Chapter 15 Neuropsychology

Chapter 15 Neuropsychology. Copyright © 2019 Cengage Learning. All Rights Reserved..

Learning Objectives (1 of 2). Describe the responsibilities and assessment methods of the neuropsychologist. Explain the major characteristics of Alzheimer’s disease, vascular disease, traumatic brain injury, substance/medication-induced neurocognitive disorders, HIV-associated neurocognitive disorder, and prion diseases.

Learning Objectives (2 of 2). Describe the features of tumors, infections, epilepsy, multiple sclerosis, and migraine headaches Explain the basic principles that predict recovery from brain damage Describe the major methods used to treat neurocognitive disorders.

What Is Neuropsychology?. A specialty field within clinical psychology that seeks to understand and treat patients with cognitive impairments resulting from: Aging Disease Injury.

Who are the Neuropsychologists?. Licensed doctoral level clinical psychologists who complete specialized training Often work in collaboration with neurologists.

Neuropsychological Assessment. Goal is to develop an informed treatment plan Choice of methods depends on the issues involved Standardized tests Comparisons with population Comparisons with abilities unaffected by condition IQ tests Halstead-Reitan battery Condition might affect test performance (e.g., pain, fatigue, medications).

[Audio] Figure 15.1 Neuropsychological Testing Standardized tests are an important part of a neuropsychological assessment..

Neurocognitive Disorders. Described in the Diagnostic and Statistical Manual of Mental Disorders (DSM 5; APA, 2013) Diagnosed when a patient experiences a decline in functioning in one or more cognitive domains after a known challenge to the nervous system Attention Executive function Learning and memory Perception and movement Social cognition.

Alzheimer’s Disease (1 of 4). A neurodegenerative condition associated with aging that results in dementia Probable Alzheimer’s disease is diagnosed on the basis of: Genetic testing or family history Clear evidence of learning and memory impairments A steady, gradual loss of cognitive function without plateaus.

Alzheimer’s Disease (2 of 4). Diagnostic methods Autopsy Biomarkers in CSF and blood PET and MRI scanning Alzheimer’s disease risk increases with age Genetics The e4 variant of the APOE gene People with two copies of e4 are 15 times more likely to develop Alzheimer’s disease as people who do not have an e4 allele. Exercise interacts with genotype.

Alzheimer’s Disease (3 of 4). Can be inherited as a dominant trait due to mutations in either the APP, PSEN1, or PSEN2 genes Atrophy of the cerebral cortex and neurodegeneration Neurofibrillary tangles and tau proteins Beta amyloid protein plaques Oxidative stress Disruption of microRNAs Characteristic pattern of brain damage Transneuronal degeneration.

Alzheimer’s Disease (4 of 4). Decreased connectivity within the default mode network (DMN) Treatments Experimental antibodies targeting beta amyloid clear plaques Approved treatments slow down, but do not reverse the course of the disease Increasing seafood and omega-3 fatty acid intake Acetylcholinesterase inhibitors Use of antipsychotics is associated with earlier death.

[Audio] Figure 15.2 PET Scans for Amyloid A useful adjunct to other diagnostic procedures in cases of suspected Alzheimer's disease is a PET scan that identifies amyloid in the brain. As you can see in this image, the scan of a patient with Alzheimer's disease shows much more amyloid (the brightly colored areas) than the scan of the healthy person..

[Audio] Figure 15.3 APOE Alleles and the Risk for Alzheimer's Disease This image compares the relative frequency of Alzheimer's disease among people with the six possible allele combinations for the APOE gene. Having one or two copies of the ε4 allele of the APOE gene increases a person's risk for Alzheimer's disease. The ε3 allele is the most common form of APOE and does not seem to impact risk for Alzheimer's disease one way or the other. The least common form of APOE, the ε2 allele, appears to convey some protection from Alzheimer's disease. Source: https://www.google.com/patents/WO1994009155A1?cl=en.

[Audio] Figure 15.4 Alzheimer's Disease Produces Structural Abnormalities in Neurons This image illustrates the abnormal structural effects of Alzheimer's disease on neurons. The cone-shaped elements are neurofibrillary tangles, and the brown clumps are amyloid plaques found in the brain of a patient who died from Alzheimer's disease. © ISM/Phototake – All rights reserved..

Vascular Disease (Stroke) (1 of 2). Neurons are totally dependent on the blood supply for oxygen A stroke occurs when the brain’s blood supply is interrupted by either: Cerebral hemorrhage Hypertension Aneurysms The sudden blockage of a blood vessel Results in ischemia (low oxygen levels) Infarct (area of dead neural tissue) Transient ischemic attacks (TIA) Thrombosis vs. embolism.

Vascular Disease (Stroke) (2 of 2). Excess glutamate release produces neural damage through excitotoxicity Neuronal cell death occurs immediately after a stroke, but prompt medical attention can save the neurons and glia in the penumbra Use of drugs that reduce blood clotting Mechanical devices inserted into blood vessels Histone deacetlyase (HDAC) inhibitors Surgery Physical activity.

[Audio] Figure 15.5 The Brain's Blood Supply Due to the brain's enormous need for oxygen, it is supplied by a rich network of blood vessels. Interruptions to this supply produce rapid changes in brain function and, potentially, infarct and death. CNRI/Science Source.

[Audio] Table 15.1 Characteristics of Types of Strike.

[Audio] Figure 15.6 Brain Infarct When an area of the brain is deprived of oxygen for a sufficient amount of time, cells begin to die. The area of dead tissue is referred to as an infarct. In this image, the patient suffered a fatal infarct in the right frontal lobe. James Cavallini/Science Source.

Traumatic Brain Injury (TBI) (1 of 3). Physical damage to the brain Open head injuries Penetration of skull Worst consequences when injury affects: Ventricles Both hemispheres Multiple lobes of the brain Closed head injuries (concussions) Blow to the head Coup, countercoup.

Traumatic Brain Injury (TBI) (2 of 3). Subdural hematoma White matter damage Military TBI Can combine open and closed injuries Can differ from civilian TBI Severe swelling Disruption of blood-brain barrier Damage to blood supply Outcomes of TBI Most individuals recover from concussion in a few weeks.

Traumatic Brain Injury (TBI) (3 of 3). Neurocognitive disorder due to traumatic brain injury Repeated TBI is especially damaging Dementia pugilistica Interactions with e4 allele Treatments for TBI vary widely Medications that inhibit glutamate Medications that enhance dopamine activity Norepinephrine reuptake inhibitors Patient and family education Virtual reality.

[Audio] Figure 15.7 Sources of Military TBI The 7 percent of U.S. combat veterans experiencing TBI as a result of serving in Iraq and Afghanistan between 2004 and 2009 were injured in a variety of situations..

[Audio] Figure 15.8 Coup and Countercoup In concussions, the coup, shown here in blue, is an injury that occurs at the site of the blow. When the blow pushes the brain in the opposite direction, a second area of injury occurs, known as the countercoup, shown here in red..

[Audio] Figure 15.9 Boxers Risk Repeated Head Injuries Boxer Jerry Quarry, shown on the left fighting Muhammad Ali, developed traumatic brain injury (TBI) as a result of repeated concussions. This type of TBI causes slurred speech, memory impairment, lack of coordination, personality changes, and a Parkinson-like syndrome. AP Images.

Substance/Medication-Induced Neurocognitive Disorder (1 of 2).

Substance/Medication-Induced Neurocognitive Disorder (2 of 2).

HIV-Associated Neurocognitive Disorder (HAND). Neurological symptoms result directly or indirectly from HIV or other opportunistic infections HIV does not target neurons; therefore, the virus causes cell death indirectly The initial symptoms are relatively mild: Difficulty concentrating, forgetfulness, decreased work productivity, low sex drive, social withdrawal, general apathy Later symptoms: imbalance, clumsiness, weakness, memory loss and language impairment Contemporary antiretroviral treatments.

[Audio] Figure 15.10 HIV Viral Particles Bud from an Infected Cell In cases of HAND, many cells containing the HIV virus can be observed. In the image shown here, the particles budding from an infected cell burst, leading to further spreading of the virus within the brain. Scott Camazine/Alamy.

Prion Diseases (1 of 2). Transmissible Spongiform Encephalopathies (TSEs) Bovine spongiform encephalopathy (BSE) or mad-cow disease Creutzfeldt-Jakob disease (CJD) Kuru Fatal familial insomnia Progression: psychological disturbances, loss of cognitive function, motor disturbances, death Prions and TSEs Role of abnormal form of prion protein PrPc (normal protein) and PrPsc (abnormal protein).

Prion Diseases (2 of 2). Unraveling the TSE mystery Scrapie in sheep and goats in 18th century England CJD was first described in the 1920s Kuru in the Fore people of New Guinea described in the 1950s; linked to cannibalistic burial rituals BSE and new variant Creutzfeldt-Jakob disease (vCJD) Led to ban on animal carcasses in livestock feed.

[Audio] Figure 15.11 Bovine Spongiform Encephalopathy ("Mad-Cow" Disease) This image shows the characteristic damage to the brain that gives the TSEs the name spongiform..

[Audio] Figure 15.12 Prion Proteins Have Normal and Abnormal Forms It appears that the abnormal PrP (shown in red) can change the structure of normal PrP (shown in green) with which it comes into contact, spreading the condition throughout the nervous system..

[Audio] Figure 15.13 A Sheep with Scrapie Scrapie, a TSE affecting sheep and goats, was first observed 300 years ago in England. The condition was named after the fact that afflicted sheep scraped themselves against other objects, removing much of their wool. Michele Crocheck, USDA, APHIS, VS, NVSL.

[Audio] Figure 15.14 Kuru Occurred Among the Fore of New Guinea This photograph of two Fore women with kuru was among Gadjusek's original field study photos taken in 1960. Both women required the use of a stick to stand, and they died within six months..

[Audio] Figure 15.15 Time Course of the BSE Epidemic in the United Kingdom Steps that have been taken against the BSE epidemic in the United Kingdom are working. The use of sheep, goats, or cattle in animal feed has been banned, and cattle exports to other countries ceased. These data reflect the long incubation periods of TSEs. The benefits of the new feeding practices did not show until several years had passed. In addition, the first related case of vCJD was diagnosed several years after the disease in cattle had been identified and addressed..

Neurocognitive Disorders Due to Other Medical Conditions.

Brain Tumors (1 of 3). Tumors: Independent growths of new tissue that lack purpose Primary tumors of the brain Rare Causes unknown, but radiation is a risk Secondary tumors Arise from glial cells, meninges, and ependymal cells Most common type of tumor until age 19 Malignant versus benign tumors.

Brain Tumors (2 of 3). Symptoms of brain tumors Pressure in the skull Headache, vomiting, double vision, reduced heart rate, reduced alertness, and seizures Specific disruptions related to location Types of tumors Gliomas (>70% of brain tumors) Meningiomas Grades I to IV.

Brain Tumors (3 of 3). Treatment for tumors Surgical removal Whole brain radiation Stereotaxic radiosurgery Ultrasound therapy Chemotherapy limited by blood-brain barrier Thalidomide to starve tumors of blood supply Experimental delivery of stem cells with anticancer genes.

[Audio] Figure 15.17 Brain and CNS Tumors and Age Among children and youth under the age of 19 years, tumors of the brain and central nervous system are the most common type of tumor. Among adults ages 20 and older, however, brain and central nervous system tumors are bypassed by prostate (in men), breast, lung, colon, uterine, and urinary tumors. and central nervous system tumors diagnosed in the United States in 2008-2012. Neuro-oncology, 17(suppl 4), iv1-iv62..

Infections. Neurocysticercosis (pork tape worm eggs) Does not result from pork consumption Produces partial seizures Encephalitis: inflammation of brain after viral infection Primary vs. secondary encephalitis Zika virus and microcephaly Herpes simplex Meningitis: inflammation of meninges Bacterial meningitis Viral meningitis: most common, least dangerous Fungal meningitis is rare.

[Audio] Figure 15.18 Complicated Neurocysticercosis Involves Multiple Infections in the Brain Simple neurocysticercosis usually involves a single cyst and is typical of cases that occur in areas of the world in which the condition is not well established. In the case depicted here, multiple cysts have occurred. These complicated cases usually occur in areas in which the condition is common..

[Audio] Figure 15.19 The Zika Virus and Microcephaly Symptoms of the Zika virus in otherwise healthy adults are not particularly worrisome, but if a pregnant woman contracts the virus, her child might display microcephaly. Microcephaly, which can also be caused by exposure of the fetus to environmental toxins, drugs and alcohol, and other infections (cytomegalovirus, rubella, and varicella), is associated with impaired cognitive development, delays in speech and motor functions, and hyperactivity..

Epilepsy (1 of 2). A seizure is an uncontrolled electrical disturbances in the brain correlated with changes in consciousness Partial seizures Simple: no change in consciousness Complex: altered consciousness Focal area Aura Paroxysmal depolarizing shift (PDS).

Epilepsy (2 of 2). Generalized seizures Symmetrically affect both sides of brain No focal area Activation of circuits connecting the thalamus and cortex Tonic-clonic (grand mal) Absence (petit mal) Treatment for epilepsy Antiepileptic drugs (usually GABA agonists) Surgery Ketogenic diet in children.

[Audio] Figure 15.20 Pathways for the Spread of Partial and Generalized Seizures (a) Partial seizures originate in a focus and spread to cortical and subcortical structures. (b) Generalized seizures do not originate in a focus. Once they begin, generalized seizures spread through the brain symmetrically via connections between the thalamus and cortex..

[Audio] Figure 15.21 EEG Recordings During Generalized Seizures In the upper image, we see recordings made during the stages of a tonic-clonic seizure. The lower image shows recordings made during an absence seizure. These recordings illustrate the characteristic "3/sec spike and wave" pattern that generally accompanies this type of seizure..

Multiple Sclerosis (1 of 2). Autoimmune condition Immune system attacks the oligodendrocytes Demyelination of axons Affects white matter in different locations Possible causes Modest heritability Exposure to viruses (e.g., Epstein-Barr) Lack of vitamin D due to lack of sunlight.

Multiple Sclerosis (2 of 2). Treatment Medications slow progression of the disease Quit smoking Increase exercise.

[Audio] Figure 15.22 Multiple Sclerosis Damages Myelin In cases of multiple sclerosis, the body's immune system attacks the oligodendrocytes myelinating axons of some central nervous system neurons. Consequently, electrical signals are not transmitted efficiently, leading to a variety of cognitive, sensory, and motor deficits..

Migraines. Symptoms of excruciating head pain, nausea, and vomiting for 4–72 hours Risk is much higher for women than for men Migraine generator located in brainstem Trigeminovascular system Calcitonin gene-related peptide (CGRP) Produces increased blood flow and pain Treatments Triptans prevent release of CGRP Botox injections Behavioral adjustments.

[Audio] Figure 15.23 Migraine Aura Many patients with migraine experience an aura, or period of sensory distortion, prior to a headache..

[Audio] Figure 15.24 Botox Injections for Migraine Headaches Migraine headaches are typically treated with medication, but Botox injections (see Chapter 4) near certain peripheral nerves provide relief for some individuals. The botulinum neurotoxin interferes with synaptic vesicle fusion (see Chapter 3), which in turn prevents effective release of a number of neurochemicals associated with pain..

Plasticity and Recovery (1 of 2). Reactive neuroplasticity The development of new neurons and the growth of axons, dendrites, and new synapses Takes place within days or weeks Experience-dependent neuroplasticity Changes due to learning Depends on growth and strengthening of synapses Logical target of rehabilitation Timeline can span many years.

Plasticity and Recovery (2 of 2). Kennard Principle Recovery from brain damage is related to developmental stage Younger brains reorganize more effectively than older brains Applies to language functions but not all cognitive functions Language recovery is more extensive than other cognitive processes.

[Audio] Figure 15.25 Reorganization Occurs Following Brain Damage The left occipital lobe was surgically removed from the brain of this monkey 83 days after conception. The resulting reorganization can be seen in the differences between the right and left inferior parietal lobule. The boundaries of this gyrus are the intraparietal sulcus (labeled IP in the image) and the lunate sulcus (labeled L). The right-hemisphere inferior parietal lobule is normal. The left-hemisphere inferior parietal lobule appears to be nearly twice normal size, extending nearly to the back of the brain..

Cognitive Reserve. Some people are less impacted by brain injury or neurodegenerative processes than others Brain size, number of synapses Coping with damage by using cognitive networks in more flexible ways Behavioral outcomes do not always correlate with extent of brain damage Variables linked to cognitive reserve IQ Educational and occupational status Engagement in enriching leisure activities.

Rehabilitation for Neurocognitive Disorders. Rehabilitation means “to restore to good health” Three factors to address Changes to cognitive abilities Emotional changes Physical correlates Methods for improving cognitive function Cognitive (top down) approach Functional (specific tasks) approach Virtual reality (VR) therapy Patients participate without expensive staff “Wii-hab”.

[Audio] Figure 15.26 "Wii-hab" The use of commercial motion-sensing gaming systems allows people to augment their rehabilitation programs and have fun at the same time. This senior takes her tennis game very seriously..