Reconceptualizing ADHD in the
classroom
Implications for Educators
Rosemary Tannock, PhD
The Hospital for Sick Children
Toronto, CANADA
Disclosures:
Novartis: Research funds
Lilly: Consultant, Research funds
Toronto, November 27th 2003
ADHD: Challenges for Educational
Systems
Education costs 3 to 6 times greater
(Forness et al., NIH Concensus, 2000)
– Prevalence (1 or 2 children in every class)
– Association with learning & social problems
Meaning for educational programming is
unclear
– What type of exceptionality/special needs?
– What are the Standards for level of service &
instruction?
– What are the required teacher qualifications?
Current paradox: ADHD
Clinical Perspective
Construct:
behavioral disorder
Diagnosis & Treatment:
behavioral symptoms
Neuroscientific Perspective
Construct:
neurobiological disorder
Diagnosis & treatment:
neurobiological &/or
neuropsychological features
Reconceptualizing ADHD for the classroom
Overview
Overlap with LD
Oral language, reading, arithmetic, written
expression in children with ADHD
Significance of inattention
Significance of working memory problems
Medical/Psychiatric: Learning Disorders
“…are characterized by academic
functioning that is substantially below that
expected given the person’s chronological
age, measured intelligence, and ageappropriate education.”
(DSM-IV-TR, APA, 2000)
Note: No requirement for evidence of
impairment in “basic psychological
processes
Legal/Educational:
Specific Learning Disability
“…a disorder in one or more of the basic
psychological processes1 involved in
understanding or in using language, spoken
or written, which may manifest itself in an
imperfect ability to listen, think, speak, write,
spell, or do mathematical calculations…”
(Individuals With Disabilities Education Act, June 4, 1997,
§602.26a. Emphasis added)
The “psychological process criteria” are not
specified. Also, most US states have operationalized
the phrase - “disorders of”- as a discrepancy between
ability (IQ) and achievement
1
Controversy in the Definition of LD
federal/legal/educational approach
– Discrepancy
– Heterogeneity
– Exclusion
Biobehavioral systems approach
–
–
–
–
Manifest disability
Cognitive/psychosocial traits
Environmental variables
Biological variables
Premise: IQ tests not necessary for the identification of LD
& do not contribute to intervention planning
Significant overlap between ADHD
& language/learning disorders
(Reviews: Cantwell & Baker, 1991; Tannock & Brown, 2000)
Epidemiological & clinical studies indicate that the rates of
overlap are greater than expected by chance between ADHD
&…
• language disorder: 8% - 30% (often unrecognized)
• reading disorder: 15% - 40%
• math disorder: 10% - 25% (often overlooked)
• disorder of written expression (common but unstudied)
• developmental coordination disorder: 10% - 50%
(rarely considered)
Early emergence of overlap of
ADHD & oral language problems
Gross-Tsur et al., 1991; Ornoy et al., 1993;
Szatmari et al., 1989; Tripp et al., 1999
Delayed onset of oral language:
– 6% - 30% ADHD group
1% - 6% of control group
Most preschoolers (80%) exhibiting
soft neurological signs &
language impairments & inattention/hyperactivity,
meet diagnostic criteria for ADHD & most
have learning disorders (RD) at school age
Longitudinal pathway of overlap between
ADHD & oral language problems
(McGee et al., JAACAP 1991)
Epidemiological prospective longitudinal study
of youngsters with “difficult to manage
behavior” plus language difficulties at age 3:
manifested as ADHD + reading disorders in
school-age
had worst outcome in terms of literacy and
psychopathology in adolescence, compared
to those with “difficult to manage behavior”
or language difficulties, alone.
The Canadian Scene:
Longitudinal course of overlap between
oral language & behavior problems
Preschool children in Ottawa with early
language delay & behaviour problems
(ADHD) show higher rates of
psychopathology in adolescence & young
adulthood (Beitchman et al, 1982, 1997)
Language Impairments in ADHD
often not recognized
High rate (58%) of undetected language
impairments in children referred for mental
health services in Ontario
Subtle but impairing language problems
may be obscured by more salient
behavioral symptoms
(Cohen et al., 1993, 1998a, 1998b)
Behavior problem or
communication problem in ADHD?
CONTEXT: PSYCHOEDUCATIONAL ASSESSMENT
Child: “What are we gonna do next? Huh? What’s in
there? What’s that?” (tries to grab test materials)
Adult: “You’ll see in a sec.”
(reaching into case for next set of test materials)
--- a few minutes later, child interrupts testing --Child: “Where’s the um…the things…um…where’s the
um… bugs?”
Adult: “Pardon? What bugs? There are no bugs here.
Now, look at this next page and-”
(child interrupts – whining then gets louder)
Child: “- The bugs. You said I’ll see the bugs. I don’t
wanna do this. I wanna see the bugs…
the um… secs… the insecs!”
Language Correlates of ADHD
several behaviour symptoms used in
ADHD diagnosis implicate memory and
language-related deficits
– fails to follow through on instructions
– does not appear to be listening
– blurts out answers, talks excessively
– forgetful of routines
What does the Research
Literature Show?
Studies of Expressive Language
word retrieval difficulties
poor conversational skills
weak message coherence
weak sentence formulation
language in elicited responses less
well-formed than spontaneous language
poor organization of narratives
Listening Comprehension is impaired in
ADHD even in the absence of comorbid
language impairments
McInnes, et al., J Abnormal Child Psychology (2003)
community sample of 77 boys
ADHD, ADHD+LI, LI, normal
main objective...
– listening comprehension for spoken
explanations (expository passages)
– facts and inferences
– ability to detect errors in explanations and
descriptions
– verbal and spatial working memory abilities
Main Findings
McInnes, et al., J Abnormal Child Psychology (2003)
ADHD group (normal basic language skills)
performed as well as peers in comprehending facts
but were
poorer at comprehending inferences - took longer
to explain their understanding
poorer at detecting errors in sequence of instructions
had significantly poorer verbal and spatial working
memory and poorer spatial memory span
Also, teacher ratings of inattention symptoms were
significantly related to comprehension of the passages
ADHD & Reading
Brock & Knapp, 1996; Cherkes-Julkowski et al., 1995;
Rucklidge & Tannock, 2002;
Decoding
– only if have concurrent phonologically-based reading
disabilities
Rate
– slow reading of single words & non-words, & of short
passages – despite good phonological abilities
Comprehension
– Weak reading comprehension for science texts
despite adequate decoding skills
– unclear whether problems attributable primarily to
slower reading rate
Dual-pathways to reading problems in
adolescence
McGee et al, JCPP 43(8) 2002
“ADHD”
Age 5-8
Hyperactivity
Ages 9 -11
Inattention
Ages 9 -11
Word Reading
Age 7-8
Inattention
Age 15
Word Reading
Age 15
Data from Australian Temperament Project & Dunedin
Multidisciplinary Health & Development Study
ADHD &
Arithmetic Computation
A neglected issue
Numeracy skills :
• predict employment and earnings
• related to health evaluation &
decision making
(e.g., Charette et al., 1998; Parsons & Bynner, 1997;
Rivera-Batiz, 1992; Woloshin et al., 2001;
International Adult Literacy Survey: Green & Riddell, 2001)
Arithmetic Computation Impairments
in ADHD Subtypes
Faraone et al., J Am Acad Child Adolesc Psychiatry 37:185-93, 1998
120
115
COMBINED(182)
110
HYP/IMP (28)
INATTENTIVE (92)
105
CONTROL (135)
100
95
a
90
a
a
85
80
WISC-FSIQ
WISC-3rd
Factor
WRATArithmetic
Computation
WRAT-Word
reading
aControls >
Inatt, Combined
ADHD & Mathematics
Computation
– Weak, even in absence of specific math
disability
– Multi-step computation appears particularly
problematic
Word problems
– Difficulty with irrelevant information
– Problematic even for youngsters with
sub-threshold inattention (sub-clinical ADHD)
Disruptive Talk or Private Speech & ADHD
CONTEXT D: ARITHMETIC IN LAB CLASSROOM
(Child with ADHD (9yrs old) seated alone at table with set of
math computation problems to be completed in 10-min)
Child: “Hmm. Two plus three… (counting on fingers)
that’s two, three, four, five!
(writes, erases, writes again)
Twenty-nine take away…. This is hard! (stands up)
Twenty-nine, twenty-eight, um… twenty-six.. uh-oh!
(erases vigorously, sharpens pencil, turns to next page)
Wow! Lots!(whispered. Turns back to previous page)).
OK. And three..nine, ten…ah!
Private speech, behavior & math
computation in ADHD
(Benedetto & Tannock, J Attention Disorders, 1999)
During a 10-min self-directed arithmetic
computation task, children with ADHD
– Use immature strategies (finger counting,
add-on)
– Use immature (externalizing) self-talk
– Exhibit low productivity
– Are more inattentive & fidgety
Compared to peers matched on age, IQ, &
math achievement,
ADHD & Written Expression
Anecdotally, the most common and impairing
problem at school.
Characterized by…….
–
–
–
–
–
Low productivity, poor fluency
Slow & effortful &/or fast & careless approach
Poor written spelling
Untidy, uneven, illegible handwriting
Poor written sentence construction
BUT….No systematic research to date
“The presence of even a few
inattentive behaviors in early
childhood should be viewed as a
developmental risk factor”
(Warner-Rogers et al., JLD,33:2000)
(Rabiner & Coie, JAACAP, 39:2000)
“The presence of even a few inattentive behaviors in
early childhood should be
viewed as a developmental risk factor”
(Warner-Rogers et al., J Learning Disabilities,33:2000)
(Rabiner & Coie, JAACAP, 39:2000)
Grade 1-2:
– “below average” academic skills
oral language, reading, written language, number concepts and
computation
– poor classroom adjustment
low confidence, need for repeated instructions
Kindergarten:
– poor reading achievement in Grade 5
Significance of Inattention
for cognitive processes
Chhabildas, Pennington, Willcutt, J Abnorm Child Psychol, 2001
Inattention symptom cluster is the
strongest predictor of neuropsychological
impairments
– vigilance, processing speed, inhibition
Hyperactivity/impulsivity not associated
with neuropsychological impairments
Working Memory
Helps the mind focus
“an attention
controller”
Working Memory
Multi-component cognitive system that allows us to
temporarily hold and manipulate information “on-line” for a
brief period (second).
Permits us to maintain information temporarily in a readily
accessible form while simultaneously processing new
information, often in the presence of distracting and
irrelevant information.
This continually updated internal “on-line” record of
relevant information guides decision making and overt
behavior (responses) during an activity, rather than
immediate sensory cues in the environment.
Plays a crucial role in a wide variety of complex cognitive
activities (e.g., mental arithmetic, reading comprehension)
Working Memory
(Baddeley, 1986; Fuster, 1995; Goldman-Rakic, 1996;
Miyake & Shah, 1999)
Multidimensional construct
– Processes:
On-line maintenance (span)
Manipulation (updating, shifting)
– Modality/representation:
Auditory/Verbal
Visual/Spatial
Working memory
(Brunel et al., 2001; Fuster, 2001; Gao, Krimer, Goldman-Rakic,
2001; Gutkin et al., 2001;
operates over periods of seconds
not localized in the brain, but rather comprises
transiently activated neural networks in
prefrontal cortex and other brain regions
– Persistent neuronal firing in the absence of a
stimulus
Influenced by chemical neurotransmitters
– Dopamine, noradrenaline
Working memory & attention
De Fockert, Rees, Frith, Lavie: Science, 291:1803-6, 2001;
Conway, Cowan, Bunting, 2001; Strayer & Johnston, 2001
Working
memory
• The greater the working memory load, the more the
individual will be distracted by irrelevant information.
• Implications: individuals with WM impairments will be
more readily overloaded & distractible
“Driven to Distraction”
(Strayer & Johnston, 2001)
Dual-task studies to assess effects of
cellular phone conversations on driving
performance
Driving performance impaired by
– Concurrent tasks that placed demand on
verbal working memory (e.g., in-depth
conversation) & diverted attention to those
activities
– Not by listening to radio or books-on-tape
Working memory & the cocktail party
phenomenon (Conway, Cowan, Bunting, 2001)
Humans exhibit the ability to attend to only
part of a noisy environment, yet highly
pertinent stimulus, can suddenly capture
attention
– In approx 33% individuals…
– Those with low working memory capacity
(span)
Working memory & language
acquisition (Baddeley, Gathercole & Papagno, 1998; Adams
& Gathercole, 2000; Willis & Gathercole, 2001)
Ability to maintain unfamiliar sound patterns (in
the “phonological loop”) while more permanent
memory records are constructed, plays a crucial
role in vocabulary acquisition
Children with limitations in working memory
exhibit narrower repertoire of words & syntactic
constructions, shorter utterances, & poorer
sentence repetition
Working Memory & Comprehension
Daneman & Merickle, 1996; Goel & Dolan, 2001; Haenggi,
Kintsch & Carpenter, 1995)
Ability to manipulate (& maintain)
information is essential for comprehension
visual-spatial working memory critical for
inferential comprehension
– neural substrates for visuo-spatial processing form
the basic representational building blocks used for
logical reasoning in 3-term relational arguments
A is in front of B; A is in front of C; thus, B is...
Hypotheses
Individuals with low working memory
ability (maintain/manipulate) will exhibit
– Greater distractibility, poorer sustained
attention
– Weaker oral language abilities
– Poorer inferential comprehension
Inattention, working memory, &
academic achievement
Community sample in the UK
Low working memory predicts
below-average performance on
national curriculum in language arts
and math, in 6 - 7 year-olds
(Gathercole & Pickering, 2000)
Potential Impact of WM Weaknesses
on Language Functioning
May forget what one was going to say
May get confused when given complex
instructions or explanations
Expressive language may not be cohesive or
coherent
– E.g., disorganized story-telling
Difficulty with turn-taking and topic shifts
Impact of Working Memory Deficits on
Academic Performance
Difficulty thinking through problems or engaging in
extensive reasoning in one’s head
Difficulty understanding meaning of a sentence while
decoding an unfamiliar word
Difficulty implementing necessary subskills in the
writing process while concurrently organizing and
writing text
Difficulty maintaining all relevant information in a
problem and monitoring progress
Working Memory is impaired in ADHD
(Martinussen & Tannock, under review)
Visual-spatial span & working memory
– associated with severity of inattentive
symptoms
(Barnett et al., 2001; Brito et al., 1999; Karatekin & Arsarnow, 1998;
Kempton et al., 1999; Mariani & Barkley, 1997; Martinussen et al.,
World Congress Psychiatric Genetics, 2002; Mealer et al., 1996;
Willliams et al., 2000
Verbal working memory
– inconsistent findings & may be associated
with comorbid language-based learning
disorders
Inattention, working memory, &
academic achievement
Low working memory predicts belowaverage performance on national curriculum
in language arts and math, in 6 - 7 year-olds
(Gathercole & Pickering, 2000)
It may be the combination of Inattention &
Working Memory that is problematic in
ADHD
Proposed relationship between working
memory, attention, language, & reading
Biological
factors
Environmental
factors
Neurobiological
Substrate
Working
Memory
Deficits
However… a cautionary note
To date, there is no cognitive
measure that can be used to rule in
or rule out ADHD
ADHD is a heterogeneous disorder
– Variation in symptoms
– Variation in co-existing disorders
BUT!
Working memory is a critical construct to
understand because:
– WM deficits are associated with learning
problems
– WM implicated in ADHD but not specific to
ADHD
– Seems to play a role in helping the mind focus
(de Fockert et al., 2001)
Clinical and Educational Implications
ADHD children (with normal basic language & decoding
skills) are likely to have problems in some aspects of
working memory & in higher level language
comprehension
could these problems account (in part) for….
some behaviour symptoms
reading comprehension difficulties
pragmatic/ social language problems
achievement problems in higher grades
Major points: ADHD
ADHD is a biologically-rooted neurocognitive
disability
ADHD is more usefully conceptualized as a type
of learning disability - rather than just a
behavioral problem
– It is frequently accompanied by one or more specific
LDs
Oral language, academic, & cognitive function
should be routinely assessed in ADHD
Major points:
Inattention & Working Memory
Inattention in K/G1 should be viewed as a
developmental risk factor
Most classrooms will have several students who
have one or more of the following difficulties:
– ADHD, reading,math, language comprehension,
anxiety, depression defiance,aggression
Many of these students are likely to have
problems with working memory, which impedes
learning
What are the treatment targets?
DSM-IV medical perspective
Brain
Abnormalities
Inattention
Hyperactivity
Impulsivity
Genetic
&
Environmental
Factors
Treatment
targets
?
Cognitive function, learning,
academic achievement
Emerging neuroscience/educational
perspective
Brain
Abnormalities
Genetic
&
Environmental
Factors
Treatment
targets
Specific
cognitive processes
Inattention,
Hyperactivity, impulsivity
Learning, Academic achievement
Implications for the Classroom
Target
Language, cognitive & academic
problems associated with ADHD
as well as
behavioral symptoms
Thank you
for your attention!
Questions