Thursday, 30 September 2010

ADHD and Genetics.

Many of you will have seen the media reports this morning of the research which according to the headlines, proves that ADHD is caused by faulty DNA.  For those of you who have not, here is the link to the BBC version of the story.  http://www.bbc.co.uk/news/health-11437079 

On the face of it, this is good research, but again the media rush to generalisation. Yes,faulty DNA might have been found in 15% of the children in the ADHD group. The question is does that mean that faulty DNA is the cause of ADHD in ALL children who have it? The answer is NO!   ADHD is a destination to which there is more than one ...route. Yes the genetic route is travelled by some children, this study proves so, - but there are other routes too.  For instance, both pesticide use and food additives have been implicated in some cases of ADHD.  At Snowdrop we see children who have ADHD as a consequence of brain injury too.

We should also not forget that genes are only able to express themselves when the correct environmental conditions exist for them to do so, - so environmental factors are to blame even in a genetic cause.

Monday, 27 September 2010

ADHD. - Hyperactivity might be an essential part of learning.

This important study will help to inform and develop what is already Snowdrop's extensive range of techniques to help children with ADHD.


A new University of Central Florida study may explain why children with attention deficit hyperactivity disorder move around a lot – it helps them stay alert enough to complete challenging tasks.
In studies of 8- to 12-year-old boys, Psychology Professor Mark D. Rapport found that children with and without ADHD sat relatively still while watching Star Wars and painting on a computer program.
All of the children became more active when they were required to remember and manipulate computer-generated letters, numbers and shapes for a short time. Children with ADHD became significantly more active – moving their hands and feet and swiveling in their chairs more – than their typically developing peers during those tasks.

Rapport's research indicates that children with ADHD need to move more to maintain the required level of alertness while performing tasks that challenge their working memory. Performing math problems mentally and remembering multi-step directions are examples of tasks that require working memory, which involves remembering and manipulating information for a short time.

"We've known for years that children with ADHD are more active than their peers," said Rapport, whose findings are published in the Journal of Abnormal Child Psychology. "What we haven't known is why."
"They use movement to keep themselves alert," Rapport added. "They have a hard time sitting still unless they're in a highly stimulating environment where they don't need to use much working memory."

Rapport compared the children's movements during the tests to adults' tendency to fidget and move around in their chairs to stay alert during long meetings.

The findings have immediate implications for treating children with ADHD. Parents and educators can use a variety of available methods and strategies to minimize working memory failures. Providing written instructions, simplifying multi-step directions, and using poster checklists can help children with ADHD learn without overwhelming their working memories.

"When they are doing homework, let them fidget, stand up or chew gum," he said. "Unless their behavior is destructive, severely limiting their activity could be counterproductive."

Rapport's findings may also explain why stimulant medications improve the behavior of most children with ADHD. Those medications improve the physiological arousal of children with ADHD, increasing their alertness. Previous studies have shown that stimulant medications temporarily improve working memory abilities.

Rapport's research team studied 23 boys, including 12 who were diagnosed with ADHD. Each child took a variety of tests at the UCF Children's Learning Clinic on four consecutive Saturdays. Devices called actigraphs placed on both ankles and the non-dominant hand measured the frequency and intensity of each child's movement 16 times per second. The children were told they were wearing special watches that allowed them to play games.

In the first of the two published studies, the research team demonstrated that children with ADHD have significantly impaired visual and verbal working memory compared with their typically developing peers. In one test, the children were asked to reorder and recall the locations of dots on a computer screen. Compared with their typically developing peers, the children with ADHD performed much worse on that test – and on a similar one requiring them to reorder and recall sequences of numbers and letters.

The second study focused on the frequency and intensity of movement by the children while they were taking those two tests.

Thursday, 16 September 2010

Proof that the Brain is Plastic!

For twenty years now, many people working in the field of neuroscience, including myself have been saying that the brain is capable of re-wiring itself. Twenty years ago, the medical professionals I said it to laughed at me and gave me the sort of looks, which are usually reserved for those who are 'not quite right in the head.' Ten years ago, they smiled and looked in disbelief.   Today, we have actual evidence. Snowdrop has been utilising this principle within it's programmes for children with cerebral palsy, autism and other developmental disabilities, since it was established. Read on.
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Scientists in Tübingen have proven for the first time that widely-distributed networks of nerves in the brain can fundamentally reorganize as required

Scientists at the Max Planck Institute for Biological Cybernetics in Tübingen have succeeded in demonstrating for the first time that the activities of large parts of the brain can be altered in the long term. The breakthrough was achieved through the experimental stimulation of nerve cells in the hippocampus. Using a combination of functional magnetic resonance tomography, microstimulation and electrophysiology, the scientists were able to trace how large populations of nerve cells in the forebrain reorganise. This area of the brain is active when we remember something or orient ourselves spatially. The insights gained here represent the first experimental proof that large parts of the brain change when learning processes take place.

Scientists refer to the characteristic whereby synapses, nerve cells or entire areas of the brain change depending on their use as neuronal plasticity. It is a fundamental mechanism for learning and memory processes. The explanation of this phenomenon in neuronal networks with shared synapses reaches as far back as the postulate of Hebbian learning proposed by psychologist Donald Olding Hebb in 1949: when a nerve cell  'A' permanently and repeatedly stimulates another nerve cell 'B', the synapse is altered in such a way that the signal transmission becomes more efficient. The membrane potential in the recipient neuron increases as a result. This learning process, whose duration can range from a few minutes to an entire lifetime, was intensively researched in the hippocampus.

A large number of studies have since shown that the hippocampus plays an important role in memory capacity and spatial orientation in animals and humans. Like the cortex, the hippocampus consists of millions of nerve cells that are linked via synapses. The nerve cells communicate with each other through so-called "action potentials": electrical impulses that are sent from the transmitter cells to the recipient cells. If these action potentials become more frequent, faster or better coordinated, the signal transmission between the cells may be strengthened, resulting in a process called long-term potentiatation (LTP), whereby the transmission of the signal is strengthened permanently. The mechanism behind this process is seen as the basis of learning.

Although the effects of long-term potentiation within the hippocampus have long been known, up to now it was unclear how synaptic changes in this structure can influence the activities of entire neuronal networks outside the hippocampus, for example cortical networks. The scientists working with Nikos Logothetis, Director at the Max Planck Institute for Biological Cybernetics, have researched this phenomenon systematically for the first time. What is special about their study is the way in which it combines different methods: while the MRI scanner provides images of the blood flow in the brain and, therefore, an indirect measure of the activity of large neuronal networks, electrodes in the brain measure the action potentials directly, and therefore the strength of the nerve conduction. It emerged from the experiments that the reinforcement of the stimulation transmission generated in this way was maintained following experimental stimulation. 


"We succeeded in demonstrating long-term reorganization in nerve networks based on altered activity in the synapses," explains Dr. Santiago Canals. 

The changes were reflected in better communication between the brain hemispheres and the strengthening of networks in the limbic system and cortex. While the cortex is responsible for, among other things, sensory perception and movement, the limbic system processes emotions and is partly responsible for the emergence of instinctive behavior.
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Snowdrop even published information about this in our book, two years ago. Visit our website to learn more.

Wednesday, 15 September 2010

Can a Head Injury Cause Autism?

This is a question which arises again and again, it's other form is 'Can brain injury cause autism?' In my opinion, having seen many children who have suffered brain injuries, who also display symptoms which lie on the autistic spectrum, (including my own son, who was diagnosed with both cerebral palsy and autism, which resulted from his brain injuries at birth). the answer has to be, yes!

If we regard autism as a destination, then there are many routes which lead to it. One such route which is currently a popular explanation for autism is the genetic route

In the case of autism, the probability that the brother or sister of a child with autism would also would be affected is between three and six percent. This number is modest enough so that the average general practitioner probably would never see enough cases of two affected siblings in the same family to suspect a genetic influence. However, this incidence is about 100 times greater than the rate at which autism affects unrelated people in the population. Another problem in detecting the genetic influence is that, unlike people who inherit say Huntington's disease, a genetic disease that does not strike until after the affected person has reached reproductive age, people affected with autism are so socially handicapped that mostly they never marry and have children. Consequently, researchers do not have the extended family histories that have played such a critical role in the identification of genes implicated in cystic fibrosis, breast cancer, and other diseases.
Twin studies, however, despite their inherent problems, have provided evidence for the role of genes in autism:
  • One study showed that the likelihood that the identical twin of an autistic child also would be autistic was 82 percent, whereas the equivalent rate for fraternal twins was only 10 percent.
  • With sophisticated statistical techniques and numerous twin studies, behavioral geneticists now believe that as much as 90 percent of the behavioral phenotype of autism is related to inherited genes.

However, despite this strong evidence of a genetic route to autism, we must be careful not to give the impression that the genetic explanation is the only one, because there are other factors which can cause autism!

If we consider autism as a 'destination,' a city if you like, then the causes become highways down which an individual can travel in order to arrive at the destination. The genetic highway is just one of them. In this case gene expression influences brain function and / or structure, so that the individual experiences what we know as autism. There are however many more 'highways' which influence brain function and / or structure. There is the highway called 'brain injury,' which itself can be acquired through a myriad of causes, such as oxygen starvation, drug abuse, infection, etc. There is a possibility that methylation provides another 'highway' where heavy metals such as mercury, actually stop the instructions which brain cells have 'written' into them to develop, and may actually kill cells.

So, when we consider autism, it is important to look past genetics and also consider other causes. So the answer to the question surely has to be an unequivocal 'yes,' - a head injury can cause autism?

Fortunately, due to the high degree of plasticity in the brain, - it's ability to create new synaptic connections and indeed to grow new cells, there is hope that if the correct developmental environment is provided, autistic children can improve in the areas where they face difficulties, - that is in the areas of communication, socialisation, imagination and sensory perception. This is the focus of our treatment regime at Snowdrop.

If you would like more information on autism, you can purchase our book by clicking here  or you can email us on snowdrop_cdc@btinternet.com.  Or you can visit our website at http://www,snowdropcerebralpalsyandautism.com

Tuesday, 14 September 2010

Ataxic Cerebral Palsy

What is ataxia?
Ataxia is caused by injury to a part of the brain called the 'cerebellum,' a structure low down in the back of the brain. The functions of the cerebellum are to help control balance and coordination via it's connection with the vestibular system and the eighth cranial nerve. It also has a function in regulation of muscle tone, smooth movement, proprioception and depth perception.
Injury to the cerebellum produces many symptoms such as poor balance, coordination, low muscle tone, (hypotonia),  jerky, uncontrolled movements, poor depth perception, wide based gait (walking or standing with the feet an unusual distance apart), poor proprioception, reading difficulties and a tremor which appears when the individual tries to move a limb.
These symptoms are seen in many conditions such as the cerebellar ataxia, cerebral palsy, multiple sclerosis and Friedreich's ataxia to name just a few.
The question is, can these problems be treated? The answer is 'yes, they can.' At Snowdrop we believe the answer to improvement of these difficulties lies in those important connections between the cerebellum and the vestibular system and consequently the pons, medulla and the eighth cranial nerve.
Let's take a look at where this neurological system begins, with the first order vestibular afferents (afferent nerves are nerves travelling into the brain from a sensory 'end system' in this case the ear). These nerves are bundled with others to become the Eighth cranial nerve. This nerve then enters the brainstem at the level between the pons and medulla, where the fourth ventricle is at its widest. A few of these vestibular nerves split off here and travel directly into the cerebellum through a part of that structure called the 'inferior cerebellar peduncle.
The eighth cranial nerve is actually three separate nerves in one bundle. One part is concerned with transmitting sensory information about hearing and the other two with sending sensory information about balance and proprioception from the middle ear to the cerebellum and brainstem. This is why, very often when we see a child who is suffering from injury to this system, we also see that the child is suffering a distortion of sensory processing with regards to their hearing. This distortion might result in the child experiencing oversensitive hearing, undersensitive hearing, or experiencing some other distortion to the perception of hearing.
At Snowdrop we have developed techniques to help ameliorate these symptoms and to help restart children's developmental processes. 
For more information about our methods visit http://www.snowdropcerebralpalsyandautism.com 

Saturday, 11 September 2010

Brain Plasticity in Action: - Function Determines Structure.

This study gives an excellent demonstration of the plasticity of the human brain and highlights that it is the environment to which we are exposed, which determines the structure of the brain. This has obvious treatment implications for children with brain injuries.

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London Cabbies Have Built In 'Sat-Nav'

Scientists say London taxi drivers have a built-in "sat-nav" system in their brains.

Magnetic scanners were used to explore the brain activity of taxi drivers as they navigated their way through a virtual simulation of London's streets, researchers said. Different brain regions were activated as they considered route options, spotted familiar landmarks or thought about their customers. The research was presented at last week's BA Science Festival.

Taxi drivers have a larger hippocampus - a region of the brain that plays an important role in navigation, according to previous studies. Researchers said their brains even "grow on the job" as they build up detailed information needed to find their way around London's labyrinth of streets - information famously referred to as "The Knowledge".

Dr. Hugo Spiers from University College London said they were keen to go beyond brain structure - and see what activity is going on inside the brains of taxi drivers while they are doing their job.  Functional magnetic resonance imaging (fMRI) was used to obtain "minute by minute" brain images from 20 taxi drivers as they delivered customers to destinations on "virtual jobs". The scientists adapted the Playstation2 game "Getaway" to bring the streets of London into the scanner.

The drivers were then shown a replay of their performance and reported what they had been thinking at each stage.
"We tried to peel out the common thoughts that taxi drivers tend to have as they drive through the city, and then tie them down to a particular time and place," said Spiers.

The scans showed a complex choreography of brain activity as the taxi drivers responded to different scenarios. The researchers said the hippocampus was only active when the taxi drivers initially planned their route, or if they had to completely change their destination during the course of the journey. Activity was noted in a different brain region when the drivers came across an unexpected situation - for example, a blocked-off junction. A separate part of the brain helped taxi drivers to track how close they were to the endpoint of their journey; like a metal detector, its activity increased when they were closer to their goal.  Changes were also noted in brain regions that are important in social behavior.

Spiers acknowledged that taxi driving is not just about navigation: "Drivers do obsess occasionally about what their customers are thinking," he said
Animals use a number of different mechanisms to navigate - the Sun's polarized light rays, the Earth's magnetic fields and the position of the stars.  He said this research provides new information about the specific roles of areas within the brains of expert human navigators.

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What this research does show is how the brain slowly builds the 'neural architecture' to enable individuals to function within the environment in which they find themselves.  This is the essence of brain plasticity and it is the essence of a Snowdrop programme of rehabilitation.  In the same way that exposure to driving London's streets, encourages plasticity within the brains of Taxi drivers, a Snowdrop programme, which exposes the child to demands for specific developmental functions, encourages and directs brain plasticity to build the neural architecture to support those developmental functions.

If you are interested in information about Snowdrop's treatment programmes for brain injury, email snowdrop_cdc@btinternet.com, or visit http://www.snowdropcerebralpalsyandautism.com

Monday, 6 September 2010

Early Language Development Linked to Whole Words.

This is why Snowdrop uses both 'top down' (whole word recognition techniques) and 'bottom up,'(phonological awareness programmes), in it's treatment of language and literacy development difficulties in children and adults who have problems with language development.
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Although babies typically start talking around 12 months of age, their brains actually begin processing certain aspects of language much earlier, so that by the time they start talking, babies actually already know hundreds of words. 

While studying language acquisition in infants can be a challenging endeavor, researchers have begun to make significant progress that changes previous views of what infants learn, according to a new report by University of Pennsylvania psychologist Daniel Swingley. The report, published in a recent issue of Current Directions in Psychological Science, a journal of the Association for Psychological Science, describes an increasing emphasis among researchers in studying vocabulary development in infants.

Infants have a unique ability to discriminate speech-sound (phonetic) differences, but over time they lose this skill for differentiating sounds in languages other than their native tongue. For example, 6 month old babies who were learning English were able to distinguish between similar-sounding Hindi consonants not found in English, but they lost this ability by 12 months of age. Since the 1980s it has been known that infants start focusing on their language's consonants and vowels, sometimes to the exclusion of non-native sounds. More recently, researchers have increasingly focused on how infants handle whole words.

Recent research has shown that during infancy, babies learn not only individual speech sounds but also the auditory forms of words; that is, babies are not only aware of the pieces that make up a word, but they are aware of the entire word. These auditory forms of words allow children to increase their vocabulary and help them to eventually develop grammar. Although they may not know what the words mean, children as early as 8 months start learning the phonological (sound) forms of words and are able to recognize them-and just being familiar with the words helps increase the children's vocabulary. Studies have shown that 18 month old children who are familiar with a word's form are better at learning what it means and are also able to differentiate it from similar sounding words.

Knowing word forms may also contribute to children's inferences about how their language works. For example, 7.5 month olds do not recognize words as being the same if they are spoken with different intonations or by a man and a woman. However, by 10.5 months of age, babies recognize the same words despite changes in the speaker or the intonation used. Another interesting finding was that although children learning a language can distinguish between long and short vowels, they interpret this difference according to the rules of their language. For instance, Dutch 18-month-olds considered tam and taam to be different words, while English 18-month-olds did not-showing children's early learning of how each language uses vowel length.

How can researchers find out what young children know about words and the forms of words with children have only just begun to talk? One method takes advantage of the fact that even young toddlers like to look at images or objects that we name. In these experiments, the children's eye movements are tracked while they are looking at two objects (for example, an apple and a dog). The researcher will say the name of one of the objects and see if the child's eyes move to that object. In this way, researchers can change the sound of the words slightly (for example, instead of "dog" say "tog") and see if the baby will look at the dog the same amount, as if indifferent to the change, or less, as is the case with adults who know that "dog" cannot be said as "tog." The results of those studies showed that the children were less likely to look at the correct object when it was mispronounced, indicating that by one year of age, children are able to recognize mispronunciations of words.

This new research in language acquisition indicates that infants learn the forms of many words and they begin to gather information about how these forms are used. The author notes that "these word forms then become the foundation of the early vocabulary, support children's learning of the language's phonological system, and contribute to the discovery of grammar."

In addition, there is a relationship between young children's performance in word recognition and their later language achievement. The author concludes that "testing very young children's ability to interpret spoken language, whether by identifying novel words as novel or by comprehending sentences, may prove a more sensitive predictor of children's language outcomes than simpler tests of speech-sound categorization."

If your child has language and communication difficulties and you are interested in treatment, visit Snowdrop's website at http://www.snowdropcerebralpalsyandautism.com or email us on snowdrop_cdc@btinternet.com

Thursday, 2 September 2010

Brain Damage in Autism not What Scientist Once Thought.

Reporting in the December 2000 issue of the Journal of Autism and Developmental Disorders, the Hopkins team said test results of parts of the cerebellum in 13 autistic children were the same as in normal children without autism.

The cerebellum has long been the focus of autism research because of the relentless responses autistic children make to sensory stimulation, according to Melissa Goldberg, Ph.D., assistant professor of child and adolescent psychiatry at the Johns Hopkins Children’s Center and the Kennedy Krieger Institute. “The stimulation we see autistic kids seeking out when they’re spinning or putting things in front of their eyes would seem to be linked to the part of the brain known to control such things as our ability to stabilize our bodies and what we see and touch,” she says. “But in this study we found this was not the case, at least not with the children with high-functioning autism.”

Cautioning that their findings may not apply to all autistic children, Goldberg and her team added that they “still don’t know what part of the brain is abnormal in autism.”

In their study, the Hopkins researchers examined the eye movements of 13 high-functioning autistic children ages 7 to 17, after spinning them in a chair as they sat upright, tilting their heads forward just after the chair became still. If the cerebellum is functioning normally, the reflexive eye movements, which typically occur in the direction opposite to that in which the child spins, are diminished once the head is pitched forward. Researchers found the autistic children’s eye reflexes diminished appropriately.

“This tells us that those parts of the cerebellum that govern our ability to restore balance operate normally in autistic children,” Goldberg says. “Knowing what parts of the brain do not appear damaged in these children, we can move on to investigate other sources of the problem.”

Dr. Goldberg and her colleagues plan to use brain imaging and other cognitive neuroscience research methods to investigate further how autistic brains operate and to corroborate their findings. In one study, for example, they are tracking infants at high risk of developing autism because they have a brother or sister with autism. The goal is to tease out genetic risk, and document the earliest indications of the onset of disorder, and to develop intervention strategies. This sibling study is led by colleague and co-author Rebecca Landa, Ph.D., an expert in child development and autism in the Division of Child and Adolescent Psychiatry at the Johns Hopkins Children’s Center and director of the Kennedy Krieger Center for Autism.
Autism is a developmental disorder that affects an estimated one in 500 children in the United States., according to the Centers for Disease Control (CDC). Children with autism have trouble making social connections or responding properly to sights, sounds and touch.

The study was funded by the National Alliance for Autism Research. The eye reflex portion of the study was conducted in the laboratory of co-investigator David Zee, M.D., professor of neurology, otolaryngology and ophthalmology at the Johns Hopkins Medical Institutions.
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I can understand them checking out the cerebellum, because so many children with autism do have difficulties with stabilisation and are obsessed with vestibular stimuli.  However, the cerebellum isn't the only structure which deal with this so why the particular focus here?  As for sensory stimuli and the ability to precess it appropriately, surely they know that the ascending reticular formation is heavily involved in determining what we pay attention to and the thalamus is heavily involved in the initial processing and re-routing of this information to the relevant parts of the cortex?  Do they not know this?  The primary part of a Snowdrop programme is focussed ensuring that these two parts of the brain are working as efficiently as possible, only then can we be sure that a child is perceiving the world in the way he should and only then will he react to the world in an appropriate manner.

Anyone interested in Snowdrop's work should contact me at snowdrop_cdc@btinternet.com or visit the website at http://www.snowdropcerebralpalsyandautism.com

Wednesday, 1 September 2010

Mealtime Interaction Patterns Between Children with Cerebral Palsy and their Mothers. - The Effects Upon Feeding and Language and Communication

This research supports the ideas in my book, 'Cerebral Palsy,' which was published last year. It is the early interaction patterns between carer and child, which are so vital for later language development, which are very often distorted when the child has cerebral palsy. This is why Snowdrop prescribes language and communication programmes designed to retrace these early interaction patterns.
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Background

A significant proportion of children with cerebral palsy have some degree of feeding impairment, which not only affects their ability to obtain adequate nourishment, but may also impinge on their ability to interact with their mothers during mealtimes. The quality of the maternal–child interaction may also be affected by the mealtime being prolonged and/or stressful. Patterns of interaction between mothers and their children with cerebral palsy have typically been described in play situations. There is limited information about interaction during mealtimes. The purpose of this study therefore, was to observe and describe the characteristics of mealtime interaction between mothers and their young children with cerebral palsy, and to determine whether feeding impairment and other sample characteristics were related to interaction patterns.

Methods

The participants were 20 mothers and their children with cerebral palsy. Physical, cognitive, and feeding abilities varied. Video recordings of each mother–child dyad interacting during a typical mealtime were analysed in order to describe the structure of the interaction, the communicative functions used, and what method the children used to communicate. The characteristics of the interaction were summarized and compared and the relationship between feeding ability and other child factors and interaction patterns were explored.

Results

Results revealed that interactions were maternally dominated. Mothers produced most of the communicative behaviour during the mealtime and used more directive functions than their children. The severity of feeding impairment was related to child patterns of interaction, but not to maternal interaction patterns. Language delay was also related to interaction patterns.

Conclusions

The results of this study highlight the importance for professionals to consider mealtime interactions for children with cerebral palsy and their mothers as an integral part of feeding investigations and ongoing interventions, as feeding impairment does seem to have a bearing on aspects of interaction.
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If you are interested in Snowdrop's treatment programmes for children with developmental problems, visit http://www.snowdropcerebralpalsyandautism.com