Perceptual Development

Can young children figure out a function of a novel object, then infer a different function? This practical flexibility increased from 3 to 5 years. Children solved problems by generalizing functions from a standard object, or by directly analyzing the choice objects. Three-year-olds incorrectly repeated (ie, perseverated) their first responses. Experiment 2 showed that children remember their first responses, so later inferences must overcome interference.

The main purpose of the present study was to investigate whether in natural environment, using very large physical distances, there is a trend to overconstancy for distance estimates during development. One hundred and twenty-nine children aged 5 to 13 years old and twenty-one adults (in a control group), participated as observers. The observer's task was to bisect egocentric distances, ranging from 1.0 to 296.0 m, presented in a large open field. The analyses focused on two parameters, constant errors and variable errors, such as measuring accuracy and precision, respectively. A third analysis focused on the developmental pattern of shifts in constancy as a function of age and range of distances. Constant error analysis showed that there are two relevant parameters for accuracy, age, and range of distances. For short distances, there are three developmental stages: 5-7 years, when children have unstable responses, 7-11, underconstancy, and 13 to adulthood, when accuracy is reac...

In this interview conducted by Agnes Szokolszky in 1997, Eleanor J. Gibson recounts her early research career and how her perspective changed from differentiation theory to an ecological theory of perceptual learning, under the influence of her husband, James J. Gibson. She recounts the several decade-long research work and social atmosphere at Cornell University, where together they created a lively scientific center of Ecological Psychology.  Eleanor Gibson gives a personal portrait of her husband and shares her observations on the reception of the Gibsonian approach in the scientific community in the 1980s and 1990s, and also on the development of Ecological Psychology as a movement. In her current reflection on the 1997 interview Karen Adolph, Eleanor Gibson's former graduate student at Emory University, commemorates her as a person and as a scientist and gives an imaginative representation of what Eleanor Gibson might think of the current state of psychology. The chapter contains a short biography and a list of Eleanor Gibson's ten most important publications.

Three experiments investigated the perception of substance and shape as invariant properties of objects by three-month-old infants. In experiment 1, infants were habituated to two differently shaped objects undergoing a rigid motion. After habituation of the infants, the objects were presented undergoing a different rigid motion, or undergoing a deforming motion, or undergoing the same rigid motion. Habituation was maintained to the new rigid motion, indicating that the two rigid motions were perceived as sharing an invariant property. Dishabituation, on the other hand, occurred when a deforming motion followed a rigid one. In experiment 2, infants were habituated to one shape undergoing two different rigid motions. After habituation, the shape was changed but the same two motions continued. Dishabituation occurred, compared to a group with no shape change, indicating that shape is distinguished as an invariant property over two rigid motions. In experiment 3, habituation to a shape...

A total of 60 children, 20 preschoolers, 20 first-graders, and 20 third-graders, participated in a game involving communication of spatial information. Subjects gave verbal directions to help another person find a hidden object, in this case, a small toy hidden under one of a number of cups. Two experimental conditions were set up, the first offering a relatively rich assortment of distinctive markings that could potentially be related to the array of cups, and the other not offering such distinctive markings. Generally, findings illustrate some aspects of developmental change. in children's use of spatial information and suggest that some unique task-related contextual effects exist in the communicative problem preseated to subjects. Major findings revealed that (1) the use of self-reference increased with age; (2) the use of listener as a reference point increased with age, and exceeded self-reference for the two youngest groups; (3) the third-grade children used a reference system near the hiding location more than a more remote reference system, whereas first-graders showed an opposite preference; and (4) the cup array itself was used often as a reference system by all subjects, regardless of their age or the availability of other differentiated environmental cues. (RH) *

Visual cues facilitate speech perception during face-to-face communication, particularly in noisy environments. These visual-driven enhancements arise from both automatic lipreading behaviors and attentional tuning to auditory-visual signals. However, in crowded settings, such as a cocktail party, how do we accurately bind the correct voice to the correct face, enabling the benefit of visual cues on speech perception processes? Previous research has emphasized that spatial and temporal alignment of the auditory-visual signals determines which voice is integrated with which speaking face. Here, we present a novel illusion demonstrating that when multiple faces and voices are presented in the presence of ambiguous temporal and spatial information as to which pairs of auditory-visual signals should be integrated, our perceptual system relies on identity information extracted from each signal to determine pairings. Data from three experiments demonstrate that expectations about an individual's voice (based on their identity) can change where individuals perceive that voice to arise from.

It is now widely accepted that the brunt of animal communication is conducted via several modalities, e.g. acoustic and visual, either simultaneously or sequentially. This is a laudable multimodal turn relative to traditional accounts of temporal aspects of animal communication which have focused on a single modality at a time. However, the fields that are currently contributing to the study of multimodal communication are highly varied, and still largely disconnected given their sole focus on a particular level of description or their particular concern with human or non-human animals. Here, we provide an integrative overview of converging findings that show how multimodal processes occurring at neural, bodily, as well as social interactional levels each contribute uniquely to the complex rhythms that characterize communication in human and non-human animals. Though we address findings for each of these levels independently, we conclude that the most important challenge in this fie...

During their first year, infants attune to the faces and language(s) that are frequent in their environment. The present study investigates the impact of language familiarity on how French‐learning 9‐ and 12‐month‐olds recognize own‐race faces. In Experiment 1, infants were familiarized with the talking face of a Caucasian bilingual German‐French speaker reciting a nursery rhyme in French (native condition) or in German (non‐native condition). In the test phase, infants’ face recognition was tested by presenting a picture of the speaker's face they were familiarized with, side by side with a novel face. At 9 and 12 months, neither infants in the native condition nor the ones in the non‐native condition clearly recognized the speaker's face. In Experiment 2, we familiarized infants with the still picture of the speaker's face, along with the auditory speech stream. This time, both 9‐ and 12‐month‐olds recognized the face of the speaker they had been familiarized with, but...

Introduction : The dynamic interaction between mother and infant is one of the indicative factors of infants’ social and emotional development especially in stressful situations as cognitive evaluating. Methods: An experimental study was completed in 2010 in Tehran on a total of 40 infants (18 boys and 22girls) forming two alternative groups and varying in age of infancy (4, 6, 8, 10 and 12 months). We used a 60 second mute popular “Tom & Jerry” animation to compare the infants’ attention in the presence or absence of mothers’ lap. Changes in orientation time, duration of sustained attention, and the total look duration were measured in terms of eye movement and heart rate changes through pulse oximeter. Furthermore, infants’ presence of general irritability in both conditions was observed. Results: We found that infants in their mothers’ laps showed more length of total look duration and sustained attention and less amount of general irritability than those sitting on baby seats. H...

Both objects and parts function as organizational entities in adult perception. Prior research has indicated that objects affect organization early in life: Infants grouped elements located within object boundaries and segregated them from those located on different objects. Here, we examined whether parts also induce grouping in infancy. Five-and 6.5month-olds were habituated to two-part objects containing element pairs. In a subsequent test, infants treated groupings of elements that crossed part boundaries as novel, in comparison with groupings that had shared a common part during habituation. In contrast, the same arrangement of elements failed to elicit evidence of grouping in control conditions in which the elements were not surrounded by closed part boundaries. Thus, infants grouped and segregated elements on the basis of part structure. Part-based processing is a key aspect of many theories of perception. The present research adds to this literature by indicating that parts function as organizational entities early in life.

Three-month-olds are sensitive to orientation changes of line drawings when they have a three-dimensional (3-D) interpretation and when the changes are deWned by both 3-D depth and two-dimensional (2-D) picture plane cues [Bhatt, R. S., & Bertin, E. (2001). Pictorial cues and three-dimensional information processing in early infancy. Journal of Experimental Child Psychology, 80, 315-332]. In the current study, we examined whether 3-month-olds are sensitive to pictorial line junction cues that signal orientation changes solely in the 3-D depth plane. The results revealed that infants discriminated a misoriented elongated cube in an array when the stimuli contained both shading and lines (Experiment 2) but not when only lines depicted the elongated cubes (Experiment 1). Testing with comparable 2-D images revealed that, even in the presence of shading information, detection of orientation changes is speciWc to images that have a 3-D interpretation. Together, the results suggest that 3-month-olds are sensitive to pictorial line junction cues that signal orientation changes in the 3-D depth plane to adults provided that shading information is available and the images have a 3-D interpretation.

Learning can be highly adaptive if associations learned in one context are generalized to novel contexts. We examined the development of such generalization in infancy in the context of grouping. In Experiment 1, 3-to 4-month-olds and 6-to 7-month-olds were habituated to shapes grouped via the organizational principle of common region and were tested with familiar and novel pairs as determined by the principle of proximity. Older infants generalized from common region to proximity, but younger infants did not. Younger infants failed to generalize when the task was easier (Experiment 2), and their failure was not due to inability to group via proximity (Experiment 3). However, in Experiment 4, even younger infants generalized grouping on the basis of connectedness to proximity. Thus, the ability to transfer learned associations of shapes to novel contexts is evident early in life, although it continues to undergo quantitative change during infancy. Moreover, the operation of this generalization mechanism may be induced by means of bootstrapping onto functional organizational principles, which is consistent with a developmental framework in which core processes scaffold learning.

Infants start tracking auditory‐only non‐adjacent dependencies (NAD) between 15 and 18 months of age. Given that audiovisual speech, normally available in a talker's mouth, is perceptually more salient than auditory speech and that it facilitates speech processing and language acquisition, we investigated whether 15‐month‐old infants' NAD learning is modulated by attention to a talker's mouth. Infants performed an audiovisual NAD learning task while we recorded their selective attention to the eyes, mouth, and face of an actress while she spoke an artificial language that followed an AXB structure (tis‐X‐bun; nal‐X‐gor) during familiarization. At test, the actress spoke the same language (grammatical trials; tis‐X‐bun; nal‐X‐gor) or a novel one that violated the AXB structure (ungrammatical trials; tis‐X‐gor; nal‐X‐bun). Overall, total duration of looking did not differ during the familiar and novel test trials but the time‐course of selective attention to the talker's face and mouth revealed that the novel trials maintained infants' attention to the face more than did the familiar trials. Crucially, attention to the mouth increased during the novel test trials while it did not change during the familiar test trials. These results indicate that the multisensory redundancy of audiovisual speech facilitates infants' discrimination of non‐adjacent dependencies.

Three experiments explored 5-and 7-month-old infants' intermodal coordination of proprioceptive information produced by leg movements, and visual movement information specifying these same motions. The visual information took the form of point light information for leg and feet movements, with visual displays presented in upright, ego-centered on-joint (Experiment 1, N ϭ 48); upright, ego-centered off-joint (Experiment 2, N ϭ 48); and inverted, observer-centered off-joint (Experiment 3, N ϭ 48) orientations. Measures of preferential looking indicated intermodal perception in infants of both ages while seeing on-joint, egocentered orientations, and for 7-month-olds (and possibly 5-month-olds) while seeing off-joint, ego-centered displays; neither age group demonstrated intermodal perception for off-joint, observer-centered displays. These results suggest that coordination of visual and proprioceptive inputs is constrained by infants' information processing of the displays, and have implications for infants' growing understanding of their self-movement and the development of knowledge of the self.

Social interactions often involve a cluttered multisensory scene consisting of multiple talking faces. We investigated whether audiovisual temporal synchrony can facilitate perceptual segregation of talking faces. Participants either saw four identical or four different talking faces producing temporally jittered versions of the same visible speech utterance and heard the audible version of the same speech utterance. The audible utterance was either synchronized with the visible utterance produced by one of the talking faces or not synchronized with any of them. Eye tracking indicated that participants exhibited a marked preference for the synchronized talking face, that they gazed more at the mouth than the eyes overall, that they gazed more at the eyes of an audiovisually synchronized than a desynchronized talking face, and that they gazed more at the mouth when all talking faces were audiovisually desynchronized. These findings demonstrate that audiovisual temporal synchrony plays a major role in perceptual segregation of multisensory clutter and that adults rely on differential scanning strategies of a talker's eyes and mouth to discover sources of multisensory coherence.

One critical skill to emerge over the first years of life is the ability to orient one's self spatially. Spatial orientation has often been tested using a modified Stage IV search task, in which children are encouraged to retrieve a toy hidden in one of two locations. Prior to searching for this toy, children experience either self-movement to a different position, or object-movement in which the toy is moved relative to the child's position. Results from these studies have found more accurate search following self-movement, relative to object movement. One key distinction between these situations is that selfmovement produces both visual and body movement information for spatial updating, whereas objectmovement produces visual information only. Thus, the superior search found after self-movement may result from the availability of multiple inputs for spatial updating. Unfortunately, no work has thoroughly explored the role of single versus multiple information sources on spatial orientation.

Tactile speech aids, though extensively studied in the 1980's and 1990's, never became a commercial success. A hypothesis to explain this failure might be that it is difficult to obtain true perceptual integration of a tactile signal with information from auditory speech: exploitation of tactile cues from a tactile aid might require cognitive effort and so prevent speech understanding at the high rates typical of everyday speech. To test this hypothesis, we attempted to create true perceptual integration of tactile with auditory information in what might be considered the simplest situation encountered by a hearing-impaired listener. We created an auditory continuum between the syllables /BA/ and /VA/, and trained participants to associate /BA/ to one tactile stimulus and /VA/ to another tactile stimulus. After training, we tested if auditory discrimination along the continuum between the two syllables could be biased by incongruent tactile stimulation. We found that such a bias occurred only when the tactile stimulus was above, but not when it was below its previously measured tactile discrimination threshold. Such a pattern is compatible with the idea that the effect is due to a cognitive or decisional strategy, rather than to truly perceptual integration. We therefore ran a further study (Experiment 2), where we created a tactile version of the McGurk effect. We extensively trained two Subjects over 6 days to associate four recorded auditory syllables with four corresponding apparent motion tactile patterns. In a subsequent test, we presented stimulation that was either congruent or incongruent with the learnt association, and asked Subjects to report the syllable they perceived. We found no analog to the McGurk effect, suggesting that the tactile stimulation was not being perceptually integrated with the auditory syllable. These findings strengthen our hypothesis according to which tactile aids failed because integration of tactile cues with auditory speech occurred at a cognitive or decisional level, rather than truly at a perceptual level.

This research investigated the early determinants of self‐other discrimination in infancy. Ninety‐six 4‐ and 9‐month‐old infants were placed facing a live image either of themselves or of another person (experimenter) mimicking them. The specular image was either contingent (on‐line), or contingent with a 2‐s delay. After a first 1‐min presentation, the video image of either the self or the other was suddenly frozen for 1 min (still‐face episode). This was followed by a last minute of live presentation. From 4 months of age, infants appeared to perceive and act differentially when facing the specular image of themselves or the mimicking other. In general, infants tended to smile more, look more, and have more protracted first‐look duration toward the mimicking other compared with the self. Developmentally, 9‐month‐olds showed markedly more social initiatives toward the mimicking other compared with the self during the still‐face episode. In all, these results indicate that infants d...

ILS conducted main statistical analyses, contributed to interpreting the results, wrote the first draft and edited subsequent versions of the manuscript. DLP contributed to the pre-processing of eye-tracking data and commented on earlier versions of the manuscript. ZL contributed to the interpretation of the results and editing the manuscript. MS conducted statistical analyses and contributed to the coordination of the study. AR conducted statistical analyses and contributed to the coordination of the study. CHANGES IN SELECTIVE ATTENTION TO THE MOUTH-Manuscript accepted in Infancy 2 AMK managed and conducted the data collection. PT conceived and designed the study, oversaw its execution, secured the funding, conducted main statistical analyses, contributed to the coordination of the study, the interpretation of the results and editing subsequent versions of the manuscript.

Developmental 1 Ecological Psychology began to conceptualize development in terms of the organism-environment system at a time when it was far from accepted to think about development in dynamic and systems terms. In this theoretical review, we argue that Developmental Ecological Psychology, based on mutualist ecological realism, has much to give to and to gain from other approaches to development that aim at building a developmental science on ecological-relational foundations. However, in order to exert greater influence, Developmental Ecological Psychology should pay attention to organismic development in a wider sense and should provide comprehensive theorizing about development as an ongoing and extended life process in multiple contexts. We review the theoretical foundations and prominent research directions in Developmental Ecological Psychology, noting strengths as well as lacunae. Then we move on to review major approaches that are partners for Developmental Ecological Psychology in a currently forming "coalition" of ecologicalrelational developmental science. In particular, we align the contributions of biologically rooted developmental systems approaches, dynamic systems approaches, phenomenologically rooted approaches, and sociocultural approaches. We focus on common ground, affinities, and synergies among these approaches and with Developmental Ecological Psychology. Thus, we define Developmental Ecological Psychology as an evolving, open discipline, seeking and finding principled cross-fertilization with a broad array of other relevant streams of thought. A developmental approach, in a systems setting-the organism-environment system-holds great promise and has the dignity of successful precedents in other sciences. (E. J. Gibson, 1994, p. 69) Developmental Ecological Psychology 2 is an evolving explanation of development rooted

Disciplines such as Alexander Technique or the Feldenkrais Method are examples of the numerous somatic movement practices to emerge during the early years of the Twentieth Century and which are widely employed in actor training. More recent practices that emanated from these early pioneers in somatic movement are less well known but are increasingly being applied to theatre. In this article I will introduce one of these practices, the somatic approach of Body-Mind Centering® and briefly locate its development in the lineage of somatic movement techniques. I will then offer two examples of specific somatic exercises that I employ in my work training actors, which are drawn from the principles of Body-Mind Centering. These are necessarily very concise segments of a large and comprehensive body of work, but will offer a window into the application of these techniques. Somatics and Somatic Movement are umbrella terms for various movement education and therapeutic approaches or techniques that work with the whole body. The term Somatic refers to the body, as distinct from some other entity like the mind, and comes from the Greek somatikòs which means "of the body". The term was put forward in 1976 by Thomas Hanna PhD. (1928-1990), a philosopher and practitioner of Feldenkrais" Functional Integration, who developed Hanna Somatic Education and published the Somatics Magazine-1 In the development of her work as a somatically based teacher and performer, Kate Kohler Amory trained under Dr. Martha Eddy in the Dynamic Embodiment-Somatic Movement Therapy and Education Training (DE-SMTT) which is a blend of BMC™ and Laban/Bartenieff. She also received an MFA from Naropa University where Somatic Movement is part of the training pedagogy taught by Wendell Beavers and Erika Berland. Under these master teachers she studied the principles of BMC and includes the DE-SMTT and BMC perspectives in her teaching. Amory has been inspired by the work of many teachers to whom she owes credit including, but not limited to:

Three recent publications, The Experience Machine, The Qualion Hypotheses and Somaesthetics and Design Culture, focus on prediction, consciousness and aesthetics, respectively. By understanding the interplay of these factors, designers can design for a better, more inclusive and effective future. The ideas proposed in these publications are consistent with the objectives of A Designer's Theory of Mind and its framework for purposeful design. To help readers unfamiliar with this theory or the subjects of these books, the updated theory is briefly introduced before the three publications are discussed.

Mental representation of absent objects and events is a major cognitive achievement. Research is presented that explores how toddlers (2-to 3-year-old children) search for hidden objects and understand out-of-sight events. Younger children fail to use visually obvious cues, such as a barrier that blocks a moving object's path. Spatiotemporal information provided by movement cues directly connected to the hidden object is more helpful. A key problem for toddlers appears to be difficulty in representing a spatial array involving events with multiple elements. Keywords object search; reasoning; cognitive development; toddlers Representation of absent objects is a hallmark of cognition because it frees the organism from reliance on simply what is in sight at the moment. Tasks requiring search for hidden objects have been used to explore cognitive development since Piaget made it a critical feature of testing infants' representation of out-of-sight objects (Piaget, 1954). While it is easy to replicate Piaget's finding that infants will not search for a desired toy that has disappeared under a cloth, it has been hard to interpret this puzzling behavior. In his chapter in the Handbook of Child Psychology (1983), Paul Harris proposed that the reason for infants' failure in the Piagetian search task is not that they lack object permanence, but rather they do not know where to search for the hidden object. Eventually the infant overcomes this problem and knows to lift the cloth to find the toy. Knowing where to search for a hidden object depends on one's ability to use the cues that indicate where the hidden object is. For the 10-month-old in Piaget's search task, the cue is the place of disappearance. The infant sees the toy disappear under a cover, so under the cover is the obvious place to look. For the toddler, more complex cues can be used. In our lab we have tested toddlers' understanding of motion cues of disappearance and reappearance from behind multiple hiding sites, and the contact mechanical cue of a barrier. The movement cues are appreciated at a younger age, but the barrier cue is not used until around 3 years of age. What are the constraints that prevent a child from using readily available cues? Why does a child have difficulty in applying relevant knowledge to solve a problem? We will review research from our lab and seek some resolution to these problems in this chapter. First, let us describe the task. The child is seated in front of an apparatus that features a ramp and an opaque screen that can be placed to hide a large section of the ramp. Four doors cut into the screen can be opened to reveal a hiding place, and a barrier can be placed perpendicular to the ramp behind any of these doors. The barrier protrudes above the screen by several centimeters and stands out because it is painted a different color from the screen and the ramp.

Several recent studies have revealed substantial limitations in 2-year-olds' ability to search accurately for objects that have undergone unseen movement, even along highly constrained paths. In many of these studies, children observed a ball as it rolled down a track and behind an occluding panel that contained 4 doors. The track had a barrier that was partly visible and could be placed in locations corresponding to the doors. When the ball came to a rest against the barrier and behind the occluder, the child's task was to find the ball by opening the correct door. The search accuracy of 2-year-olds has not differed from chance across several variations of this task. This research was conducted to identify the source of 2-year-olds' limitation in this domain. Children were granted a full view of the event before the ball was occluded with a door panel. Children's performance was better under this condition, but was still not systematically accurate unless their gaze remained locked onto the correct location. Two-year-olds' weak performance in these search tasks appears to be more a consequence of limitations in spatial integration than in their representation of unseen movement. The analysis of children's performance in search tasks has proven very effective in advancing our understanding of developmental changes in several domains (e.g.,

Toddlers show a surprising lack of knowledge about solidity when they are asked to search for a ball that rolled behind a screen and stopped at a barrier whose top was visible above the screen. They search incorrectly, failing to take into account the position of the barrier. This study examined details of this failure by simplifying the task in 2 ways: by using a search task that did not require children to understand solidity, and by using a prediction task that did not require children to conduct a search. For the prediction task, children had to predict where a ball was going to stop when a barrier intersected its trajectory. Children 2.0 and 2.5 years old were able to conduct a simple search and could predict, to some extent, where the ball was going to stop when the barrier was fully visible. Children did not show this predictive knowledge when the barrier was partially occluded by the screen.

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright

Lines in drawings can be perceived as the corners where surfaces intersect, outer boundaries of surfaces, or as markings on a surface. In this study infants' ability to distinguish between lines that indicate corners and edges and lines that indicate markings was investigated. Infants aged 7.5 months were habituated to line displays in which the lines specified a three-dimensional cube or two overlapping rectangles. Both displays contained lines indicating corners, edges, and surface markings. After habituation, infants viewed two test displays, one in which the corners or edges were deleted and one in which the surface markings were deleted. Infants looked significantly longer at the displays that lacked the corners or edges. The results suggest that infants attend to lines that depict corners and edges to a greater degree than they attend to lines that depict markings. Infants may do so because corners and edges specify the shapes of objects whereas markings do not.

Adults attend to a talker's mouth whenever confronted with challenging speech processing situations. We investigated whether L2 speakers also attend more to the mouth and whether their proficiency level modulates such attention. First, in Experiment 1, we presented native speakers of English and Spanish with videos of a talker speaking in their native and non-native language while measuring eye-gaze to the talker's face. As predicted, participants attended more to the talker's mouth in response to non-native than native speech. Then, Experiment 2 explored whether language proficiency affects attention to the talker's eyes and mouth when perceiving non-native, second-language speech. Results indicated that non-native speakers attended more to the mouth than native speakers, regardless of their level of L2 expertise. These results not only confirm that attention to a talker's mouth increases whenever speech-processing becomes more challenging, but crucially, they show that this is also true in highly competent L2 speakers.

The perceptual attunement to native vowel categories has been reported to occur at 6 months of age. However, some languages contrast vowels both in quality and in length, and whether and how the acquisition of spectral and duration-cued contrasts differs is uncertain. This study traced the development of infants' sensitivity to native (Czech) vowel-length and vowel-quality contrasts. The results suggest that in a vowel-length language, infants learn to categorize vowels in terms of length earlier and/or more robustly than in terms of quality, the representation of which may still be relatively underdeveloped at 10 months of age.

To study the development of responsiveness to binocular information, a display specifying an object approaching on a collision course was presented to 14-and 20-week-old infants. Responses to the stereoscopic collision display were compared to behavior evoked by a control display that lacked stereoscopic depth information. Videotape recordings were analyzed for evidence of convergence, avoidance behavior, and reaching. The head alignment of the 14-and 20-week-olds suggests that their eyes were converging on the stereoscopic display. However, only the 20week-old infants reached for the virtual object as it approached and reacted with defensive behavior at the time of collision, indicating sensitivity to binocular depth information.

Infants were tested in three experiments to study the development of sensitivity to information for impending collision and to investigate the hypothesis that postural changes of very young infants in response to an approaching object are of a tracking rather than of a defensive nature. Experiment 1 involved the presentation of three types of shadow projection displays, specifying (1) collision, (2) noncollision, and (3) a nonexpanding rising contour, to infants from 1 to 9 months of age. Avoidance of collision appears to be absent in 1-to 2-month-olds, begins to develop in 4-to 6-month-olds, and is present in 8-to 9-month•old infants. In Experiment 2, 1-to 2-month-old infants were presented with optical expansion patterns which specified collision and noncollision. The top contour of these displays stayed at eye level. No significant difference was observed between reaction to the collision and the noncollision displays, suggesting that the young infants were tracking the displays and not attempting to avoid collision. Experiment 3 was designed to determine whether an approaching real object might elicit an avoidance response in infants not sensitive to an optical display specifying collision. No evidence of avoidance behavior was observed in the 1-to 2-month-olds; however, avoidance, as indexed by blinking, does appear to be present at 4 months of age.

A moving cast shadow of the object affects the perception of the objectÕs trajectory in adults [Kersten, D., Mamassian, P., & Knill, D. C. (1997). Moving cast shadow induce apparent motion in depth. Perception, 26, 171-192]. In the present study, we investigated by using a habituation-dishabituation procedure whether infants at 4-to 7-months old discriminate the motion trajectory of a ball from the moving shadow it casts. In Experiment 1, 4-to 5-month-old and 6-to 7-month-old were tested for ability to discriminate between a ''depth'' display containing a ball and a cast shadow with a diagonal trajectory and an ''up'' display containing a ball with a diagonal trajectory and a cast shadow with a horizontal trajectory. Six-and 7-month-old, but not 4-and 5-month-old, infants looked significantly longer at the ''up'' display than at the ''depth'' display. In Experiment 2, we tested whether 4-to 5month-old and 6-to 7-month-old infants would perceive ''up'' motion as categorically different from ''depth'' depending on the objectÕs 3-D trajectory. We used displays containing a ball and a cast shadow with the same trajectories as those in Experiment 1 except that the cast shadows appeared above the ball. These displays did not produce 3-D impressions in adults. Neither age group of infants exhibited significant differences between ''up'' and ''depth'' displays. When the results from the two experiments are considered, 6-and 7-month-old infants discriminated the motion trajectory of the ball from the moving cast shadows. This developmental emergence of depth perception from a moving cast shadow at 6 months of age is consistent with that of other pictorial depth cues.

We were able to replicate the results of Pascalis et al. (2002). The ability to discriminate unfamiliar monkey faces is "narrowed" by 12-months of age. (using 20s fam. & 5s test) However, if familiarization and the time to visually compare the faces is doubled (40s familiarization & 10s test trials) 12month-olds show discrimination.

We tested whether dogs and 14–16-month-old infants are able to integrate intersensory information when presented with conspecific and heterospecific faces and vocalisations. The looking behaviour of dogs and infants was recorded with a non-invasive eye-tracking technique while they were concurrently presented with a dog and a female human portrait accompanied with acoustic stimuli of female human speech and a dog’s bark. Dogs showed evidence of both con- and heterospecific intermodal matching, while infants’ looking preferences indicated effective auditory–visual matching only when presented with the audio and visual stimuli of the non-conspecifics. The results of the present study provided further evidence that domestic dogs and human infants have similar socio-cognitive skills and highlighted the importance of comparative examinations on intermodal perception.

The present study examined 7-to 11-month-old infants' anticipatory and reactive reaching for temporarily occluded objects. Infants were presented with laterally approaching objects that moved at different velocities (10, 20, and 40 cm/s) in different occlusion situations (no-, 20 cm-, and 40 cm-occlusion), resulting in occlusion durations ranging between 0 and 4 s. Results show that except for object velocity and occlusion distance, occlusion duration was a critical constraint for infants' reaching behaviors. We found that the older infants reached more often, but that an increase in occlusion duration resulted in a decline in reaching frequency that was similar across age groups. Anticipatory reaching declined with increasing occlusion duration, but the adverse effects for longer occlusion durations diminished with age. It is concluded that with increasing age infants are able to retain and use information to guide reaching movements over longer periods of non-visibility, providing support for the graded representation hypothesis (Jonsson & von Hofsten, 2003) and the two-visual systems model (Milner & Goodale, 1995).

The two contrasting theoretical approaches to visual perception, the constructivist and the ecological, are briefly presented and illustrated through their analyses of space and size perception. Earlier calls for their reconciliation and unification are reviewed. Neurophysiological, neuropsychological, and psychophysical evidence for the existence of two quite distinct visual systems, the ventral and the dorsal, is presented. These two perceptual systems differ in their functions; the ventral system's central function is that of identification, while the dorsal system is mainly engaged in the visual control of motor behavior. The strong parallels between the ecological approach and the functioning of the dorsal system, and between the constructivist approach and the functioning of the ventral system are noted. It is also shown that the experimental paradigms used by the proponents of these two approaches match the functions of the respective visual systems. A dual-process approa...

Contrary to Block's assertion, ''identity-crowding'' does not provide an interesting instance of object-seeing without object-attention. The successful judgments and unusual phenomenology of identity-crowding are better explained by unconscious perception and non-perceptual phenomenology associated with cognitive states. In identity-crowding, as in other cases of crowding, subjects see jumbled textures and cannot individuate the items contributing to those textures in the absence of attention. Block presents an attenuated sense in which identity-crowded items are seen, but this is irrelevant to the debate about phenomenal experience of an object in the absence of object-attention. Finally, even unconscious object perception in identity-crowding likely involves an attention-like selective process.

The main purpose of the present study was to investigate whether in natural environment, using very large physical distances, there is a trend to overconstancy for distance estimates during development. One hundred and twenty-nine children aged 5 to 13 years old and twenty-one adults (in a control group), participated as observers. The observer's task was to bisect egocentric distances, ranging from 1.0 to 296.0 m, presented in a large open field. The analyses focused on two parameters, constant errors and variable errors, such as measuring accuracy and precision, respectively. A third analysis focused on the developmental pattern of shifts in constancy as a function of age and range of distances. Constant error analysis showed that there are two relevant parameters for accuracy, age, and range of distances. For short distances, there are three developmental stages: 5-7 years, when children have unstable responses, 7-11, underconstancy, and 13 to adulthood, when accuracy is reac...

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 North-Western 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; an...

The first time a newborn is held, he is attracted by the human's face. A talking face is even more captivating, as it is the first time he or she hears and sees another human talking. Older infants are relatively good at detecting the relationship between images and sounds when someone is addressing to them, but it is unclear whether this ability is dependent on experience or not. Using an intermodal matching procedure, we presented newborns with 2 silent point-line displays representing the same face uttering different sentences while they were hearing a vocal-only utterance that matched 1 of the 2 stimuli. Nearly all of the newborns looked longer at the matching point-line face than at the mismatching 1, with prior exposure to the stimuli (Experiment 1) or without (Experiment 2). These results are interpreted in terms of newborns' ability to extract common visual and auditory information of continuous speech events despite a short experience with talking faces. The implications are discussed in the light of the language processing and acquisition literature.

Abstract—Infants are able to adaptively associate auditory stimuli with visual stimuli even in their first year of life, as demonstrated by multimodal habituation studies. Different from language acquisition during later developmental stages, this adaptive learning in young infants is temporary and still very much stimulus-driven. Hence, temporal aspects of environmental and social factors figure crucially in the formation of pre-lexical multimodal associations. Study of these associations can offer important clues regarding how semantics are bootstrapped in real-world embodied infants. In this paper, we present a neuroanatomically-based embodied computational model of multimodal habituation to explore the temporal and social constraints on the learning observed in very young infants. In particular, the model is able to explain empirical results showing that auditory word stimuli must be presented synchronously with visual stimulus movement for the two to be associated. Index Terms—...

In this paper, we follow up on previous findings concerning first language (L1) perceptual attrition to examine the role of phoneme frequency in influencing variation across L1 contrasts. We hypothesized that maintenance of L1 Korean contrasts (i.e., resistance to attrition) in L1 Korean-L2 English bilinguals would be correlated with frequency, such that better-maintained contrasts would also be more frequent in the L1. To explore this hypothesis, we collected frequency data on three Korean contrasts (/n/-/l/, /t/-/t*/, /s/-/s*/) and compared these data to perceptual attrition data from a speeded sequence recall task testing the perception and phonological encoding of the target contrasts. Results only partially supported the hypothesis. On the one hand, /n/-/l/, the best-maintained contrast, was the most frequent contrast overall. On the other hand, /n/-/l/ also evinced the greatest frequency asymmetry between the two members of the contrast (meaning that it was the least important to perceive accurately); furthermore, /s/-/s*/, which was less well maintained than /t/-/t*/, was actually more frequent than /t/-/t*/. These results suggest that disparities in perceptual attrition across contrasts cannot be attributed entirely to frequency differences. We discuss the implications of the findings for future research examining frequency effects in L1 perceptual change.