[W6] - CH15 Flashcards
An Introduction to Processing Speed
The ability to perform automatic cognitive tasks rapidly and accurately/ability to perform simple, repetitive
cognitive tasks quickly and fluently. It is a broad construct containing several specific abilities such as movement time, reaction time, correct and incorrect decision speed, perceptual speed, short-time retrieval speed, and retrieval fluency.
Tasks are usually timed on a fixed interval and require little in the way of
complex thinking, effort, or cognitive processing
An important predictor of skilled performance once people know how to do a
task
Must be considered when students have already learned a particular task or
skill and the difference in speed with which they perform that task or skill is
being measured
Processing speed deficits found in numerous clinical populations of children:
o With ADHD, Bipolar disorder, exposed prenatally to alcohol, reading disabilities etc.,
Schneider and McGrew’s Model of Processing Speed
Schneider and McGrew propose a reconceptualization of Glr (long-term retrieval) into two distinct abilities: GI (learning efficiency) and Gr (retrieval fluency).
GI refers to the ability to learn, store, and consolidate new information into memory, while Gr refers to the speed and accuracy with which information can be retrieved from memory.
The authors recommend combining certain tests to measure these abilities. They also propose a hierarchy of speeded abilities, including narrow abilities under Gs (broad cognitive speed) and Gr.
Miller’s Integrated SNP/CHC model incorporates these changes, and considers speed, fluency, and efficiency of processing as facilitators or inhibitors of cognitive and behavioral tasks.
The CHC Hierarchical Structure of Speeded Abilities
The CHC model of intelligence posits a hierarchy of speeded abilities with General Speediness in Stratum III, and four Stratum II broad factors: Psychomotor Speed, Decision Speed, Cognitive Speed, and Retrieval Fluency.
The degree of information processing needed, complexity of information, and characteristics of the stimulus differentiate these abilities.
The proposed hierarchy of speeded abilities encompasses changes in another CHC factor, Long-Term Storage and Retrieval.
The Neuroanatomy of Speed of Information Processing
[Still not fully understood] - The development of processing speed is dependent on the white and gray matter of the brain, with myelination (formation of the myelin sheath around a nerve fibre) of axons being a crucial factor in processing speed.
White matter tracts that are larger and better connected result in faster or more efficient processing. Greater gray matter volume is associated with faster
processing speed.
Females generally perform better on tasks of auditory and visual processing (denser and more well-connected white matter tracts - developed earlier than those of men)
Children with head injuries that caused axonal shearing (tearing of the myelin
sheath over the axons) or diffuse axonal injury (DAI) show deficits in
processing speed and reading fluency.
Age is also an important factor in understanding the relationship between neuroanatomical development and processing speed: processing speed improves drastically in early and middle childhood, slowing in late childhood and early adolescence, before reaching adult levels around ages 15–18, which corresponds to the myelination of the brain’s ventral and dorsal pathways!
Speed and Efficiency of Cognitive Processing Items From the
Neuropsychological Processing Concerns Checklist for Children
and Youth (NPCC-3)
Processing Speed and Fluency Difficulties:
* Takes longer to complete tasks than others the same age.
* Slow reading that makes comprehension difficult.
* Homework takes too long to complete.
* Requires extra time to complete tests.
* Responds slowly when asked questions.
Processing Speed and Accuracy Difficulties:
* Does not do well on timed tests.
* Difficulty recalling information accurately and quickly.
[Fluency deficits can manifest as slow speech or difficulties with reading, writing, and math. Retrieval deficits can make it hard to recall information from long-term memory. Although reading fluency is now recognized as a Specific Learning Disability (SLD) under the IDEA, processing speed deficits are not]
Integrated SNP/CHC Model Classifications of Speed
and Efficiency of Cognitive Processing
Broad:
Speed, Fluency
and Efficiency of
Processing Facilitators/
Inhibitors.
Second-Order: (5)
- Performance Fluency.
- Retrieval Fluency.
- Acquired Knowledge Fluency.
- Fluency and Accuracy.
- Qualitative Behaviors
Third-Order:
- Performance Fluency [Psychomotor Fluency; Perceptual; Figural; Naming; Oral Motor]
- Retrieval Fluency [Word Fluency; Semantic]
- Acquired Knowledge Fluency [Reading fluency: Rapid
phonological decoding; Reading fluency: Rapid
morphological decoding; Writing fluency; Mathematics fluency]
Performance Fluency and its Subclassifications
Fluency is the ability to quickly perform simple, repetitive tasks, no memory retrieval is required.
Psychomotor Fluency: Psychomotor fluency involves completing motor output tasks quickly and accurately. This ability is measured by psychomotor speed and movement time. Students with deficiencies in psychomotor speed and accuracy take longer to complete motor output assignments. The Visuomotor Precision test on the NEPSY-II is a solid measure of psychomotor fluency. Psychomotor fluency deficits can lead to difficulties in writing fluency and accurately copying information in a classroom.
Perceptual Fluency: The ability to quickly distinguish similar but different visual patterns and maintain attention under timed conditions.
Figural Fluency: Difficulty with figural fluency has been associated with right dorsolateral prefrontal circuit damage or dysfunction.
Naming Fluency: Rapid automatized naming (RAN). Naming fluency or RAN tests are frequently used for diagnosing reading disabilities in children. Naming fluency tests measure a student’s ability to process information quickly and accurately. Some tests only include completion time as a measure, while others include supplemental scores to analyze processing speed, accuracy, and self-correction errors. The D-KEFS Color-Word Interference Test and NEPSY-II Inhibition and Speeded Naming tests provide greater specificity for clinical interpretation, including self-correction errors.
Oral Fluency: A commonly used measure of oral motor fluency requires the student to repeat non-real words that follow phonological rules. Students with oral motor fluency deficits should be referred to a speech and language pathologist (SLP) for further evaluation. The NEPSY-II Oromotor Sequences test provides process scores that aid in clinical interpretation. (referral to SLT?)
Retrieval Fluency and its Subclassifications
Retrieval fluency tasks require recalling words quickly, either starting with a certain letter or within a semantic category.
These tasks combine speed of retrieval and memory recall, but do not measure memory storage.
Difficulty with verbal retrieval fluency is associated with left dorsolateral prefrontal circuit damage, and difficulty with nonverbal retrieval fluency is associated with right dorsolateral prefrontal circuit damage.
Students with retrieval fluency deficits may have difficulties with finding the right words to say.
Acquired Knowledge Fluency and its Subclassifications
Acquired knowledge fluency measures the automaticity of processing for rapid reading, writing, and solving math problems. Good fluency in these areas facilitates comprehension, while poor fluency inhibits comprehension.
Reading Fluency: Reading fluency was added as a type of Specific Learning Disability (SLD) with the revision of IDEA in 2004. Many academic test publishers have developed reading fluency measures, and the PAL-II RW is recommended for a thorough assessment of reading fluency. Poor reading fluency is typically associated with poor decoding skills, which slows down the automaticity of reading and adversely affects reading comprehension. The PAL-II RW includes measures of both rapid phonological and morphological decoding as well as silent reading fluency.
Writing Fluency: Writing fluency is not yet recognized as a specific learning disability (SLD) in IDEA, but it is an important skill to be assessed. Writing fluency represents the automaticity of writing and can be adversely affected by deficiencies such as poor graphomotor output or poor language abilities.
Mathematics Fluency: Mathematics fluency refers to the automaticity of solving math problems quickly and efficiently. Although it is not yet recognized as a specific learning disability in IDEA, it is important to be assessed. The foundation of mathematics fluency is the rapid and accurate retrieval of math facts. There are various reasons why mathematics fluency can be disrupted, and different tests are available to measure mathematics fluency.
