ch.18 anxiety disorder, autistic disorder, and stress disorders

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Copyright 2001 by Allyn & Bacon Carlson (7e) PowerPoint Lecture Outline Chapter 18: Anxiety Disorder, Autistic Disorder and Stress Disorders ltimedia product and its contents are protected under copyright he following are prohibited by law: blic performance or display, including transmission of any image over a network; ation of any derivative work, including extraction, in whole or in part, of any images; ntal, lease, or lending of the program.

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Page 1: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Carlson (7e) PowerPoint Lecture Outline Chapter 18: Anxiety Disorder, Autistic Disorder and Stress

Disorders

This multimedia product and its contents are protected under copyright law. The following are prohibited by law:•any public performance or display, including transmission of any image over a network;•preparation of any derivative work, including extraction, in whole or in part, of any images;•any rental, lease, or lending of the program.

Page 2: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Anxiety Disorders

The common element of the anxiety disorders is the presence of unrealistic, unfounded anxiety

Panic disorder involves episodes of intense anxiety

Obsessive-compulsive (O-C) disorder refers to anxiety associated with recurrent thoughts and actions

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Page 3: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Panic Disorder (PD)

Physical symptoms of panic disorder include Shortness of breath and irregular heartbeat Dizziness and feelings of unreality

Episodes of panic occur in 1-2 % of population Panic disorder has an early onset (rare after age 35)

Symptoms of PD are similar across cultures Anticipatory anxiety about future panic attacks

leads to Agoraphobia: fear of panic attack in public places

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Page 4: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Biological Bases of PD

MZ twins have a higher concordance rate for panic disorder than do DZ twins

Panic Disorder is more likely in families of patients with the disorder Family pattern of panic disorder suggests that PD is caused by a

single dominant gene Panic attacks can be triggered by events that activate the

autonomic nervous system: Lactic acid injections Caffeine consumption Breathing air containing high levels of carbon dioxide

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Page 5: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Anxiety may involve Reduced levels of benzodiazepine receptors and

lowered sensitivity to an unknown endogenous benzodiazepine agonist

CCK-4, a peptide that induces panic attack in PD patients, but not in normal subjects

Reduced serotonin activity in brain The serotonin agonist fluoxetine can be be used to treat PD Yet, the tryptophan depletion procedure, which reinstates

depression, does not produce anxiety attacks in PD patients Altered activity within the frontal cortex

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Page 6: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Obsessive-Compulsive Disorder

Obsessions are recurrent thoughts Compulsions are recurrent behaviors

The incidence of O-C disorder (OCD) is 1-2 percent OCD begins in young adulthood Symptoms of OCD are similar across differing

cultures OCD can greatly limit life options

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Page 7: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Compulsions

The four categories of compulsions include Counting (“am I missing a dollar?”) Cleaning (hands, house) Checking (“Did I turn the stove off?”) Avoidance (e.g. dirt)

Compulsions may represent exaggerations of normal species-typical behaviors aimed at keeping an animal clean and away from danger

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Page 8: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Brain Activity and OCD

OCD is linked with a neurological syndrome Tourette’s syndrome involves

Muscular/vocal tics, facial grimaces, word repetition

OCD may involve damage to basal ganglia, cingulate gyrus, and prefrontal cortex OCD is associated with neurological syndromes that involve

damage to the basal ganglia (Huntington’s chorea) OCD is associated with increased activity within the frontal

lobes Drug therapy for OCD reduces frontal lobe activity Surgical transection of the subcortical frontal lobe leads to

improvement in OCD (as did a gunshot wound to the head)18.8

Page 9: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Pharmacotherapy of OCD

Drug therapy for OCD involves drugs that are agonists for brain serotonin systems Blockade of 5-HT reuptake improves OCD symptoms

Clomipramine Fluoxetine Fluvoxamine

OCD drugs require weeks to relieve OCD symptoms Antagonism of 5-HT receptors worsens OCD, whereas the

tryptophan-depletion procedure does not 5-HT agonism appears to reduce intensity of the species-

typical behaviors (e.g. washing)

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Page 10: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Serotonin and Compulsions

Human compulsions Trichtillomania refers to compulsive hair pulling Onychophagia refers to compulsive nail biting Both compulsions are reduced by ingestion of

clomipramine (a serotonin agonist) Dog compulsions

Acral lick dermatitis refers to compulsive licking by a dog of a body part; ALD is treated by administration of clomipramine

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Page 11: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Autism

Autism involves self-absorption Specific features of autism include

Impaired social relations with others An inability to communicate

Literal interpretation of speech Impaired imaginative ability Stereotyped movements

Incidence of autism is 4/10,000 Males are 3 times more likely to develop autism

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Page 12: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Biological Bases of Autism

Heritability of autism MZ twins exhibit a 96% concordance rate for autism, while that of

DZ twins is comparable to that of normal siblings 2-3% of the siblings of autistic children are themselves autistic

Autism is associated with neurological disorders: Phenylketonuria (PKU) Tourette’s syndrome

Factors that impair development lead to autism: Rubella, hydroencephalus Drugs such as thalidomide (exposure during prenatal days 20-24

impairs development of the brain stem)

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Page 13: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Stress

Aversive stimuli can elicit emotional responses: Behavioral component: “Fight or Flight” response Autonomic component: Sympathetic activation Endocrine: secretion of epinephrine, norepinephrine

Physiological reactions to chronic aversive stimuli/situations can be damaging Stressors: the aversive stimuli we encounter Stress Response: our reaction to stressors

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Page 14: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Hormone Secretion during Stress

Stressors evoke activity in the sympathetic nervous system

Adrenal glands release Epinephrine: biases energy flow to muscles, blood flow from

heart, and increases blood pressure Norepinephrine: is released in brain during stress Glucocorticoids: break down protein and fats to glucose,

increase blood flow, and stimulate behavioral responsiveness Cortisol secretion is controlled by a releasing factor (CRF)

produced by the PVN PVN CRF --> pituitary ACTH --> adrenals: secrete glucocorticoids CRF may act as a “stress” transmitter

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Page 15: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Glucocorticoid Secretion

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Page 16: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Chronic Exposure to Stressors

Chronic stress is damaging to health Air traffic controllers are more likely to develop

High blood pressure Ulcers and diabetes

Chronic secretion of glucocorticoids leads to: Increased blood pressure (--> stroke, heart attacks) Loss of neurons in brain (e.g. hippocampal field CA1) Suppression of the immune system (--> illness) Suppression of the inflammatory system (delays wound

healing)

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Page 17: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Posttraumatic Stress Disorder

Posttraumatic Stress Disorder (PTSD): Acute exposure to very intense stressors (air

disasters, war, assault) can have delayed stress effects

Dreams, recall of trauma event Flashback episodes of event Intense distress

PTSD symptoms include: Diminished social interests Suppressed emotional feelings Feelings of detachment

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Page 18: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Predisposing Factors for PTSD

Personality variables that predispose to PTSD: Tendency to brood about feelings

Vietnam Veterans study identified four factors that contribute to developing PTSD Family financial difficulty History of drug abuse/dependence History of affective disorders History of childhood behavior problems

PTSD patients exhibit reduced volume of the hippocampus (consistent with toxic action of glucocorticoids on hippocampal cells)

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Page 19: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Coping Responses and Stress

Stress reflects our reaction to stressors Coping implies modifying our responses:

Exerting control over aversive stimuli can reduce stress responses

Weiss study: rats that avoid shock show fewer ulcers

Coping may involve an increase in the level of benzodiazepines in brain (would act via GABAA sites to reduce anxiety)

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Page 20: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Psychoneuroimmunology

Psychoneuroimmunology is the study of the interactions between the immune system and behavior Stress responses can impair the immune system Leading to illness and potential death

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Page 21: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Overview of the Immune System

Immune system acts to destroy foreign organisms (viruses, bacteria, fungi)

Nonspecific reactions: act to destroy organisms or infected cells Inflammatory reaction: damaged cells leak substances that

increase blood flow Phagocytotic white blood cells: destroy damaged cells Cell infection --> interferon secretion (reduces viral

replication) Natural killer cells: detect and destroy infected cells

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Page 22: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Immune Reactions

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Chemically-Mediated Cell-Mediated

Page 23: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Specific Immune Reactions

Specific immune reactions include: Chemically-mediated: immune system produces

antibodies that recognize the antigens present on surface of a foreign cell

B-lymphocytes: produce immunoglobulin antibodies that destroy foreign cells

Cell-mediated: antibodies on exterior of T-lymphocytes detect foreign antigens (viruses)

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Page 24: Ch.18 Anxiety Disorder, Autistic Disorder, and Stress Disorders

Copyright 2001 by Allyn & Bacon

Stress and the Immune Response

Stress increases the likelihood of infectious disease Students are more likely to be ill during exam times Death of a spouse leads to illness of survivor

Explanation: stress releases glucocorticoids that in turn impair the immune system

Supporting Evidence: Bereavement leads to reduced immune response Alzheimer’s caregivers have impaired immune response Inescapable shock in rats reduces T-cells, B-cells and natural

killer cells

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