NEUR Addiction and Cannabis

Why you should not call someone an addict?

Calling someone an “addict” dehumanizes that person and can link a substance use disorder to their individual identity. A person is not defined by their illness or health condition.

What is a person first language?

acknowledges someone as a person before describing their personal attributes or health conditions. It does not identify people by secondary or incidental qualities or conditions instead of “addict” use “person with a substance use disorder”.

What language should you avoid?

avoid using language like asking someone if they are clean or dirty. These terms can decrease self-esteem and effectiveness of treatment for someone suffering from a substance used disorder.

What is an addiction?

a syndrome at the centre of which is a loss of control over reward seeking behaviour

What is reward?

refers to stimuli that are in someway, desirable or positive and can affect behaviour. People find certain activities to be rewarding. This is with good reason as rewarding activities are usually critical to survival.

What is rewarding stimuli?

it can be different depending on an individuals personal experience, we learn to value more than just what we were born liking. The ability to learn new rewards is also valuable because it teaches us to repeat successful behaviours

Discovery of the reward

Olds and Milner discovered intracranial self simulation by accident

What is intercranial self stimulation?

in the first experiment, a rat was fitted with an electrode located in a certain part of its brain. This electrode was connected to a stimulator that was controlled by a lever in the rat's cage. The rat could self stimulate that part of his brain when pressing the lever. Rats would press the lover thousands of times an hour, ignoring everything else that the experimenters could offer they ignore food, water, and sexual females. The rats would eventually collapse from exhaustion. This behaviour closely resembled the behaviour of human drug addiction. They concluded that the areas targeted by the electrodes must be involved in drug addiction.

What is the mesocorticolimbic dopamine system made of?

ventral tegmental area (VTA) this contains neurons that produce dopamine. Axons from these neurons project to the hippocampus, nucleus accumbens, prefrontal cortex

What is the mesocorticolimbic dopamine system?

when rewarding stimulus is detected, neurons in the VTA are activated. They released dopamine into the prefrontal cortex NAc and hippocampus

what is the mesocorticolimbic dopamine system on drugs

addictive drugs lead to supraphysiological dopamine. A dopamine release that is much larger than what would normally be seen with the naturally occurring rewards.

How is the mesocorticolimbic dopamine system affected with drugs?

every drug affects the system in someway it increases the dopamine release in the nucleus accumbens.

What is the purpose of dopamine release in the nucleus accumbens mesocorticolimbic dopamine system?

a teaching signal. This is related to the expectation and experience of a rewarding stimulus, unexpected rewards lead to especially large dopamine release. Together with the prefrontal cortex and hippocampus this system allows for the experience of reward as well as the learning needed to go after it again.

How do we diagnose addiction?

patient's show two or more of 11 behavioural criteria within the past year. 1 is using in spite of adverse consequences, 2 is the pre-occupation with obtaining the drug, and 3 is the great deal of time spent trying to get the drug

What is drug tolerance?

increased amount of drug needed to achieve intoxication, or a diminished drug effect with continued drug use of the same amount of drug. Can become tolerant to some aspects of a drug, but not to others can also have very high blood levels of a drug and not appear intoxicated.

What is drug withdrawal?

acute and protracted drug use leads to drug withdrawal. Behavioural and physiological symptoms that occur upon stopping the drug severity may change with characteristics of the user, could be hangover, muscle aches, and cramps.

What are the four stages of withdrawal effects?

1. The brain normally exists in a state of drug free homeostasis 2. Taking drugs leads to an imbalance 3. Compensatory adaptations attempt to restore homeostasis 4. Withdrawal quitting drugs, leads to an imbalance in the opposite direction.

How common are substance use disorders?

Varies across countries and by substance, 4% of the population will receive a diagnosis of substance use disorder. 87% of Canadians use substances.

What is the adverse child experience scale?

scale that assesses negative childhood experiences such as risky health behaviors, chronic health conditions, increased morbidity, and mortality.

What is cannabis?

most used illegal drug in the world, most controversial, has medicinal properties, comes from the cannabis sativa plant. Has over 80 cannabinoids most common is the 9- tetrahydrocannabinol (THC), is the main psychoactive ingredient responsible for the high associated with the use.

What is the cannabis administration inhalation (smoking)?

50% enters lungs almost all of that enters the body, reaches the brain in 30 seconds, peaks in 30 to 60 minutes, last 3 to 4 hours, subjective state for 12 hours. Vaping. peak occurs in 10 minutes. Distributed everywhere likes to stay in fatty tissue.

What is the cannabis administration oral edibles?

absorbed from gut slowly, absorption improved by adding oil. Onset is one hour peak is 2 to 3 hours. You need a larger oral dose to have the same effect as inhale.

What is the cannabis psychological effects?

cognitive, behavioural and emotional, perceptual

What is the cannabis psychological effects cognitive?

decreased attention, concentration, learning

What is the cannabis psychological effects behaviour and emotional?

decreased movement, increased talkativeness

What is the cannabis psychological effects perceptual?

decreased visual, pain, and time perception

What is cannabinoid PHARMACODYNAMICS?

their exists and endogenous cannabinoid system. System is activated in times of stress. It helps regularly in return to baseline.

What is cannabinoid PHARMACODYNAMICS the 2 endogenous ligands?

anandamide (AEA) and 2-arachidonoylglycerol (2-AG), two main receptors CB1 (brain) CB2 (immune system), Anandamide and THC bind to CB1, 2-AG and CBD bind to both CB1 and CB2

How to Endocannabinoids work

CB1 receptors are located pre-synaptically on axon terminals. AEA and.2 AG are retrograde messengers. They carry information in the opposite direction from normal their synthesized and release in response to depolarization of the postsynaptic cell. It is the brain's own brake system.

How does THC work?

Mimics the shape of AEA and works by exploring this mechanism. THC binds to the CB1 receptor pre-synaptically, it inhibits further release of neurotransmitters. The cumulative effect of pathways is euphoric feeling associated with cannabis use

Cannabis and psychosis

studies suggest frequent use of high THC cannabis is associated with an increased risk of developing psychotic symptoms, especially in young males using daily or near daily before the age of 16 and have a variation in the COMT gene

Recent studies of psychosis and cannabis

people who had a history of frequent cannabis use and experienced their first psychotic episode had a unique epigenetic change on genes associate with immune functioning and metabolic functioning

Cannabis and mental health

high THC use is associated with an increased risk of developing depression. However, people who have depressive symptoms also are more likely to use.

Cannabis and mental health suicide rates

heavy or frequent use in younger populations may be linked to an increased risk of suicidal thoughts, attempts and behaviours

Who is using cannabis?

16 to 24-year-olds are 2x more likely to use cannabis, students use more than working and unemployed people, average age of initiation is 18.7 years, of those who reported use 18% use daily.

Problematic cannabis use is predicted by?

being male, using alone and with others, using dried flower product, primary motivation is boredom or to cope with stress