A disturbance in the ability to select the words with which to speak and write and/or to understand speech or writing. It is caused by damage to speech and comprehension regions of the brain. (See also aphasia.)
Dysphasia may come on suddenly and last only for a few hours or days, being due to a temporary block in the circulation of blood to the brain. The effects may be permanent, but although the individual may have di?culty in understanding language and expressing themselves, they will be quite aware of their surroundings and may be very frustrated by their inability to communicate with others.
Further information may be obtained from Speakability.
Delirium (confusion) In some old people, acute confusion is a common e?ect of physical illness. Elderly people are often referred to as being ‘confused’; unfortunately this term is often inappropriately applied to a wide range of eccentricities of speech and behaviour as if it were a diagnosis. It can be applied to a patient with the early memory loss of DEMENTIA – forgetful, disorientated and wandering; to the dejected old person with depression, often termed pseudo-dementia; to the patient whose consciousness is clouded in the delirium of acute illness; to the paranoid deluded sufferer of late-onset SCHIZOPHRENIA; or even to the patient presenting with the acute DYSPHASIA and incoherence of a stroke. Drug therapy may be a cause, especially in the elderly.
Delirium tremens is the form of delirium most commonly due to withdrawal from alcohol, if a person is dependent on it (see DEPENDENCE). There is restlessness, fear or even terror accompanied by vivid, usually visual, hallucinations or illusions. The level of consciousness is impaired and the patient may be disorientated as regards time, place and person.
Treatment is, as a rule, the treatment of causes. (See also ALCOHOL.) As the delirium in fevers is due partly to high temperature, this should be lowered by tepid sponging. Careful nursing is one of the keystones of successful treatment, which includes ensuring that ample ?uids are taken and nutrition is maintained.... delirium
Dumbness is the inability to pronounce the sounds that make up words. DEAFNESS is the most important cause, being due to a congenital brain defect, or acquired brain disease, such as tertiary SYPHILIS. When hearing is normal or only mildly impaired, dumbness may be due to a structural defect such as tongue-tie or enlarged tonsils and adenoids, or to ine?cient voice control, resulting in lisping or lalling. Increased tension is a common cause of STAMMERING; speech disorders may occasionally be of psychological origin.
Normal speech may be lost in adulthood as a result of a STROKE or head injury. Excessive use of the voice may be an occupational hazard; and throat cancer may require a LARYNGECTOMY, with subsequent help in communication. Severe psychiatric disturbance may be accompanied by impaired social and communication skills. (See also VOICE AND SPEECH.)
Treatment The underlying cause of the problem should be diagnosed as early as possible; psychological and other specialist investigations should be carried out as required, and any physical defect should be repaired. People who are deaf and unable to speak should start training in lip-reading as soon as possible, and special educational methods aimed at acquiring a modulated voice should similarly be started in early childhood – provided by the local authority, and continued as required. Various types of speech therapy or PSYCHOTHERAPY may be appropriate, alone or in conjunction with other treatments, and often the ?nal result may be highly satisfying, with a good command of language and speech being obtained.
Help and advice may be obtained from AFASIC (Unlocking Speech and Language).... speech disorders
Speech therapists form a small independent profession, most of whom work for the National Health Service in community clinics, general practices and hospitals. They may also work in schools or in units for the handicapped, paediatric assessment centres, language units attached to primary schools, adult training centres and day centres for the elderly.
A speech therapist undergoes a four-year degree course which covers the study of disorders of communication in children and adults, phonetics and linguistics, anatomy and physiology, psychology and many other related subjects. Further information on training can be obtained from the College of Speech Therapists.
If the parents of a child are concerned about their child’s speech, they may approach a speech therapist for assessment and guidance. Their general practitioner will be able to give them local addresses or they should contact the district speech therapist. Adults are usually referred by hospital consultants.
The College of Speech Therapists keeps a register of all those who have passed a recognised degree or equivalent quali?cation in speech therapy. It will be able to direct you to your nearest NHS or private speech therapist.... speech therapy
Word deafness is an associated condition in which, although hearing remains perfect, the patient has lost the power of referring the names heard to the articles they denote. (See also DYSPHASIA.)... word blindness
Tumours All masses cause varying combinations of headache and vomiting – symptoms of raised pressure within the inexpansible bony box formed by the skull; general or localised epileptic ?ts; weakness of limbs or disordered speech; and varied mental changes. Tumours may be primary, arising in the brain, or secondary deposits from tumours arising in the lung, breast or other organs. Some brain tumours are benign and curable by surgery: examples include meningiomas and pituitary tumours. The symptoms depend on the size and situation of the mass. Abscesses or blood clots (see HAEMATOMA) on the surface or within the brain may resemble tumours; some are removable. Gliomas ( see GLIOMA) are primary malignant tumours arising in the glial tissue (see GLIA) which despite surgery, chemotherapy and radiotherapy usually have a bad prognosis, though some astrocytomas and oligodendronogliomas are of low-grade malignancy. A promising line of research in the US (in the animal-testing stage in 2000) suggests that the ability of stem cells from normal brain tissue to ‘home in’ on gliomal cells can be turned to advantage. The stem cells were chemically manipulated to carry a poisonous compound (5-?uorouracil) to the gliomal cells and kill them, without damaging normal cells. Around 80 per cent of the cancerous cells in the experiments were destroyed in this way.
Clinical examination and brain scanning (CT, or COMPUTED TOMOGRAPHY; magnetic resonance imaging (MRI) and functional MRI) are safe, accurate methods of demonstrating the tumour, its size, position and treatability.
Strokes When a blood vessel, usually an artery, is blocked by a clot, thrombus or embolism, the local area of the brain fed by that artery is damaged (see STROKE). The resulting infarct (softening) causes a stroke. The cells die and a patch of brain tissue shrinks. The obstruction in the blood vessel may be in a small artery in the brain, or in a larger artery in the neck. Aspirin and other anti-clotting drugs reduce recurrent attacks, and a small number of people bene?t if a narrowed neck artery is cleaned out by an operation – endarterectomy. Similar symptoms develop abruptly if a blood vessel bursts, causing a cerebral haemorrhage. The symptoms of a stroke are sudden weakness or paralysis of the arm and leg of the opposite side to the damaged area of brain (HEMIPARESIS), and sometimes loss of half of the ?eld of vision to one side (HEMIANOPIA). The speech area is in the left side of the brain controlling language in right-handed people. In 60 per cent of lefthanders the speech area is on the left side, and in 40 per cent on the right side. If the speech area is damaged, diffculties both in understanding words, and in saying them, develops (see DYSPHASIA).
Degenerations (atrophy) For reasons often unknown, various groups of nerve cells degenerate prematurely. The illness resulting is determined by which groups of nerve cells are affected. If those in the deep basal ganglia are affected, a movement disorder occurs, such as Parkinson’s disease, hereditary Huntington’s chorea, or, in children with birth defects of the brain, athetosis and dystonias. Modern drugs, such as DOPAMINE drugs in PARKINSONISM, and other treatments can improve the symptoms and reduce the disabilities of some of these diseases.
Drugs and injury Alcohol in excess, the abuse of many sedative drugs and arti?cial brain stimulants – such as cocaine, LSD and heroin (see DEPENDENCE) – can damage the brain; the effects can be reversible in early cases. Severe head injury can cause localised or di?use brain damage (see HEAD INJURY).
Cerebral palsy Damage to the brain in children can occur in the uterus during pregnancy, or can result from rare hereditary and genetic diseases, or can occur during labour and delivery. Severe neurological illness in the early months of life can also cause this condition in which sti? spastic limbs, movement disorders and speech defects are common. Some of these children are learning-disabled.
Dementias In older people a di?use loss of cells, mainly at the front of the brain, causes ALZHEIMER’S DISEASE – the main feature being loss of memory, attention and reasoned judgement (dementia). This affects about 5 per cent of the over-80s, but is not simply due to ageing processes. Most patients require routine tests and brain scanning to indicate other, treatable causes of dementia.
Response to current treatments is poor, but promising lines of treatment are under development. Like Parkinsonism, Alzheimer’s disease progresses slowly over many years. It is uncommon for these diseases to run in families. Multiple strokes can cause dementia, as can some organic disorders such as cirrhosis of the liver.
Infections in the brain are uncommon. Viruses such as measles, mumps, herpes, human immunode?ciency virus and enteroviruses may cause ENCEPHALITIS – a di?use in?ammation (see also AIDS/HIV).
Bacteria or viruses may infect the membrane covering the brain, causing MENINGITIS. Viral meningitis is normally a mild, self-limiting infection lasting only a few days; however, bacterial meningitis – caused by meningococcal groups B and C, pneumococcus, and (now rarely) haemophilus – is a life-threatening condition. Antibiotics have allowed a cure or good control of symptoms in most cases of meningitis, but early diagnosis is essential. Severe headaches, fever, vomiting and increasing sleepiness are the principal symptoms which demand urgent advice from the doctor, and usually admission to hospital. Group B meningococcus is the commonest of the bacterial infections, but Group C causes more deaths. A vaccine against the latter has been developed and has reduced the incidence of cases by 75 per cent.
If infection spreads from an unusually serious sinusitis or from a chronically infected middle ear, or from a penetrating injury of the skull, an abscess may slowly develop. Brain abscesses cause insidious drowsiness, headaches, and at a late stage, weakness of the limbs or loss of speech; a high temperature is seldom present. Early diagnosis, con?rmed by brain scanning, is followed by antibiotics and surgery in hospital, but the outcome is good in only half of affected patients.
Cerebral oedema Swelling of the brain can occur after injury, due to engorgement of blood vessels or an increase in the volume of the extravascular brain tissue due to abnormal uptake of water by the damaged grey (neurons) matter and white (nerve ?bres) matter. This latter phenomenon is called cerebral oedema and can seriously affect the functioning of the brain. It is a particularly dangerous complication following injury because sometimes an unconscious person whose brain is damaged may seem to be recovering after a few hours, only to have a major relapse. This may be the result of a slow haemorrhage from damaged blood vessels raising intracranial pressure, or because of oedema of the brain tissue in the area surrounding the injury. Such a development is potentially lethal and requires urgent specialist treatment to alleviate the rising intracranial pressure: osmotic agents (see OSMOSIS) such as mannitol or frusemide are given intravenously to remove the excess water from the brain and to lower intracranial pressure, buying time for de?nitive investigation of the cranial damage.... brain, diseases of
Voice This has three varying characteristics: loudness, pitch, and quality or timbre. Loudness depends on the volume of air available and therefore on the size of the chest and the strength of its muscles. Pitch is determined by larynx size, the degree of tenseness at which the vocal cords are maintained, and whether the cords vibrate as a whole or merely at their edges.
In any given voice, the range of pitch seldom exceeds two and a half octaves. Typically, the small larynx of childhood produces a shrill or treble voice; the rapid growth of the larynx around PUBERTY causes the voice to ‘break’ in boys. Changes in the voice also occur at other ages as a result of the secondary action of the SEX HORMONES. Generally speaking, the adult voice is bass and tenor in men, contralto or soprano in women. Timbre is due to di?erences in the larynx, as well as to voluntary changes in the shape of the mouth.
Speech Rapid modi?cations of the voice, produced by movements of the PALATE, tongue and lips. Infants hear the sounds made by others and mimic them; hence the speech centres in the BRAIN are closely connected with those of hearing.
Defects of speech See below, and also SPEECH DISORDERS. MUTISM, or absence of the power to speak, may be due to various causes. LEARNING DISABILITY that prevents the child from mimicking the actions of others is most common; in other cases the child has normal intelligence but some neurological disorder, or disorder of the speech organs, is responsible. Alternatively, complete DEAFNESS or early childhood ear disease may be the cause. STAMMERING is a highly individual condition, but is basically a lack of coordination between the di?erent parts of the speech mechanism. (See also main entry on STAMMERING.) DYSPHASIA is the inability to speak or understand speech, most commonly following brain disease, such as STROKE. APHONIA or loss of voice may be caused by LARYNGITIS or, rarely, a symptom of conversion and dissociative mental disorders – traditionally referred to as HYSTERIA. It is generally of short duration.... voice and speech
Early onset Alzheimer’s disease, in which symptoms develop before age 60, is inherited as a dominant disorder. Late onset Alzheimer’s disease is associated with a number of genes, including 3 that
are responsible for the production of the blood protein apolipoprotein E. These genes also result in the deposition of a protein called beta amyloid in the brain. Other chemical abnormalities may include deficiency of the neurotransmitter acetylcholine.
The features of Alzheimer’s disease vary, but there are 3 broad stages. At first, the person becomes increasingly forgetful, and problems with memory may cause anxiety and depression. In the 2nd stage, loss of memory, particularly for recent events, gradually becomes more severe, and there may be disorientation as to time or place. The person’s concentration and numerical ability decline, and there is noticeable dysphasia (inability to find the right word). Anxiety increases, mood changes are unpredictable, and personality changes may occur. Finally, confusion becomes profound. There may be symptoms of psychosis, such as hallucinations and delusions. Signs of nervous system disease, such as abnormal reflexes and faecal or urinary incontinence, begin to develop.
Alzheimer’s disease is usually diagnosed from the symptoms, but tests including blood tests and CT scanning or MRI of the brain may be needed to exclude treatable causes of dementia.
The most important aspect of treatment for Alzheimer’s disease is the provision of suitable nursing and social care for sufferers and support for their relatives. Tranquillizer drugs can often improve difficult behaviour and help with sleep. Treatment with drugs such as donepezil and rivastigmine may slow the progress of the disease for a time, but side effects such as nausea and dizziness may occur.... alzheimer’s disease
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