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Bryan Kolb & Ian Q. Whishaw’s. Fundamentals of Human Neuropsychology, Sixth Edition Chapter 27 Lecture PPT. Prepared by Gina Mollet, Adams State College. Psychiatric and Related Disorders. Portrait: Losing Touch with Reality. Mrs. T. Symptoms of schizophrenia beginning at age 16
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Bryan Kolb & Ian Q. Whishaw’s Fundamentals of Human Neuropsychology, Sixth Edition Chapter 27 Lecture PPT Prepared by Gina Mollet, Adams State College
Portrait: Losing Touch with Reality • Mrs. T. • Symptoms of schizophrenia beginning at age 16 • Began with self-consciousness and progressed to delusions and hallucinations • Hallucinations led to bizarre and dangerous behavior • PET scans of schizophrenia indicate abnormal blood flow in the prefrontal cortex
The Brain and Behavior • The mind-body problem • Dualists • Monists • Psychiatric or behavioral disorders have a biological, anatomical, or genetic basis
Schizophrenia • DSM-IV R • Delusions or beliefs that distort reality • Hallucinations • Disorganized speech, senseless rhyming • Disorganized, agitated behavior • Blunted emotions, loss of interest and drive
Structural Abnormalities in Schizophrenic Brains • Less than average weight • Enlarged ventricles • Reduction in the number of neurons in the prefrontal cortex • Abnormal cellular structure in the prefrontal cortex and hippocampus • Hypofrontality during card sorting
Biochemical Abnormalities in Schizophrenic Brains • Dopaminergic function • Anti-psychotics • Act on the dopamine synapse • Glutamate • GABA
Types of Schizophrenia • Type I: Acute Schizophrenia • Positive symptoms • More responsive to neuroleptics (anti-psychotics) • Type II: Chronic Schizophrenia • Negative symptoms • Structural abnormalities in the brain
Schizophrenia As a Disorder of Development • Develops during late adolescence • Slow emergence of brain abnormalities • Combination of genetics and environment • No single gene • More likely to have experienced a combination of adverse events
Neuropsychological Assessment • Poor performance on long-term verbal and nonverbal memory • Poor frontal-lobe functioning • May not perform well on any test
Mood Disorders • Clinical Depression • Prolonged feelings of worthlessness and guilt • Behavioral slowing • Disrupted eating and sleeping • Mania • Excessive euphoria • Hyperactivity • Bipolar disorder • Periods of depression and mania
Neurochemical Aspects of Depression • Reduction of monoamines • Brain-derived neurotrophic factors (BDNF) • Downregulated by stress • May affect functioning of monoamine synapses • Hypothalamic-Adrenal system (HPA-axis) • Oversecretion of cortisol; chronic stress • Widespread influence on cerebral functioning • Kills granule cells in the hippocampus
Neurochemical Aspects of Depression • Fluoxetine • SSRI • Stimulates BDNF and neurogenesis in the hippocampus
Blood Flow and Metabolic Abnormalities in Depression • Decreased activity in: • Dorsolateral and medial prefrontal regions • Reduced memory and attention • Increased activity in: • Orbital regions • An attempt to inhibit amygdala activity • An attempt to break persistent negative thoughts • Amygdala • May increase HPA-axis activity • Medial thalamus
Blood Flow and Metabolic Abnormalities in Depression • Sleep-cycle • May be altered due to lowered serotonin levels • Thyroid-hormone • Decrease in production may influence mood
Neurobiological Aspects of Bipolar Disorder • Decrease in gray matter in the temporal lobe and cerebellum • Decrease correlates with number of episodes • Sensitization Model • Bipolar patients are sensitive to stress and drugs • Episodes of mood disorder change the brain
Snapshot: Cortical Metabolic and Anatomical Abnormalities in Mood Disorders • Drevets and colleagues • PET images of unipolar and bipolar patients • 12% decrease in blood flow to the subgenual area • Bipolars exhibit an increase in blood flow during the manic phase • MRI images of unipolar and bipolar patients • Reduction in gray matter volume in the left subgenual area
Neurobiological Aspects of Bipolar Disorder • Sensitization Model • Genetically predisposed individuals may be more sensitive • There is a link between psychomotor-stimulants and mania • Bipolars are at high risk for drug abuse and may be especially sensitive to the effects
Vitamins, Minerals, and Food • Kaplan and colleagues • Mood symptoms may be related to: • Inborn errors in metabolism • Alterations in gene expression • Epigenetic alterations in genes • Long-latency effects of nutritional abnormalities
Psychiatric Symptoms of Cerebral Vascular Disease • Post-stroke patients • 25-50% experience depression • About 25% experience generalized anxiety disorder • Catastrophic reactions • 11-50% experience pathological affect
Psychosurgery • Destruction of a region of the brain to alleviate psychiatric symptoms • Neurosurgery • Brain surgery intended to repair damage to alleviate symptoms • Egas Moniz • Prefrontal lobotomy
Psychosurgery • Modern Psychosurgery • 13 targets • Smaller lesions • Rarely performed • Does not replace abnormal activity with normal activity
Motor Disorders • Hyperkinetic • Increase motor activity • Hypokinetic • Loss of movement
Hyperkinetic Disorders • Huntington’s chorea • Genetic disorder • Intellectual deterioration and abnormal movements • Begins as a reduction of activity and a restriction of interest • Involuntary movements begin about a year later
Hyperkinetic Disorders • Huntington’s chorea • Movements • Entail whole limbs • Irregular, no pattern • Affect head, face, trunk and limbs • Behavioral Symptoms • Personality changes • Cognitive impairments • Anxiety, depression, mania, and schizophrenic-like psychoses
Hyperkinetic Disorders • Huntington’s chorea • Brain abnormalities • Shrinkage of the cortex • Atrophy of the basal ganglia • Imbalance among the various neurotransmitter systems • Death of GABA and ACh neurons in the basal ganglia • Poor performance on memory and frontal-lobe tests
Tourette’s Syndrome • Three stages • 1. Multiple tics • 2. Inarticulate cries are added to the tics • 3. Articulate words • Echolalia: Repeating what others say • Coprolalia: Obscene or lewd speech • Age of onset: 2-15 • Not associated with neuroses, psychoses, or other disorders
Tourette’s Syndrome • Subcortical origin • Small cells in the basal ganglia • Treatment • Antidopaminergic drugs • Norepinephrine receptor agonists • Abnormalities in cognitive functions supported by the right hemisphere
Hypokinetic Disorders • Parkinson’s Disease • Degeneration of the substantia nigra • Loss of dopamine • Variety of symptoms that vary from patient to patient • Symptoms resemble changes in motor activity that occur with age
Hypokinetic Disorders • Parkinson’s Disease • Rigidity • Tremor • Akinesia • Postural disturbances
Hypokinetic Disorders • Parkinson’s Disease: Positive Symptoms • Resting tremor • Muscular rigidity • Cogwheel rigidity • Involuntary movements • Akathesia • Cruel restlessness • Oculogyric crisis • Involuntary turns of the head and eyes to the side
Hypokinetic Disorders • Parkinson’s Disease: Negative Symptoms • Disorders of posture • Disorder of fixation • Disorder of equilibrium • Disorders of righting • Disorders of locomotion • Festination • Disorders of speech • Akinesia
Hypokinetic Disorders • Progression of Parkinsonism • Begins with tremors in the hand • Face becomes masklike and movement slows • 10-20 years of progression • On-again-off-again quality
Causes of Parkinsonism • Idiopathic • Familial • Part of the aging process • Viral origin • Postencephalitic • Occurs after encephalitis
Causes of Parkinsonism • Drug Induced • Ingestion of major tranquilizers • Contaminant of synthetic heroin (MPTP) • Environmental toxins • Depletion of dopamine
Treatment of Parkinson’s Disease • Physical therapy • Pharmacological therapy • Increase dopamine function • Block cholinergic system • Stem-cell research • Deep brain stimulation (DBS)
Psychological Aspects of Parkinson’s Disease • Cognitive functions • Generalized behavior slowing • Show symptoms similar to individuals with frontal lobe or basal ganglia lesions • Impaired on the WAIS
Dementia • DSM-IV-R • Memory and other cognitive deficits • Impairment in social and occupational functioning • Degenerative dementias • Intrinsic to the nervous system • Affects the CNS selectively • Nondegenerative dementias • Diverse etiologies
Dementia • Alzheimer’s disease • Most prevalent form of dementia • Neuritic Plaques • Found in the cortex • Positively correlated with cognitive decline • Amyloid surrounded by degenerative cellular fragments • Paired Helical Filaments • Found in the cortex and hippocampus