Glossary of Terms

aphasia: Loss of the ability to express oneself and/or to understand language. There are many different kinds of aphasia. Receptive aphasia refers to the inability to understand what someone else is saying. This is often associated with damage in the temporal area of the brain. Expressive aphasia refers to an inability to express oneself. Some patients may know what they want to say, but many of the words they say may not "make sense". Expressive aphasia is often associated with the left frontal area of the brain.

apraxia: Inability to perform purposeful movements when paralysis is not present. Particularly refers to inability to use objects. For example, a patient may be unable to put together the proper movements to sit cross-legged on the floor or may not know what to do when handed a broom.

astereognosia: Inability to recognize things by touch.

ataxia: Inability to coordinate muscle movements or having irregular muscle movements. This can interfere with the person's ability to walk, talk, eat, perform self-care tasks, and work.

attention: The ability to focus on one subject or bit of information; being able to filter out the relevant from the irrelevant information in one's environment.

behavior modification: The change in behavior produced intentionally by any various learning techniques, especially those of instrumental learning.

brain stem: The lower portion of the brain which connects it to the spinal column. The brain stem coordinates the body's vital functions (breathing, blood pressure, and pulse). It also houses the reticular formation which controls consciousness, drowsiness, and attention.

cerebellum: The portion of the brain which is located below the cortex. The cerebellum is concerned with coordinating movements.

cognition: Knowing, awareness, perceiving objects, thinking, remembering ideas. The learned set of rules on which all thinking is based.

concentration: Sustaining attention to a task over a period of time; remaining attentive.

Contra-coup: When the brain is hit with sufficient force, causing it to "bounce" against the opposite side of the skull, thereby causing injury to both the site of the impact and the part of the brain opposite the impact. (For example, if the impact is to the left frontal area, contra-coup damage may occur to the right occipital area.)

CT scan: A series of x-rays taken at different levels of the brain. A scan often is completed soon after the injury to determine whether surgery is needed. Repeat scans are completed later to see how the brain is recovering.

diffuse: Brain damage which covers many areas of the brain rather than one specific location. Diffuse damage is common in close-head injuries due to the brain moving about and tissue being torn, stretched and bruised.

disinhibition: The inability to control or inhibit impulses and emotions.

disorientation: Not knowing where you are, who you are, or the time. Often, professionals use the term "oriented in all three spheres" or "oriented times three" which refers to person, place, and time.

diplopia: Seeing two images of a single object - "double vision"

dysarthria: Difficulty forming or articulating words. This may be caused by damage to the motor areas of the cortex or damage to the brain stem. Dysarthria may include speech that is slurred, talking extremely fast or slow, or improper pitch.

edema: Collection of fluid in the brain tissue causing swelling.

emotional lability: Exhibiting rapid and drastic changes in emotions; quickly becoming angry, sad, silly, or happy, and being extreme in showing these emotions.

fading: A teaching technique in which a prompt is gradually removed.

frontal lobe: The areas of the brain located at the front on both the left and right sides. This area plays a role in controlling emotions, motivation, social skills, expressive language (in an area on the left side referred to as Broca's area), and inhibition of impulses. The motor strip, controlling movement and motor integration, runs along the posterior (back) of the frontal lobe.

frustration tolerance: The ability to deal with frustrating events in daily life; the point at which a person can no longer control his anger in a situation and responds by yelling, throwing things, or becoming aggressive.

generalization: The tendency, after learning a response to one stimulus, to make that response also to other similar stimuli.

hemiparesis: Weakness of one side of the body (or part of it) due to injury to the motor areas of the brain.

inflexibility: The inability to adjust to everyday changes in routines, usually related to injury to the frontal lobes. Some head-injured persons may have little difficulty following a structured routine but may exhibit sudden frustration and confusion when their routine is changed.

judgement: The process of forming an opinion, based on an evaluation of the situation at hand. "Good" judgement refers to choosing the most optimal course available. Judgement involves cognitive skills, personal values and preferences, and insight into what our abilities and disabilities are. For example, a Resident with judgement deficits may be able to make decisions, but the decisions may be unsafe or unsuccessful.

memory: The process of perceiving information, organizing and storing it, and retrieving it at a later time as needed. Memory is a complex function that involves many parts of the brain working together. There are different types of memory, including immediate (repeating a phone number just related), recent (recalling what occurred the previous day), and remote (recalling the name of a childhood friend).

modeling: Exhibiting a behavior which is intended to teach someone else through the observer's imitation of the desired behavior.

National Head Injury Foundation (NHIF): An organization of families and professionals concerned with the needs of head-injured persons. The organization provides information and support and has chapters in many states. The national office is in Washington, D.C.

occipital lobe: The posterior (back) part of each side of the brain, involved in perceiving and understanding visual information.

over-learning: Continuing to work and memorize material beyond the point which it is adequately mastered.

parietal lobe: The upper middle lobe of each side of the brain, involved in receiving and understanding sensations, and closely linked to speech fluency and writing.

perseveration: Becoming "stuck" on one word or task and not being able to switch back and forth or go on to the next word/task. (For example, a patient may be asked to draw a circle on a piece of paper. He may then be asked to draw a square, but continues drawing circles.)

proximal instability: Impaired strength or muscle tone of the trunk, shoulder girdle, or hip girdle. This can cause poor posture, abnormal movement of the limbs, inability to sit up and inability to hold one's head up, caused by damage to the motor strip of the brain.

problem solving: The ability to evaluate all of the factors involved when faced with a problem, and to generate and evaluate possible solutions. Residents with deficits in this area may "freeze" when faced with a problem; i.e. they may not be able to think of possible solutions and instead will respond by doing nothing

post-traumatic amnesia (PTA): A loss of memory that occurs immediately after injury, and which may continue for weeks or months. During this time, many Residents are unable to organize or retrieve information. The length of PTA is regarded as an indicator of eventual recovery.

quadriparesis: A weakness which involves all four limbs.

reinforcement: A consequence of a response that increases the probability of that response occurring again.

shaping: Inducing an individual to make a completely new response by reinforcing gradually closer and closer approximations to it.

spasticity: An abnormal increase in muscle tone, causing the muscles to resist being stretched. A Resident with spasticity may look "curled up," with arms held close to his chest, or may appear very stiff.

spontaneous recovery: The recovery which takes place spontaneously as the brain heals; this type of recovery occurs with or without rehabilitation and it is often difficult to know how much improvement is spontaneous and how much is due to rehabilitative interventions. It occurs early in the recovery process.

temporal lobe: The lower middle part of each side of the brain, involved in receiving information from the auditory system and involved in memory.

token economy: An arrangement for behavior modification in which appropriate behavior is reinforced with tokens that can later be exchanged for desired activities, objects, or treats (reinforcers).

visual field deficit: Not visually perceiving information in a specific area of the visual field. Often this involves either the left or right half of the field of vision, but may involve a quarter of the visual field, etc.