7. Reward and addiction

Question 1

define reward

Answer 1

the motivational property of a stimulus that induces appetitive behaviour

Question 2

define appetitive behaviour

Answer 2

behaviour related to the desire to approach or to consume

Question 3

olds & milner 1954

Answer 3

self-stimulation in rats
septal region

• cocaine, food etc
• mirrored behaviour in humans

Question 4

name 4 different dopamine pathways

Answer 4

1. mesolimbic
2. mesocortical
3. nigrostriatal
4. tuberoINfundibular

Question 5

Dopamine goes primarily from _________ to _________________

Answer 5

VTA

to Nucleus Accumbens

Question 6

Name three brain structures also heavily involved in reward and addiction processes

Answer 6

Amygdala - emotional processing
Prefrontal Cortex - planning
Hippocampus - memory and learning

Question 7

define addiction

Answer 7

a chronic, complex mental illness

uncontrolled, compulsive drug seeking and use, despite negative health and social consequences

Question 8

name 2 defining characteristics of ADDICTION

Answer 8

• tolerance

- withdrawal

Question 9

name the three stages of addiction

Answer 9

1. Binge and Intoxication (feeling euphoric –> feeling good –> escaping dysphoria)
2. Withdrawal (reduced energy –> reduced excitement –> depression)
3. Preoccupation, anticipation (looking forward, planning how to get drug)

Question 10

methods of neuroadaptation

Answer 10

neurocircuits, synaptic systems, molecules, epigenetics

Question 11

neuroanatomical changes due to addiction

Answer 11

• upregulation of D1 receptors in dorsal striatum
• –> sensitization
• downregulation of D2 receptors
• –> loss of control

Question 12

at the synapse:

strong stimulation –> induction –>

Answer 12

increased release (presynaptic)
increased synapses
increased response

Question 13

ALCOHOL

- mechanism of action

Answer 13

• Positive allosteric modulator for GABAa
• -> Increase of GABA activity on DA
• Antagonist of NMDA glutamate receptors
• Opioid and endocannabinoid agonist

Question 14

NICCOTINE

- mechanism of action

Answer 14

AGONIST: alpha4/beta2 ACETYLCHOLINE receptors on the DA neuron

AGONIST: on Alpha 7 receptors on glutamate neurons from the prefrontal cortex

Question 15

which reuptake transporters does cocaine block?

Answer 15

monoamines

• noradrenaline
• serotonin
• dopamine
• adrenaline
• -> Monoamines accumulate in the synaptic cleft
• -> enhanced, prolonged sympathetic effect