Canadian Journal of Neurological Sciences

Although fatigue is recognized as a symptom of MS, there have been insufficient methods for evaluating this symptom. We administered the Fatigue Impact Scale to 85 MS patients and 20 hypertensive patients. Neurologic impairment, mental health, and general health status were also assessed. MS patients reported significantly higher fatigue impact than hypertensive patients. Most MS patients reported fatigue as either their worst (14%), or one of their worst (55%) symptoms. Disease classification and neurologic impairment had little bearing on Fatigue Impact Scale scores in the MS sample. The best predictive models for mental health and general health status in the MS sample both included the Fatigue Impact Scale as a significant factor. This study demonstrates that: 1) fatigue is a very prevalent and severe problem in MS, 2) fatigue impact cannot be predicted by clinical measures of neurologic impairment, 3) fatigue has a significant effect on the mental health and general health status of MS patients.

3-Nitropropionic acid (3-NPA) — a suicide inhibitor of succinate dehydrogenase — is a widely distributed plant and fungal neurotoxin known to induce damage to basal ganglia, hippocampus, spinal tracts and peripheral nerves in animals. Recent reports from Northern China indicate that 3-NPA is also likely to be responsible for the development of putaminal necrosis with delayed dystonia in children after ingestion of mildewed sugar cane. This article discusses the role of 3-NPA in the causation of the disease in China, its neurotoxic effects in animals and the potential role for this compound as a probe of selective neuronal vulnerability.

The serious, late complication of superficial cerebral hemosiderosis, which appears after several years in 1/4–1/3 of patients who have undergone hemispherectomy, has resulted in recent years in a considerable reluctance to carry out this operation despite the fact it has proved to be highly effective in patients with medically refractory seizures associated with hemiplegia. Preservation of a small portion of the hemisphere, usually the frontal or occipital pole, has proved to be effective in preventing this late complication, but at the cost of a significant reduction in the effectiveness of the operation in reducing the patients’ seizure tendency. Preserving the frontal and occipital poles but disconnecting them from the rest of the brain, resulting in a functional complete but anatomical subtotal hemispherectomy, retains the therapeutic effectiveness of a complete hemispherectomy while still protecting adequately against the serious late postoperative complication of superficial cerebral hemosiderosis and its associated neurologic deterioration, hydrocephalus and sometimes death.

The kindling effect is a relatively permanent alteration in brain function which results from repeated electrical or chemical stimulation and culminates in the appearance of electrographic and behavioral convulsions whenever the original stimulus is reapplied. The effect results from tetanic activation in the anterior cortex, limbic system or associated areas of the adult mammalian brain, and the lasting alterations are transynaptic and quite widespread. They are based in part on synaptic facilitation, and they are accompanied by specific alterations in normal behavior. In these and other respects, kindling is analogous to normal learning. It is possible that the stored component (engram) of kindling involves the same physiological mechanism as the engram of normal long term memory. Morphological study of identified synapses has not provided conclusive evidence for an anatomical substrate of kindling, but physiological experiments demonstrate a lasting potentiation of the excitatory postsynaptic potential.

Motor evoked potentials (MEPs) were recorded from selected non-wasted, non-denervated hand muscles in 40 patients with Amyotrophic Lateral Sclerosis (ALS) with both upper and lower motor neuron signs. In most the compound muscle action potential (CMAP) of the target muscle was normal. Compared to the control group, cortical threshold in ALS varied considerably and there was a significant (r²= 0.702) inverse, exponential, correlation between cortical threshold and MEP/CMAP ratio. There was a linear correlation between threshold and disease duration (r²= 0.66) so that early in the disease threshold was normal and later the motor cortex could not be stimulated. It is suggested that early in ALS normal threshold reflects glutamate-induced hyper-excitability of the corticomotoneuron. The findings lend support to the hypothesis that ALS is primarily a disease of the corticomotoneuron.

Many diseases with an auto-immune etiology have a skewed sex distribution. In the majority of instances, women are affected more frequently than men. A review of population studies demonstrates that the preponderance of women in multiple sclerosis (MS) is almost constant. We show that this preponderance is further increased in early as well as in late-onset cases, in familial cases as well as in MS twin pairs and that the HLA-DR2 allele, which has been associated with MS in Caucasian populations, is significantly more frequent in women than in men with MS. “Rules” have been established for multifactorial diseases; MS contravenes most of those rules. The skewed sex distribution in MS could be attributed to the known hormonal and gender influences on the immune response, as well as to genetic influences.

Parkinsonism (P) with progressive dementia (D) of the Alzheimer type is recognized as a clinical variant of a form of amyotrophic lateral sclerosis (ALS) that has occurred in high incidence among the Chamorro people of the islands of Guam and Rota in the Marianas chain of Micronesia. The declining annual incidence, upward shifting of the age of onset, narrowing of the sex ratio, and occurrence of the disease among non-Chamorros, point to a disappearing environmental causation peculiar to the traditional culture of these islands. Evidence is presented in support of the proposal that heavy use of certain toxic plants, notably cycads, a traditional source of food and medicine for the Chamorro people, plays an important etiological role. Clinical and epidemiological approaches are offered to test for a relationship between ALS/P-D and long-latency plant toxicity.

Epilepsy directly affects 50 million people worldwide.Most can achieve excellent seizure control; however, people living with epilepsy continue to suffer from enacted or perceived stigma that is based on myths, misconceptions and misunderstandings that have persisted for thousands of years. This paper reviews the frequency and nature of stigma toward epilepsy. Significant negative attitudes prevail in the adolescent and adult public worldwide leading to loneliness and social avoidance both in school and in the workplace. People with epilepsy are often wrongly viewed as having mental health and antisocial issues and as being potentially violent toward others. Twenty-five percent of adults having epilepsy describe social stigma as a result of their epilepsy. They fear rejection and often feel shame or loneliness from this diagnosis. The psychosocial and social impact of epilepsy is significant. Yet few specific interventions have been demonstrated to alter this perception. The effect on public education is primarily short-term, while change over the long-term in attitudes and inaccurate beliefs have not presently been proven effective. School education programming demonstrates improved knowledge and attitude a month after a classroom intervention, but persisting change over a longer period of time has not been evaluated. In-depth adult psycho-educational programs for adults with epilepsy improves knowledge, coping skills and level of felt stigma. However these gains have not demonstrated persistence over time. Myths, misconceptions and misunderstandings about epilepsy continue and programs aimed at increasing knowledge and reducing negative public attitudes should be enhanced.