1 Cognitive Development PSY 421 – Fall 2004

2 Overview Milestones of Development Studying cognition in infants and elderly adults Theorists in Cognitive Development Brain Development Perceptual Development Motor Development Attention Development Memory Development Other Cognitive Abilities Language Development Reading

3 Developmental Milestones Infants and Toddlers –Vision prior to 6 months = 20/600 at birth (very poor visual acuity), improves to almost 20/20 at 6 months –Hold up head = 3 months –Sitting up = 6 months –Babbling = 6 months –Roll over = 7 months –Crawling = 9 months –Walking = 12 months –Talking = 12 to 18 months –One-two word sentences = 18 months –Full sentences = 2 to 3 years

4 Developmental Milestones, continued Early Childhood –Begin to master skills like math, reading, and writing –Six- to 8-year-olds can rarely sit for longer than minutes for an activity. Attention span gets longer with age. –They can develop a plan to meet a goal. –Children begin to read and write early in middle childhood and should be skillful in reading and writing by the end of this stage.

5 Methodologies Used to Study Cognition Infants –Non-nutritive sucking on a pacifier –Kicking (Rovee-Collier and colleagues) –Imitation with props (Bauer and colleagues) –Habituation –Preferential looking Elderly Adults –Same research methods used for non-elderly adults –Interviews –Indirect or implicit tests of cognition

6 Theorists in Cognitive Development Piaget – stages of cognitive development; observed his own kids; methodologies not consistent across different kids; severely underestimated the abilities of children at particular ages; definitions of stages not supported Vygotsky – “the speech structures mastered by the child become the basic structures of his thinking.”; problem solving with the help of others (Zone of Proximal Development)

7 Brain Development Constantly changing between infancy and adulthood Neurons – almost all present before birth; number changes across lifespan; neurons die at different rates and in different parts of the brain Synaptic connections are made before birth and throughout life; connections are not permanent Plasticity in the brain

8 Perceptual Development Infants –Acuity is poor at birth –Saccades, focus, and fixations improve as the infant gets older –Contrast sensitivity in young infants is poor –Depth perception changes with age (looming, visual cliff studies, and heart-rate studies) –Perception of faces – high contrast is important Elderly adults –Acuity and contrast sensitivity start to decline –Nearsighted adults can become farsighted in their late years

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10 Motor Development Holding head up, sitting up, rolling over, and crawling are all very important for exploring the environment and important for cognitive development Reaching is also very important What is the earliest age that infants show controlled, coordinated movements? Motor development is very dynamic

11 Attention Development Infants and younger children have very short attention spans (average for a 5-year-old = 15 to 20 minutes) Selective attention is difficult for younger children – this changes the ease with which they can complete cognitive tasks compared to older children Young children tend to respond to things impulsively (Kogan, 1983) Young children tend to make fewer discriminations between similar objects than do older children (Gibson & Spelke, 1983) ADD/ADHD –4-5% of adults; 3-5% of children (approx. 2 million) –6 million prescriptions for stimulants to treat children (1995) –Data summarized by NIMH, leading source for ADHD research funding:

12 Memory Development Question: if infants appear to have poor memory abilities, what is this attributed to? Infantile amnesia = the inability of children-elderly adults to remember the first few years of their life (typically 4 years and prior) Memory span/capacity – improves with age but declines in elderly adults Speed of processing – faster with age until late in adolescence (then gets slower) Spontaneous memory strategy use (e.g.,) is difficult for young children and elderly adults Metamemory and metacognition Knowledge representation – dinosaurs (Chi & Koeske, 1983)

13 Other Cognitive Abilities Object Naming/Categorization –Begins to occur around 6 months (evidenced by pointing) –Colors, animals, everyday objects, letters, people, toys –Naming and categorization becomes more elaborate with speech Counting (3 years and up) –One to one principle = assign only one number to each object –Stable order principle = assign numbers in same order –Cardinality principle = last number assigned indicates that is the number in the set –Abstraction principle = the other principles apply to any set of objects –Order irrelevance principle = order in which objects are counted is irrelevant Problem-Solving –Infancy – imitation –Means-end analysis – 9 months and up –Board games – younger kids do not like to move backwards

14 Language Development - Infancy First word = 10 to 13 mos or longer Babbling starts 3 to 6 mos (due to biological maturation – deaf babies babble; motivation will not help) Dada, kitty, car, ball, milk, eye, hat, clock, bye Holophrases – one word utterances that contain an entire sentences worth of meaning Overextension = misuse words by extending one word’s meaning to include objects that are not related to the word’s meaning (dada pertains to all men) Underextension = failure to use a noun or name relevant to an event or object (doggie is their dog but no other dogs in the neighborhood)

15 Language Development - 18 to 24 months Two-word utterances are culturally similar Telegraphic speech = short, precise words to communicate (no articles or unnecessary words) Brown’s (1973) MLU (mean length of utterance) – indicator of language development based on number of morphemes per sentence that a child produces in a sample of about 50 to 100 sentences 5 stages: 1 (1+ to 2.0), 2 (2.5), 3 (3.0), 4 (3.5), 5 (4.0) Important because child who differ in chronological age by as much as.5 to.75 years still have similar speech patterns Better indicator of language development than chronological age

16 Language Development – Early Childhood Understanding is usually far ahead of word choice in speech Some sounds (r, s, sp) are still difficult Start to use endings, like –s and –ed, although they tend to overgeneralize (goed instead of went) Children can abstract grammar rules to novel situations Use wh- questions (especially WHY?) Use social language (please, thank you) Jokes – 3 years and up Learn 5 to 8 words a day from ages 1 to 6; after 5 or 6, it may be 22 new words a day

17 Reading Approaches –Basic skills and phonetics approach (Hooked on Phonics) = reading instruction should emphasize phonetics and basic rules for translating written symbols into sounds. Use simplified reading materials –Whole-language = reading instruction should parallel natural language learning; reading materials should be whole and meaningful I-P approach (Spear-Swerling & Sternberg) = combo of 2 approaches above –visual cue recognition (preschool, kindergarten) - use colors, symbols, signs to recognize words –phonetic cue recognition (kindergarten, first grade) – alphabetic insight (associating sounds to letters) –automatic word recognition (1st and 2nd grades) – sound out and recognize (after this stage, they can deal with meaning rather than just recognition) –strategic reading (middle-late elem. school years) –proficient adult reading (adolescence & adulthood)