Aphasia Health Dictionary

Dysphasia is the term used to describe the dif?culties in understanding language and in self-expression, most frequently after STROKE or other brain damage. When there is a total loss in the ability to communicate through speech or writing, it is known as global aphasia. Many more individuals have a partial understanding of what is said to them; they are also able to put their own thoughts into words to some extent. The general term for this less severe condition is dysphasia. Individuals vary widely, but in general there are two main types of dysphasia. Some people may have a good understanding of spoken language but have di?culty in self-expression; this is called expressive or motor dysphasia. Others may have a very poor ability to understand speech, but will have a considerable spoken output consisting of jargon words; this is known as receptive or sensory dysphasia. Similar diffculties may occur with reading, and this is called DYSLEXIA (a term more commonly encountered in the di?erent context of children’s reading disability). Adults who have suffered a stroke or another form of brain damage may also have di?culty in writing, or dysgraphia. The speech therapist can assess the ?ner diagnostic pointsand help them adjust to the effects of the stroke on communication. (See SPEECH THERAPY.)

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.... dysphasia

Loss of power to express ideas by writing. (See APHASIA.)... agraphia

Alexia is another name for WORD BLINDNESS. (See also APHASIA; DYSLEXIA.)... alexia

The plugging of a small blood vessel by an EMBOLUS which has been carried through the larger vessels by the bloodstream. It is due usually to fragments of a clot which has formed in some vessel, or to small portions carried o? from the edge of a heart-valve when this organ is diseased. However, the plug may also be a small mass of bacteria, or a fragment of a tumour, or even a mass of air bubbles sucked into the veins during operations on the neck. The result is usually more or less destruction of the organ or part of an organ supplied by the obstructed vessel. This is particularly the case in the BRAIN, where softening of the brain, with APHASIA or a STROKE, may be the result. If the plug is a fragment of malignant tumour, a new growth develops at the spot; if it is a mass of bacteria, an ABSCESS forms there. Air-embolism occasionally causes sudden death in the case of wounds in the neck, the air bubbles completely stopping the ?ow of blood. Fat-embolism is a condition which has been known to cause death

– masses of fat, in consequence of such an injury as a fractured bone, ?nding their way into the circulation and stopping the blood in its passage through the lungs. (See also PULMONARY EMBOLISM.)... embolism

The following conditions are discussed under their individual headings: APHASIA; BRAIN, DISEASES OF; CATALEPSY; CHOREA; CRAMP; EPILEPSY; HYSTERIA; LEARNING DISABILITY; MEMORY; MENTAL ILLNESS; MULTIPLE SCLEROSIS (MS); NERVES, INJURIES TO; NEURALGIA; NEURITIS; PARALYSIS; PSYCHOSOMATIC DISEASES; SPINE AND SPINAL CORD, DISEASES AND INJURIES OF; STROKE; TABES.... nervous system, disorders of

Defects and disorders of the brain, which may have one of numerous causes including infection, injury, brain tumour, or a lack of blood or oxygen (hypoxia). Because the brain is encased in the skull, any space-occupying tumour, brain abscess, or haematoma creates raised pressure, which impairs the function of the whole brain. Brain disorders that are localized in a small region may affect a specific function such as speech (see aphasia). More often, damage is more diffuse and the symptoms can be varied and numerous. Some brain disorders are congenital due to genetic or chromosomal disorders, as in Down’s syndrome. Structural defects that arise during the development of the fetus in the womb include hydrocephalus and anencephaly.

Reduced oxygen supply may occur at birth, causing cerebral palsy. Later in life, cerebral hypoxia can result from choking or from arrest of breathing and heartbeat. From middle age onwards, cerebrovascular disease is the most important cause of brain disorder. If an artery within the brain becomes blocked or ruptures, leading to haemorrhage, the result is a stroke. The brain may also be damaged by a blow to the head see head injury).

Infection within the brain (encephalitis) may be due to viral infection. Infection of the membranes surrounding the brain (meningitis) is generally due to bacterial infection. Creutzfeldt–Jakob disease is a rare, fatal brain disease associated with an infective agent called a prion which, in some cases, has been linked with (bovine spongiform encephalopathy), a disease in cattle.

Multiple sclerosis is a progressive disease of the brain and spinal cord. Degenerative brain diseases include Alzheimer’s disease and Parkinson’s disease. Emotional or behavioural disorders are generally described as psychiatric illnesses; but the distinction between neurological and psychiatric disorders is now much less clear.... brain, disorders of

n. a form of *aphasia in which the patient is unable to give the names of objects, although retaining an understanding of their use and the ability to put words together into speech. It sometimes occurs after a stroke or in certain types of dementia.... anomia

n. absence or loss of the voice caused by disease of the larynx or mouth or by disease of the nerves and muscles involved in the generation and articulation of speech. If loss of speech is due to a language defect in the cerebral hemispheres, the disorder is *aphasia.... aphonia

n. the forewarning of an epileptic or migrainous attack. An epileptic aura (sometimes known as the preictal phase, because it precedes the main *ictus or seizure) may take many forms, such as an odd smell or taste. The migrainous aura may affect the patient’s eyesight with visual phenomena, such as fortification spectra (zigzag lines) or scotomas (black holes in the visual field), but it may also result in pins and needles, weakness of the limbs, or *aphasia.... aura

A term used if a baby or young child has not achieved new abilities within the normal time range. Normally, new abilities and new patterns of behaviour appear at given ages, and existing patterns of behaviour change and sometimes disappear (see child development).

Delays vary in severity and may affect the development of hand–eye coordination, walking, listening, language, speech, or social interaction. Delay may first be noticed by parents or detected during a routine developmental check.

There are many causes of developmental delay. A child who is late in most aspects of development usually has a generalized problem. This may be due to severe visual or hearing impairment, limited intellectual abilities (see learning difficulties), or damage to the brain before, during, or after birth.

Specific areas of delay may occur in movement and walking. Often there is no serious cause. However, specific causes may include muscular dystrophy and spina bifida. Delay in developing manipulative skills is often due to lack of adequate stimulation.

A lack of response to sound may be due to deafness. Autism is a rare cause of unresponsiveness to the human voice although hearing is normal. A hearing problem may cause delayed speech. Twins are often late talkers. Any generalized difficulty with muscle control can affect speech production; this may occur in children with cerebral palsy. Damage to, or structural defects of, the speech muscles, larynx (voice box), or mouth may also cause speech difficulties, as may any disorder affecting the speech area of the brain (see aphasia; dysarthria; dysphonia; speech disorders). Delay in bladder and bowel control have many possible causes (see encopresis; enuresis; soiling).

A child who shows signs of developmental delay should undergo a full assessment by a paediatrician.... developmental delay

The body system that gathers and stores information and is in overall control of the body.

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

Defects or disturbances in speech that lead to an inability to communicate effectively.

Damage to the language centres of the brain (usually due to a stroke, head injury, or brain tumour) leads to aphasia, which may impair speech.

Disorders of articulation may be caused by damage to nerves that go to muscles in the larynx, mouth or lips, due to stroke, head injury, multiple sclerosis, or Parkinson’s disease. A structural abnormality of the mouth, such as a cleft lip and palate, can also be a cause.

Disorders of voice production include hoarseness and inappropriate pitch or loudness. In many cases, the cause is a disorder affecting closure of the vocal cords (see larynx, disorders of). A voice that is too high or low or too loud or soft may be caused by a hormonal or psychiatric disturbance or by hearing loss.

Disorders of fluency include stuttering, which is marked by hesitant speech and repetition of sounds.

Delayed speech development in a child may be due to hearing loss (see deafness), slow maturation of the nervous system, poor tongue and lip control, lack of stimulation, or emotional disturbance (see developmental delay).

Many people with speech disorders can be helped by speech therapy.... speech disorders

n. difficulty in voice production. This may be due to a disorder of the larynx, pharynx, tongue, or mouth, or it may be *psychogenic. Compare dysarthria; aphasia.... dysphonia

n. a disorder of language in which unintended syllables, words, or phrases are interpolated in the patient’s speech. A severe degree of paraphasia results in speech that is a meaningless jumble of words and sounds, called jargon aphasia.... paraphasia

Damage to part of the brain caused by an interruption to its blood supply. The interruption is most often due to the blockage of a cerebral artery by a blood clot, which may have formed within the artery (see thrombosis), or may have been carried into the artery in the circulation from a clot elsewhere in the body (see embolism). Stroke may also result from localized haemorrhage due to rupture of a blood vessel in or near the brain.

The incidence of stroke rises with age and is higher in men. Certain factors increase the risk. The most important are hypertension and atherosclerosis (and, by association, factors such as smoking that contribute to these disorders). Other risk factors are atrial fibrillation, a damaged heart valve, and a recent myocardial infarction; these can cause clots in the heart which may migrate to the brain.

Symptoms usually develop abruptly and, depending on the site, cause, and extent of brain damage, may include headache, dizziness, visual disturbance, and difficulty in swallowing. Sensation, movement, or function controlled by the damaged area of the brain is impaired. Weakness or paralysis on one side of the body, called hemiplegia, is a common effect of a serious stroke. A stroke that affects the dominant cerebral hemisphere may cause disturbance of language (see aphasia). About a third of major strokes are fatal, a third result in some disability, and a third have no lasting ill effects (see transient ischaemic attack).In some cases, urgent treatment may improve the chances of recovery.

ECG, CT scanning, chest X-rays, blood tests, angiography, and MRI may be used to investigate the cause and extent of brain damage.

If a stroke is proven by scan to be due to thrombosis, thrombolytic drugs may be given.

Anticoagulants may be given if there is an obvious source of an embolism, such as atrial fibrillation or a narrowed carotid artery.

In some cases, antiplatelet agents such as aspirin are given.

In most cases, attention to hydration and pressure areas, and good nursing care, are the most important influences on outcome.

Physiotherapy may restore lost movement or sensation; speech therapy may help language disturbances.... stroke

n. inability or refusal to speak. Innate speechlessness most commonly occurs in those who have been totally deaf since birth; this was formerly referred to as deaf-mutism but the term is now deprecated, as it implies wrongly that those affected are unable to make vocal sounds or to communicate effectively in other ways (sign language). Inability to speak may result from brain damage (see aphasia). It may also be caused by depression, psychosis, or psychological trauma, in which case the patient either does not speak at all or speaks only to particular persons or in particular situations. This latter condition is called selective mutism.

Treatment of mutism due to psychological causes is now increasingly by behavioural means, such as *prompting: people that the patient does not address are slowly introduced into the situation where the patient does speak. This may be done either alone or in combination with more traditional psychotherapy. Psychotic or depressive mutism or *catatonia are addressed by treating the underlying condition. —mute adj., n.... mutism