appendix 1 Outline Diagrams of the Brain
appendix 2 Glasgow Outcome Scale
appendix 3 Glasgow Coma Scale
appendix 4 Post Traumatic Amnesia

NEGLECT
A common consequence of damage to the right cerebral hemisphere in which the patient ignores (neglects) the right side of space and often the right side of the body (failing to wash or shave or dress the right half of the body). It is not common after head injury except in the very acute early stages.

NEURASTHENIA
A term no longer in use, referring to a neurosis.

NEUROENDOCRINE DISORDER
A wide range of medical complications following damage to important glands in the brain. The most important glands are the hypothalamus and pituitary. Damage to the pituitary or hypothalamus can lead to DIABETES INSIPIDUS (qv), which often recovers spontaneously within the first year after injury. Damage to the hypothalamus can lead to disorders of eating, heat regulation and sleeping.

NEUROPATHOLOGY
The study of the gross and microscopic changes in the brain and nervous system. Neuropathological studies of the brains of patients who died following head injury have been invaluable in identifying the main causes of death and disability (in patients who survive).

NEUROPSYCHOLOGIST
A person with a degree in psychology and specialist training or experience in the practice of neuropsychology. The study and practice of neuropsychology involves the identification, analysis and treatment of the cognitive, behavioural and affective consequences of brain damage.

OCCIPITAL LOBES
The rear part of the brain (see Appendix 1) which is vital in vision. Destruction of both left and right occipital lobes leads to complete blindness ("cortical blindness"), but this is very rare after head injury. However, lesser degrees of visual impairment resulting from occipital damage are often seen.

OCCUPATIONAL THERAPY
A range of treatments administered by Occupational Therapists (OTs). These therapists are specialists in enabling patients to achieve performance in aspects of daily life. These include ACTIVITIES OF DAILY LIVING (qv) or ADLs, such as washing, dressing and toileting, and advanced ADLs, such as planning, budgeting, etc. Occupational therapy may involve practice and training within a hospital or clinic, or within the patient's home. Such therapists may be expert in the use of aids and adaptations to assist patients in ADLs.

OEDEMA
A condition of swelling of tissues. The brain may swell after a severe head injury, and this is a very serious complication necessitating neurosurgical management. The problem is that the swelling, by compressing brain tissue against the skull, or by forcing brain down into the top of the spine can cause death, or further serious brain damage.

OLFACTORY NERVE
One of the cranial nerves (the first nerve). This nerve is responsible for allowing us to smell. Loss of the sense of smell (ANOSMIA - qv) is quite common after head injury as this nerve sits at the front of the brain in an area often damaged in head injury.

ORBITO-MEDIAL CORTEX
See Appendix 1.

PACED AUDITORY SERIAL ADDITION TASK (PASAT)
A demanding test of attention in which the patient hears a series of numbers. He must add the 2nd to the 1st; the 3rd to the 2nd; the 4th to the 3rd; and so on. Performance is often severely impaired after head injury. Along with memory performance, performance on PASAT and similar measures is a key predictor of ability to return to work after brain injury.

PARIETAL LOBE
The part of the brain located above and behind the temples (see Appendix 1). The parietal lobe deals with the perception of touch and the integration of all the senses. Damage here can lead to varied consequences ranging from a difficulty in mathematics (dyscalculia) to a failure to recognise previously well-known faces.

PASAT
See PACED AUDITORY SERIAL ADDITION TASK.

PENETRATING HEAD INJURY
This kind of head injury is caused by a bullet or other missile. The effects differ from CLOSED HEAD INJURY (qv): in penetrating head injury the particular part of the brain destroyed determines the effects which can be highly variable.

PERFUSION
This is the process by which the brain is supplied with blood and therefore oxygen. The process is complicated and not yet fully understood. Where blood pressure falls, or where INTRACRANIAL HYPERTENSION (qv) creates resistance to normal blood flow, perfusion may be impaired. The damaged brain is less good at making normal adjustments in arterial size to 'autoregulate' blood flow, adding a further complication. Obviously, this problem requires skilled neurosurgical management.

PERSEVERATION
A common consequence of frontal brain damage. The perseverating patient shows inert and often stereotyped behaviour. He is rigid and may repeat action sequences or phrases. He may answer a question in a way that was appropriate for the previous question, but is no longer appropriate.

PERSISTENT VEGETATIVE STATE (PVS)
A state following very severe injury in which patients remain speechless and devoid of any meaningful contact with others. Patients show sleep/wake cycles but no evidence of conscious awareness. The condition is due to very extensive damage to the fibres under the cerebral cortex. PVS should be distinguished from the LOCKED IN STATE (qv).

PERSONALITY
A habitual tendency to feel, think, and behave in certain ways. Personality change is common after severe head injury, particularly when there is damage to the frontal or temporal lobes. The change is very often negative; unpleasant aspects of personality (eg aggression, boastfulness) which before injury were suppressed, may become prominent and may prevent the patient returning to his previous occupation, or even to his family.

PITUITARY
Gland in the base of the skull which secretes hormones necessary for the regulation of various bodily systems.

PLANNING
Disturbances in planning are a common and potentially disabling consequence of damage to the frontal parts of the brain.

POST-CONCUSSIONAL SYNDROME (PCS)
A group of symptoms including headache, vertigo, poor memory and concentration and anxiety and depression. Soon after concussion it is thought that these are a direct result of injury to the brain. If unduly prolonged, it is thought that psychological factors are responsible. Many patients who show a prolonged PCS have signs of premorbid personality or situational factors which are likely to predispose them to develop a neurotic condition. Neuropsychological assessment may clarify the nature of the condition.

POST-TRAUMATIC AMNESIA (PTA)
The period between the injury and regaining day-to-day memory so that the patient knows where he is, what happened to him, etc. The period of PTA always includes the period of coma. PTA duration is a good index of the severity of the underlying brain damage. Its significance is discussed in Appendix 4.

POST-TRAUMATIC EPILEPSY
A well recognised complication of head injury. Predictive factors for the development of epilepsy include haematomas, long post-traumatic amnesia, penetrating injury, depressed fracture and a seizure within the first week after injury. Most patients who go on to develop epilepsy do so within the first 5 years after injury, but the risk may still be present thereafter. For the patient there are the obvious psychosocial consequences (stigma, driving, employer's reluctance) and side effects of some kinds of anticonvulsant medication (slowing, poor memory).

POST-TRAUMATIC PSYCHOSIS
A PSYCHOSIS (qv) following head injury. This is a rare condition found more with missile wounds than the blunt head injuries of civilian life. It has been associated particularly with damage to the TEMPORAL LOBES (qv) of the brain and with dementia.

POST TRAUMATIC STRESS DISORDER (PTSD)
PTSD may arise after an extreme traumatic stressor. Such events may include disasters (natural or man-made), assaults, or serious accidents. It is possible for prolonged stress (eg being a hostage) as well as sudden horrific events to cause PTSD. Symptoms include repeated flashbacks, an inability to stop dwelling on the event, feeling of detachment/estrangement from others, sleep disturbance, and difficulty concentrating. There is now a large medical/scientific literature documenting the various aspects of PTSD, which can be a very long lasting disorder. However, it is very rare after brain injury, as the injured person does not remember the accident/injury due to RETROGRADE AMNESIA (qv) and POST -TRAUMATIC AMNESIA (qv).

PREFRONTAL
The extreme front of the brain. This part of the brain plays a part in many of the "highest" human functions such as planning, envisaging the consequences of actions, recognising the effects of one's behaviour on others, etc, etc. Damage here can leave the patient looking perfectly normal, yet rendering him profoundly inert, "concrete" and simplistic in thinking and behaviour. The resulting personal and social handicap can be very profound.

PREMORBID ABILITY
Level of intellectual ability before a brain injury. This may be gauged in broad terms from the individual's educational/occupational history. There are also specialised neuropsychological tests which can measure previous ability. These tests measure a (verbal) ability which is robust to the effects of brain injury and is also related to IQ. These measures therefore provide a kind of permanent marker of how intelligent someone has been, and can be used (eg) after brain injury, in individuals who are dementing, etc.

PSYCHOMOTOR SEIZURES
A kind of epilepsy arising from scar tissue in the temporal lobes of the brain. The patient shows abnormal repetitive and stereotyped patterns of behaviour.

PSYCHOSIS
A severe disorder of behaviour, feeling, and thinking. Contact with reality is impaired, and there may be hallucinations and delusions. The psychoses may be classified into "organic" (dementia) and "functional" (depression and schizophrenia). Both are very rare sequelae of blunt head injury.

PSYCHOSOCIAL PROBLEMS
The changes in behaviour and affective status in the patient, following head injury, and the effect these changes have on those around the patient, particularly his immediate family.