Cannabis Use And Scizophrenia Flashcards
What did Moore et al (2007) find?
That cannabis can ‘increase risk of schizophrenia by 40%’
What evidence historically links cannabis to schizophrenia?
> Rastafarians are prone to psychotic illnesses
Schizophrenics are twice as likely to be regular cannabis users
Swedish study linking cannabis and mental health problems
How does cannabis effect dopamine?
> Increases mesolimbic dopeminergic firiong rates (via CB1)
Inhibits reuptake
Increases tyrosine hydroxylase
Increases synthesis and release
What did Bortolato et al (2014) find?
Evidence for increased dopamine turnover in the brain wrt cannabis use
What did Bloomfield et al (2014) find?
Chronic cannabis use reduces dopamine synthesis size, replicating alterations found in schizophrenia
Is cannabis always associated with increased dopamine function?
No, ~40% of studies disagree
What did Capsi et al (2005) find?
Chronic cannabis use can increase likelihood of schizophrenia IF user has COMT gene
The COMT gene increases the likelihood that an individual develops schizophrenia. What does COMT stand for?
Catechol-O-methyltransferase
Who found evidence that the COMT gene can increase the likelihood of schizophrenia in cannabis users?
Capsi et al (2005)
What COMT genotype is most susceptible to schizophrenia?
Val/Val (over 10x more likely)
What did Radhakrishan et al (2014) find?
That individuals with the Val/Val homozygote of COMT are likely to develop schizophrenia
Who identified the importance of the Val/Val homozygote of the COMT allele wrt schizophrenia?
Radhakrishan et al (2014)
What did Forti et al find?
That the C/C variant of the AKT1 genotype increases psychosis likelihood 7x in conjunction with heavy cannabis use
What are the possible confounding factors of all research exploring cannabis use and schizophrenia?
> Polydrug > Population homogeneity > Self-reporting biases > Definitions > Possibility of self-medication
