Neurobiology of Addiction_Dr Weiss.pdf - Bellwood Health Services

What drives human behaviour?© 2012 Mark Weiss MD

© 2012 Mark Weiss MD

EatHungerFightSleepFatigueFearFlightLustSex• Brain is wired to engage us in behaviours that promote survival• Feelings drive behaviour© 2012 Mark Weiss MD

How does the brain determine theeffectiveness of survival behaviours?© 2012 Mark Weiss MD

© 2012 Mark Weiss MD

Brain needs a way of measuring how effective ourbehaviours are at meeting our needs.ChocolateCakeRewardLevelCauliflower© 2012 Mark Weiss MD

Evaluating BehavioursMotivationMemoryBehaviourRewardThermometerEvaluation• Compares• Assigns value© 2012 Mark Weiss MD

Evaluating Behaviours (Cont’d)Behaviour Reward Memory• Nucleus• Accumbens• Ventral TegmentalArea (VTA)• Amygdala• HippocampusEvaluation© 2012 Mark Weiss MDPrefrontalCortex

© 2012 Mark Weiss MD

© 2012 Mark Weiss MD

Reward Salience SurvivalHierarchyChocolateCakeCauliflower© 2012 Mark Weiss MD

Reward Salience SurvivalHierarchyRegent Park Vs. Forest Hill© 2012 Mark Weiss MD

Example• Johnny is 4 years old• He wants a cookieScenario ADismissive ResponseScenario BValidating Response© 2012 Mark Weiss MD

Example (Cont’d)• Dismissive Response:– Shut down feelings– Limited learning responses to manage feelingsother than acting on them• Validating Response:– Feelings are important– Flexible responses to feelings– I have choices© 2012 Mark Weiss MD

Reward HierarchyShut downemotionsLoveHugsColouringTVToysDinner© 2012 Mark Weiss MD

Dismissive Response• Delaying satisfaction• Dismissive responses lead to poor selfesteem• If I don’t feel good about myself all I wantto do is feel or not feel© 2012 Mark Weiss MD

Summary• Evaluate experiences– Measuring the reward• Develops hierarchy of reward salience for behaviours• Dismissive response to feelings– Shutting down emotionally as high reward salient behaviour– Inability to delay satisfaction• Validating responses to feelings lead us to experiencefeelings and develop flexible responses– Ability to delay satisfaction© 2012 Mark Weiss MD

Nine – Part ChartPredisposingSocialFactorsAdaptationConsequencesPsychologicalPhysical© 2012 Mark Weiss MD

Psychosocial + Opportunity• Johnny is 14 years old• Undiagnosed ADHD• 16 year old brother is physically andmentally challenged• Both parents work and are done working at6:00 pm• Both parents stressed© 2012 Mark Weiss MD

Genetic Vs. Nurture• Strong concrete in soft soil• Mediocre strength concretein strong soil• Soft concrete in soft soilSoil = NurtureConcrete = geneticsGenetics + Psychosocial + opportunity = Addiction© 2012 Mark Weiss MD

Blame vs. Accountability• Addiction is not your fault.• It is your responsibility !© 2012 Mark Weiss MD

Neurobiology of Addiction• Addiction = disruption of the mechanism bywhich we learn to determine what rewards weneed to surviveAddictiveReward Salienceof Behaviours forSurvival LevelHealthyBehaviours© 2012 Mark Weiss MD

Evaluating Behaviours (Cont’d)Behaviour Reward Memory• Nucleus• Accumbens• Ventral TegmentalArea (VTA)• Amygdala• HippocampusEvaluation© 2012 Mark Weiss MDPrefrontalCortex

Neurobiology of Addiction• Picture of Limbic system© 2012 Mark Weiss MD

© 2012 Mark Weiss MD

WithdrawBrain ChemicalsstimulusElectrical or Druglever© 2012 Mark Weiss MD

© 2012 Mark Weiss MD

© 2012 Mark Weiss MD

NAVTNA = NucleusAccumbensVT = VentralTesmental© 2012 Mark Weiss MD

© 2012 Mark Weiss MD

CauliflowerChocolateCakeMorphineCocaineDopamine© 2012 Mark Weiss MD

Tolerance% ofChange inDopamineTime (Hours)© 2012 Mark Weiss MD

Hedonic ToneHedonic ToneExerciseFoodSex© 2012 Mark Weiss MD

Hedonic ToneHedonic Tone ResetBefore AddictionIn addictionExercise Food SexMorphineCocaine© 2012 Mark Weiss MD

Do This !Simplified ExplanationBehaviourRewardSalienceDrugsDopamineFoodSexPrimal Brain© 2012 Mark Weiss MD

© 2012 Mark Weiss MD

Do This !Simplified ExplanationCortex =Executive Brain• Planning• Evaluation• ChoiceBehaviourDrugsDopamineRewardSalienceFoodPrimal BrainSex© 2012 Mark Weiss MD

• Social upbringing• ?• Genetics• ADHDBehaviourDon’t DoDo ThisYes this feels goodbut something elseis important for his? ? ?DopamineEarly Drug AbusePrimal Brain© 2012 Mark Weiss MD

Hypo FrontalityBehaviourDo ThisDopamineLate Drug AbusePrimal Brain© 2012 Mark Weiss MD

Emotional MemoryAmygdalaHippocampusPlanning Decision Making ChoicesBehaviourOpiatesNAVTA© 2012 Mark Weiss MDDopamine?????? InformationBiological Salience/

© 2012 Mark Weiss MD

Pictures of Damage© 2012 Mark Weiss MD

© 2012 Mark Weiss MD

Hypo FrontalityBehaviourDo ThisDopamineLate Drug AbusePrimal Brain© 2012 Mark Weiss MD

Implications• Early treatment/ recovery• Inherit an executive brain• Why barriers• Time© 2012 Mark Weiss MD

Implications (Cont’d)• Meaning and Values = What is important tomeRisk ofAddiction Contentment Serenity Relationships Fun Resilience Coping Skills© 2012 Mark Weiss MD

Implications (Cont’d)Risk ofAddiction Contentment Serenity Relationships Fun Resilience Coping Skills© 2012 Mark Weiss MD

Implications (Cont’d)• Recovery is about a life well lived• What it means:– Building context and relevance to yourexperiences– Behaviour A is rewarding. However,behaviour B is more rewarding on < have tochoose© 2012 Mark Weiss MD

I Would Like MoreInformationMark Weiss, MDMedical DirectorBellwood Health Services Inc.www.bellwood.ca416-495-0926, toll free 1-800-387-6198mweiss@bellwood.ca© 2012 Mark Weiss MD