Ataxia is a lack of co-ordination in the muscles. It is a symptom of damage to part of the central nervous system. Locomotor ataxia involves a lack of balance, or equilibrium. Patients must stand on a broad base, eyes open, or they will sway or even fall. The swaying increases if they shut their eyes. Ataxia has many causes, locomotor ataxia may be due to syphilis for example. Many diseases that damage the central nervous system may cause ataxia, including tumours of the cerebrum or cerebellum, some deficiency diseases, and diseases of the spinal cord. Ataxia may also result from overuse of such drugs as barbiturates or alcohol. Research Ataxia
The autonomic nervous system is responsible for the self-controlling aspects of the body's nervous network, and is under the control of the cerebral cortex, the hypothalmus, and the medulla oblongata. Working in tandem with the central nervous system, the autonomic nervous system features two subsystems which regulate body functions such as involuntary smooth muscle movement and heart rate. These two subsystems are called the sympathetic and parasympathetic nervous system, and their functions operate in opposition to one another, delicately balancing the bodily functions which they control. The sympathetic nervous causes fight or flight responses in moments of stress or stimulus, such as increased heart rate, saliva flow, and perspiration. The parasympathetic system counterbalances these effects by slowing the heart rate, dilating blood vessels, and relaxing involuntary smooth muscle fibres. Viewed individually, the sympathetic nervous system, also referred to as the thoracolumbar system, features a series of nerves which branch out of the spinal cord between the first thoracic vertebra and the second lumbar vertebra. These nerve fibres join into a long trunk of fibres, called the sympathetic trunk, on each side of the spinal cord. Along the sympathetic trunk are enlarged clusters of nerve fibres, called ganglia.
From these ganglia, a number of nerve fibres extend throughout the body's tissues. Many of these nerves create additional ganglia, such as the celiac ganglia and the mesenteric ganglia. The sympathetic nerves are responsible for contracting involuntary smooth muscle fibres, viscera, and blood vessels, speeding up the heart rate, and dilating the bronchial tubes in moments of stress. The parasympathetic nervous system, also referred to as the craniosacral system, features ganglia in the midbrain, in the medulla oblongata, and in the sacral region. The first two, the cranial ganglia of the parasympathetic system, give pass impulses to the facial, oculomotor, glossopharyngeal, and vagus nerves. The sacral group of parasympathetic nerves originate at the second, third, and fourth vertebrae and extend nerves to the bladder, the distalcolon, the rectum, and the genitals. The nerves of the parasympathetic nervous system are responsible for conserving and restoring energy in the body following a sympathetic response to stress. Research Autonomic Nervous System
Benzodiazepines are sedative-hypnotic drugs that are structurally similar and include widely used drugs such as chlordiazepoxide, diazepam, and oxazepam. The different
benzodiazepines are absorbed at different rates, and the timing of their psychoactive effects varies with the absorption rate. Benzodiazepines are usually taken orally and are metabolised in the liver. Some benzodiazepine metabolites are pharmacologically active.
Benzodiazepines potentiate the effect of other central nervous system depressants, such as ethylalcohol. Research Benzodiazepines
The brain is the primary component of the nervous system, occupying the cranial cavity. Without its outermost protective membrane, the dura mater, the brain weighs an average of 1.4 kilograms, comprising about 97% of the entirecentral nervous system. The brain is connected to the upper end of the spinal cord (which connects through the foramen magnum of the skull) and is responsible for issuing nerve impulses, processing nerve impulse data, and engaging in the higher order thought processes. The brain is divided into three parts: the large cerebrum, the smaller cerebellum, and the brainstem leading to the spinal cord. The brainstem is also descriptively divided into the medulla oblongata, the midbrain, and the pons. The right hemisphere of the brain is a part of the cerebrum. The cerebrum, or forebrain, forms the bulk of the brain, formed of a large mass of white and grey neural fiber in the upper cranium. It is responsible for the higher thought processes (memory, judgement, reason), processing sensory data, and with initiating willful motor processes, such as voluntary muscle flexion. The cerebrum is composed of two lateral halves, or hemispheres, which feature a number of folds (gyri) and furrows (sulci) and which are connected in the middle at the medulla. Containing about a trillion neurons, the human brain is the most complex mechanism known, and its many functions are still largely a mystery. Research Brain
The brain stem operates automatically to control vital body functions such as breathing and blood pressure. It is a eight centimeter long stalk of nerve cells and fibres that joins the upper part of the spinal cord with the brain. The medulla oblongata is the lowest part of the brain stem and serves as the site of connection between the brain and the spinal cord. The pons is located in the brainstem, vertically between the midbrain and the medulla oblongata, and sagittally between the cerebellum and the pituitary gland. It is responsible for serving as a bridge between the cerebrum, the cerebellum, and the medulla oblongata. The brain stem is an extension of the spinal cord and acts as a highway for messages traveling from other parts of the brain to the spinal cord. The spinal cord and the brain form the central nervous system (CNS), which controls all of the body's basic functions such as breathing, the rate of your heart beat, and body temperature. Research Brain Stem
Chlorpromazine hydrochloride (Thorazine, largactil) is a depressive drug which is orally ingested or injected. It has undetermined psychotropic effects on the Central nervous system and is used in the management of manic psychotic disorders and disturbances, and also post-operative vomiting. It is also used to produce a state of artificial hibernation for operations on the heart and great vessels. Research Chlorpromazine Hydrochloride
The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
Abbreviations
Research Phylum Chordata
