Autism: Biological basis for sensory processing disorders in children

The image shows areas of the brain that can be affected by sensory processing disorders. 

Using an advanced form of MRI, researchers at UCSF have identified abnormalities in the brain structure of children with SPD primarily in the back of the brain.

Sensory processing disorders (SPD) are more prevalent in children than autism and as common as attention deficit hyperactivity disorder, yet it receives far less attention partly because it's never been recognized as a distinct disease.

In a groundbreaking new study from UC San Francisco, researchers have found that children affected with SPD have quantifiable differences in brain structure, for the first time showing a biological basis for the disease that sets it apart from other neurodevelopmental disorders.

One of the reasons SPD has been overlooked until now is that it often occurs in children who also have ADHD or autism, and the disorders have not been listed in the Diagnostic and Statistical Manual (DSM-5) used by psychiatrists and psychologists.

"Until now, SPD hasn't had a known biological underpinning," said senior author Pratik Mukherjee, MD, PhD, a professor of radiology and biomedical imaging and bioengineering at UCSF.

"Our findings point the way to establishing a biological basis for the disease that can be easily measured and used as a diagnostic tool," Mukherjee said.

The work is published in the open access online journal NeuroImage:Clinical -  'Abnormal white matter microstructure in children with sensory processing disorders'

'Out of Sync' Kids
Sensory processing disorders affect 5 to 16 percent of school-aged children.

Children with SPD struggle with how to process stimulation, which can cause a wide range of symptoms including hypersensitivity to sound, sight and touch, poor fine motor skills and easy distractibility.

Some SPD children cannot tolerate the sound of a vacuum, while others can't hold a pencil or struggle with social interaction.

Furthermore, a sound that one day is an irritant can the next day be sought out. The disease can be baffling for parents and has been a source of much controversy for clinicians, according to the researchers.

"Most people don't know how to support these kids because they don't fall into a traditional clinical group," said Elysa Marco, MD, who led the study along with postdoctoral fellow Julia Owen, PhD.

Marco is a cognitive and behavioral child neurologist at UCSF Benioff Children's Hospital, ranked among the nation's best and one of California's top-ranked centers for neurology and other specialties.

These brain images, taken with DTI, show water diffusion within the white matter of children with sensory processing disorders. 

Row FA: The blue areas show white matter where water diffusion was less directional than in typical children, indicating impaired white matter microstructure. 

Row MD: The red areas show white matter where the overall rate of water diffusion was higher than in typical children, also indicating abnormal white matter.

Row RD: The red areas show white matter where SPD children have higher rates of water diffusion perpendicular to the axonal fibers, indicating a loss of integrity of the fiber bundles comprising the white matter tracts.

"Sometimes they are called the 'out of sync' kids. Their language is good, but they seem to have trouble with just about everything else, especially emotional regulation and distraction. In the real world, they're just less able to process information efficiently, and they get left out and bullied," said Marco, who treats affected children in her cognitive and behavioral neurology clinic.

"If we can better understand these kids who are falling through the cracks, we will not only help a whole lot of families, but we will better understand sensory processing in general. This work is laying the foundation for expanding our research and clinical evaluation of children with a wide range of neurodevelopmental challenges – stretching beyond autism and ADHD," she said.

Imaging the brain's white matter
In the study, researchers used an advanced form of MRI called diffusion tensor imaging (DTI), which measures the microscopic movement of water molecules within the brain in order to give information about the brain's white matter tracts.

DTI shows the direction of the white matter fibers and the integrity of the white matter. The brain's white matter is essential for perceiving, thinking and learning.

The study examined 16 boys, between the ages of eight and 11, with SPD but without a diagnosis of autism or prematurity, and compared the results with 24 typically developing boys who were matched for age, gender, right- or left-handedness and IQ.

The patients' and control subjects' behaviours were first characterized using a parent report measure of sensory behavior called the Sensory Profile.

The imaging detected abnormal white matter tracts in the SPD subjects, primarily involving areas in the back of the brain, that serve as connections for the auditory, visual and somatosensory (tactile) systems involved in sensory processing, including their connections between the left and right halves of the brain.

"These are tracts that are emblematic of someone with problems with sensory processing," said Mukherjee.

"More frontal anterior white matter tracts are typically involved in children with only ADHD or autistic spectrum disorders. The abnormalities we found are focused in a different region of the brain, indicating SPD may be neuroanatomically distinct."

The researchers found a strong correlation between the micro-structural abnormalities in the white matter of the posterior cerebral tracts focused on sensory processing and the auditory, multisensory and inattention scores reported by parents in the Sensory Profile.

The strongest correlation was for auditory processing, with other correlations observed for multi-sensory integration, vision, tactile and inattention.

The abnormal microstructure of sensory white matter tracts shown by DTI in kids with SPD likely alters the timing of sensory transmission so that processing of sensory stimuli and integrating information across multiple senses becomes difficult or impossible.

"We are just at the beginning, because people didn't believe this existed," said Marco. "This is absolutely the first structural imaging comparison of kids with research diagnosed sensory processing disorder and typically developing kids. It shows it is a brain-based disorder and gives us a way to evaluate them in clinic."

Future studies need to be done, she said, to research the many children affected by sensory processing differences who have a known genetic disorder or brain injury related to prematurity.

The study's co-authors are Shivani Desai, BS, Emily Fourie, BS, Julia Harris, BS, and Susanna Hill, BS, all of UCSF, and Anne Arnett, MA, of the University of Denver.

Reactive Attachment Disorder (RAD) in childhood

Dr Minnis

Dr Minnis is a Senior Lecturer in Child and Adolescent Psychiatry. Her main research interest is in Reactive Attachment Disorder in childhood and her research has involved developing new assessment tools and increasing understanding of the aetiology of this serious disorder of social functioning.

She has also developed computerised assessment tools for aspects of child and adolescent mental health.

Background
Reactive attachment disorder (RAD) is described in clinical literature as a severe and relatively uncommon disorder that can affect children.

There is potentially a higher level of incidence in homes where the family is long-term unemployed and there is a history of social care provision but RAD can also occur in, what is believed to be, the best of family situations.

RAD is characterised by markedly disturbed and developmentally inappropriate ways of relating socially in most contexts.

It can take the form of a persistent failure to initiate or respond to most social interactions in

• a developmentally appropriate way, known as the "inhibited form," (RAD) or
• an indiscriminate sociability, such as excessive familiarity with relative strangers known as the "disinhibited form" (DAD). 

The term is used in both the World Health Organization's International Statistical Classification of Diseases and Related Health Problems (ICD-10) and in the DSM-IV-TR, the revised fourth edition of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM).

ICD-10 Definition
In ICD-10, the inhibited form is called RAD, and the disinhibited form is called "disinhibited attachment disorder", or "DAD".

DSM Definition
In the DSM, both forms are called RAD; for ease of reference, this article will follow that convention and refer to both forms as reactive attachment disorder.

RAD arises from a failure to form normal attachments to primary caregivers in early childhood. Such a failure could result from severe early experiences of neglect, abuse, abrupt separation from caregivers between the ages of six months and three years, frequent change of caregivers, or a lack of caregiver responsiveness to a child's communicative efforts. Not all, or even a majority of such experiences, result in the disorder.

The criteria for a diagnosis of a Reactive Attachment Disorder are very different from the criteria used in assessment or categorisation of attachment styles such as insecure or disorganised attachment, e.g. Pervasive Development Disorder (PDD).

PDD: Pervasive Development Disorder
It is differentiated and has a separate classification from Pervasive Developmental Disorder (PDD) or developmental delay and from possibly comorbid conditions such as mental retardation, all of which can affect attachment behaviour.

Dr Minnis appeared on BBC Radio 4's Women's hour program to discuss RAD with the presenter and families that had suffered from the experience of having a teenager with RAD.

International Experts Resign From flawed DSM-5 Working group

Roel Verheul

Roel Verheul (Amsterdam) and John Livesley (Canada) both felt compelled to resign from the DSM-5 Personality Disorders Work Group. Here is an email from them describing what went wrong in the preparation of this section:

"We resigned from the DSM-5 Personality and Personality Disorder Work Group in April 2012 with a mixture of sadness and regret.

We believed that the construction of DSM-5 afforded an important opportunity to advance the study of personality disorder by developing an evidence-based classification with greater clinical utility than DSM-IV.

John Livesley

The data and conceptual tools for such an undertaking have been available for some time and the field seemed to recognize the need for change.

Regrettably, the Work Group has been unable to capitalize on the opportunity and has advanced a proposal that is seriously flawed.

It has also demonstrated an inability to respond to constructive feedback both from within the Work Group and from the many experts in the field who have communicated their concerns directly and indirectly.

We also regret the need to resign because we were the only International members of the Work Group which is now without representation from outside the US."

Read the full article here: Two Who Resigned From DSM-5 Explain Why

The Dyslexia Dilemma – Continued

If dyslexia is a gift, perhaps it does not belong in a manual for diagnosing psychiatric disorders at all. The full title of the DSM is Diagnostic and Statistical Manual of Mental Disorders. 

The book is in essence a psychiatrist’s bible, the ultimate guide on how to figure out and label whatever is wrong mentally or emotionally with the psychiatrist’s patients.

Over-inclusive language and labeling in the DSM has been criticized by many as contributing to over-medication — and over medicalization  - of conditions that may be part of the normal ups and downs of life.

One study reported that half of US teens met the criteria for diagnosis of a mental disorder. In that context, a diagnosis opens the doors to prescribing of powerful drugs that may do more harm than good, especially to a a growing child.

Although the goal of inclusion of the term dyslexia into a diagnostic manual is to make it easier for individuals to get recognition and help for their difficulties, the flip side is that the label can come with a stigma, or be used as a barrier.

As long as dyslexia is deemed a “disorder,” educators and employers will continue to look at dyslexics as being less capable and less deserving of advancement.

Perhaps the time has come to recognize that “dyslexia” is a characteristic, not a disease. Because it is common — perhaps impacting as many as 20% of all schoolchildren to some degree — maybe it should be the responsibility of educators to learn how to teach children with dyslexic characteristics within the normal classroom environment.

That is, perhaps parents should be relieved of the educational burden of proving that there is something wrong with their children in order to get specialized services.

The burden should shift to educators to learn to reach and teach all of their students, not just the ones who have “average” or “typical” learning styles.

The need for “diagnosis” only arises because of educational and societal barriers. Within a school context, a child is only referred for “diagnosis” because it is apparent that the child is struggling and falling behind.

But all a dyslexia diagnosis does, especially with the language now proposed by the APA for “Specific Learning Disorder”, is to confirm what the parents and educators already know: that the child is indeed struggling and falling behind.

There is not one word in the current proposed diagnostic standard, with or without the use of the term “dyslexia”, that would shed light on the reasons for the student’s struggle or point the way to a specific path to address the learning difficulties. Instead, it is “diagnosis” that relies entirely on circular reasoning.

A child who has difficulties in acquiring basic academic skills would be referred to a psychologist or psychiatrist, who would then report back that the child indeed has difficulties acquiring basic skills.

Perhaps it is time to dispense with the idea of “diagnosing” a medical condition, and to recognize that “dyslexia” is a legitimate and important way to describe a particular profile of learning strengths and weaknesses.

Perhaps it is time to move beyond blaming the student for what is really a failure of the educational system to address the needs of all learners.

The Dyslexia Dilemma - Redefined

The term dyslexia was coined in 1887 by a German ophthalmologist, Rudolph Berlin. But there exists no standard for diagnosis. The DSM IV defined “Reading Disorder” broadly as “Reading achievement,… substantially below that expected given the person’s chronological age, measured intelligence, and age-appropriate education.” (DSM IV – 315.00)

An early draft of the forthcoming DSM V filled this gap with a simple definition. The term “Dyslexia” was added to be “consistent with international use”. (A 13 Proposed Revision Rationale).

The condition was described broadly as “Difficulties in accuracy or fluency of reading that are not consistent with the person’s chronological age, educational opportunities, or intellectual abilities.”

However, the APA has now retreated from this position, eliminating the term dyslexia from their recommendation entirely: “Learning Disorder has been changed to Specific Learning Disorder, and the previous types of Learning Disorders (Dyslexia, Dyscalculia, and Disorder of Written Expression) are no longer being recommended.”  (See Neurodevelopmental Disorders.)

The text of the newly defined  Specific Learning Disorder will exclude thousands from consideration or diagnosis, by interposing a diagnostic requirement: that “current skill level” be “well-below the average range.”

This means that higher functioning dyslexics will never have the benefit of a diagnosis. As happened with my own son, they will be deemed to be “lazy” despite the hours they put in to attain barely-average functional skill levels.

Those whose skill level is sufficiently depressed to qualify will lose their diagnosis at the moment any form of intervention is successful. It won’t matter how hard they struggle to get there; the moment their reading scores begin to approach “average” their diagnosis will evaporate. It is likely that whatever support or accommodations have enabled their improved skills will also be withdrawn as well.

This is a political determination, not a scientific one — very much at odds with a growing body of brain research showing that dyslexia is neurologically-based.

The APA will allow comments on the new proposal until June 15, 2012.  Anybody can register at the APA web site at www.dsm5.org and post.   

If you are not happy with the proposal, I urge you to take the time in the next few days to do so.

New Diagnostic Guidelines for DSM: The Manual for Mental Disorders

New Diagnostic Guidelines for Mental Illnesses Proposed - BusinessWeek

For the first time in more than a decade, the American Psychiatric Association has announced proposed changes to the Diagnostic and Statistical Manual of Mental Disorders (DSM), long considered the "Bible" of psychiatry.

Unlike its predecessor, DSM-4, the new DSM-5 would not formally recognize sex and Internet addictions; would create a new category for "risk" disorders for people possibly heading towards developing full psychosis or dementia; and would create a new disorder, "temper dysregulation with dysphoria" (TDD) to incorporate both mood and behavioral disturbances, partly a response to current overdiagnosis of juvenile bipolar disorder.

Other issues were also addressed, including creating an overarching category known as "autism spectrum disorders" to encompass autism, Asperger's syndrome and other similar conditions. This term is already widely used. And "mental retardation" would become "intellectually challenged."

DSM is the tome used by psychiatrists and other mental health professionals to diagnose different conditions and to guide research.

The proposed draft will be available for public comment until April 20. The final document, which has already been 10 years in the making, is expected to be released in 2013. The DSM-4 was published in 1994.

One of the major changes in the proposed volume will be a move toward "dimensional assessments" for mental disorders, meaning that strict, immutable categories will be replaced by a reliance on continuums and that "cross-cutting" symptoms -- those that span several different disorders -- will be included in the criteria.

"There's no measure in the [DSM-4] to account for the severity of the disorder and therefore no way to measure if a patient, on quantitative measures, is improving with treatment," Dr. Darrel Regier, vice chair of the DSM-5 Task Force and director of research for the American Psychiatric Association, said during a Tuesday teleconference announcing the proposed changes. "We're trying to address this with more quantitative measures on a continuum with a cut-off to decide mild, severe, very severe."

This time around, experts say they are giving "careful consideration" to how mental health disorders might vary according to race, gender and ethnicity.