Working memory (WM) is the cognitive system responsible for the temporary storage and manipulation of information and plays an important role in both learning and focusing attention. Considerable research has documented that many children and adults with ADHD have WM deficits and that this contributes to difficulties associated with the disorder. For an excellent introduction to the role of WM deficits in ADHD, click here.

A simple example illustrates the importance of WM for particular academic tasks. Try adding 3 and 9 in your head. That was probably easy for you. Now trying adding 33 and 99. That was probably more difficult. Finally, try adding 333 and 999. This is quite challenging for most adults even though each calculation required is trivially easy. The challenge occurred because you need to store information – the sum of 3+9 in the one’s column and then ten’s column – as you process the remaining part of the problem, i.e., 3+9 in the hundred’s column, and this taxed your WM. If your WM capacity was exceeded, you could not complete the problem successfully.

This simple problem also illustrates the difference between short-term memory (STM) and WM. Short-term memory simply involves retaining information in mind for short periods of time, e.g., remembering that the problem you need to solve is 333+999. Working memory, in contrast, involves mentally manipulating – or ‘working’ with – retained information and comes into play in a wide range of learning activities. For example, to answer questions about a science chapter, a child not only has to correctly retain factual information but must mentally work with that information to answer questions about it. Thus, when a child’s WM capacity is low relative to peers, academic performance is likely to be compromised in multiple areas.

Because WM deficits play an important role in the struggles experienced by many individuals with ADHD, it is important to consider how different interventions address this aspect of the disorder. In this study, the authors were interested in comparing the impact of Working Memory Training and stimulant medication treatment on the WM performance of children diagnosed with ADHD.

Participants were 25 8-11 year-old children with ADHD (21 boy and 4 girls) who were being treated with stimulant medication. Children’s memory performance was assessed on 4 occasions using the Automated Working Memory Assessment (AWMA), a computerized test that measures verbal short-term memory, verbal working memory, visuo-spatial short-term memory, and visuo-spatial working memory.

At time 1, the assessment was conducted when children had been off medication for at least 24 hours. The second assessment occurred an average of 5 months later and when children were on medication. The third assessment occurred after children had completed 5 weeks of Cogmed Working Memory Training using the standard training protocol (see below). The final assessment occurred approximately 6 months after training had ended. This design enabled the researchers to make the following comparisons:

- WM performance on medication vs. off medication (T1 vs T2)
- WM performance on medication vs. after training (T2 vs. T3)
- WM performance immediately after training ended vs. 6 months following training (T3 vs. T4)

This final comparison provided information on whether any benefits provided by the training had endured.

In addition to measuring STM and WM at each time point, measures of IQ were collected at times 1, 2, and 3.

- Working Memory Training -

WM training was conducted using the standard Cogmed training protocol with each child completing 20-25 training sessions within a 25 day period. The training requires the storage and manipulation of sequences of verbal, e.g., repeating back a sequence of digits in reverse order, and/or visuo-spatial information, e.g., recalling the location of objects on different portions of the computer screen.

Difficulty level is calibrated on a trial by trial basis so the child is always working at a level that closely matches their performance. For example, if a child successfully recalled three digits in reverse order, on the next trial he had to recall four. When a trial was failed, the next trial was made easier by reducing the number of items to be recalled. This method of ‘adaptive training’ is thought to be a key element because it requires the child to ’stretch’ their WM capacity to move through the program.

- Results -

- Impact of Short-Term Memory and Working Memory -

Medication vs. no medication – When tested on medication, Read the rest of this entry »

There’s such a flood of very significant research studies, educational resources and articles related to brain health, it’s hard to keep track – even for us!

Let me introduce and quote some of the top Brain Health Studies, Articles and Resources published in March:

1) Cognitive Decline Begins In Late 20s, Study Suggests (Science Daily)

- “These patterns suggest that some types of mental flexibility decrease relatively early in adulthood, but that how much knowledge one has, and the effectiveness of integrating it with one’s abilities, may increase throughout all of adulthood if there are no pathological diseases,” Salthouse said.

- However, Salthouse points out that there is a great deal of variance from person to person

2) Cerebrum 2009: Emerging Ideas in Brain Science – new book by the Dana Foundation that “explores the cutting edge of brain research and its implications in our everyday lives, in language understandable to the general reader.”

A couple of excellent chapters of direct relevance to everyone’s brain health are:
- Chapter 4: A Road Paved by Reason, by Elizabeth Norton Lasley

- Chapter 10: Neural Health: Is It Facilitated by Work Force Participation?, by Denise Park, Ph.D

3) Staying Sharp DVD Program: “Dr. Jordan Grafman, chief of the Cognitive Neuroscience Section at the National Institute of Neurological Disorders and Stroke outside of Washington, DC, and a member of the Dana Alliance for Brain Initiatives, is your guide as we cover what to expect from the aging brain and what we can do to ’stay sharp.’

For a free DVD of this program you can contact stayingsharp@dana.org. (they say free in their website, I don’t know if that includes shipping & handling)

4) Drivers to be tested on cognitive ability starting at age 75 (Japan Times)

The outline of a cognitive test that drivers aged 75 or over will be required to take from June when renewing their licenses was released Thursday…The test is intended to reduce the number of traffic accidents involving elderly drivers by measuring their cognitive level.

5) Physical Fitness Improves Spatial Memory, Increases Size Of Brain Structure (Science Daily)

- “Now researchers have found that elderly adults who are more physically fit tend to have bigger hippocampi and better spatial memory than those who are less fit.”

6) Brain Trainers: A Workout for the Mind (Scientific American Mind)

“I recently tried out eight of the latest brain fitness programs, training with each for a week. The programs ranged widely in focus, quality and how fun they were to use. “Like physical exercise equipment, a brain exercise program doesn’t do you any good if you don’t use it,” says Andrew J. Carle, director of the Program in Assisted Living/Senior Housing Administration at George Mason University. And people tend not to use boring equipment. “I remember when NordicTrack was the biggest thing out there. Everyone ran out and bought one, and 90 percent of them ended up as a clothes rack in the back of your bedroom.”

The reporter used: Posit Science’s Brain Fitness Program Classic, HappyNeuron, Nintendo BrainAge, CogniFit’s MindFit/ CogniFit Personal Coach, Lumosity, MyBrainTrainer, BrainTwister, Cogmed Working Memory Training.

7) The Latest in Mental Health: Working Out at the ‘Brain Gym’ (Wall Street Journal)

- “Marshall Kahn, an 82-year-old family doctor in Fullerton, Calif., says he got such a boost from brain exercises he started doing at a “Nifty after Fifty” club that he decided to start seeing patients again part-time. “Doing all the mental exercise,” he says, “I realized I’ve still got it.”

Debate Over Drugs For ADHD Reignites (Washington Post)

- “New data from a large federal study have reignited a debate over the effectiveness of long-term drug treatment of children with hyperactivity or attention-deficit disorder, and have drawn accusations that some members of the research team have sought to play down evidence that medications do little good beyond 24 months.”

- “The study also indicated that long-term use of the drugs can stunt children’s growth.”

Adaptive training leads to sustained enhancement of poor working memory in children (Developmental Science)

Abstract: Working memory plays a crucial role in supporting learning, with poor progress in reading and mathematics characterizing children with low memory skills. This study investigated whether these problems can be overcome by a training program designed to boost working memory. Children with low working memory skills were assessed on measures of working memory, IQ and academic attainment before and after training on either adaptive or non-adaptive versions of the program. Adaptive training that taxed working memory to its limits was associated with substantial and sustained gains in working memory, with age-appropriate levels achieved by the majority of children. Mathematical ability also improved significantly 6 months following adaptive training. These findings indicate that common impairments in working memory and associated learning difficulties may be overcome with this behavioral treatment.

9) Brain cortex thinning linked to inherited depression (Los Angeles Times)

- “On average, people with a family history of depression appear to have brains that are 28% thinner in the right cortex — the outermost layer of the brain — than those with no known family history of the disease. That cortical thinning, said the researchers, is on a scale similar to that seen in patients with Alzheimer’s disease or schizophrenia.”

We have all heard about children who have Attention Deficit/Hyperactivity Disorder (AD/HD). Indeed, this condition seems to affect 5 to 8% of school age children. Have you ever wondered what happen to these children? As many as 60% of them become adults presenting AD/HD symptoms! Ron de Graaf and colleagues recently published a study in which they found that an average of 3.5% of workers (in ten countries) meet the criteria for adult ADHD. As you can imagine, being an adult with AD/HD can be a challenge at work.

Before we explore this issue let’s start by describing the symptoms of ADHD.

What is adult AD/HD?

AD/HD is a disorder of the brain. Research clearly indicates that AD/HD is to a large extent genetic, that is it tends to run in families. However, AD/HD is a complex disorder and other causal factors may be at play.

Typically, the symptoms arise in early childhood, unless they are associated with some type of brain injury later in life. Some people have mild AD/HD with only a few symptoms while others have more serious AD/HD with more symptoms.

Symptoms of inattention (adapted from the DSM-IV)

Read the rest of this entry »