IQ Testing
&
Brain Damage
Full Scale IQ
Person’s relative standing in comparison w/ age-
related peers and global estimate of overall
mental abilities
Most Reliable and Valid Score
– BUT…it becomes less important as Verbal and
performance scores increase in difference and
subtest scatter increases
Verbal IQ
Verbal Comprehension Abilities:
-The ability to work with abstract symbols
-The amount and degree of benefit a
person has received from education
-Verbal memory abilities
-Verbal fluency
Performance IQ
Perceptual Organizational Abilities
– Degree and quality of nonverbal contact with
the environment
– Ability to integrate perceptual stimuli with
relevant motor responses
– Capacity to work in concrete situations
– Ability to work quickly
– Ability to evaluate visuo-spatial information
Book
In your book there is a description of each
subtest and exactly what it measures
starting on page 162. For example the
Vocabulary Test measures:
– Language Development
– Word Knowledge
– General Verbal Intelligence
– Etc.
V P differences
Must have a 9 pt. difference to interpret
Must interpret in context of age, education
and condition
Higher SES= higher verbal scores
Unskilled workers = higher performance
scores
If the above were switched it would
increase the interpretability of the scores
VP Differences
Do not interpret if
– Verbal comprehension and working
memory/freedom from distractibility are 10+
pts. Different
– If Perceptual Organization and Processing
speed are 13+ different
– If there is high subtest scatter
Index Scores
Only interpret index scores in the highest
and lowest scores are “not too different”
This point difference for each scale is on
page 149 of your book.
Verbal Comprehension Index
Perceptual Organization Index
Working Memory/Freedom from
Distractibility Index
Processing Speed Index
Verbal Comprehension Index
Extent to which a cl understands the
meaning of words
Can conceptualize verbal information
Extent of factual knowledge related to
verbal material
Ability to express material in words
THIS MATERIAL IS PRESENTED AS
ORAL QUESTIONS TO BE ANSWERED
Perceptual Organization Index
Extent of good nonverbal, fluid reasoning
Can integrate non-verbal material
Pays close attention to detail
Accurately responds to visual-spacial
material
Use of visual-spatial and visual motor
skills to solve problems
Working Memory/Freedom from
Distractibility
Related to concentration, attention, short-term memory
Lowered by poor number facility, anxiety, difficulty
making mental shifts and poor self monitoring
Requires motivation
The person must attend to stimulus and simultaneously
perform other mental tasks
Behavioral observations are crucial
– High asking for questions to be repeated (distractible)
– High motor activity, excessive talking (anxiety/mania)
– Must use with other measures to confirm (this is ONLY
supportive)
Processing Speed Index
Mental and Motor speed with which a
person can solve nonverbal problems
Person’s ability to plan, organize and
develop relevant strategies
Lowered by poor motivation
Assessing Brain Damage
Areas to Assess:
– Memory
– Learning
– Perceptual organization
– Problem solving
– Abstract reasoning
V>P
9 pts= Rt hemisphere lesion
15+ pts= impaired perceptual
organizational abilities
These support and do not diagnos
P>V
4 pts = lft hemisphere lesion
15+ pts = Language impairment
Don’t forget that SES, job, condition, age,
etc effect your interpretations
BOOK
Pages 181 & 182 talk about specific
subtest patterns and possible areas of the
brain that maybe damaged. This is a
comprehensive field of study and you
should consider this book a very minimal
introduction.
Other Uses for WISC Assessment
Alzheimers Disease- Initial Symptoms
include apathy, a decline in short-term
memory, and difficulties with problem
solving (Depression vs. Dementia)
Learning Disabilities
Giftedness
ADHD
Giftedness
V or P >= 130
Use WAIS-III, Stanford Binet, Samples of
work, achievement tests, rating forms,
designation by qualified professional.
IQ is only one prerequisite: Must need
internal motivation, discipline,
Environmental opportunities
Creativity is not measured by these tests
Learning Disabilities
Adequate Intelligence with a significant
difference in intellectual ability and achievement.
Must be an intrinsic disorder not due to MR,
brain damage, behavioral problems, sensory
handicaps or Environmental disadvantages
Purpose of Assessment: To identify strengths
and weaknesses; for appropriate placement in a
program
WAIS/WISC are “consistent with” not “diagnostic
of” LD/ADHD