Invitation to the Life Span by Kathleen Stassen Berger Chapter 3- The First Two Years Body and Brain PowerPoint Slides developed by Martin Wolfger and Michael James Ivy Tech Community College-Bloomington Body Changes Height and Weight • Average weight at birth: 7.5 pounds • Average length: 20 inches • These numbers are norms, an average measurement. Body Changes Body Changes Brain Development • Neuron- nerve cell. Billions in the central nervous system. • Cortex- the outer layers of the brain. • Axon- a fiber that extends from a neuron and transmits electrochemical impulses from that neuron to the dendrites of other neurons. Body Changes • Dendrite- a fiber that extends from a neuron and receives electrochemical impulses transmitted from other neurons via their axons. • Synapse- the intersection between the axon of one neuron and the dendrites of other neurons. • Neurotransmitter- a brain chemical that carries information from the axon of a sending neuron to the dendrites of a receiving neuron. Body Changes • Newborns sleep about 17 hours a day, in one- to three-hour segments. • Newborns’ sleep is primarily active sleep: often dozing, able to awaken if someone rouses them, but also able to go back to sleep quickly if they wake up, cry, and are comforted. • Quiet sleep: slow brain waves and slow breathing • Newborns have a high proportion of REM (rapid eye movement) sleep, with flickering eyes and rapid brain waves. Moving and Perceiving Motor Skills • The first movements are not skills but reflexes, involuntary responses to a particular stimulus. Moving and Perceiving Some reflexes help insure survival: breathing, thrashing, shivering, sucking, rooting, swallowing, spitting up. • • • • • Other reflexes are signs of normal functioning: Babinski reflex. When infants’ feet are stroked, their toes fan upward. Stepping reflex. When infants are held upright with their feet touching a flat surface, they move their legs as if to walk. Swimming reflex. When they are laid horizontally on their stomachs, infants stretch out their arms and legs. Palmar grasping reflex. When something touches infants’ palms, they grip it tightly. Moro reflex. When someone startles them, perhaps by banging on the table they are lying on, infants fling their arms outward and then bring them together on their chests, as if to hold on to something, while crying with wide-open eyes. Moving and Perceiving • Gross motor skills- Physical abilities involving large body movements, such as walking and jumping. • Fine motor skills- Physical abilities involving small body movements, especially of the hands and fingers, such as drawing and picking up a coin. Moving and Perceiving Moving and Perceiving Sensation and Perception • Sensation- The response of a sensory system (eyes, ears, skin, tongue, nose) when it detects a stimulus. • Perception- The mental processing of sensory information when the brain interprets a sensation. • Sensory development- typically precedes intellectual and motor development. Moving and Perceiving The sense of hearing develops during the last trimester of pregnancy and is already quite acute at birth; it is the most advanced of the newborn’s senses. Vision is the least mature sense at birth. – Newborns focus only on objects between 4 and 30 inches away. – Binocular vision, the ability to coordinate the two eyes to see one image, appears at 3 months. – Sensation is essential for the visual cortex to develop normally. Surviving in Good Health Preventing Sudden Infant Death Syndrome • In 1990, about 5,000 babies died of sudden infant death syndrome (SIDS) in the United States. • The actual cause of SIDS is still unknown: low birthweight, heavy clothing, soft bedding, teenage parenthood, and, particularly, maternal smoking are risk factors. • Putting infants to sleep on their backs reduces the risk but does not eliminate it. Surviving in Good Health Adequate Nutrition • For every infant disease (including SIDS), breast-feeding reduces risk and malnutrition increases it, stunting growth of body and brain. • Breastfed babies are less likely to develop allergies, asthma, obesity, and heart disease. • As the infant gets older, the composition of breast milk adjusts to the baby’s changing nutritional needs. Infant Cognition Piaget • sensorimotor intelligence – Piaget’s term for the way infants think—by using their senses and motor skills—during the first period of cognitive development. • assimilation – Piaget’s term for a type of adaptation in which new experiences are interpreted to fit into, or assimilate with, old ideas. • accommodation – Piaget’s term for a type of adaptation in which old ideas are restructured to include, or accommodate, new experiences. • object permanence – The realization that objects (including people) still exist when they can no longer be seen, touched, or hear. Infant Cognition Infant Cognition • The visual cliff was designed to provide the illusion of a sudden dropoff between one horizontal surface and another. • Mothers were able to urge their 6-montholds to wiggle forward over the supposed edge of the cliff, but 10-month-olds fearfully refused to budge. Infant Cognition Early Memory • According to classic developmental theory, infants store no memories in their first year. • Developmentalists now agree that very young infants can remember if the following conditions are met: – Experimental conditions are similar to real life. – Motivation is high. – Special measures aid memory retrieval. Language Learning Early Communication • Child-directed speech- The high-pitched, simplified, and repetitive way adults speak to infants. (Also called baby talk or motherese.) • Babbling- The extended repetition of certain syllables, such as ba-ba-ba, that begins when babies are between 6 and 9 months old. • Naming explosion- A sudden increase in an infant’s vocabulary, especially in the number of nouns, that begins at about 18 months of age. Language Learning First Words • At about 1 year, babies speak a few words. • Spoken vocabulary increases gradually (about one or two new words a week). • Once spoken vocabulary reaches about 50 words, it builds quickly, at a rate of 50 to 100 words per month. Language Learning Cultural Differences in Language Use • Holophrase- A single word that is used to express a complete, meaningful thought. – All new talkers say names and utter holophrases. • Infants differ in their use of various parts of speech, depending on the language they are learning, e.g. more nouns and fewer verbs. Language Learning Acquiring Grammar • Grammar includes all the devices by which words communicate meaning: sequence, prefixes, suffixes, intonation, loudness, verb forms, pronouns, negations, prepositions, and articles. • Worldwide, people who are not yet 2 years old already use language well. Language Learning • • • • • Hypotheses About Language Development Learning Approach Infants need to be taught B. F. Skinner (1957) noticed that spontaneous babbling is usually reinforced. Parents are expert teachers, and other caregivers help them teach children to speak. Frequent repetition of words is instructive, especially when the words are linked to the pleasures of daily life. Well-taught infants become well-spoken children. Language Learning Language Learning is Innate • Language acquisition device (LAD)Chomsky’s term for a hypothesized mental structure that enables humans to learn language, including the basic aspects of grammar, vocabulary, and intonation. Language Learning Social Impulse Toward Communication • Infants communicate in every way they can because humans are social beings, dependent on one another for survival, well-being, and joy.