Published on February 18, 2008
Psychopathology and Emotional Memory: Psychopathology and Emotional Memory Psychopathology: Psychopathology Disorders characterized by abnormal emotions, cognitions, behavior Most often treated by psychiatrists, but also clinical psychologists and general practitioners (e.g., family doctors) High incidence and prevalence in the population Disorders: Disorders Depression Anxiety Generalized Anxiety Disorder (GAD) Obsessive Compulsive Disorder (OCD) Panic Disorder (PD) Posttraumatic Stress Disorder (PTSD) What’s emotion & memory got to do with it?: What’s emotion & memory got to do with it? In most forms of psychopathology, abnormal emotion, memory, or both are listed as symptoms Stress or negative emotions are often a trigger for the onset of various forms of psychopathology In cases such as PTSD, these are the primary symptoms How are the disorders classified?: How are the disorders classified? Traditionally, psychiatry is the only area of medicine in which the practitioner does not look at the organ being treated, but this is changing. The Diagnostic and Statistical Manual of Mental Disorders IV (DSM IV) is the standard classification system of mental disorders Diagnostic classification: depression or anxiety Diagnostic criteria: symptom, duration descriptions Descriptive test: diagnostic features, subtypes, culture, age, and gender features, etc. DSM Classification: DSM Classification Multiaxial Classification Axis I: depression, anxiety, schizophrenia, etc. Axis II: Personality disorders/mental retardation Axis III: General medical conditions Axis IV: Psychosocial & environmental problems Axis V: Level of adaptive functioning Why classify disorders?: Why classify disorders? “What’s the use of their having names” the Gnat said, “If they won’t answer to them?” “No use to them,” said Alice, “but it’s useful to the people that name them, I suppose.” Alice in Wonderland Why Classify? One purpose of science Description allows communication Provides homogeneous groups to study Enables development of testable hypotheses Critique of DSM Classification: Critique of DSM Classification Exhaustive nature of DSM has led some to lament that “everything is a disorder” depressive episode dependent personality disorder Not all DSM diagnoses are treated as mental disorder on their own The large number of symptoms included allows physicians and researchers to better categorize patients into appropriate groups depression with dependent personality Major Depression: Major Depression Presence of major depressive episode: Depressed mood for at least 2 week period including most of the following: Diminished interest in activities Change of more than 5% of body weight Insomnia or hypersomnia Psychomotor agitation Fatigue Feelings of worthlessness Diminished ability to think or indecisiveness Recurrent thoughts of death Depression, continued: Depression, continued Depressive episode must not be in response to specific incident or if it is, the episode must last longer than 2 weeks bereavement postpartum depression Must be no history of manic episodes Biological Bases of Depression: Biological Bases of Depression Heritability has been established in twin studies and family studies Depression is amenable to physical treatments including Pharmacological treatments MAO inhibitors (e.g. iproniazid) Serotonin reuptake inhibitors (e.g. Prozac) Electroconvulsive shock therapy (ECS) only in the most severe, suicidal cases Monoamine Hypothesis of Depression: Monoamine Hypothesis of Depression Depression results from reduced activity of brain monoamines norepinephrine, serotonin, dopamine Reserpine depletes monoamines--> depression Antidepressant meds increase either NE or serotonin Usually via blockade of monoamine reuptake Prozac = selective serotonin reuptake inhibitor (SSRI) Anxiety Disorders: Anxiety Disorders Generalized Anxiety Disorder Panic Disorder Posttraumatic Stress Disorder Slide16: Anxiety may involve: Underactive GABA system in neural circuit including the amygdala and prefrontal cortex Reduced levels of benzodiazepine receptors? diazepam (Valium) is a benzo receptor agonist Reduced serotonin activity in brain The serotonin agonist fluoxetine (Prozac) can be be used to treat anxiety Biological Bases of Anxiety Disorders Slide17: A Host of Anxiety Drugs, Begat by Valium From NYTimes.com: Published: February 22, 2005 Among famous inventors, Leo H. Sternbach may not immediately leap to mind. But this May in Akron, Ohio, Dr. Sternbach, who is 96, will be inducted into the National Inventors Hall of Fame. He holds more than 240 patents, but perhaps his most famous invention, in collaboration with colleagues, is a chemical compound called diazepam, better known by its brand name, Valium. One of the earliest benzodiazepines, Valium was approved by the Food and Drug Administration in 1963 as a treatment for anxiety, and it would become not only the country's best-selling drug, but an American cultural icon. Referred to knowingly in Woody Allen movies, enshrined as "Mother's Little Helper" in the Rolling Stones song, condemned as poisonous in best-selling books, Valium reached the height of its popularity in 1978, a year when Americans consumed 2.3 billion of the little yellow pills. But by the 1980's its reputation for creating abuse and withdrawal problems was well known, and the new selective serotonin reuptake inhibitors like Prozac were widely considered better treatments for anxiety and panic disorders. Still, the benzodiazepines - there are now more than a dozen others available besides Valium - never disappeared. They are still widely prescribed and, in the view of many doctors, extremely effective in treating not only anxiety and panic disorder, but bipolar illness, insomnia, catatonia and alcohol and drug withdrawal. Generalized Anxiety Disorder: Generalized Anxiety Disorder At least 6 months of anxiety not linked to a single object or situation Plus 3 or more of the following: Restlessness Get tired easily Concentration problems Irritability Muscle tension Problems falling or staying asleep Not associated w/ other disorder (e.g., substance abuse, general medical disorder) Panic Disorder: Panic Disorder Unexpected and recurrent panic attacks (discrete period of overwhelming fear and anxiety) At least one of the following: Persistent concerns of having panic attack Concerns about meaning or consequences of panic attacks (“going crazy”, heart attack) Significant behavioral changes related to panic attacks (reduced social function) Panic Disorder Characteristics: Panic Disorder Characteristics 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 Biological Bases of PD: 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 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 Posttraumatic Stress Disorder: Posttraumatic Stress Disorder Anxiety disorder that develops after event involving intense fear, horror, or helplessness Symptoms must include 1 of the following: Distressing recollections of event Recurring dreams of event Reliving the event Stress in response to any aspect of event Physiological response to any aspect of event Impairment in areas of function (work, social life) PTSD Statistics: PTSD Statistics It is estimated that of those exposed to traumatic events, 15% will develop PTSD 40% of those recover in a year (6% last > 1 yr) Originally documented in combat veterans, initially called “shell-shock” Documented in response to physical and sexual abuse, victims of violent crime, disasters, motor vehicle accidents Co-morbidity: Co-morbidity The presence of more than one disorder Patients often present with some combination of these disorders Someone with ‘pure’ depression is rare, more often, they have some degree of anxiety, perhaps psychotic behavior Problematic for research (as well as for the individuals) Mood Dependent Memory: Mood Dependent Memory Slide26: 1931 - Accompanied by Albert Einstein, Charlie Chaplin arrives at premiere of his new picture, “City Lights“, at the Los Angeles Theatre. Mood Dependent Memory: Mood Dependent Memory Subjects produced a list of pleasant & unpleasant events from their childhood Several days later, were hypnotized and put into either happy or sad mood # Memories Retrieved adapted from Bower (1981) Emotional Memory Studies in Patient Groups: Emotional Memory Studies in Patient Groups There is a large body of research on memory and emotion in psychiatric patient groups Depression leads to decreased memory performance, but a ‘negativity bias’ in recall of laboratory and autobiographical memories increased memory for negative stimuli over neutral/positive stimuli Emotional Memory in Psychopathology: Emotional Memory in Psychopathology Anxiety disorders No specific memory effects in GAD, though they show heightened attention to negative stimuli Panic patients do show increased retrieval of threat-related information PTSD patients show decreased attention and memory performance but spared recall of trauma-related cues Slide30: Previous work suggested differential memory processing of emotional information in depression & anxiety Anxious are more likely to show more pre-attentive processing to threat, enhancing implicit memory (priming) Depressed are more likely to ruminate on negative material, enhancing explicit memory (free recall) Slide31: anxiety indices Groups that share the same superscript letter (a, b, or c) are not statistically different. Groups that do not share letter are statistically different on that measure (p < 0.05) Methods: Methods Memory for 3 word categories anxiety-relevant: embarrassed, cancer depression-relevant: misery, despair positive: paradise, adorable categorized neutral: cleaning, carpet (household items/activities) Implicit memory Explicit memory 12 words of each category (not presented to subject in implicit task) presented for 7 seconds each Surprise free recall 2 minutes later Slide33: + misery + cleaning Suprathreshold Priming 800 ms 7 sec 800 ms 7 sec Respond ‘word’ or ‘nonword’ Quicker response to primed than unprimed category words is index of priming Slide34: + misery jdtuyr + SUBthreshold Priming 800 ms 14 ms 800 ms 800 ms + cleaning + misery Lexical Decision Task + despair + doorbell + traib primed neutral primed depression unprimed depression unprimed neutral non-word 5 min later Respond ‘word’ or ‘nonword’ cleaning dcvtlr 14 ms 800 ms Slide35: Implicit Memory Performance Priming effect = (latencies for unprimed) – (latencies for primed); positive values = more priming, quicker response to prime Slide36: Explicit Memory Performance Slide37: Across all subjects, mood measures were negatively correlated with memory for positive words & depression measures were positively correlated with memory for depression words Anxiety vs. Depression: Anxiety vs. Depression There was no evidence of emotional memory bias in anxiety disorder patients anxiety only affects attention? Depression results in a bias in automatic (implicit) and controlled (recall) performance mood-dependent memory? rumination on depression topics primes increased memory for depression-relevant stimuli Cognitive effects of anxiety vs. depression: Cognitive effects of anxiety vs. depression “...a primary function of anxiety is to detect and deal with threat, whereas a primary function of depression is to detach oneself from inappropriate, unattainable goals and to reflect on past events in an attempt to revise those goals.” PTSD Vulnerability & Memory: PTSD Vulnerability & Memory Research has shown PTSD patients have poor memory, though may have spared trauma-related memories Also, PTSD patients have smaller hippocampi than non-PTSD patients matched for experience, age, gender Which came first? Slide41: OR Background : Background HC is necessary for declarative memory formation Exposure to stress can damage the HC Are differences in HC volume a consequence of trauma, or a pre-existing trait that predisposes people to pathological reactions to a traumatic event? Slide43: Subjects: 50 male twin pairs; one of each pair served in Vietnam war, one did not. 17 developed PTSD; 23 did not Slide44: Possible Scenarios for Influence of Traumatic Stress on HC (or vice versa) Slide45: Twins of those who developed PTSD had lower HC volume than those w/o PTSD regardless of whether they had been exposed to trauma = < = Slide46: High PTSD severity is associated with lower HC volume, both in the combat-exposed twin and the one w/o combat exposure. PTSD & HC Summary: PTSD & HC Summary A smaller hippocampus may be a predisposing factor toward, rather than a consequence of, PTSD Rodents w/HC lesions show stronger conditioned fear: more rapid acquisition of avoidance response and more fear behavior following acquisition PTSD & HC Summary: PTSD & HC Summary HC is also involved in regulation of stress hormone responses (negative feedback of HPA axis) Monkeys w/small HC respond to stressful rearing conditions w/increased cortisol Small HC volume may predispose individuals to acquire stronger conditioned emotional responses or stronger hormonal responses when exposed to trauma Conclusions: Conclusions Mental disorders associated with emotion and/or memory may or may not be associated with altered memory performance Depression is associated with a negative bias in memory, perhaps explained by mood dependent memory Conclusions: Conclusions GAD is not associated with memory deficits or bias, perhaps only affects attention PTSD may be due to smaller hippocampi, which predisposes toward development of the disorder Future work will find more neural and cognitive abnormalities associated with these disorders and (hopefully) better ways to treat them.