Article for Category: ‘ADHD’

If you want to sell it, put a brain on it

December 19th, 2012

It feels like 90% of the products being hawked as treatments for learning and developmental disorders like dyslexia, language impairments, autism, Asperger’s and ADHD make claims about the brain. Claims include:

  • “based on brain science”.
  • “designed by neuroscientists”
  • “brain based”
  • “neuroplasticity”
  • “sharpen memory and attention with brain games and tools”
  • “change your brain”.

There’s a good reason why companies invoke brain science in selling products. Research has shown that consumers are more likely to rate a claim as credible if it is accompanied by a picture of a brain image (McCabe & Castel, 2008). This seems to happen even if the claim is complete nonsense. Is it any wonder that programs and products (see here, here and here for examples) invoke the brain in the marketing process? It seems human lose their powers of reasoning when presented with a brain.

The neuroscientist Molly Crockett has given a recent TED talk titled “Beware neuro-bunk” in which she cautions against placing too much stock in claims ‘based on neuroscience’.

Crockett cautions us that there’s always more to the story than the brain images. She says “if someone tries to sell you something with a brain on it, ask to see the evidence. Ask for the part of the story that’s not being told.”

Here are other cautionary tales on the same subject:

Psychology Today

The New Statesman

The New Yorker

Journal of Cognitive Neuroscience

The Conversation (Max Coltheart)

The Conversation (Anne Castles & Genevieve McArthur)

Dorothy Bishop

Happy holidays.

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Causes of ADHD

October 01st, 2012

ADHD is a controversial disorder despite being recognised as a valid clinical entity for many decades. A recent study (Thapar et al., 2012) has examined the evidence on the causes of ADHD in a review in the Journal of Child Psychology & Psychiatry. The paper is open to all, not just subscribers if you want to read it. At the time of this post it was available in the Early View part of the JCPP homepage. I expect it will move into the next volume of the journal proper at some point in the next 3-months. Here are some highlights for those who don’t want to read the paper.

  1. 1st degree relatives of those with ADHD are 2-8 x more likely to also have ADHD than the relatives of people without ADHD.
  2. Many twin studies have reported heritability rates of 71-90%. Note that heritability rates include not only pure genetic influences but gene-environmental interactions. Therefore high heritability rates don’t rule out environmental factors at all.
  3. Five adoption studies in which the similarities of children with ADHD to related and unrelated caregivers have shown high heritability rates. In other words, take a kid with risk of ADHD and place them in an adopted family with little risk and they are still likely to display ADHD.
  4. It’s very important to recognise that you can’t really separate genes and environment and it’s likely that the interaction between both is vital in how all neurodevelopment disorders manifest. For example, genetic risks might lead to ADHD in the presence of environmental factors such as maternal smoking or peer rejection. Or genetically coded risks via child/parent temperament might increase the risk of environmental factors such as maternal smoking or peer rejection.
  5. There are some genetic risks shared between ADHD, dyslexia, autism, conduct disorder, substance mis/use, and mood problems.
  6. There is no single gene involved and the effect sizes for single genes are typically small. What is known about genetic factors in ADHD cannot be used in clinical practice to assess risk or help diagnose.
  7. Thapar et al. remind us that the significance of environmental factors, such as maternal smoking, may have been overrated because it is possible that they have their effects via a gene-environment interaction rather than operating as  a stand-alone environmental variable. They reported that pre- and peri-natal factors like maternal smoking, alcohol and substance misuse were risk factors but not proven causes.  Same goes for lead, pesticides, low birth weight, prematurity and maternal stress. Nutritional deficiencies (e.g., zinc, magnesium) were considered correlates (i.e., they exist together) but have not been proven causal. Same with family adversity and low income and nutritional factors (e.g., high sugar and artificial colourings). Severe early deprivation was considered a likely causal risk factor.

 

 

 

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Cogmed improves working memory scores but not attention or academic skills

October 01st, 2012

ADHD and learning disabilities (LD) co-exist in many children. Many of these students have problems with working memory. Although a little crude, the best description I have for working memory is that it is a set of cognitive functions that help you keep your s@#* together while performing a complex task.

Working memory predicts parent ratings of inattentive behaviours and has been found to be below average in LD and ADHD samples in a large number of studies. It has also been shown to be a predictor of academic success. Previously it had been thought that working memory was a fixed trait. However, recent evidence (see for e.g., Klingberg, 2010; Klingberg et al., 2005) is suggesting that it can be modified via a computerised memory training program called Cogmed. Note that the claim has been that Cogmed improves working memory when all we can really conclude is that a period of training using the program leads to improved scores on tests of working memory. There is an important difference between these two claims.

While there may be evidence for improved working memory scores there is limited evidence of transfer to important functional skills. The sort of transfer one would want to see includes reductions in symptoms of ADHD and improved academic performance in students who have ADHD/LD.

A recent study (Gray et al., 2012) in Journal of Child Psychology & Psychiatry performed a randomised controlled trial on the Cogmed program. 60 adolescents (age 12-17) were recruited from a residential school for students with severe LD and ADHD. Inclusion criteria were (a) full time attendance, (b) diagnosis of LD and ADHD made in the community before entering the school, (c) IQ >80, and (d) English as primary language.  Data from standardised achievement tests indicated that 82% of the sample scored <25th percentile in reading, spelling and maths. 72% of the sample were <25th percentile on the WISC-IV Working Memory Index. Almost all were receiving psychostimulant medication.

Participants were allocated randomly to a Cogmed or maths training group. Working memory tests included digits forward and backward and spatial span, the D2 Test of Attention and the Working Memory Rating Scale. Transfer tests were the WRAT-4 Progress Monitoring Version tests, which includes tests of reading, spelling, maths, and sentence comprehension. Parent and teacher ratings of attention and other symptoms of ADHD were also obtained.

Results showed that the Cogmed group performed better at post-test on the measures of backwards digit span and spatial span. No group differences were found for forwards digit span. Cogmed had no effect on teacher ratings of attention and behaviour. No effects were found for any of the academic measures.

Taken together, the data showed two important things. First, they added to the evidence that working memory is trainable. Second, and this is the most important point, improving working memory via Cogmed did not lead to any improvements in teacher- and parent-rated behaviour or to improvements in any academic skill relative to a group who received maths intervention.

These conclusions are fairly consistent with the whole “brain training” (or as I call it, “neurobabble”) literature. Great claims are made by program developers about improvements in “brain function” but few gains are seen on real-life skills.

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NAPLAN and learning difficulties

June 01st, 2012

May was a busy time in Australian schools with Grades 3, 5, 7 and 9 involved in the national literacy and numeracy tests (NAPLAN). The stress I see in parents and learning support colleagues during NAPLAN time often causes me to reflect on the purpose of the test(s) and how useful they are for students who have learning difficulties.

 The Australian Curriculum, Assessment and Reporting Authority (ACARA) claim that the purpose of NAPLAN is to “measure the literacy and numeracy skills and knowledge that provide the critical foundation for other learning”. They also claim that introduction of NAPLAN has led to “consistency, comparability and transferability of information on students’ literacy and numeracy skills”. (Don Watson would have a field day with these weasel words).
NAPLAN is useful because it identifies students who are struggling with the broad academic skills. Having an objective measurement is important because research has shown that teachers are not particularly accurate in identifying struggling students. For example, Madelaine and Wheldall (2007) randomly selected twelve students from 33 classes and asked their teachers to rank the students based on perceptions of reading performance. They also assessed the students on a passage reading test. Only 50% of teachers identified the same poorest reader as the objective test and only 15% of teachers identified the same three lowest performing readers as the test. We can certainly argue about whether NAPLAN in its current form is the most effective and/or cost-effective method of gathering data on student achievement, however, it seems that we cannot rely on teacher judgment alone.
On the downside, NAPLAN represents a test, not an assessment. All good clinicians and educators know, there is a difference, or should be, between testing and assessment (see here and here). Assessment is a process that starts with the history and clearly defines the presenting problem or set of problems. The clinician develops an hypothesis or set of hypotheses on the basis of the history. They then gather data (e.g., observations, interviews, tests, and base rates) that is designed to shed light on the hypotheses. It is worth noting that a good clinician looks equally for data that confirms and disconfirms the initial hypotheses. Good assessment should lead directly to treatment and/or appropriate teaching for the presenting problem(s) and provide pre-treatment data that allows monitoring of progress. Testing on the other hand simply tells us how good or bad a student is on a particular test. For example, a student with a low score on a reading comprehension test can be said to have poor reading comprehension. The problem with tests is they don’t tell why a student performed poorly and, if they measure a complex process like reading comprehension, writing, or mathematical reasoning, they don’t tell what component of that complex process is weak.
 
That is precisely the problem with NAPLAN. The NAPLAN tasks are complex and provide little information useful for designing interventions for students with learning difficulties and for monitoring response to intervention. An example from NAPLAN illustrates this point.
A mathematics question asked: $4 is shared equally among 5 girls. How much does each girl get? An incorrect response tells us that the student can’t do the task. So what? The child’s teacher probably knew that already. What would be useful would be to know if the student failed the item because (1) they couldn’t read the question, (2) they didn’t know what ‘shared’ or ‘equally’ meant, (3) they didn’t recognise the item required a division operation, (4) they didn’t know to convert $4 to 400c to make the division easier, (5) they didn’t know the fact 40 divided by 5, (6) they knew all of the above but have attention problems and got ‘lost’ during the multi-step division process.
Similarly, if a student performs poorly on the writing component of NAPLAN no information useful for treatment is obtained. The test doesn’t tell us if the child (a) has a form of dyspraxia and struggles with handwriting, (b) has an impoverished spelling lexicon, (c) has poor knowledge of sound-to-letter conversion rules and therefore struggles to spell unfamiliar words, (d) poor knowledge of written grammatical conventions, (e) poor knowledge of written story grammar, (f) oral language weaknesses in semantics and/or grammar, (g) poor oral narrative skills, (h) attention problems so therefore s/he can’t keep his you know what together while doing a complex task, or (i) autism and therefore doesn’t give a toss about the writing topic. The list could go on.
Unfortunately, NAPLAN provides none of these specific data. It simply tells us how bad the child performs relative to some arbitrary benchmark. So where does this leave us? Or more to the point, where does it leave students who have learning difficulties?
Both of which lead me to think that NAPLAN is probably not all that useful for students who have learning difficulties or for the parents, clinicians and teachers who work with them. It also leads me to yearn even more for a Response-to-Intervention approach in which schools recognise learning problems early in the child’s school career, assess to define the problem(s), and provide evidence-based interventions that target the problem(s).
References
Madelaine, A., & Wheldall, K. (2007). Identifying low progress readers: Comparing teacher judgment with a curriculum-based measurement procedure. International Journal of Disability, Development and Education, 52, 33-42.
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Executive Functions & Education

February 07th, 2012

What are Executive Functions?

The Executive Functions (EF) are a set of cognitive functions that provide the infrastructure for acquiring skills and knowledge and that coordinate the production and organisation of that knowledge. They include the ability to inhibit motor responses and other actions, to initiate effort, to sustain attention and effort, to shift attention or strategy, the controls of memory, and the ability to plan and organise for task performance.

Teachers may be more familiar with the term metacognition. This term may be misleading because it creates a false impression of a little meta-person running all cognition or thinking. In fact, the EF are no more or no less important than other cognitive operations and academic skills. The latter can be thought of as the ingredients for a task while the EF provide the recipe. One cannot prepare a meal without the ingredients and the recipe.

Dysfunction in the core EF of behavioural inhibition (the ability to inhibit or stop behavioural responses to stimuli) is now considered to be the a major deficit in Attention-Deficit/Hyperactivity Disorder (ADHD). Executive dysfunction in various forms is also present in a number of other disorders including learning disabilities, Autistic Spectrum Disorders, anxiety disorders and depression.

The adverse effects of executive dysfunction

The EF exist within the brain at a cognitive level and therefore cannot be directly observed. The behaviours that EF dysfunction creates can, however, be observed and include:

  • Having difficulty inhibiting behaviour (i.e., stopping and thinking).
  • Being impulsive, rushing work, and blurting out answers.
  • Failing to pay close attention to details.
  • Having difficulty sustaining mental effort and avoiding tasks that require sustained effort.
  • Being easily distracted and switching from one task to something less important.
  • Difficulty with organisation and planning.
  • Appearing to make the same mistakes repeatedly despite seeming to understand rules and the use of appropriate discipline.
  • Parents and teachers having to continually repeat rules.
  • Some students may manifest hyperactivity verbally (i.e., talk excessively).
  • Becoming fixated on particular things (e.g., television or computer).
  • Failing to learn from previous behaviour and consequences.
  • Only being motivated to perform when there is something in it for them (i.e., they need external motivation).
  • Having poor perception of time and poor ability to use time to plan behaviour.
  • Appearing sluggish and taking a long time to process information.
  • Needing constant assistance in solving problems.
  • Poor short-term memory and general forgetfulness; including forgetting things they need for school or forgetting to hand things in at school.
  • General difficulties with regulating emotion. Emotional responses to situations may appear extreme. It can be difficult for them to remain calm and think things through. They can become overexcited and ‘throw tantrums’ more regularly than their peers.
  • Becoming overwhelmed by tasks that should be manageable.
  • Talking a lot, but not really saying anything.
  • Disorganised speech/language and poor grammar (i.e., their sentences are poorly constructed).
  • These kids have been described as carrying around an excitement meter that they use to evaluate every stimulus in their immediate environment. Essentially, the thing with the highest reading wins (i.e., gets their attention).

Consider the child in a classroom who is faced with both a page of maths problems and his peers talking about BMX bikes. Which stimulus is he to choose? For most kids with EF dysfunction there is no option – they go for the more exciting discussion about BMX. And what happens? They are seen as ‘inattentive’ and in some cases ‘disruptive’. In actual fact, they are being quite attentive to the BMX conversation; it’s just that it may be inappropriate to do so in the classroom.

Once attention has been allocated to an exciting and rewarding stimulus, it can also be hard to get the child to inhibit that response and return to the original task. 

Inconsistency

An individual with EF dysfunction is likely to be inconsistent in academic performance and behaviour; some days they will and some days they won’t, rather than simply not being able to do something at all. They will often have the skills necessary for a task (i.e., the ingredients), but fail to produce adequate performance or output because the EF controls (the  recipe) do not provide the necessary regulation on performance.

Managing Executive Dysfunction

If a child displays some of the symptoms described above and those symptoms are causing them a problem it is appropriate to have them assessed. The psychologist will need to determine what is causing the problems, make the appropriate diagnosis(es) and design a specific treatment plan.

Some individuals, particularly those with a diagnosis of ADHD, may benefit from a stimulant medication or non-stimulant such as atomoxetine. It is important to recognise that medications do not teach skills. They can, however, give the child a greater ability to stop, think, and to perform what they know. Medication does not work for every child but if you consider it worth a trial you should discuss the matter with a medical specialist.

Management of EF should always include a behavioural component and requires a team-based approach. Ideally, the school counsellor and learning support team can assist with management. However, it may be wise to arrange a meeting of all stakeholders at the school to discuss the case. These meetings should be used to further define the problem behaviours within the classroom and to develop methods for improving attention to detail and task and for increasing consistency and output.

More information on EF

lanlfoundation

Lynn Meltzer

National Resource Center on ADHD

Russ Barkley

Russ Barkley 2

 

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