Lecture #9: intelligence testing

Singular model (spearman)

Intelligence is singular and relfects a singel ability (“G”=general)

Plural model (Thurstone)

Intelligence is a range of abilities, many types dont correlate

Hierarcheal model

Model currently used, blends G-factor with specifc factors

IQ test uses

• Future academic prediction (freshmen year of college)

• influence therapy approach

• characterizes function impairment

• track cognative changes

Intelligence (Weschler definition)

the capacity of a person to act, think, and deal rationally and effectively

Full score IQ

Part of WAIS, total performance (“Intelligence quotient”)

General Index ability (GSA)

Based on VCS and PRS, estimate of intelligence without motor skills

Verbal Comprehension Index (VCI)

Verbal conception formation and reasoning

• similarities

• vocab

• general info

• comprehension

Visual Spatial Index (VSI)

Spatial processing and visual motor integration

• Block design puzzle

• visual puzzles

Fluid reasoning index (FRI)

Deductive reasoning and logical thinking

• figure wieights

Working Memory Index (WMI)

Capacity to store, transform, and recall info in a short term memory

• Running digits

  • “say the last #s in a sequence”

• Digit sequencing

  • “Say #s in order from smallest to largest”

Processing Speed Index (PSI)

Ability to rapidly and accuratly process simple info

• coding (#s and shapes)

• symbol search

WAIS scoring

• Norm referenced assessment

• Average IQ for age is 100

  • ranges based on cutoffs

Norm-referenced assessment

scoring is relative to other peers in sample group of the same age

Normative sampling

Group used to establish the baseline

Psychometrics

• increased standardization

  • same questions, intensive clinician training

• Increased reliability for FSIQ and subscores

Genetic/environmental factors

• Heritability .4-.8

  • Lower in low SEC families

• Intelligence polygenetic

• Lower micronutrients, environmental toxins= lower IQ

• SEC variables

• Breast-feeding=increased IQ

• Education intervention in low SEC= increased IQ