Schizophrenia and marijuana

who coined the term schizophrenia?

P.E. Blueler

what is the DSM 5 criteria for schizophrenia?

1. 2+ of the following, each present for a significant portion of time during a 1-month period (or less if successfully treated). One must be (a), (b), or (c):

   1. Delusions

   2. Hallucinations

   3. Disorganized speech (e.g., frequent derailment or incoherence)

   4. Grossly disorganized or catatonic behaviour

   5. Negative symptoms (e.g., diminished emotional expression or avolition)

2. f or a significant portion of the time since the onset of the disturbance, level of functioning in one or more major areas, such as work, interpersonal relations, or self-care is markedly below the level achieved prior to the onset (or when the onset is in childhood or adolescence, there is failure to achieve expected level of interpersonal, academic, or occupational functioning) 

3. Continuous signs of the disturbance persist for at least 6 months. This 6-month period must include at least 1 month of symptoms (or less if successfully treated) that mean criterion A (e.g., active-phase symptoms) and may include periods of prodromal or residual symptoms. During these prodromal or residual periods, the signs of the disturbance may be manifested by only negative symptoms or by two or more symptoms listed in Criterion A present in an attenuated form (e.g., odd beliefs, unusual perceptual changes)

4. The disturbance is not attributable to the physiological effects of a substance or another medical condition

describe the schizophrenia spectrum

less severe to more severe

delusion disorder → brief psychotic disorder → schizophreniform disorder → schizophrenia → schizoaffective disorder

what are the most common positive symptoms of schizophrenia?

hallucinations

delusion

what are some of the main cognitive issues that those with schizophrenia hve

attention

memory

what parts of Schizophrenia is more commonly seen in males?

negative symptoms are more likely seen

what parts of schizophrenia is more commonly seen in females?

depressive episodes, paranoid delusions, and hallucinations

describe the general genetic risk factors regarding schizophrenia

if a direct family member has schizophrenia, then it is highly heritable and the risks go down as the genetic distance increases from the affected individual.

describe the enviornmental and developmental risk factors regarding schizophrenia

• Maternal infection (e.g., influenza, herpes simplex 2)

• Maternal age <20 and 30-34; paternal age <20 and >35

• Maternal active mood disorder

• Childhood adversity

• Migration status (males > females): first and second generation

• Urban environment (males only)

• Stressful life events

• Winter birth (males only)

• Substance misuse (females > males)

• Cannabis use

what is the most common treatment for positive symptoms in schizophrenia?

antipsychotic drugs

explain the dopamine theory of schizophrenia

schizophrenia is caused by too much activity at dopamine receptors

1. in the brain of those with Parkinson’s disease have low dopamine levels; antipsychotic drugs block dopamine and causes similar side effects to parkinsons. Dopamine reduction affects movement and the brain in similar ways in both conditions

2. drugs that increase dopamine levels like amphetamine or cocaine produce symptoms of schiozphrenia. Too much dopamine can produce psychosis-like effects

3. efficacy of antipsychotic drug correlates with the degree to which it blocks activity at dopamine receptors. Dopamine activity is related to schizophrenia treatment

what are some problems with the dopamine theory of schizophrenia?

1. atypical antipsychotics changed many things in the brain, including dopamine but worked just as well meaning that dopamine can’t be the only thing involved

2. dopamine blocking occurs immediately after antipsychotic drug consumption but symptom relief is not immediate. Suggesting that other brain changes are needed for improvement of symptoms

3. many people don’t get better on the first antipsychotic drug they try and some don’t respond well to any dopamine-blocking medication. Meaning that dopamine is not the whole story

what is the glutamatergic hypofunction theory?

when glutamate can’t activate its receptors properly, the brain’s balance between calm and active signals is thrown off — which may lead to symptoms of schizophrenia.

what is the immune dysfunction theory of schizophrenia?

schizophrenia is the result of problems with the immune system

1. certain infections increase risk of psychosis

2. higher risk of schizophrenia in people with autoimmune diseases

3. many genes that are associated with schizophrenia have immune system functions

4. psychosis is a feature of an autoimmune disorder where antibodies attack NMDA-type glutamate receptors

describe who are at high risk of developing schizophrenia (in terms of brain scanning)

those with increased dopamine activity in the brain in areas like the striatum

what is marijuana?

a psychoactive drug derived from the Cannabis plant

what are the three species of cannabis?

Cannabis sativa, Cannabis indica, and Cannabis ruderalis.

what are cannabinoids

the active chemicals in cannabis plant

what are the main cannabinoids in marijuana?

The primary cannabinoids in marijuana are tetrahydrocannabinol (THC) and cannabidiol (CBD)

what is hashish

Hashish is a concentrated form of cannabis made from the resin of the plant, often containing higher levels of THC.

describe the pharmacology of marijuana

The pharmacology of marijuana involves the interaction of cannabinoids with the body's endocannabinoid system, leading to effects on mood, pain perception, and appetite, primarily through receptors CB1 and CB2.

what is the first endogenous cannabinoid discovered?

anandamide

what is anandamide?

Anandamide is an endogenous cannabinoid neurotransmitter that binds to cannabinoid receptors in the brain, playing a role in pain, mood, and memory.

describe the acute psychological effects of marijuana

low dose

• subtle effect and unobservable

• increased sense of well-being

• alterations in space and time perception

• heightened sensations

high dose

• impairments in psychological functioning

  • episodic and working memory impairment

  • multi-step goal-directed task impairment

  • speech production impairment

transient psychosis is possible

describe the chronic cognitive effects of marijuana

working memory impairment

What happens to cognitive impairments from marijuana use after stopping for several weeks?

rarely present after 4–6 weeks of abstinence from marijuana.

describe the chronic physiological effects of marijuana in vitro and primates

• THC and CBD suppress tumour cell proliferation in vitro

• cannabinoids inhibit synapse formation during development in vitro

• vivo primate: no longer-term effect of chronic cannabinoid consumption on brain neurochemistry and structure

describe chronic physiological effects of marijuana in humans

• chronic cannabis use associated with down regulation of CB1 receptors

• conflicting evidence in brain gray matter differences

• DTI: differences in interhemispheric tracts (smaller corpus callosum)

describe the chronic psychological effects of marijuana

daily high-potency cannabis use associated with

• increased risk of psychosis, depending on dose

• earlier onset of psychosis compared to low potency cannabis

• CBD leads to behavioural responses in schizophrenics that is similar to atypical antipsychotics

what is the cannabis-use disorder (CUD)?

Cannabis-use disorder (CUD) is a condition characterized by the compulsive use of cannabis despite adverse consequences, including impaired functioning and withdrawal symptoms. It may lead to increased tolerance and cravings for the substance.

describe the relationship between high-potency cannabis and CUD

far more likely to be at risk for CUD

Describe the history of cannabis and marijuana.

The history of cannabis and marijuana involves its use as a medicinal and recreational drug dating back thousands of years, with significant cultural and legal changes over time, including prohibition and recent legalization efforts.