4/29/20081Psy 427Cal State NorthridgeAndrew Ainsworth PhD Two years after the 1937 Binet revision, the first Wechsler test is published: the Wechsler-Bellevue Intelligence Scale. Criticisms of the 1937 Binet Intelligence is multifaceted, the Binet produces a single IQ score. The 1937 Binet was developed for children, yet purports to test adults. The 1937 Binet has an overemphasis on speeded/timed tasks, which is more difficult for older adults. Intelligence can decline as one ages. The 1937 Binet does not account for this.Cal State Northridge - Psy 427 2 Age Scale versus Point Scale 1937 Binet used an Age Scale Scores on a particular test are based on basal and ceiling levels. Each Basal or Ceiling Level had a chronological age associated with items at that level. So, a person who successfully completed 3 out of 4 items at the 6-year old level, would have a basal mental age of 6 years.Cal State Northridge - Psy 427 34/29/20082 1937 Binet used an Age Scale Content of items at each level of the age scale could vary tremendously Vocabulary word, arithmetic problem, and digit repetition, for example, could all be asked sequentially at a given age level of the 1937 Binet. 1939 Wechsler-Bellevue used a Point Scale Items in a scale answered correctly are each given a certain number of points. Point Scales allow for homogeneous content.Cal State Northridge - Psy 427 4 1939 Wechsler-Bellevue used a Point Scale Point Scales allow for homogeneous content. As such, Wechsler could obtain scores for an individual in a wide range of content areas. Vocabulary, Creative Thinking, Judgment, General KnowledgeCal State Northridge - Psy 427 5 1939 Wechsler-Bellevue included a Performance Scale 1937 Binet was criticized for its over-reliance on verbal skills to measure IQ 1939 Wechsler-Bellevue added a second entire scale of non-verbal measures.Cal State Northridge - Psy 427 64/29/20083 Normative sample for the 1939 Wechsler-Bellevue 1081 whites from the eastern US (primarily New York) First revision: 1955 Wechsler Adult Intelligence Scale (WAIS) Second revision: 1981 Wechsler Adult Intelligence Scale - Revised (WAIS-R) Third Revision: 1997 Wechsler Adult Intelligence Scale - 3rd Edition (WAIS-III) Standardization Sample based on 2450 adults in 13 age groups, stratified according to 1995 census data.Cal State Northridge - Psy 427 7 Other Test Versions Wechsler Intelligence Scale for Children (WISC; ages 6-16 yrs) The WISC was originally developed as a downward extension of the Wechsler Adult Intelligence Scale in 1949.  A revised edition (WISC-R) in 1974 as the WISC-R, and the third edition, the WISC-III in 1991.  The current version is the WISC-IV (2003)Cal State Northridge - Psy 427 8 Other Test Versions Wechsler Preschool and Primary Scale of Intelligence (WPPSI; 2.5 – 7.25 yrs)  Originally Developed in 1967 as a descendent of the WAIS and the WISC It has since been revised twice, in 1989 and 2002. The current revision, WPPSI–III provides subtest and composite scores that represent intellectual functioning in verbal and performance cognitive domains, as well as providing a composite score that represents a child’s general intellectual ability (i.e., Full Scale IQ).Cal State Northridge - Psy 427 94/29/20084 Other Test Versions Wechsler Abbreviated Scale of Intelligence (WASI) Was developed in 1997 along with the WAIS-III  A short, four-subtest version of the battery has recently been released, allowing clinicians to form a validated estimate of verbal, performance and full scale IQ in a shorter amount of time.  Uses vocabulary, similarities, block design and matrix reasoning subtests similar to those of the WAIS to provide an estimate of full scale IQ in about 30 minutesCal State Northridge - Psy 427 10Cal State Northridge - Psy 427 11SubtestsSkills TappedVocabularyword knowledgeSimilaritiesabstract, divergent thinkingArithmeticconcentration, working memoryDigit spanactive working memoryInformationfund of knowledgeComprehensionsocial/moral reasoning, judgmentLetter-number sequencing concentration, working memoryCal State Northridge - Psy 427 12SubtestsSkills TappedPicture Completionalertness to detailsDigit-Symbol (Coding)visual-motor skillsBlock Designnonverbal reasoningMatrix Reasoninginductive, NV reasoningPicture Arrangementplanning ability, social reasoningSymbol SearchSpeed of processingObject AssemblyPart-whole knowledge4/29/20085 Vocabulary Give a word, ask for a definition. Taps knowledge of words and their meanings. Good measure of “premorbid functioning” (intellectual capacity prior to trauma/illness) as brain “damage” continues, vocabulary is one of the last test scores to be affected. Very stable measure of intelligenceCal State Northridge - Psy 427 13 Similarities Present two words, ask how they are alike. Early items tap previously-learned associations. How are a dog and a cat alike? Later items require abstract thinking. How are liberty and freedom alike? Can also be used to find serious psychopathology Idiosyncratic reasoning.Cal State Northridge - Psy 427 14 Arithmetic Frequently thought to be a math test. Little math involved. More a test of active working memory If envelopes are 25¢ a dozen and you buy 3 dozen envelopes, how much change should you get back from a dollar? Subject to effects of anxiety, depression as well as cognitive deficits.Cal State Northridge - Psy 427 154/29/20086 Digit Span Numbers presented, one per second, to subject. Subject asked to repeat digits forward (part I) and reversed (part II). Separate scores are obtained for Digits Forward and Digits Reversed, but the scores generally combined for reporting. Taps active working memory, concentration, short-term auditory memory. Also subject to anxiety, depression, and other forms of psychopathology.Cal State Northridge - Psy 427 16 Information Ask a question about general knowledge, subject gives an answer. Taps general fund of knowledge, also curiosity, academic achievement, and the effects of an enriched environment. “How many senators come from each state in the United States?”Cal State Northridge - Psy 427 17 Comprehension Asks three different types of questions: Appropriate responses to hypothetical situations What is the thing to do if you