Sunday, 27 September 2009

Injury to the Midbrain.

The midbrain is a small structure, which lies just above the Pons at the top of the brainstem. It is comprised of smaller structures called the tectum, the tegmentum' the substantia nigra, and the cerebral penduncles. It contains an important group of cells called the 'red nucleus.' At its top end it is connected to the Thalamus and hypothalamus.

Sensory information is processed by the midbrain on it's way to higher centres such as the thalamus. So the midbrain plays it's part in sensory functions such as in helping to control eye movement, depth perception, in addition to other visual and auditory system functions. The red nucleus and substantia nigra help to control body movement and the substantia nigra produce a neurotransmitter called 'dopamine.' Dopamine is part of the 'reward' system of the brain and is involved in motivation and the formation of the addictive process.

When the midbrain is injured, we see several effects.
  • Loss of pupillary reaction
  • Abnormally shaped pupils.
  • Resting tremor (due to injury to dopamine producing cells)
  • Extreme rigidity, (as opposed to spasticity)
  • Auditory disturbances
  • Parkinson's disease
  • Athetosis
  • Coma (if there is injury to the tegmentum).
Parkinson's disease is produced by degeneration in dopamine producing neurons, whilst athetoid cerebral palsy is caused by injury to the same neurons.

Can the injured Midbrain be treated?

Yes! Like all other areas of the brain the mibrain adapts it's functioning and structure to accommodate the environment in which the individual finds himself. If we can provide the correct developmental environment, this inherent plasticity can be harnessed and the individual's probems may improve. If you would like more information about Snowdrop's treatment programmes for brain injury, visit http://www.snowdrop.cc

Monday, 21 September 2009

Injury to the brain. - Absence of the Septum Pellucidum.

What is Absence of the Septum Pellucidum?

Absence of the septum pellucidum (ASP) is a rare disorder, (occuring in an estimated 2 to 3 individuals per 1 00,000 people in the general population). It is characterised by abnormal development of a thin membrane located at the midline of the brain. It runs down from the corpus callosum, the structure which connects the two cerebral hemispheres of the brain and effectively acts as a separator for the two hemispheres. The disorder usually occurs with other neurological abnormalities such as agenesis / dysgenesis of the corpus callosum.

Individuals with ASP may experience vision impairment or blindness. They may also have coordination problems and hormone deficiencies that result in short stature. Intelligence is usually affected and learning disabilities are common. The disorder usually manifests early in life, often as a consequence of discovering the other neurological abnormalities, such as corpus callosum abnormalities or septo – optic dysplasia. Symptoms include involuntary eye movements, a wasting of a part or parts of the body, and short stature. Seizures and inappropriate behaviour, such as displays of 'sham rage' may also occur. The cause of ASP is currently unknown.

What is the prognosis?

The prognosis of ASP varies depending on the severity of co-occurring abnormalities. Many cranial abnormalities are life threatening, but alone ASP is not a life-threatening disorder.

Can ASP be treated?

When a part of the brain is actually missing, - having not developed at all, then obviously no amount of treatment is going to be able to restore that missing neurology. What we can strive to do is to enable the neurology which is present to function at maximum efficiency and therefore give the child the opportunity to achieve his / her maximum potential. We believe that that at Snowdrop, we teach parents how to provide an appropriately stimulating developmental environment for this to happen. To learn more about Snowdrop programmes of developmental stimulation visit our website.

Wednesday, 9 September 2009

Successes


All of the children below are following a Snowdrop rehabilitation programme and have made the following progress since their last reassessment.

  • 1 Child who was not expected to walk, progressed to walking.
  • 1 Child who had no mobility progressed to commando crawling.
  • 2 children progressed from having no spoken language to talking.
  • 2children who did not make eye - contact due to visual oversenitivity, have begun to do so.
  • 1 child who used a self stimulatory 'hand flapping' around his eyes due to visual undersensitivity has stopped needing to do this.
  • 1 Child who could not tolerate the noise of a classroom environment has begun to do so.
  • 2 Children who could not read, began to do so.
  • 2 Children who were almost completely unable to see, began to use their vision in a functional manner
  • 2 Children who were oversensitive in tactile terms began to tolerate and appreciate pleasant tactile sensations.
  • 1 Child who had profound problems with circadian rhythm, causing a chaotic sleeping pattern, began to sleep more regularly
  • 1 Child who produced no sound, began to produce a range of noises.
  • 1 Child who held his hands in a constant grasp reflex, began to open them.
  • 1 Child whose suffered tactile undersensitivity in the arms and hands which was so severe he was not aware he possessed hands, began to use his hands functionally.
  • A reduction of seizures was reported in 2 children
  • 1 Child called his Mama's name for the first time.

Congratulations to the parents and helpers who worked so hard to bring about these changes in their children. You constantly amaze me.

Tuesday, 8 September 2009

Visual Overload and Visual Crowding - When More Means Less

A really interesting post from 'Eide Neurolearning Blog' which supports what I and others before me, such as Carl Delacato have been saying about some of the brain injured children we see for many years. Some of our kids experience 'sensory overload,' which is just one of many possible distortions of sensory processing. This particular article is concerned with vision and alludes to children with dyslexia, but believe me Kids experience these types of problems in every sensory modality. The evidence points to it being a malfunction in the thalamic reticular formation, which is responsible for 'exciting' the relevant part of sensory cortex in order that it may adequately process the sensory information being passed to it. In some cases, it over - excites the cortical region, resulting in the type of sensory overload described here. These neural structures can be re-tuned so that they excite the cortex appropriately, which is precisely what some of Snowdrop's programmes are designed to do.

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"If there were only 10 problems on a page, I could do them all. But when there are 40 on a page, I can't do any of them." - 10 year old student


Visual overload and visual crowding are common problems in every school classroom or company work group, but the mistakes and errors that result from them are rarely recognized or traced back to their true source. It is a paradox - the more you see, the less you see, but it all makes sense if one recognizes that a child or an adult's visual working memory deskspace can become easily overloaded.

For visual scientists, visual crowding is a specific term that refers to a greater difficulty in seeing when other visual objects are present. When we look at a complex scene, for instance the picture above, it is impossible to take in all the other visual details. It's what causes some people to overload when they go to large gatherings like music concerts, Disneyland in the summertime, or a crowded Home Depot, but also children in crowded classroom, all-school assembly, writing on a scantron, or completing Mad Math Minutes.

Signs of Visual Overload
- Longer processing time, slow reading, and incomplete work on crowded worksheets
- Tantrums, irritability, and overload behaviors in crowded environments
- 'Careless' mistakes and unintentionally skipped problems on worksheets and tests
- Missed words or endings while reading, need to re-read words

Interestingly, a recent report on Visual crowding, reading, and dyslexia found that a visual crowding effect significantly contributed to slowness in word reading, and dyslexics as a group found that increased spacing between letters improved readability. The critical spacing threshold for readability was significantly higher for dyslexics as a group compared to non-dyslexic controls, so it became easier to identify a letter away from the center if the spacing between characters were greater.

Take-home points:

- Critical print size is larger for dyslexics than controls
- Critical spacing between characters is larger for dyslexics than controls
- Reading rate improves with print size to a critical point
- Explains why many dyslexics with excellent verbal funds of knowledge still have trouble reading long words

Classroom and Test Accommodations

In the classroom, more attention should be paid to print size and spacing in daily classroom (worksheets, handouts) and testing materials (as many as 1 in 5 students are dyslexic), and print size and spacing should be considered when purchasing books for students.

Large print books and reader glasses may help some students, whereas font differences (serifs like Times New Roman or hand-written fonts like Papyrus or Comic Sans often preferred) may be more important for others. For students with narrow visual spans (see only few letters at a time), serifs or handwritten fonts may dramatically lessen the work of reading - with serifs or personalized font shapes - it is easier to perceive the overall shape of words, so that even if a reader only sees the first and last letters and general shape of the word, they can make an educated guess about what that word might be even though they are unable to see all the letters.

Many of you are probably aware of this meme from the Internet:

"Aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt tihng is taht the frist and lsat ltteer be at the rghit pclae. The rset can be a toatl mses and you can sitll raed it wouthit porbelm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe."

Matt Davis has written more about the science and history of the discovery of this effect here.

Thursday, 3 September 2009

Gel hope for brain - injury repair.

This article by the BBC looks to be a significant step forward and is very exciting. There is a long way to go and I am sure that programmes of developmental stimulation such as those provided by Snowdrop will always have a place, but this looks really promising.