Cognitive Processes PSY 334

1. Cognitive ProcessesPSY 334 Chapter 13 – Individual Differences in Cognition August 28, 2003

2. Cognitive Development • Humans are born with immature brains. • Brain doubles in size during first year. • Brain size doubles again by puberty. • Much neural development takes place after birth. • Slow physical growth may provide a longer dependence on adults, giving time for the acquisition of knowledge.

3. Piaget’s Stages • Provides a structure for organizing observations of child behavior. • Currently being revised, corrected and restructured. • Controversy over idea that development progresses in stages rather than as a continuous process.

4. Studies of Conservation • Knowledge of what properties of the world are preserved under various transformations. • Object permanence – sensorimotor stage • Conservation of quantity, volume, weight changes at 6, the boundary between preoperational and concrete-operational.

5. What Develops • Two explanations for changes in children’s thinking: • They think better – more working memory. • They know better – more facts. • Probably both occur, due to neural changes: • Increase in synaptic connections. • Myelination increases neural transmission speed.

6. Memory Space Theory • Case – growing working memory capacity is key to developmental changes. • Some problems require more facts to be kept in memory. • Increased neural speed leads to increased memory capacity. • Practice reduces demands on working memory.

7. Examples • Noelting’s juice problems: • < 4 – all orange juice must be in one pitcher • 4-5 – pick pitcher with most orange juice • 7-8 – compare OJ with water • 9-10 – compute difference between OJ & water • Kail’s mental rotation problems – mental speed may increase due to practice.

8. Importance of Knowledge • Chi suggests developmental differences may be knowledge-related. • Kids do worse on memory tasks because they know less about the world. • Chess expert children do better at chess memory, worse on digit span. • Adults more familiar with digits, so do better. • Soccer memory study – only expertise mattered, not grade level.

9. Cognition and Aging • Decreases in IQ performance scores occur after age 20: • Related to speed of response on tests. • Older adults do better on jobs. • Age-related declines in brain function: • Cell loss, shrinkage & atrophy. • Compensatory growth of remaining cells. • Brain-related degenerative disorders such as Alzheimer’s.

10. Productivity in Old Age • With age, loss of neural function is steadily offset by growth of knowledge. • While the 30s may be the time of peak performance, very high performance frequently continues into 40s & 50s. • Speed of neural processing changes so less information can be held in working memory.

11. Psychometrics • Measures of performance of individuals on a number of tasks – examination of correlations across such tasks. • IQ Tests – Binet, Stanford-Binet, Wechsler • Mental age vs deviation IQ. • Factor analysis of performance scores: • Attempt to explain intercorrelations among subtests. • Ongoing debate about identifying factors.

12. Factor Theories • Spearman – one general factor called “g” • Multiple factors: • Thurstone – 3 (verbal, spatial, reasoning) • Guilford – 120 • Cattell’s theory: • Crystallized intelligence (acquired knowledge) – increases with age • Fluid intelligence – decreases with age. • Horn added spatial intelligence to fluid.

13. Carroll’s Three Strata • Lowest stratum – specific abilities (e.g., be a physicist), not inheritable. • Second stratum – broader abilities (verbal & spatial ability, reasoning, crystallized vs fluid). • Third stratum – correlations among second stratum abilities to form “g”

14. Kinds of Abilities • Reasoning ability: • Sternberg connects psychometrics to the information-processing approach. • People who score high on IQ tests also perform reasoning steps more quickly. • Verbal ability: • People who recall words more rapidly do better on verbal ability tests. • Working memory capacity is related to verbal ability.

15. Kinds of Abilities (Cont.) • Spatial ability: • Rate of mental rotation is slower for those with lower spatial ability test scores. • People with high spatial ability may choose to solve a problem spatially, not verbally. • Differences in abilities may result from differences in rates of processing and working-memory capacities. • Unclear whether this is innate or a difference in practice (nature vs nurture).

16. Gardner’s Multiple Intelligences • Gardner proposed that seven different intelligences are supported by different kinds of knowledge representation: • Separate neural mechanisms. • Separate developmental histories. • Cross-cultural universals in the display of such abilities. • Abilities: linguistic, musical, mathematical, spatial, bodily kinesthetic, personal (self-understanding, social).

17. Critique of Multiple Intelligences • Strong evidence for distinct linguistic and spatial intelligence. • Mathematical intelligence closely related to spatial so may not be distinct. • Remaining intelligences not usually considered cognitive but may be universal. • Gardner argues that intelligence is not unitary and thus hard to compare.