Cognitive Performance & Theories of Intelligence

• Measuring cognitive performance, covering intelligence, achievement, and neuropsychological functioning, has been integral to clinical psychology since its beginning.
• Assessments of cognitive function aid in diagnosing and treating issues like learning disabilities and mood disorders.
• Intelligence tests are standardized assessments designed to measure a range of cognitive skills, including reasoning, problem-solving, comprehension, and memory. These evaluations help identify a client’s strengths and weaknesses in intellectual functioning.
• Achievement tests are specifically designed to evaluate the extent of an individual's knowledge, skills, and competencies in certain subject areas that they have learned over time. These assessments aim to quantify learning outcomes, indicating how well a person performs in academic subjects like mathematics, reading, and science, reflecting their educational experiences.
• Neuropsychological tests investigate brain dysfunction, including the impact of brain injuries and illnesses.

Classic Theories of Intelligence

• Contemporary intelligence tests originate from contrasting theories about intelligence.
• Clinical Psychologists have not reached a solid consensus on the definition of intelligence, which remains a complex and multifaceted concept. Various theories and models, such as Howard Gardner’s theory of multiple intelligences and Charles Spearman’s concept of general intelligence, illustrate the diverse perspectives within the field. This lack of agreement impacts assessments, treatment approaches, and the understanding of cognitive functioning in clinical practices.
• Aspects include: Processing speed, sensory capacity, abstract reasoning, imagination, adaptability, and learning ability.
• Singular vs Plural: the debate asks if intelligence is a single trait or many?
• Charles Spearman thought intelligence was a single factor, "g," representing overall intellectual ability.
• Louis Thurstone believed intelligence comprises multiple distinct abilities unrelated to each other.
• Thurstone pioneered multiple factor analysis to identify underlying factors in large datasets, finding independent factors like verbal comprehension and spatial reasoning.
• Spearman and Thurstone later agreed on a hierarchical model, acknowledging specific abilities ("s") related to a general intelligence ("g").
• James Cattell proposed fluid intelligence (reasoning with novel problems) and crystallized intelligence (accumulated knowledge)
• John Carroll's three-stratum theory includes a single "g", eight broad factors, and over 60 specific abilities.
• The Cattell-Horn-Carroll (CHC) theory combines the theories with 16 broad and 80 highly specific cognitive abilities
• Modern intelligence tests recognize both general and specific intelligences, providing an overall score and scores for particular abilities.

Common Intelligence Tests

• Wechsler and Stanford-Binet tests are frequently used to clinically assess patients.
• Other tests include the Woodcock-Johnson tests and the Kaufman Assessment Battery for Children II NU.
• The Woodcock-Johnson tests are available for early cognitive and academic development (ages 2.5-7) and cognitive abilities (ages 5-95).
• The Kaufman Assessment Battery for Children II NU is for ages 3-18

Wechsler Intelligence Tests

• Used since the early 1900s
• Highly regarded tests for clinical psychologists
• Three separate tests for different age ranges
• Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV)
  • For ages 16-90
• Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V)
  • For ages 6-16
• Wechsler Preschool and Primary Scale of Intelligence-Fourth Edition (WPPSI-IV)
  • For ages 2 years 6 months – 7 years 3 months
• These tests:
  • Yield a single full-scale intelligence score.
  • Yield 4 or 5 index scores.
  • Yield a dozen specific subtest scores.
  • They use a hierarchical intelligence model.
  • Administered face-to-face typically.
  • Requires interpersonal interaction and training
  • Brief subtests that last 2 -10 minutes.
  • Contain items with increasing difficulty
• Most subtests are present in all three tests as core or supplemental
• The tests include both verbal and nonverbal tasks
• WAIS has four factors, while WISC and WPPSI have 5.
  • Verbal Comprehension Index: verbal concept formation and reasoning
  • Perceptual Reasoning Index: fluid reasoning, spatial processing, and visual-motor integration
  • Working Memory Index: the capacity to store, transform, and recall incoming information
  • Processing Speed Index: the ability to process simple information rapidly and accurately
• Manuals for each Wechsler test include norms from about 2,000 people matching US Census data.
• Full-scale and index scores have a mean of 100 and a standard deviation of 15.
• Subtest scores have an average of 10 with a standard deviation of 3.
• Interpretation order: Full-scale IQ score, index scores, and then patterns of subtest scores.
• The tests are supported with empirical studies suggesting high reliability and validity.
• Used for intellectual disabilities, developmental delays, giftedness, educational/vocational planning, and school placement.
• Used to assess general intelligence in broader contexts such as Alzheimer's, mood disorders or ADHD
• The tests are available on a digital platform using the Q-interactive system.
• Strengths: reliability, validity, comprehensive data, wide age range, and clinical utility
• Limitations: culturally loaded subtests, ecological validity, and subjective scoring

Stanford-Binet Intelligence Scales - Fifth Edition (SB5)

• Administered face-to-face.
• Employs a hierarchical model of intelligence.
• Yields a single measure of full-scale IQ, five factor scores, and many more subtest scores.
• Has the same means and standard deviations as the Wechsler tests.
• Covers ages 2 - 85+ as a single test, unlike the Wechsler

SB5 Factors

• Fluid Reasoning: solves novel problems

• Knowledge: general information accumulated over time

• Quantitative Reasoning: solves numerical problems

• Visual-Spatial Processing: ability to analyze presented information

• Working Memory: ability to hold and transform information in short-term memory

• Each factor is measured verbally and nonverbally, with 10 areas each assessed by one to three item types

• The SB5 tests have made significant efforts to make more recent editions of their tests less culturally biased or loaded than earlier versions.

Universal Nonverbal Intelligence Test-2 (UNIT-2)

• A completely language-free test of intelligence.
• It requires no shared understanding of language or speaking.
• Administered one-on-one face-to-face.
• The examiner presents instructions via hand gestures.
• Responses consist of pointing or minor manipulation.
• Appropriate ages 5-21 years
• Normative data was collected from 1,800 people that match US Census data for age, sex, race etc.
• There are six subtests organized in tiers of memory and reasoning
  • Memory: object, spatial, and symbolic memory
  • Reasoning: cube design, mazes, and analogic reasoning
• UNIT-2 is praised for maximizing cultural fairness using language skill-free tasks.

Achievement Testing

• Achievement is what someone has accomplished intellectually, the kinds of subjects people learn in school.
• Achievement tests produce age/grade equivalency scores and standard scores.
• Achievement compared to intelligence was a key factor in determining learning disabilities.
• In DSM-5, "learning disability" changed to "specific learning disorder."
• Now diagnosis is based on person's achievement compared to the same level of people their age.
• Clinical psychologists explain their findings through written psychological reports.
• Types of tests: measure a single area of achievement or comprehensive tests with a range of subtests.
• Examples: Woodcock Johnson Tests of Achievement, the Kaufman Test of Educational Achievement, and the Wechsler Individual Achievement Test
• Each test is paired with an intelligence test and co-normed by the same company

Wechsler Individual Achievement Test (WIAT-4)

• Comprehensive achievement testing for ages 4-50
• Administered face-to-face or via telepsychology
• Measures achievement with 20 subtests available
• Scores on selected subtests are combined into composite scores, like language, reading, writing and math.
• Also yields a dyslexia index, and can serve as an initial screen for dyslexia
• The test has a very strong validity and is on the same scale as most intelligence tests: 100 is the mean as the standard deviation is 15.

Neuropsychological Testing

• It measures cognitive functioning or impairment of the brain and its structures
• Used for head injuries, prolonged alcohol/drug use, or degenerative brain illness.
• Helps plan rehabilitation, determine eligibility for accommodations, and establish baselines.
• Some tests are lengthy, with broad arrays of subtests, while others are briefer screens for impairment
• Evolved from fixed-battery to the flexible-battery phase.
• There is awareness of neuropsychological assessment anxiety.

Neuropsychological Batteries

• Halstead-Reitan Neuropsychological Battery (HRB)
  • A battery of eight standardized neuropsychological tests.
  • It is suitable for clients of age 15 years and above
  • Used to identify people with brain damage.
  • Some strengths are comprehensiveness and clinical usefulness.
• Luria-Nebraska Neuropsychological Battery (LNNB)
  • Relies more on qualitative written comments than the HRB does.
• NEPSY-II
  • Few batteries designed for children
  • Used for kids between 3 and 16 years of age
• Bender Visual-Motor Gestalt Test-Second Edition (Bender-Gestalt-II)
  • Is the most commonly used neuropsychological screen among clinical psychologists.
  • Measures visual constructive abilities.
  • Only takes 6 minutes to administer RBANS
  • Is a neuropsychological screen with visuomotor abilities. Tests verbal skills, attention, and visual memory.
• Wechsler Memory Scale
  • Used to assess individuals 16-90 with suspected memory issues.

Cultural Note

• Cultural competence is essential when selecting, administering, and interpreting neuropsychological tests.
• Caution against overpathologizing of diverse clients.
• It is important to consider culture-specific norms