Biological psych 10: Addiction (Lec 35)

Question 1

What’s the difference between dependence and addiction?

Answer 1

Physical symptoms: Dependency comes before addiction

Question 2

How does dopamine control behaviour? Name 3 important aspects

Answer 2

• It acts as a signal for salient events eg signal for something good about to happen
• Organises behaviour in order to obtain important ‘good’ things (eg food)
• assists decision of what will be most rewarding

Question 3

What is a cannula?

Answer 3

a thin tube inserted into a vein or body cavity to administer medication, drain off fluid, or insert a surgical instrument.

Question 4

What was the effect of cannula insertion stimulating the nucleus accumbens for research participants w un-treatable major depression in the 2007 study? What did this further establish about the role of the nucleus accumbens in the ventral striatum pathway?

Answer 4

Immediate behavioural responses: A sharp increase in exploratory behaviour. This further established the role of the nucleus accumbens for reward seeking and motivation

Question 5

What happened to the major depressive symptoms when the cannula stinulator was turned on in the nucleus accumbens in the ventral striatum reward pathway?

Answer 5

Depressive symptoms dropped while the stimulator was turned on, although the participants didn’t necessarily notice that, their motivation increased during activation

Question 6

How would you sum up the effects of dopamine, since its main role is not associated with pleasure of rewards?

Answer 6

It signals the significance and salience of rewards

Question 7

Name the 4 defining diagnostic criteria for substance addiction (plus 1 preluding…)

Answer 7

1. Repeated use
2. Diminished control (unable to reduce)
3. Compulsion and craving (motivating the behaviour)
4. Salience: Focus on use superseding other interests and hypervigilence to cues
5. Tolerance & withdrawal: Rewarding, +ve rft of use increases tolerance and discontinuation has physical and psychological consequences

Question 8

Give an example of -ve rft which would reinforce drinking alcohol

Answer 8

Diminishes anxiety

Question 9

What is the neuropharmocological explanation for drug tolerance?

Answer 9

eg dephosphorelation of receptors: Active membrane receptors are silenced after binding to neurotransmitter- they become rapidly inactive whilst they’re being endocytosed and repurposed, which causes tolerance as the receptors are no longer at the cell membrane to receive the neurotransmitter.

Question 10

What is the diff between tolerance and chronic tolerance?

Answer 10

Chronic tolerance: there is actual loss of receptors and new receptors are not being made

Question 11

Taking the same dose of heroine, but in a different environment, and experiencing an overdose is an example of

Answer 11

psychological tolerance

Question 12

Describe tolerance from a perspective including the body’s homeostasis maintenance system

Answer 12

As tolerance increases and drug effects are diminished, homeostasis response also increases due to drug-taking cues, this increase which compensates the effects of the drugs can start even before the substance effect takes place

Question 13

Why do ppl get so excited before drinking?

Answer 13

Hyperarousal: Their bodies are preparing for an increase in GABA (suppressant)

Question 14

What is the ‘b’ process (bodies reaction) to cocaine or MDMA?

Answer 14

Hypo-arousal, amotivational state

Question 15

What is the main characteristic of PD (Parkinson’s Disease)? How was this shown?

Answer 15

Loss of dopamine producing neurons, therefore loss of dop transporters.

This was shown using PET scans, (radioactive colouration, red-blue spectrum for density high-low)

Question 16

Speed causes _____ loss whereas MDMA causes _____ loss

Answer 16

dopamine-producing neurons, serotonin-producing neurons

Question 17

What is the insular cortex important for?

Answer 17

Particular bodily sensations such as nausea, and emotional responses such as disgust

Question 18

Which parts of the brain are activated in cannabis-dependent users when they viewed cannabis cues which were so fast they could not be detected? Name the part exclusive to cannabis cues as well as mutual to non-cannabis cues

Answer 18

Ventral striatum exclusively for cannabis cues, insula cortex and amygdala mutually for non-cannabis cues

Question 19

Which parts of the brain are activated in cannabis-dependent users when they viewed cannabis cues which were so fast they could not be detected? Name the part exclusive to cannabis cues as well as mutual to non-cannabis cues

Answer 19

Ventral striatum in the reward circuitry, exclusively for cannabis cues, insula cortex and amygdala mutually for non-cannabis cues

Question 20

Which part of the cortex is related to how long subjects have been using marijuana, when viewing momentary marijuana cues?

Answer 20

Motivational regulation regions in the PFC, organised at the level of the orbitofrontal cortex

Question 21

Which part of the brain becomes heavily active for cocaine users when they think/ talk about cocaine? Why is this?

Answer 21

Orbitofrontal cortex, because it organises the drive to take the drug

Question 22

What happens to the medial prefrontal cortex in addicts, and how does this effect people?

Answer 22

The medial prefrontal cortex shrinks, which effects regulation of emotions and motivations

Question 23

Describe Wolkow’s model of addiction

Answer 23

In the non-addicted brain, the mPFC controls the reward, drive and memory cycle, but in the addicted brain, there is hyperactivation of reward, drive and memory, disregulating connectivity with the mPFC

Question 24

What are the 4 steps of neuroadaptation which lead towards addiction?

Answer 24

1. Sensitisation of dopamine pathway
2. Adjustment to drugged state and emotional turmoil without drug
3. Repeated actions become habits (often)
4. Poor decision making (disordered PFC)

Question 25

What is the treatment rate for air pilots to enter rehab programs for alcoholism after judge ruling that they’d lose their job?

Answer 25

97%