1. The document discusses recent research on how executive functions fit within the Cattell-Horn-Carroll (CHC) theory of cognitive abilities and their relationship to general intelligence (g). 2. Studies have found that white matter integrity, processing speed (Gt), and executive functions are strongly related to general fluid intelligence (Gf) and that processing speed may mediate the relationship between white matter integrity and intelligence. 3. The Parietal-Frontal Integration Theory (P-FIT) model proposes that the frontal and parietal lobes are important for constructs like working memory, attention, and executive functions that relate to general intelligence.

1. What about executive functions in CHC theory?
New research for discussion
Kevin S. McGrew, PhD
Institute for Applied Psychometrics
& University of Minnesota
© Institute for Applied Psychometrics, Dr. Kevin S. McGrew, 092116
(These are a small subset of slides that were part of a larger presentation made at the 2016 Australian
Psychological Society (APS) annual congress in Melbourne, Australia. Time did not allow for detailed
coverage of these slides—they are presented here “as is” for those who would like to view them)

2. Dr. Kevin McGrew, coauthor of the WJ IV, is
responsible for the content of this PPT module.
The information, hypotheses, and opinions expressed
in this PPT module do not necessarily represent the
opinions of the other WJ IV authors or HMH (the
publisher of the WJ IV)
© Institute for Applied Psychometrics; Kevin McGrew 05-04-16

3. http://tinyurl.com/z4swhlj
The next slide provides a framework for “connecting the dots” in intelligence
theory and testing-related research. A six-minute narrated animated video
explanation of this framework can be found at the link below. This framework is
important for understanding the last slide included in this module
© Institute for Applied Psychometrics, Dr. Kevin S. McGrew, 092116

4. Intelligence Testing
Related Research:
Levels of theoretical
reductionism and
explanation
White matter tract
organization, integrity
& efficiency
-rate of neural oscillations
-neural synchronization
-Reaction-time and temporal g
-ERP’s (e.g., ABR)
PMA1
T2 T3 T4 T5 T6 T7 T8 T9T1 T12T10 T11
PMA2 PMA3 PMA4 …etc
…etc
G1 G2 G3
…etc
g ?
(Consensus Cattell-Horn-Carroll Hierarchical Three-Stratum Model)
-Human Connectome
-Functional brain networks
(Bressler & Menon, 2010)
-“Rich club” network hubs
-P-FIT model
(Adapted from conceptual distinctions
of Earl Hunt, 2011)
© Institute for Applied Psychometrics, Dr. Kevin S. McGrew, 012314

5. What about executive functions and the CHC model?
A number of recent research
papers suggest interesting
hypotheses regarding the
nature of executive functions,
how they fit (or do not fit) in
the CHC taxonomy of human
cognitive abilities, and how they
may relate to the construct of
general intelligence (g). The
viewer is urged to read the
papers mentioned in this brief
module.
© Institute for Applied Psychometrics, Dr. Kevin S. McGrew, 092116

6. CHC-based CFA of 9
major data sets with
multiple different
cognitive and
neuropsychological
test indicators

11. © Institute for Applied Psychometrics, Dr. Kevin S. McGrew, 092116

14. Notice direction of arrows:
CHC abilities are considered to
be causal reflective variables
while g is considered to be a
formative variable that
“emerges”

15. “Executive processes act as a bottleneck”

16. Attention
Motor Power,
Speed & Timing
(Gp,Gps)
(feedback loop)
Central Executive
Working Memory Capacity (WMC)
= Efficiency of Attentional Control
(AC)
Gs=Attentional Fluency
Learning (storage)
efficiency (Glr)
Retrieval fluency
(Glr)
Focus of
Attention
Short-Term Working Memory (Gwm)
Sensory & Perceptual
Systems
Gf = Complexity of Reasoning
within Working Memory
(feedback loop)
Beyond CHC Theory
Adapted from Schneider & McGrew
(2012, 2013)
Visual (Gv)
Auditory (Ga)
Tactile (Gh)
Kinesthetic
(Gk)
Olfactory (Go)
Motor
Control
(Note: e.g.., Gv, Ga, etc. are
not simple visual perceptual or
sensory processing but the
complexity of visual processing
that a person can handle)
Gt = Speed of
Elem.Perc.
Processing
Cognitive Processing Speed (Gs)
Acquired Knowledge Systems (aka, long-term memory)
Etc.
(what)
Etc.
(how)
Etc.
(what)
Etc.
(how)
Motor
Sequences
(what)
Motor
Sequences
(how)
Grw
(what)
Grw
(how)
Gc
(what)
Gc
(how)
Nonverbal
(e.g., motor)
Cognitive
Environmental
Input
Includes both tacit and
explicit knowledge systems;
declarative (what) and procedural
(how) knowledge
Cognitive
performance
Motor
performance
© Institute for Applied
Psychometrics, Dr. Kevin
S. McGrew, 012314

17. Motor Power,
Speed & Timing
(Gp,Gps)
(feedback loop)
Learning (storage)
efficiency (Glr)
Retrieval fluency
(Glr)
Sensory & Perceptual
Systems
(feedback loop)
Beyond CHC Theory
Adapted from Schneider & McGrew
(2012, 2013)
Visual (Gv)
Auditory (Ga)
Tactile (Gh)
Kinesthetic
(Gk)
Olfactory (Go)
Motor
Control
(Note: e.g.., Gv, Ga, etc. are
not simple visual perceptual or
sensory processing but the
complexity of visual processing
that a person can handle)
Gt = Speed of
Elem.Perc.
Processing
Cognitive Processing Speed (Gs)
Acquired Knowledge Systems (aka, long-term memory)
Etc.
(what)
Etc.
(how)
Etc.
(what)
Etc.
(how)
Motor
Sequences
(what)
Motor
Sequences
(how)
Grw
(what)
Grw
(how)
Gc
(what)
Gc
(how)
Nonverbal
(e.g., motor)
Cognitive
Environmental
Input
Cognitive
performance
Motor
performance
© Institute for Applied
Psychometrics, Dr. Kevin
S. McGrew, 012314

18. The Parietal-Frontal Integration (P-FIT) Model of Intelligence
The frontal (esp., DLPFC) and
parietal lobes have been
repeatedly linked (via research)
to the cognitive constructs of
controlled attention, working
memory and executive
functions general intelligence
and higher level cognition

20. T
Focusing
attention
internally
Focusing
attention
externally
Short-term
storage
Response
selection
Working Memory
General
reasoning
Procedural &
Declarative
know.
Frontal Lobe
(DLPFC)
Parietal Lobe
Anterior
cingulate gyrus
The Brain and Working Memory: The Evidence-Based P-FIT Model
Adapted from Hunt
(2011)

23. Bivariate Cholesky decomposition for additive genetic (A), shared environmental (C), and
nonshared environmental (E) contributions to executive function (EF) and measures of intelligence

24. Multivariate Cholesky decomposition for additive genetic (A), shared environmental (C), and nonshared
environmental (E) contributions to executive function (EF), measures of intelligence, and speed

28. R2 = 58.6 % of Gf
variance explained
White matterGtGf

30. Indicators of g-factor were
WAIS-III Gs tests (Symbol
Search, Digit Symbol), Gsm
tests (Digit Span-Backwards;
Let-Num. Seq),
Gf test (Matrix Reasoning),
and Gv test (Block Design).
Indicators of g-speed were
measures of reaction time
(Gt) – simple reaction time,
four-choice reaction time,
inspection time)
CHC test classifications not by
article authors but by Kevin
McGrew as per CHC theory
Three biomarkers of white matter integrity

31. •White matter integrity markers strongly correlated.
• Individuals with lower (higher) integrity also tend to have lower (higher) integrity in
all other white matter tracts.
• Results found that g-speed (cognitive information processing speed) factor fully
mediated the effects of the integrity of all three white matter biomarker tracts
(g-speedg of -.81)
• White matter integrity is to a substantial degree a brain-wide property.
• If an otherwise healthy individual shows structural deficits in one track, all other
tracts will likely also be affected to some degree.
• “White matter tracts constitute the neuroanatomical infrastructure for any brain
network model of cognitive performance, and tract integrity can be directly linked to
cognitive information processing speed and via this mediating path to general
intelligence.” (p.4)

32. These two (and other studies) suggest interesting white matter, Gs/Gt, g/Gf relations
Gt
Gs
Gf
g
Approximately 60%
of variance
explained

33. Cognitive
performance
(reasoning,
comprehension,
etc)
The temporal resolution (faster
clock speed) of the brain
clock(s) results in greater neural
efficiency of the brain
Neural efficiency
influences brain network
communication efficiency
via white matter tracts,
particularly between the
parietal-frontal regions (P-
FIT neuro-model of
intelligence)
Frontal Lobe
(DLPFC) Parietal Lobe
White matter tracts
(brain network
communication infrastructure)
Network
communication
Knowledge in long-term
memory. Cognitive abilities.
Exec functions
focus
Working memoryImproves focus (attentional control
that maintains goal related
information active in working
memory) which in turn improves
efficiency of working memory, the
most central cognitive ability for new
learning and performance
Note: The origin
of this slide (which has
considerable animation)
was a 2012 keynote
presentation for
Interactive Metronome
(IM) and a MindHub Pub
(#3) that hypothesized
why IM may work. The
model is not IM-specific
and is relevant to the
information presented in
the current set of slides.
Visit
http://tinyurl.com/hwj86
z7 for access to the 2012
IM keynote video and
MindHub Pub
© Institute for Applied Psychometrics, Dr. Kevin S. McGrew, 092116