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  1. Introduction
    1. Acquired brain injuries are biological and traceable to destruction of brain tissue or biochemical imbalances in brain
    2. Major effect is on cognitive processes such as memory
  2. Problems in Diagnosis
    1. Identifying an Acquired Brain Injury
      1. Symptoms of acquired brain injury resemble those of psychological disorders
      2. Symptoms of brain injury complicated by emotional disturbances that develop in response to impairment
      3. Before modern diagnostic technique, differentiation between brain injury and psychological disorders was difficult
      4. Diagnosing psychological disorder as brain injury may also occur
      5. Misdiagnosis can be fatal
      6. A number of resources are available for diagnosis
    2. Specifying the Type of Disorder
      1. Difficult to specify source of impairment in acquired brain injuries
      2. Confusion comes from several sources
        1. Symptoms of brain injuries overlap considerably
        2. Same injury may produce widely different symptoms, depending on location in brain
        3. Source of brain injury is only one of many factors that determine behavioral responses
        4. There are many brain injuries about which very little is known
      3. Delirium
        1. Delirium is transient, global disorder of cognition and attention
          1. Thinking is disorganized
          2. In half of cases, hallucinations and delusions are present
          3. Emotional lability is common
          4. Onset is sudden and severity fluctuates during course of day
          5. Recovery is complete and patient is amnestic
        2. Caused by widespread disruption of cerebral metabolism and neurotransmission
        3. Causes included intoxication medication, surgery, withdrawal from drugs, head injury
        4. Physical illness may cause delirium
          1. Often mistaken for dementia
          2. Misdiagnosis may be fatal
        5. Treatment of delirium is removal of its cause
      4. Specific Cognitive Impairments
        1. Impairment of attention and arousal
        2. Impairment of language function
        3. Impairment of learning and memory
        4. Impairment of visual-perceptual function
        5. Impairment of motor skills
        6. Impairment of executive function
        7. Impairment of higher-order intellectual functions
        8. Impairments of language function called aphasia are common
          1. Fluent aphasia produces streams of incoherent speech
          2. Nonfluent aphasia involves difficulty initiating speech and responding to questions with short answers
          3. Aphasia caused by injury to left hemisphere
          4. Impairments of ability to recognize familiar objects called agnosia
      5. Dementia
        1. Dementia involves impairment in at least two cognitive functions, which leads to decline in performance, compromising occupation or social functioning
        2. Some dementias caused by infectious diseases
        3. Some dementias caused by progressive physical deterioration
    3. Specifying the Site of the Damage
      1. Damage may be diffused throughout brain as in degenerative disorders
      2. Damage may be restricted to specific area
      3. CT, PET, and MRI are primary methods to pinpoint site of brain damage
  3. Types of Acquired Brain Injuries
    1. Cerebral Infection
      1. Cerebral infections caused by bacteria, viruses, protozoa, and fungi
      2. Cerebral Abscess
        1. Cerebral abscess is infection that becomes encapsulated by connective tissue
        2. It cannot drain and heal and it continues to grow
        3. Infection occurs in body and travels to brain
      3. Encephalitis
        1. Encephalitis is generic term that refers to inflammation of brain
        2. Caused by viral or non-viral agents
        3. Typically transmitted by mosquitoes, ticks, and horses
        4. Symptoms include seizures, delirium, lethargy, and brain damage
      4. Mad Cow Disease
        1. Mad cow disease is type of spongiform encephalopathy that attacks brain
        2. In humans, called Creutzfeldt-Jakob disease
        3. Symptoms include memory impairments, behavioral change, difficulty walking, visual perception deterioration
        4. Brain has widespread degeneration and protein deposits
      5. Meningitis
        1. Meningitis is acute inflammation of the meninges
        2. Infection may be introduced through body infection or outside agent entering skull
        3. Drowsiness, confusion, irritability, problems with concentration, memory defects, and sensory impairments are symptoms
      6. Neurosyphilis
        1. Neurosyphilis is deterioration of brain tissue due to syphilis
        2. Degenerative disorder called general paresis linked to syphilis in late 19th century
        3. Incidence of syphilis has dramatically decreased
      7. AIDS Dementia
        1. AIDS dementia seen in 15% of those diagnosed with AIDS
        2. Appears in late stages of AIDS
        3. Early symptoms often go unnoticed or mistaken for other problems
        4. First signs are cognitive changes such as forgetfulness; later confusions, disorientation, and poor coordination
        5. AIDS dementia often caused by other infectious agents
        6. Damage to brain is often diffused
      8. Groups at Risk for Cerebral Infections
        1. Common illnesses may be related to encephalitis
        2. People at risk for herpes infection also at risk for encephalitis
        3. Organisms that cause cerebral infections are transmitted through insect and rodent bites
        4. People living in different locations are at risk for different types of cerebral infections
      9. Treatment of Cerebral Infections
        1. Treatment depends on type of infection
        2. Bacterial and fungal infections are treatable
        3. Viral infections are more challenging to treat
        4. Some argue that HIV infection may be reversible in early stages; secondary infections that may lead to AIDS dementia may be eliminated
        5. Family support and memory aids are important
    2. Traumatic Brain Trauma
      1. Brain trauma is injury to brain due to jarring, bruising, or cutting
      2. Traumatic head injury is leading cause of disability and death in children and young adults
      3. Most victims show long-term disabilities
      4. Concussion
        1. A concussion results from blow to head that momentarily disrupts brain function
        2. Temporary loss of consciousness and subsequent amnesia prior to injury is usual result
        3. The longer unconsciousness lasts, the more severe the symptoms and less likely person will recover completely
        4. Aftereffects may be experienced months or years later
      5. Contusion
        1. A contusion is injury that occurs when brain is bruised
        2. Person lapses into coma for hours or even days
        3. Victim may experience traumatic delirium, which disappears within a week
        4. More severe injury leads to permanent instability and intellectual impairment
        5. Repeated head injuries can result in cumulative damage
        6. Boxers may be susceptible to ementia pugilistica and other structural changes in brain
      6. Laceration
        1. In a laceration, an object ruptures and destroys brain tissue
        2. Most serious form of brain trauma
        3. Damage may result in death, extreme disability, or minor disability, but depends on site of damage
        4. Typically results in physical impairment or personality change
      7. Groups at Risk
        1. Two-thirds of victims are males in highest risk age group, 15- to 24-year-olds
        2. Falls are second most common cause of head injury
        3. Most common cause is automobile and motorcycle accidents
      8. Treatment of Brain Trauma
        1. Many head injuries are devastating
        2. Rehabilitation can range from intensive inpatient treatment to periodic outpatient treatment
    3. Cerebrovascular Accidents (CVA): Strokes
      1. Cerebrovascular accidents are known as strokes and involve blockage or breaking of blood vessel in brain, damaging tissue
      2. Third leading cause of death
      3. Marked by stroke syndrome, which is acute onset of specific disabilities involving the CNS
      4. Many people have small CVAs that occur in less critical areas of brain; less noticeable effects on behavior occur
        1. Infarction occurs when supply of blood to brain is cut off leading to death of brain tissue
          1. An embolism is a ball of fat, air, or clot that breaks off from side of vessel and clogs vessel too narrow to let it pass
          2. Thrombosis involves fatty material that gradually builds up and blocks flow of blood in vessel
        2. Hemorrhage occurs when blood vessel in brain ruptures causing blood to spill out into brain tissue
          1. Often caused by hypertension
          2. In brain, hemorrhage is usually due to aneurysms
      5. The Effects of a Stroke
        1. Aftereffects depend on nature of stroke, extent of damage, and location of damage
        2. Typical effects are aphasia, agnosia, apraxia, and paralysis
        3. Most common stroke is due to infarction due to thrombosis in left-middle cerebral artery causing aphasia and impairment on right side of body
        4. Emotional disturbances usually accompany CVAs either as part of injury or reaction to impairment
        5. In some patients, behavioral symptoms may disappear while others are remedied through rehabilitation
        6. In general, the younger the person and the smaller the damaged area, the better the chance of recovery
      6. Groups at Risk
        1. Clearest risk factor for CVA is age
        2. Men are more vulnerable than women
        3. Other high-risk groups include those with diabetes, family history, African-Americans
        4. High cholesterol, obesity, smoking, and hypertension increase risk
      7. Treatment of Stroke
        1. People often ignore first signs of stroke
        2. Important to seek treatment at first sign of symptoms
        3. Medications can limit effects of stroke if given in a timely manner
    4. Brain Tumors (neoplasms)
      1. Brain tumors classified in two ways
        1. Metastic brain tumors originate in different part of body and spread (metatasize) to brain
        2. Primary brain tumors originate in brain; may be intracerebral and extracerebral
      2. First signs of brain tumor are subtle and insidious
      3. Progressive destruction, patient develops at least one of several symptoms
      4. Symptoms related to location of tumor in brain; as tumor grows, adjacent areas of brain and their functions are affected
      5. Groups at Risk
        1. Not much is known about risk factors
        2. Some cancers metastasize to brain
        3. Smoking increases risk for lung cancer
      6. Treatment of Brain Tumors
        1. Some tumors are surgically removed
        2. Radiation treatment may be used if surgery would destroy language and major motor areas
        3. Surgery, chemotherapy, and radiation are used in combination
    5. Degenerative Disorders
      1. Degenerative disorders consist of syndromes characterized by general deterioration of intellectual, emotional, and motor functioning due to progressive pathological change in brain
      2. Symptoms vary depending on site of damage
      3. Aging and Dementia
        1. Dementia is severe mental deterioration and was believed to be a natural part of aging
        2. Dementia is result of degenerative brain disorders
        3. Almost all old people show some psychological changes due to normal aging
        4. Dementias are pathological and result of organic deterioration of brain
        5. Diagnosis of syndromes is difficult
          1. Many other problems mimic symptoms of dementia
          2. Alzheimer's disease difficult to distinguish from other dementias
          3. There is considerable overlap of symptoms
          4. Symptoms often related to person's premorbid personality and psychosocial history
      4. Alzheimer's Disease
        1. Alzheimer's disease is most common form of dementia
        2. Autopsies reveal neurofibrillary tangles and senile plaques
        3. Primary symptoms are cognitive deficits, especially loss of memory
        4. Early signs include irritability and failure of concentration and memory
        5. Symptoms create difficulties for families of Alzheimer's patients
        6. Rate of progression is highly variable
        7. Research suggests a genetic role and may involve several genetic abnormalities
          1. May be related to Down syndrome and chromosome 21
          2. Production of amyloid may be controlled by genes on chromosome 21
          3. Other chromosomes may be implicated as well
          4. Buildup of beta amyloid may be caused by breakdown of several regulatory mechanisms each controlled by a different gene
        8. Research suggests that Alzheimer's may have multiple contributing factors
      5. Lewy Body Disease
        1. Lewy body disease may be second most common degenerative brain disease
        2. Rounded structures in neurons throughout brain are found
        3. Clinicians must rely on analysis of patient's symptoms for diagnosis
        4. Symptoms of Lewy body disease are similar to those of Alzheimer's disease
        5. Fluctuations in day-to-day functioning seen in Lewy body disease
        6. Most cases involve memory impairment followed by symptoms of Parkinson's disease
      6. Vascular Dementia
        1. Vascular dementia is cumulative effect of several CVAs
        2. Common symptoms include blackouts, heart problems, kidney failure; psychological symptoms include language and memory defects, emotional lability, and depression
      7. Huntington's Chorea
        1. Huntington's chorea is genetically transmitted
        2. The basal ganglia is damaged; area is responsible for posture, muscle tonus, and motor coordination
        3. Early signs include vague behavioral and emotional changes
        4. Involuntary, spasmodic jerking of limbs characterize disorder
        5. Increasingly bizarre behavior is seen in patients
      8. Parkinson's Disease
        1. Parkinson's disease involves damage to basal ganglia, especially substantia nigra
        2. Cause is unknown, but may be related to heredity, viruses, toxins, head trauma
        3. Primary symptom is tremors that are present during rest, but diminish or cease when person is sleeping
        4. Another symptom is an expressionless, masklike countenance
        5. Patients walk in a distinctive slow, stiff gait
        6. Many patients also experience psychological disturbances such as memory, learning, judgment and concentration problems, and dementia
      9. Groups at Risk
        1. Since women live longer, more women will experience dementia
        2. Percentage of men who will develop dementia is same
        3. Age and gender related to type dementia an individual is likely to develop
        4. Educational level may affect incidence or rate of diagnosis of Alzheimer's disease
        5. Some stroke patients developed vascular dementia with high blood pressure, a risk factor
        6. A test now exists to identify defective gene that causes Huntington's chorea
      10. Treatment of Degenerative Disorders
        1. Drugs that increase levels of acetylcholine have been used to treat Alzheimer's disease
        2. There is no cure and little treatment for Alzheimer's disease
          1. Behavioral therapy may suppress some symptoms
          2. Most common treatment is custodial care
          3. Many patients are able to remain at home with their families, especially if family can receive support services
        3. High blood pressure, diabetes, obesity, and smoking are risk factors for vascular dementia; after damage, decline is irreversible
        4. Drugs that increase amount of dopamine among Parkinson's disease patients can control tremor but do not cure it
    6. Nutritional (and vitamin) Deficiencies
      1. Insufficient intake of essential vitamins can result in neurological damage and psychological disturbances
      2. Beriberi and pellagra are two common syndromes in less industrial countries
      3. Korsakoff's Syndrome--a psychosis related to alcoholism
        1. Primary pathological is deficiency of B12 or thiamine
        2. There are two classic behavioral signs of Korsakoff's psychosis
          1. Anterograde amnesia is inability to incorporate new memories
          2. Confabulation is tendency to fill in memory gaps with invented stories
        3. Suggests a psychotic impairment of judgment and spreads to other aspects of psychological impairment
    7. Endocrine Disorders
      1. Endocrine glands produce hormones that affect bodily mechanisms
      2. Thyroid Syndromes
        1. Hyperthyroidism involves excessive secretion of thyroxin, which leads to physical and psychological difficulties
        2. Hypothyroidism involves deficient secretion of thyroxin, which leads to physical and psychological difficulties
      3. Adrenal Syndromes
        1. Addison's disease refers to chronic underactivity of adrenal glands, which leads to physical and psychological changes
        2. Cushing's syndrome refers to adrenal cortex overactivty leading to physical and psychological changes
    8. Toxic Disorders
      1. Lead
        1. Excessive ingestion of lead causes lead encephalopathy, leading to extreme pressure in the brain
        2. Most common victims are children and may be related to mental retardation
        3. There are a number of sources of lead contamination
      2. Other Heavy-Mental Toxins
        1. Victims of toxins typically have jobs where they come into contact with mercury and manganese
        2. Other victims come into contact in other ways such as food or air contamination--for example, fish from water polluted by mercury wastes
        3. Mercury poisoning causes memory loss, irritability, and difficulty in concentration
        4. Later, it causes tunnel vision, motor problems, coma, and death
      3. Psychoactive Drugs
        1. Alcohol, opiates, and amphetamines can cause severe psychological disturbances
        2. Inhalation of aerosol gases and glues has become more popular way to get high
      4. Carbon Monoxide
        1. Carbon monoxide combines with hemoglobin to prevent blood from absorbing oxygen
        2. Often results in death; those who survive have a number of psychological consequences such as apathy, confusion, and memory defects
  4. The Epilepsies
    1. Epilepsy is broad term for disorders that have spontaneous seizure caused by disruption of electrical and physiological activity of brain cells
    2. Abnormal activity disrupts functions controlled by affected part of brain
    3. Causes of Epilepsy
      1. Any condition that interferes with brain function can cause epilepsy
      2. Most common cause is brain injury
        1. If epilepsy beings in middle age, most likely cause is brain tumor
        2. If epilepsy begins in older age, cause is most likely to be cerebral vascular disease such as stroke or cerebral arteriosclerosis
      3. When a cause can be identified, it is known as symptomatic epilepsy
      4. When cause is unknown, it is idiopathic epilepsy
    4. Types of Seizure
      1. Partial seizures originate in one part of brain
        1. In simple partial seizure, cognitive functioning remains intact; person may have sensory changes or minor psychological changes
        2. In complex partial seizure, cognitive functioning is interrupted; an aura may precede seizure; person is not able to engage in purposeful activity and does not respond normally
      2. Generalized seizure involves entire brain at outset or soon spreads from one part
        1. Absence seizures involve spaced-out look and sense of being absent from the surroundings
        2. Tonic-clonic seizures begin with a tonic or rigid extension of limbs followed by clinic or jerking movements through body
      3. Each type of seizure requires different kind of drug; therefore, accurate diagnosis is important
    5. Psychological Factors in Epilepsy
      1. Most common complaint is poor memory, since most epilepsies involve temporal lobes
      2. Once thought there was an epileptic personality, but no data support that view
    6. Treatment of Epilepsy
      1. Most people take antiepileptic drugs, which suppress seizures in 80% of patients
      2. Some report side effects of being drugged down
      3. Surgery involves removal of focal epileptic area and is becoming more common





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