Ch 5

childhood- "short, stubby fingers"

3 years Children can build surprisingly high block towers, each block placed with intense concentration but often not in a completely straight line Draw simple shapes, turn single page in books, independently use tools to eat 4 years Fine motor coordination is much more precise Write, cut with scissors along straight line and roughly around pictures, paste/glue, better able to manage clothing, trace

early childhood/preschool

3 years Hop, jump, and run back and forth, climb 4 years Climb stairs with alternate feet 5 years Run hard, ride bicycle, kick moving ball, skip rope

early childhood

5 years Tie shoes, fold paper, use scissors to cut out shapes, mastered most fasteners, cut soft food, coordinate hands to brush, independently write numerals

color vision

8 weeks infants can discriminate some colors 4 months, have color preferences. Saturated colors such as royal blue over pale blue Changes in vision reflect maturation Experience is also necessary for vision to develop normally

Sensory and Perceptual Development

A. What Are Sensation and Perception? Sensation Occurs when information interacts with sensory receptors—eyes, ears, tongue, nostrils, & skin (5 senses) The sensation of hearing -waves of pulsating air collected by the outer ear & transmitted through bones of the inner ear to auditory nerve. The sensation of vision -rays of light contact eyes, become focused on retina, & are transmitted by optic nerve to visual centers of brain

motor development

Arnold Gesell (1934) Developmentalist Through observations, thought he revealed how people develop motor skills Develop in fixed order, within specific time frames Motor development comes about through the unfolding of a genetic plan or maturation.

face perception

As infants develop, they change the way they gather information from the visual world, including human faces From 3 to 9 months of age, infants gradually began focusing their attention more on the faces of the characters in the animated film and less on salient background stimuli.

motor development

B. Reflexes - inborn reactions to stimuli Govern the newborn's movements, automatic & beyond newborn's control Genetically carried survival mechanisms Allow infants to respond adaptively to environment before they have had the opportunity to learn Survival

motor development

C. Gross Motor Skills - large-muscle activities; foundation is posture control The Development of Posture Dynamic process linked with sensory information in the skin, joints, and muscles tell us where we are in space; from vestibular organs in the inner ear that regulate balance & equilibrium; and from vision & hearing

visual perception

Childhood Perceptual development continues in childhood 3 to 4 years Children become increasingly efficient at detecting the boundaries between colors (such as red and orange) Childhood 4 or 5 years of age Most children's eye muscles are developed enough for them to move their eyes efficiently across a series of letters Many preschool children are farsighted, unable to see close up as well as they can see far away By the 1st grade, most children can focus their eyes and sustain their attention effectively on close-up objects

hearing

Cochlear implants—small, electronic devices that directly stimulate the auditory nerve—are now done routinely for children who are congenitally deaf, even as early as 12 months of age Many of the children with hearing-impairments, who have early cochlear implant surgery, show good progress in learning speech and in understanding others' speech, which allows them to function effectively in a hearing world Otitis media is a middle-ear infection that can impair hearing temporarily If it continues too long, it can interfere with language development & socialization As many as 1/3 of all children in U.S. have three or more episodes between birth and age 3 years Infection can develop into a more chronic condition in which the middle ear becomes filled with fluid, and this can seriously impair hearing. Treatments for otitis media include antibiotics and placement of a tube in the inner ear to drain fluid

the dynamic systems theory

Esther Thelen - dynamic systems theory Infants assemble motor skills for perceiving and acting Perception and action are coupled according to this theory To develop motor skills, infants must perceive something in the environment that motivates them to act and use their perceptions to fine-tune their movements Motor skills represent solutions to the infant's goals When infants are motivated to do something, they create a new motor behavior The new behavior is the result of many converging factors: The development of the nervous system The body's physical properties and its possibilities for movement The goal the child is motivated to reach The environmental support for the skill Mastering a motor skill requires the infant's active efforts to coordinate several components of the skill Infants explore and select possible solutions to the demands of a new task Infants assemble adaptive patterns by modifying their current movement patterns - "tune" movements Universal milestones, such as crawling, reaching, and walking, are learned through the process of adaptation: Infants modulate their movement patterns to fit a new task by exploring and selecting possible configurations Motor development is NOT a passive process in which genes dictate the unfolding of a sequence of skills over time. The infant actively puts together a skill to achieve a goal within the constraints set by the infant's body and environment Nature & nurture, the infant & environment, working together as part of an ever-changing system

Affordances

Experienced walker perceives slope affords possibility for faster locomotion & for falling

depth perception

Gibson and Walk (1960) explored whether infants might be able to perceive depth Constructed miniature cliff with a drop-off covered by glass "visual cliff" Placed infants on the edge of this visual cliff and had mothers coax them to crawl onto the glass - most would not crawl Most infants would not crawl out on the glass, choosing instead to remain on the shallow side, an indication that they could perceive depth, according to Gibson and Walk Critics point out that the visual cliff likely is a better test of social referencing and fear of heights than depth perception 6- to 12-month-olds had extensive visual experience 2- to 4-month-olds (don't crawl) difference in heart rates when placed on deep side These differences might mean that young infants respond to differences in some visual characteristics of the deep and shallow cliffs, with no actual knowledge of depth Although researchers do not know exactly how early in life infants can perceive depth, we do know that infants develop the ability to use binocular cues to discern depth by about 3 to 4 months

other senses

Hearing During the last 2 months of pregnancy, the fetus can hear sounds (mother's voice, music, etc.) Most developed sense at birth - hear at 33-34 weeks Hearing changes in infancy involve: Loudness: Infants cannot hear soft sounds quite as well as adults can; a stimulus must be louder to be heard by a newborn than by an adult

hearing- localization

Hearing changes in infancy involve Localization: Newborns can determine general location from where a sound is coming By 6 months, infants are more proficient at localizing sounds or detecting their origins Infants' ability to localize sounds continues to improve in the 2nd year

hearing- pitch

Hearing changes in infancy involve: Pitch: Infants are also less sensitive to low-pitch sounds Pitch is the perception of the frequency of a sound By 2 years, toddlers have considerably improved their ability to distinguish sounds with different pitches

visual perception

Infancy Visual Acuity Newborn perceives a world with some order which is far different from the one perceived by the toddler or adult At birth, the nerves, muscles & lens of the eye are still developing Newborns cannot see small things that are far away

infants

Infants refine ability to grasp objects, develop two grasps: Infants grip with the whole hand (palmer grasp) Infants grasp small objects with thumb & forefinger (pincer grip) Infant grasping system is very flexible Infants vary grip on objects depending on: size, shape, and texture, size of their own hands relative to the object's size Infants grip small objects with thumb & forefinger Grip large objects with all of the fingers of one hand or both hands Perceptual-motor coupling necessary for infant to coordinate grasp 4-month-old rely greatly on touch to determine how grip an object 8-month-old more likely to use vision as a guide Vision lets infants preshape their hands as they reach for an object Experience plays a role in reaching and grasping

infant face perception

Infants show an interest in human faces soon after birth 3 months: Infants match voices to faces, Distinguish between male and female faces, and Discriminate between faces of their own ethnic group and those of other ethnic groups

fine motor skills

Involve finely tuned movements, small muscle Grasp toy Use a spoon Button a shirt Anything that requires finger dexterity Also mouth (tongue, jaw, lips) Infants Hardly any control over fine motor skills at birth First 2 years of life, infants refine how they reach & grasp Initially, infants reach by moving shoulders & elbows crudely swinging toward an object Later, move wrists, rotate hands, & coordinate thumb and forefinger Newborn - strong reflexive grasp 2 mos. - wave arms at objects 3 mos. - touch objects but not grab and hold 4 mos. - grab but timing is off 6 mos. - grab & hold object 12 mos. - self-feed 24 mos. - grab is more selective

intermodal perception

Involves integrating information from 2 or more sensory modalities, such as vision and hearing Most perception is intermodal Early exploratory forms of intermodal perception exist in newborns (turn eyes & head to sound of rattle) These early forms of intermodal perception become sharpened with experience in the 1st year of life Babies are born into the world with some innate abilities to perceive relations among sensory modalities, but their intermodal abilities improve considerably through experience As with all aspects of development, in perceptual development, nature and nurture interact and cooperate

learning to walk

Locomotion & postural control closely linked, especially in walking upright To walk upright, must be able both to balance on one leg as the other is swung forward & to shift the weight from one leg to the other Learning to locomote, infants learn what kinds of places and surfaces are safe for locomotion Neural pathways for alternating legs - fetal period

development in the 2nd year

Motor accomplishments of 1st year bring increasing independence Infants explore environment more extensively & initiate interaction with others more readily (Non-mobile infants, Mobile infants) Toddlers become more motorically skilled & mobile Motor activity during the 2nd year vital to child's competent development Toddlers do NOT need exercise classes 13 - 18 months: Pull a toy attached to a string and use hands & legs to climb up a number of steps (down is more challenging) 18 - 24 months: Walk quickly or run stiffly for a short distance Balance on their feet in a squat position while playing with objects on the floor Walk backward without losing their balance Stand and kick a ball without falling Stand and throw a ball and jump in place

The Ecological View

Much of the research on perceptual development in infancy has been guided by the ecological view of Eleanor & James J. Gibson Argue that we do not have to take bits & pieces of data from sensations and build up representations of the world in our minds Instead, our perceptual system can select from the rich information that the environment itself provides We directly perceive information that exists in the world around us Perception brings us into contact with the environment in order to interact with & adapt to it Perception is designed for action In Gibson's view, all objects have affordances: Opportunities for interaction offered by objects that fit within our capabilities to perform activities.

Infant Visual Acuity

Newborn's vision estimated 20/240 on Snellen chart used for eye exams A newborn can see at 20 feet only as much as a normal adult can see at 240 feet By 6 months, on average, vision is 20/40

the development of posture

Newborns cannot voluntarily control their posture Within a few weeks, infants can hold their heads erect & soon lift their heads while prone About 2-3 mos., babies can sit while supported Around 6-7 mos., sit independently Typical age ranges for milestones About 8 mos., learn to pull themselves up & hold on About 10-12 mos. - stand alone

What Are Sensation and Perception?

Perception Interpretation of what is sensed Air waves that contact ears might be interpreted as noise OR as musical sounds Physical energy transmitted to retina of eye might be interpreted as particular color, pattern, or shape, depending on how it is perceived

perceptual-motor coupling

Perception and action are coupled—individuals perceive in order to move and move in order to perceive New perceptual-motor couplings do not occur as the result of genetic predetermination but rather because the infant actively assembles skills for perceiving and acting Perceptual and motor development do not occur in isolation from each other but instead are coupled

taste

Sensitivity to taste is present before birth Human newborns learn tastes prenatally through the amniotic fluid and in breast milk after birth At about 4 months, infants begin to prefer salty tastes, which as newborns they had found to be aversive

perceptual constancy

Sensory stimulation is changing, but perception of the physical world remains constant Allows the infant to perceive the world as stable 2 types of perceptual constancy: Size constancy Shape constancy Size Constancy The recognition that an object remains the same even though the retinal image of the object changes as you move toward or away from the object Begins 3 months - continues to develop 10-11 years Shape Constancy The recognition that an object remains the same shape even though its orientation to us changes Begins 3 months for regularly shaped objects

reflexes

The Rooting Reflex When stroke infant's cheek or touch side of the mouth Turn head toward the side touched in an apparent effort to find something to suck (disappears 3-4 months) The Sucking Reflex Newborns automatically suck objects placed in their mouth Get nourishment before associate nipple with food Later - sucking style Infants can change sucking rate & suck other things The Moro Reflex In response to sudden, intense noise or movement When startled, the newborn arches his back, throws back his head, flings out his arms and legs, then rapidly closes arms & legs Belief-way to grab for support while falling (disappears 3-4 mos.) It had survival value for our primate ancestors Keep some reflexes: cough, blink, yawn, sneeze, shiver Other reflexes disappear several months following birth as the brain matures and voluntary control over many behaviors develops The Grasping Reflex Something touches infant's palms, response grasp tightly 3 mos. - infant shows a more voluntary grasp, reflex diminish As her motor development becomes smoother, the infant will grasp objects, carefully manipulate them, and explore their qualities

nature, nurture, and perceptual development

There has been a long-standing interest in how strongly infants' perception is influenced by nature or nurture In the field of perceptual development, nature proponents are referred to as nativists Those who emphasize learning and experience are called empiricists. In the nativist view, the ability to perceive the world in a competent, organized way is inborn/innate The Gibsons' ecological view leans toward a nativist explanation of perceptual development because it holds that perception is direct and evolved over time to allow the detection of size & shape constancy, a 3-dimensional world, intermodal perception, and so on early in infancy However, the Gibsons' view is not entirely nativist because they emphasized that "perceptual development involves distinctive features that are detected at different ages" The Gibsons argued that a key question in infant perception is what information is available in the environment and how infants learn to generate, differentiate, and discriminate the information—certainly not a nativist view The Gibsons' ecological view is quite different from Piaget's constructivist view, which reflects an empiricist approach to explaining perceptual development According to Piaget, much of perceptual development in infancy must await the development of a sequence of cognitive stages for infants to construct more complex perceptual tasks In Piaget's view, the ability to perceive size and shape constancy, a three-dimensional world, intermodal perception, and so on develops later in infancy than the Gibsons' envision Today, an extreme empiricist position on perceptual development is unwarranted Much of early perception develops from innate (nature) foundations The basic foundation of many perceptual abilities can be detected in newborns As infants develop, environmental experiences (nurture) refine or calibrate many perceptual functions and may be the driving force behind some functions The accumulation of experience with and knowledge about their perceptual world contributes to infants' ability to form coherent perceptions of people and things A full portrait of perceptual development includes the influence of nature, nurture, and a developing sensitivity to information

ch 5 preview

Think about what is required for children to find their way around their environment, to play sports, or to create art. These activities require both active perception and precisely timed motor actions. Neither innate, automatic movements nor simple sensations are enough to let children do the things they do every day. How do children develop perceptual and motor abilities? In this chapter, we will focus first on the development of motor skills, then on sensory and perceptual development, and on the coupling of perceptual-motor skills.

the 1st Year: Motor Development Milestones & Variation

Timing of milestones may vary by as much as 2 to 4 months & experiences can modify onset (back to sleep & crawling) Some infants do not follow the standard sequence "Old-fashioned view - growth & motor development reflect merely age-related output of maturation is incomplete. Infants acquire new skills with help of caregivers in a real-world environment of objects, surfaces, and planes"

other senses

Touch and Pain Touch Newborns respond to touch Pain Newborns can feel pain - circumcision Smell Newborns can differentiate odors Prefer vanilla & strawberry to rotten eggs and fish

pattern perception

Young infants can perceive certain patterns. Prefer to look at a typical human face rather than one with scrambled features Prefer to look at a bull's-eye target or black-and white stripes rather than a plain circle