Common symptoms of advanced multiple sclerosis are urinary incontinence, visual disturbances, muscular weaknesses, numbness, tremor and loss of motor co-ordination (ataxia).
There is evidence to prove that multiple sclerosis is far greater in people who spent their childhoods in cooler climates even if they subsequently moved to a warmer climate. In terms of genetics it appears to be rare amongst Gypsies and Asians even when they live in environments, which the incidence of disease is high in other groups. There is currently no cure for multiple sclerosis.
- A tumour destroys the fusiform gyrus in your right temporal lobe
The result of a tumour destroying the fusiform gyrus in a persons right temporal lobe is a disease called Autism. Autism is a lifelong developmental disorder characterised by social interactions and language, and a narrow range of interests and activities. Children that suffer from this may or may not appear on the surface to be mentally deficient, but they tend to perseverate (e.g. continually nodding head or making stereotyped finger movements.) and they seem to have immense difficulty understanding and judging other people’s thoughts or feelings.
It is a tragic disease that can isolate a child sufferer from not only the world around he or she but also more importantly means he or she withdraws from family interaction due to loss of language skills. The disorder is found in about one to two children per thousand and is much more common in males than in females and is strongly inheritable. There is no cure, but many children with autism are helped a great deal by highly structured training in language and behaviour.
- The cells in the substantia nigra degenerate
Degeneration of the nerve cells located in the brainstem also known as the substantia nigra, causes Parkinson’s disease. The substantia nigra is the midbrain nucleus whose neurons project via the nigrostriatal pathway to the striatum of the basal ganglia.
Parkinson’s disease is a movement disorder of middle and old age that affects about 0.5% of the population. Its initial symptoms are mild to begin with, no more than a slight stiffness or tremor of the fingers but they inevitably increase in severity with advancing years. The disease was first noted by James Parkinson, 200 years ago who noticed people in London who moved quite slowly and showed regular tremors of the hands and face while at rest, and walked stiffly. There is also a loss of facial muscle ton giving the sufferer a mask like appearance.
Full-blown symptoms emphasise this tremor that is pronounced during inactivity but not during voluntary movement or sleep and also muscular rigidity, difficulty initiating movements and slowness of movement. There is typically little or no intellectual impairment, thus the sufferers are normal people stuck in a body they cannot control. In short sufferers have great difficulty in all motor efforts, no matter how routine.
It is the dopamine containing cells in the substantia nigra that projects to the striatum. The loss of cells in this area is continuous but symptoms only appear after a major loss. The symptoms of Parkinson’s disease can be alleviated by injections of L-DOPA, the chemical from which dopamine is synthasised. The purpose of the L-DOPA is to enhance dopamine levels of surviving cells. Although L-DOPA does reduce symptoms in sufferers of Parkinson’s disease in terms of a decrease in tremors and an increase in speed of movement, it is only a temporary improvement and not a permanent solution. This is due to the fact that eventually too few dopamine containing neurons remain in the substantia nigra, to be influenced by the intake of L-DOPA. Also nerve cell degeneration in the substantia nigra is unstoppable and thus continuous.
At present there is no cure for Parkinson’s disease but in the last few years several important findings have been reported. One in particular was a discovery of a gene mutation associated with a rare form of Parkinson’s disease in four different families. This rare form has an early age of onset and runs in families. Although this same gene mutation is unlikely to be a causal factor in the vast majority of Parkinson’s cases, it does provide one of many important clues about the nature of the changes that underlie this disorder.
- Your mamillary bodies cease to function
Damage of the mamillary bodies of the hypothalamus is responsible for the memory deficits of Korsakoff patients. Korsakoff’s syndrome is a disorder of memory that is common in people who consume large amounts of alcohol. Thus heavy drinking could lead to the mamillary bodies ceasing to function and thus the person suffering from Korsakoff’s syndrome. In its advanced stages it is characterized by a variety of sensory and motor problems, extreme confusion, personality changes, and a risk of death from liver, gastrointestinal, or heart disorders. Korsakoff syndrome sufferers fail to recall many items or events of the past. If such an event is recalled or repeated again the patient does not feel any sort of link or familiarity towards it. These patients often fail to realise anything is wrong with them at all and may fill a gap in their memory with a fabrication that they seem to accept to be true.
Mair et al. (1979) examined two Korsakoff’s patients for several years, using a battery of behavioural tests, later when they examined the brains of these patients in detail they found that both showed shrunken, diseased mammillary bodies.
Bibliography
- Biological Psychology - Rosenzweig
- Biopsychology – John .J. Pinel
- Principles of Biopsychology – Simon Green
