See: MEMORY, WEAK.
In retrograde amnesia, the loss of memory extends back for some time before the onset of the disorder.
In anterograde amnesia, there is an inability to store new information in the period following the onset of illness.
During registration, information from the sense organs and the cerebral cortex is put into codes for storage in the short-term memory system. The codes are usually acoustic (based on the sounds and words that would be used to describe the information) but may use any of the ?ve senses. This system can take only a few chunks of information at a time: for example, only about seven longish numbers can be retained and recalled at once – the next new number displaces an earlier one that is then forgotten. And if a subject is asked to describe a person just met, he or she will recall only seven or so facts about that person. This depends on attention span and can be improved by concentration and rehearsal – for example, by reciting the list of things that must be remembered.
Material needing storage for several minutes stays in the short-term memory. More valuable information goes to the long-term memory where it can be kept for any period from a few minutes to a lifetime. Storage is more reliable if the information is in meaningful codes – it is much easier to remember people’s names if their faces and personalities are memorable too. Using techniques such as mnemonics takes this into account.
The ?nal stage is retrieval. Recognising and recalling the required information involves searching the memory. In the short-term memory, this takes about 40-thousandths of a second per item – a rate that is surprisingly consistent, even in people with disorders such as SCHIZOPHRENIA.
Most kinds of forgetting or AMNESIA occur during retrieval. Benign forgetfulness is usually caused by interference from similar items because the required information was not clearly coded and well organised. Retrieval can be improved by recreating the context in which the information was registered. This is why the police reconstruct scenes of crimes, and why revision for exams is more e?ective if facts are learnt in the form of answers to mock questions.
Loss of memory or amnesia mainly affects long-term memory (information which is stored inde?nitely) rather than short-term memory which is measured in minutes. Short-term memory may, however, be affected by unconsciousness caused by trauma. Drivers involved in an accident may be unable to recall the event or the period leading up to it. The cause of amnesia is disease of or damage to the parts of the brain responsible for memory. Degenerative disorders such as ALZHEIMER’S DISEASE, brain tumours, infections (for example, ENCEPHALITIS), STROKE, SUBARACHNOID HAEMORRHAGE and alcoholism all cause memory loss. Some psychiatric illnesses feature loss of memory and AGEING is usually accompanied by some memory loss, although the age of onset and severity vary greatly.... memory
Symptoms. Sudden drawing-up of knees, nausea, vomiting, pallor, shallow breathing, prostration, weak heart beat, irritability, amnesia.
Treatment. Bed rest. Protection of eyes against light. Admission to hospital in case of deep brain damage. Quietness. Tranquillisers, sedatives and alcohol aggravate symptoms. If patient can swallow, alternatives as follows:–
Teas. St John’s Wort (concussion of the spine). Skullcap (to ease headache). Ginkgo (cerebral damage). Powders. Formula. Combine, St John’s Wort 3; Skullcap 2; Oats 2; Trace of Cayenne. Dose: 750mg (three 00 capsules or half a teaspoon) two-hourly.
Tinctures. Formula as above, but with few drops Tincture Capsicum in place of Cayenne powder: 1-2 teaspoons in water hourly.
Tincture Arnica. (European practise) 2-5 drops in hot water usually sufficient to hasten recovery.
Topical. Distilled Extract Witch Hazel saturated pad over eyes and to wipe forehead.
Supplements. Vitamin B-complex. B6, C. ... concussion
Alcohol depresses the central nervous system and disturbs both mental and physical functioning. Even small doses of alcohol will slow a person’s re?exes and concentration; potentially dangerous effects when, for example, driving or operating machinery. Drunkenness causes slurred speech, muddled thinking, amnesia (memory loss), drowsiness, erectile IMPOTENCE, poor coordination and dulled reactions – thereby making driving or operating machinery especially dangerous. Disinhibition may lead to extreme euphoria, irritability, misery or aggression, depending on the underlying mood at the start of drinking. Severe intoxication may lead to COMA and respiratory failure.
Persistent alcohol misuse leads to physical, mental, social and occupational problems, as well as to a risk of DEPENDENCE (see also ALCOHOL DEPENDENCE). Misuse may follow several patterns: regular but controlled heavy intake, ‘binge’ drinking, and dependence (alcoholism). The ?rst pattern usually leads to mainly physical problems such as gastritis, peptic ulcer, liver disease, heart disease and impotence. The second is most common among young men and usually leads to mainly social and occupational problems – getting into ?ghts, jeopardising personal relationships, overspending on alcohol at weekends, and missing days o? work because of hangovers. The third pattern – alcohol dependence – is the most serious, and can severely disrupt health and social stability.
Many researchers consider alcohol dependence to be an illness that runs in families, with a genetic component which is probably passed on as a vulnerable personality. But it is hard to disentangle genetic, environmental and social factors in such families. In the UK there are estimated to be around a million people suffering from alcohol dependence and a similar number who have di?culty controlling their consumption (together about 1:30 of the population).
Alcohol causes tolerance and both physical and psychological dependence (see DEPENDENCE for de?nitions). Dependent drinkers classically drink early in the morning to relieve overnight withdrawal symptoms. These symptoms include anxiety, restlessness, nausea and vomiting, and tremor. Sudden withdrawal from regular heavy drinking can lead to life-threatening delirium tremens (DTs), with severe tremor, hallucinations (often visual – seeing spiders and monsters, rather than the pink elephants of romantic myth), and CONVULSIONS. This must be treated urgently with sedative drugs, preferably by intravenous drip. Similar symptoms, plus severe INCOORDINATION and double-vision, can occur in WERNICKE’S ENCEPHALOPATHY, a serious neurological condition due to lack of the B vitamin thiamine (whose absorption from the stomach is markedly reduced by alcohol). If not treated urgently with injections of thiamine and other vitamins, this can lead to an irreversible form of brain damage called Korsako?’s psychosis, with severe amnesia. Finally, prolonged alcohol misuse can cause a form of dementia.
In addition to these severe neurological disorders, the wide range of life-threatening problems caused by heavy drinking includes HEPATITIS, liver CIRRHOSIS, pancreatitis (see PANCREAS, DISEASES OF), gastrointestinal haemorrhage, suicide and FETAL ALCOHOL SYNDROME; pregnant women should not drink alcohol as this syndrome may occur with more than a glass of wine or half-pint of beer a day. The social effects of alcohol misuse – such as marital breakdown, family violence and severe debt – can be equally devastating.
Treatment of alcohol-related problems is only moderately successful. First, many of the physical problems are treated in the short term by doctors who fail to spot, or never ask about, heavy drinking. Second, attempts at treating alcohol dependence by detoxi?cation or ‘drying out’ (substituting a tranquillising drug for alcohol and withdrawing it gradually over about a week) are not always followed-up by adequate support at home, so that drinking starts again. Home support by community alcohol teams comprising doctors, nurses, social workers and, when appropriate, probation o?cers is a recent development that may have better results. Many drinkers ?nd the voluntary organisation Alcoholics Anonymous (AA) and its related groups for relatives (Al-Anon) and teenagers (Alateen) helpful because total abstinence from alcohol is encouraged by intensive psychological and social support from fellow ex-drinkers.
Useful contacts are: Alcoholics Anonymous; Al-Anon Family Groups UK and Eire (including Alateen); Alcohol Concern; Alcohol Focus Scotland; and Alcohol and Substance Misuse.
1 standard drink =1 unit
=••• pint of beer
=1 measure of spirits
=1 glass of sherry or vermouth
=1 glass of wine
Limits within which alcohol is believed not to cause long-term health risks:... alcohol
Alternatives: to improve concentration.
Teas, Liquid extracts, tinctures or powders: Ginseng, Gotu Kola, Hawthorn (berries or blossoms), Holy Thistle, Horsetail, Kola nuts, Periwinkle (minor), Rosemary, Skullcap, Vervain, Ginkgo.
Ginkgo: impressive results reported.
Practitioner. Ephedra.
Supplements. B-complex, B6, B12, E. Phosphorus, Zinc. ... memory, weak
Types of dissociative disorder include hysterical amnesia (see hysteria), fugue, depersonalization, and multiple personality.
(See also conversion disorder.)... dissociative disorders
Benzodiazepines act at a speci?c centralnervous-system receptor or by potentiating the action of inhibitory neuro-transmitters. They have advantages over other sedatives by having some selectivity for anxiety rather than general sedation. They are safer in overdose. Unfortunately they may cause aggression, amnesia, excessive sedation, or confusion in the elderly. Those with long half-lives or with metabolites having long half-lives may produce a hangover e?ect, and DEPENDENCE on these is now well recognised, so they should not be prescribed for more than a few weeks. Commonly used benzodiazepines include nitrazepam, ?unitrazepam (a controlled drug), loprazolam, temazepam (a controlled drug) and chlormethiazole, normally con?ned to the elderly. All benzodiazepines should be used sparingly because of the risk of dependence.... benzodiazepines
Before treatment, the patient will have been fasted for at least eight hours. After checking for any potential drug ALLERGY or interactions, the patient is given a general anaesthetic and muscle relaxants. Depending on the side of the patient’s dominance, either unilateral (on the side of the non-dominant hemisphere of the BRAIN) or bilateral (if dominance is uncertain,
e.g. in left-handed people) positioning of electrodes is used. Unilateral ECT has the advantage of being associated with less anterograde AMNESIA. When the current passes, the muscles will contract for approximately 10 seconds, with further tonic spasms lasting up to a minute. The patient should then be put in the COMA or recovery position and observed until fully conscious. Up to 12 treatments may be given over a month, improvement usually showing after the third session. Widely used at one time, the treatment is now given only rarely. It can be extremely frightening for patients and relatives and is not recommended for children.... electroconvulsive therapy (ect)
When the fugue ends, the person has no recollection of what has occurred.
Fugues are uncommon, and causes include dissociative disorders, temporal lobe epilepsy, depression, head injury, and dementia.
(See also amnesia.)... fugue
Habitat: South India, Assam and Bengal.
Ayurvedic: Aakshiki (non-classical).Siddha/Tamil: Puvatti, Shempuvan.Folk: Aashaphala (Bengal), Naag- lichi (Assam).Action: The aril of the fruit is used in prescriptions of Chinese traditional medicine for treating insomnia, neurosis, palpitation, amnesia and anaemia.
It has been found to ameliorate the impaired learning process in mice.An aqueous extract of the fruit pulp showed stimulating effect on superoxide dimutase activity in red blood cells of mice., indicating its possible use in delaying the aging process.The seeds contain antimutagens, amino-hydroxy-hexynoic acid, hypo- glycin A (which causes hypoglycaemia) and amino-hydroxy-heptynoic acid.... euphoria longanThe name originates from the ancient idea that hysteria – a Greek-based word for ‘UTERUS’
– was in some way associated with the womb. Hence the old-fashioned association of hysteria with women, and with supposed sexual disturbances. Doctors should make sure there is not a physical disease present to explain the symptoms before diagnosing a dissociative disorder. Most subside spontaneously, but if not, the individual needs psychiatric advice. Treatment is di?cult. Reasons for stress should be explored and, if possible, resolved. Hypnosis (see HYPNOTISM) to help the person to relive stressful episodes – known as ABREACTION – may be of value.... hysteria
If the head injury is mild, there may only be a slight headache. In some cases there is concussion. More severe head injuries may result in unconsciousness or coma, which may be fatal. Amnesia may occur. After a severe brain injury, there may be some muscular weakness or paralysis and loss of sensation. Symptoms such as persistent vomiting, double vision, or a deteriorating level of consciousness could suggest progressive brain damage.
Investigations may include skull X-rays and CT scanning. A blood clot inside the skull may be life-threatening and requires surgical removal; severe skull fractures may also require surgery. Recovery from concussion may take several days. There may be permanent physical or mental disability if the brain has been damaged. Recovery from a major head injury can be very slow, but there may be signs of progressive improvement for several years after the injury occurred.... head injury
The brain and spinal cord form the central nervous system (CNS), which consists of billions of interconnected neurons (nerve cells). Input of information to the CNS comes from the sense organs. Motor instructions are sent out to skeletal muscles, the muscles controlling speech, internal organs and glands, and the sweat glands in the skin. This information is carried along nerves that fan out from the CNS to the entire body. Each nerve is a bundle consisting of the axons (filamentous projections) of many individual neurons.
In addition to the nervous system’s anatomical divisions, there are various functional divisions. Two of the most important are the autonomic nervous system, concerned with the automatic (unconscious) regulation of internal body functioning, and the somatic nervous system, which controls the muscles responsible for voluntary movement.
The overall function of the nervous system is to gather and analyse information about the external environment and the body’s internal state, and to initiate appropriate responses, such as avoiding physical danger.
The nervous system functions largely through automatic responses to stimuli (see reflex), although voluntary actions can also be initiated through the activity of higher, conscious areas of the brain.
Disorders of the nervous system may result from damage to or dysfunction of its component parts (see brain; spinal cord; neuropathy; nerve injury). They may also be due to impairment of sensory, analytical, or memory functions (see vision, disorders of; deafness; numbness; anosmia; agnosia; amnesia), or of motor functions (see aphasia; dysarthria; ataxia). ... nervous system
Korsakoff’s psychosis may follow Wernicke’s encephalopathy if treatment is not begun promptly enough. Symptoms consist of severe amnesia, apathy, and disorientation. Korsakoff’s psychosis is usually irreversible.... wernicke–korsakoff syndrome
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