Lecture 13 - Addiction & Cannabis
What is cannabis?
- Most commonly used illegal drug in the world
- Most controversial
- Comes from cannabis sativa and cannabis indica plant
- Over 80 cannabinoids know
Cannabis administration
- Inhalation (smoking)
- 50% enters lungs, almost all of that enters body
- Reaches brain in about 30 sec
- Peaks 30-60 min, lasts 3-4hrs, subjective state for 12 hrs
- Oral (eating)
- Absorbed from gut slowly
- Onset is 1h
- Peak 2-3hrs
- Larger oral dose needed to have same effect as inhaled
Psychological effects
- Subjective effects (buzz, high)
- Sometimes mood swings to anxiety and/or panic, especially at higher doses
- Effects modulated surroundings
Psychodynamics
- Endogenous cannabinoid system (endocannabinoid; eCB)
- Endogenou ligands; anandamide (AEA) and 2- arachidonoylglycerol (2-AG)
- Two main receptors: CB1 (brain) and CB2 (immune system)
- Anandamide and THC bind to CB1
- 1-AG and CBD bind to both CB1 and CB2
THC: how it works in the brain
- CB1 receptors are located presynaptically on axon terminals
- THC mimic the shape of AEA and works by this mechanism
- Cumulative effect of pathways is euphoric feeling associate with cannabis use
Lecture 14 - Schizophrenia
Schizophrenia
- Psychotic disorder
- Psychosis
- Common disease (1/100), severe consequences
History
- Emil Kraepelin - Dementia praecox
- ‘Madness’ ‘lunacy’
- Dementia praecox
- Edgen Bleuler - schizophrenia - split mind
, Myths
- Violent and dangerous
- Multiple personalities
- See things that aren’t there
Characteristics / symptoms
- Positive: go beyond normal occurring experiences (hallucinations, delusions, paranoia)
- Negative: deficit of absence of normal behaviour (apathy, limited though/speech,
emotional and social withdrawal)
- Apathy: inability to ‘get started’, perform basic day-to-day tasks
- Autism: tendency to keep oneself and lose interest in other ppl or surroundings
- Ambivalence: emotional and social withdrawal
- Anhedonia: indifference to activities that are typically considered to be
pleasurable
- Affective flattening: absence of visible emotions, facial expressions and
emotional inflections in speech
- Cognitive: erratic changes in speech, motor behaviour and emotions (disorganized
speech, inappropriate emotions; reactions)
- Pathognomic: symptom unique to a specific disorder
DSM-5 criteria
- At least one: delusions, hallucinations, disorganized speech
- Diminished level of function
- Long-lasting symptoms
- Not due to drugs or a medical condition
Development
- Usually diagnosed in late adolescence / early adulthood
- Prodromal stage - 1-2 year period where subdues symptoms begin to appear (85% of
ppl)
Development and prognosis
- Complete remission is rare
- Pattern of relapse and recovery
- Prognosis is poorer than most other disorders
- recovery/remission more likely of:
- Good social adjustment prior to onset
- Low proportions of neg symptoms
- Good social supports system for patients
- Symptoms tend to decrease with age
Etiology - genetics
- Clear genetic link (not 100%)
Etiology - prenatal factors
- Virus exposure
- Stress
- Pregnancy delivery complications
Etiology - stress
- Stressful life event, stress and genetics interaction
What is cannabis?
- Most commonly used illegal drug in the world
- Most controversial
- Comes from cannabis sativa and cannabis indica plant
- Over 80 cannabinoids know
Cannabis administration
- Inhalation (smoking)
- 50% enters lungs, almost all of that enters body
- Reaches brain in about 30 sec
- Peaks 30-60 min, lasts 3-4hrs, subjective state for 12 hrs
- Oral (eating)
- Absorbed from gut slowly
- Onset is 1h
- Peak 2-3hrs
- Larger oral dose needed to have same effect as inhaled
Psychological effects
- Subjective effects (buzz, high)
- Sometimes mood swings to anxiety and/or panic, especially at higher doses
- Effects modulated surroundings
Psychodynamics
- Endogenous cannabinoid system (endocannabinoid; eCB)
- Endogenou ligands; anandamide (AEA) and 2- arachidonoylglycerol (2-AG)
- Two main receptors: CB1 (brain) and CB2 (immune system)
- Anandamide and THC bind to CB1
- 1-AG and CBD bind to both CB1 and CB2
THC: how it works in the brain
- CB1 receptors are located presynaptically on axon terminals
- THC mimic the shape of AEA and works by this mechanism
- Cumulative effect of pathways is euphoric feeling associate with cannabis use
Lecture 14 - Schizophrenia
Schizophrenia
- Psychotic disorder
- Psychosis
- Common disease (1/100), severe consequences
History
- Emil Kraepelin - Dementia praecox
- ‘Madness’ ‘lunacy’
- Dementia praecox
- Edgen Bleuler - schizophrenia - split mind
, Myths
- Violent and dangerous
- Multiple personalities
- See things that aren’t there
Characteristics / symptoms
- Positive: go beyond normal occurring experiences (hallucinations, delusions, paranoia)
- Negative: deficit of absence of normal behaviour (apathy, limited though/speech,
emotional and social withdrawal)
- Apathy: inability to ‘get started’, perform basic day-to-day tasks
- Autism: tendency to keep oneself and lose interest in other ppl or surroundings
- Ambivalence: emotional and social withdrawal
- Anhedonia: indifference to activities that are typically considered to be
pleasurable
- Affective flattening: absence of visible emotions, facial expressions and
emotional inflections in speech
- Cognitive: erratic changes in speech, motor behaviour and emotions (disorganized
speech, inappropriate emotions; reactions)
- Pathognomic: symptom unique to a specific disorder
DSM-5 criteria
- At least one: delusions, hallucinations, disorganized speech
- Diminished level of function
- Long-lasting symptoms
- Not due to drugs or a medical condition
Development
- Usually diagnosed in late adolescence / early adulthood
- Prodromal stage - 1-2 year period where subdues symptoms begin to appear (85% of
ppl)
Development and prognosis
- Complete remission is rare
- Pattern of relapse and recovery
- Prognosis is poorer than most other disorders
- recovery/remission more likely of:
- Good social adjustment prior to onset
- Low proportions of neg symptoms
- Good social supports system for patients
- Symptoms tend to decrease with age
Etiology - genetics
- Clear genetic link (not 100%)
Etiology - prenatal factors
- Virus exposure
- Stress
- Pregnancy delivery complications
Etiology - stress
- Stressful life event, stress and genetics interaction
