Psyc4130 1nd Edition Lecture 36 Outline of Last Lecture I VTA II Hedonics Models III Self Medication IV Brain Plasticity V Who Becomes Addicted VI PFC Underdevelopment VII Tolerance VIII Withdrawal IX Withdrawal and Neg Reinforcement Outline of Current Lecture I SSRI Synaptic Action II SSRI Side Effects III Serotonin Syndrome IV SSRIs and Pediatric Psychiatry V Trazodone Desyrel VI SNRIs VII Bupropion Wellbutrin VIII Efficacy of Antidepressants IX Do Happy Pills Work X Addiction Withdrawal Neg Reinforcement XI Review Current Lecture SSRI Synaptic Action More recent research has demonstrated that augmenting 5 HT1A receptor activity leads to the therapeutic effects of SSRIs Many of the side effects are mediated through enhanced 5 HT2 receptor activity SSRI Side Effects Less toxic dangerous severe Serotonin Syndrome Rare but toxic Disorientation Confusion w Possible Mania Severe Psychomotor Agitation These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute Severely Elevated Blood Pressure Fever hyperthermia Cold Sweats Diaphoresis Diarrhea Visual Disturbances Coma and Possible death SSRIs and Pediatric Psychiatry Some mid 2000s reports indicated an increase risk of suicide ideation and behavior in youth taking SSRIs Due to media attention and FDA warnings prescriptions dropped precipitously o Physicians less likely to prescribe drug Since then there is evidence that suicide rates among young people in the US are increasing Trazodone Desyrel A modified SSRI Blocks 5 HT RI i e blocks 5 HT transporter o antagonist Blocks 5 HT2A receptors postsynaptically minimizes side effects SNRIs Block reuptake of NE and 5 HT with fewer non specific actions than TCAs Venlafaxine Effexor o RI of NE and 5 HT Duloxetine Cymbalta o RI of all three monoamines Bupropion Wellbutrin Atypical Antidepressant o Dopamine reuptake inhibitor selective like an SDRI Does not significantly influence 5 HT activity Mechanisms of Action DRI Partial NERI Antagonizes nAChRs o Smoking cessation antagonization Equal antidepressant efficacy vs SSRIs May actually increase libido therefore bupropion may be used in conjunction with SSRIs Has psychostimulant properties but not addictive like cocaine or amphetamines due to slow absorption and reduced transporter occupancy Side Effects Restlessness Agitation Motor Tics Tremors decrease Appetite and Weight loss GI Disturbance Seizures Rare Contraindicated in patients with panic disorder epilepsy or other seizure disorders Efficacy of Antidepressants Variable o Relatively week overall clinical efficacy Up to half of all patients do not respond to initial pharmacotherapy Some of these however will respond to a different antidepressant Among responders some experience decreased efficacy Poop Out over time o Drug becomes less and less effective over time Do Happy Pills Work Kirsch and Sapirstein 1998 analyzed results from 19 clinical studies and estimated that the vast majority of the effects of prescription antidepressants owed to classic placebo expectancy effects They suggested that most of the remaining effects owed to active placebo effects o Placebo effects increasing serotonin transmission gets effects but not exact effects that would should help aka bodily change makes you think its working Addiction Withdrawal Neg Reinforcement chapter 18 Relapsing into drug abuse to keep negative withdrawal effects at bay Aversive withdrawal make it goes away reuse Tends to maintain reinstatement relapse Relapse reinstatement can be primed or cued environmental context GABA activity in the dorsal ACC appears to intensify drug craving o Triggers response in reinforcement apparatus in the brain The dorsal ACC has excitatory connection to the VTA Administration of a GABA agonist therefore decreases reinstatement by reducing VTA activity On the other hand activity in the vmPFC inversely relates to relapse reinstatement Chronic use of cocaine is associated with 5 11 loss of grey matter in various regions of the PFC Other researchers have substantiated losses of PFC and limbic cortex gray matter in chronic users of cocaine and methamphetamine Thompson et al 2004 Ersch et al 2011 and a decrease in mPFC activation in heavy smokers and pathological gamblers de Reuiter et al 2011 Addiction BAD for PFC Stress can both predispose substance abuse addiction and TRIGGER relapse reinstatement Maternal deprivation rats take mom away from babies for an hour a day test when they are adults stress anxiety Social defeat induce a naturalist type of stress in animals Know CRH for final o Only hormonal pathway fight or flight response o Administering CRH can reinstate drug taking behavior Partial agonists can help reduce cravings Buprenex partial agonist working as an antagonist Review Schizo and depression know transmitter hypothesis how research led to a revision o Dopamine hypothesis original one and how it was revised 50 100 questions multiple choice 70 on newer stuff since emotions AIS CAH sex hormones mix match
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