Recent Research Adhd

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** recent research: ADHD

Brain Imaging Identifies Differences in Childhood Bipolar Disorder, ADHD

ScienceDaily (Jan. 19, 2011) — Researchers at the University of Illinois at Chicago are the first to use brain

imaging to examine the effects of emotion on working memory function in children with pediatric bipolar

disorder or attention deficit hyperactivity disorder.

The study is published in the October issue of the Journal of the American Academy of Child & Adolescent Psychiatry .

PBD and ADHD are very severe developmental disorders that share behavioral characteristicssuch as impulsivity, irritability and attention problems.

Using functional magnetic resonance imaging, researchers at UIC examined the brain activity of children as they performed a working memory task while viewing faces with different emotions,such as angry, happy or neutral expressions.

The children, ages 10 to 18, were asked to remember the faces and to press a button in the MR-scanner if they saw the same face that was presented two trials earlier. The study involved 23non-medicated children with bipolar disorder, 14 non-medicated children with ADHD and 19healthy controls.

"It's a simple yet elegant working memory test that tells us a lot about how their brain remembersstimuli like faces or objects," said Alessandra Passarotti, assistant professor of psychiatry at UICand lead author of the study. "We also added in an emotional component -- because bothdisorders show emotional deficits -- to study how their working memory is affected by emotionalchallenge."

The researchers found that while both disorders show dysfunction in the prefrontal cortex relative

to healthy controls, the ADHD group had the most severe dysfunction in this important region.The prefrontal cortex controls behavior, such as impulsivity, and executive function, as well ascomplex cognitive processes such as working memory, attention and language.

From a treatment, learning and intervention perspective, the next step for researchers andclinicians is to figure out how to help patients use their prefrontal cortex, Passarotti said.The researchers also found that while the ADHD group had greater dysfunction in workingmemory circuits in the brain, the bipolar group had more deficits in regions of the brain involved inemotion-processing and regulation.

Now that researchers are starting to differentiate between the two disorders at a brain networklevel, rather than just at a behavioral level, the long-term goal is to develop diagnostic tests basedon neurological and behavioral markers of illness that can be used in a clinical setting. Currentlypatients are diagnosed using clinical measures, questionnaires, behavior scales and interviewswith parents.

It is difficult for physicians to differentiate between the two disorders behaviorally, which may leadto an incorrect diagnosis and wrong medications, a worsening of symptoms, and greater frustration for children and parents, said Passarotti, a researcher in UIC's Institute for JuvenileResearch.She said that while researchers still do not understand all of the neurological deficits thatcharacterize ADHD and PBD profiles, they know that drug treatment that works for ADHD doesnot work for bipolar disorder.



"In fact, if you give a stimulant to a child with bipolar disorder, they become more manic, and thismakes their illness even worse, whereas if you give the mood-regulation medicine commonlyprescribed for PBD to a child with ADHD, they still show a lot of attention deficits and do not showany improvement," Passarotti said.

"Our hope is that by better differentiating between these two severe developmental illnesses, wecan help develop more accurate diagnoses and more targeted treatments for PBD and ADHD."Co-authors of the study are Dr. Mani Pavuluri, the Berger-Colbeth Term Chair in Child Psychiatryand director of the Pediatric Brain Research and Intervention Center at UIC, and John Sweeney,professor of psychiatry, neurology and psychology and director of the Center for CognitiveMedicine at UIC.

Adult ADHD Significantly Increases Risk of Common Form of Dementia

ScienceDaily (Jan. 18, 2011) — Adults who suffer from attention-deficit and hyperactivity disorder (ADHD)

are more than three times as likely to develop a common form of degenerative dementia than those without,according to research in the January issue of the European Journal of Neurology.

Researchers from Argentina confirmed the link during a study of 360 patients with degenerativedementia and 149 healthy controls, matched by age, sex and education. The dementia patientscomprised 109 people with dementia with Lewy bodies (DLB) and 251 with Alzheimer's.

"Our study showed that 48 per cent of patients with DLB -- the second most common cause of degenerative dementia in the elderly after Alzheimer's -- had previously suffered from adult

ADHD" says lead author Dr Angel Golimstok. "This was more than three times the 15 per centrate found in both the control group and the group with Alzheimer's.

"DLB is thought to account for around ten per cent of dementia cases in older people, but it tendsto be under-diagnosed because it shares some characteristics with both Alzheimer's andParkinson's.

"It is a degenerative neurological condition that has a progressive and disabling effect on aperson's mental and physical skills. Other symptoms can include recurrent and realistic visualhallucinations, fluctuations in the person's everyday abilities and spontaneous movementproblems similar to those observed in Parkinson's.

"ADHD is one of the most common behaviour disorders in child and adolescent psychiatry andthe problems it causes, such as difficulty paying attention, hyperactivity and doing thingsimpulsively, can continue into adulthood.

"It is believed that the same neurotransmitter pathway problems are involved in the development

of both conditions, so our research set out to test the theory that adult ADHD often precedesDLB."

The average age of the study subjects was 75 in the DLB group and 74 in the Alzheimer's andcontrol groups. Approximately two-third of the participants were female and length of educationwas very similar. None of the patients were taking psychostimulant drugs.

Patient selection was restricted to people with mild to moderate dementia, measuring 14 to 26 onthe mini mental status examination scale and one to two on the clinical dementia rating scale.



In the healthy controls, previous ADHD symptoms were assessed using information from thesubjects and direct informants. In patients with cognitive impairment, the assessment was basedon symptoms described by direct informants who had known the patient for at least 10 years andhad information obtained from a close relative who knew the patient in childhood.

Two neurologists, who were unaware of the objectives of the study, were independently asked toassess all the patients for adult ADHD using:

• the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV),

which has been produced by the American Psychiatric Association to diagnose psychiatricdisorders

• the validated Wender Utah Rating Scale, which is specially designed to retrospectively

assess ADHD.

This produced agreement levels of 98 per cent in the DLB group, 96 per cent in the Alzheimer'sgroup and 97.5 per cent in the control group.

A third neurologist provided their judgement in the small number of cases where the first twodisagreed and a diagnosis of ADHD was recorded if two out of the three neurologists agreed. Theresults were then checked by a fourth neurologist fully informed about the objectives of the study.

These results provided an overall diagnosis of previous adult ADHD for the two dementia groupsand the control. They also showed that impulsivity and hyperactivity, which are major symptomsof ADHD, were significantly higher in the DLB group than the Alzheimer's group and the controlgroup (measuring 14.7, 5.9 and 6.4 respectively on the Wender Utah Rating Scale).

"We believe that our study is the first of its kind to examine the clinical association between adult ADHD symptoms and DLB and that it has established a clear link between the two conditions"says Dr Golimstok.

"Our theory is that this association can be explained by the common neurotransmitter dysfunctionpresent in both conditions. There is clearly a common process involved in both illnesses and itappears that ADHD often develops into DLB as the patient ages."

Brain Scans Show Children With ADHD Have Faulty Off-Switchfor Mind-Wandering

ScienceDaily (Jan. 10, 2011) — Brain scans of children with attention-deficit/hyperactivity disorder (ADHD)

have shown for the first time why people affected by the condition sometimes have such difficulty in

concentrating. The study, funded by the Wellcome Trust, may explain why parents often say that their child

can maintain concentration when they are doing something that interests them, but struggles with boring

tasks.

Using a 'Whac-a-Mole' style game, researchers from the Motivation, Inhibition and Developmentin ADHD Study (MIDAS) group at the University of Nottingham found evidence that children with

ADHD require either much greater incentives -- or their usual stimulant medication -- to focus ona task. When the incentive was low, the children with ADHD failed to "switch off" brain regionsinvolved in mind-wandering. When the incentive was high, however, or they were taking their medication, their brain activity was indistinguishable from a typically-developing non-ADHD child.

ADHD is the most common mental health disorder in childhood, affecting around one in 50children in the UK. Children with ADHD are excessively restless, impulsive and distractible, andexperience difficulties at home and in school. Although no cure exists for the condition, symptoms



can be reduced by medication and/or behavioural therapy. The drug methylphenidate (more oftenknown by the brand name Ritalin) is commonly used to treat the condition.

Previous studies have shown that children with ADHD have difficulty in 'switching-off' the defaultmode network (DMN) in their brains. This network is usually active when we are doing nothing,giving rise to spontaneous thoughts or 'daydreams', but is suppressed when we are focused onthe task before us. In children with ADHD, however, it is thought that the DMN may beinsufficiently suppressed on 'boring' tasks that require focused attention.

The MIDAS group researchers compared brain scans of eighteen children with ADHD, agedbetween nine and fifteen years old, against scans of a similar group of children without thecondition as both groups took part in a task designed to test how well they were able to controltheir behaviour. The children with ADHD were tested when they were taking their methylphenidate and when they were off their medication. The findings are published inthe Journal of Child Psychology and Psychiatry .

Whilst lying in a magnetic resonance imaging (MRI) scanner, which can be used to measureactivity in the brain, the children played a computer game in which green aliens were randomlyinterspersed with less frequent black aliens, each appearing for a short interval. Their task was to'catch' as many green aliens as possible, while avoiding catching black aliens. For each slow or

missed response, they would lose one point; they would gain one point for each timely response.To study the effect of incentives, the reward for avoiding catching the black alien was thenincreased to five points, with a five-point penalty incurred for catching the wrong alien.

By studying the brain scans, the researchers were able to show that typically developing childrenswitched off their DMN network whenever they saw an item requiring their attention. However,unless the incentive was high, or they had taken their medication, the children with ADHD wouldfail to switch off the DMN and would perform poorly. This effect of incentives was not seen inchildren without ADHD -- activity in their DMN was switched off by items requiring their attentionregardless of the incentive on offer.

Professor Chris Hollis, who led the study, says: "The results are exciting because for the first timewe are beginning to understand how in children with ADHD incentives and stimulant medication

work in a similar way to alter patterns of brain activity and enable them to concentrate and focusbetter. It also explains why in children with ADHD their performance is often so variable andinconsistent, depending as it does on their interest in a particular task."

Dr Martin Batty, co-author of the study, adds: "Using brain imaging, we have been able to seeinside the children's heads and observe what it is about ADHD that is stopping them isconcentrating. Most people are able to control their 'daydreaming' state and focus on the task athand. This is not the case with children with ADHD. If a task is not sufficiently interesting, theycannot switch off their background brain activity and they are easily distracted. Making a taskmore interesting -- or providing methylphenidate -- turns down the volume and allows them toconcentrate."

Dr Elizabeth Liddle, first author of the study, says that these findings help explain one of the

interesting characteristics of ADHD -- that children with the condition appear able to controlthemselves much better when motivated to do so.

"The common complaint about children with ADHD is that 'he can concentrate and control himself fine when he wants to', so some people just think the child is being naughty when hemisbehaves," says Dr Liddle. "We have shown that this may be a very real difficulty for them. Theoff-switch for their 'internal world' seems to need a greater incentive to function properly and allowthem to attend to their task."

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