se constituent à travers une praxis collective qui inclut le dispositif expérimental. Ou, comment, en recherche technologique, monter en réflexivité requiert de s'enfoncer dans le monde des fonctionnements techniques.

Two experiments investigated 9-month-old infants’ abilities to recognize the correspondence between an actual three-dimensional (3D) object and its two-dimensional (2D) representation, looking specifically at representations that did not literally depict the actual object: schematic line drawings. In Experiment 1, infants habituated to a line drawing of either a doll or a sheep and were then tested with the actual objects themselves. Infants habituated to the sheep drawing recovered to the unfamiliar but not the familiar object, showing a novelty preference. Infants habituated to the doll drawing, however, recovered to both familiar and unfamiliar objects, failing to show any preference between the two. In Experiment 2, infants habituated to the 3D objects and were then tested with the 2D line drawings. In this case, both groups of infants showed a preference only for the novel displays. Together these findings demonstrate that 9-month-old infants recognize the correspondence between 3D objects and their 2D representations, even when these representations are not literal copies of the objects themselves.

Do 9-month-old infants motorically simulate actions they perceive others perform? Two experiments tested whether action observation, like overt reaching, is sufficient to elicit the Piagetian A-not-B error. Infants recovered a toy hidden at location A or observed an experimenter recover the toy. After the toy was hidden at location B, infants in both conditions perseverated in reaching to A, demonstrating that active search by the infant is not necessary for the A-not-B error. Consistent with prior research, infants displayed an ipsilateral bias when reaching, the so-called mysterious midline barrier. A similar ipsilateral bias was also observed depending on the manner in which the experimenter reached; infants perseverated following observation of ipsi-but not contralateral reaches by the experimenter. Thus, infants perseverated only following observation of actions they themselves were able to perform, suggesting that they coded others' actions in terms of motor simulation.

To study rate-based intersensory matching, infants first were familiarized with different auditoryvisual relations and then were tested for detection of auditory-visual equivalence. Across several different experiments, 4-, 6-, and 8-month-old infants first were habituated with (a) a single, temporally concordant auditory-visual compound stimulus, (b) a single, temporally discordant compound stimulus, (c) 2 different, temporally concordant compounds, or (d) a silently moving visual stimulus. A consistent and robust finding was a preference for the visual stimulus that moved at a novel velocity, indicating that the temporal attributes of the visual component dominated responsiveness. Only 1 experiment yielded evidence, albeit limited, of intersensory matching; infants habituated with a silently moving visual stimulus preferred the sound-specified visual stimulus in the presence of the rapid sound but not in the presence of the slow sound.

Little is known about how experiential factors guide and organize the development of intersensory perception. This study manipulated the amount of late prenatal and early postnatal experience with the temporal synchrony and spatial contiguity of audio-visual stimulation available to bobwhite quail embryos and hatchlings to explore this question. Results revealed that only embryos exposed to temporally synchronous and spatially contiguous audio-visual stimulation prior to hatching subsequently preferred spatially contiguous audio-visual maternal information following hatching, despite being denied postnatal visual experience. In contrast, embryos that did not receive exposure to both temporal synchrony and spatial contiguity (and were also denied postnatal visual experience) failed to show a preference for the spatial contiguity of maternal auditory and visual information following hatching. These results suggest that prenatal exposure to the amodal properties of temporal synchrony and spatial contiguity facilitate chicks' emerging sensitivity to the spatial contiguity of audio-visual information in the period following hatching. ß 2006 Wiley Periodicals, Inc. Dev Psychobiol 48: 233-242, 2006.