Recreational drugs and neurotransmitters

Question 1

Recreational drugs

Answer 1

• Recreational drugs are drugs taken for enjoyment rather than medical reasons
• They affect the levels of an existing neurotransmitters in the central nervous system, increasing or decreasing its levels at the synapse

Question 2

Stimulant

Answer 2

• Drugs that elevate mood, increase feeling of wellbeing and increase energy and alertness

Question 3

Opioids

Answer 3

• Painkillers, opioids produce a quick, intense feeling of pleasure followed by a sense of well-being and calm

Question 4

Sedatives

Answer 4

• Slow down normal brain function and produces a drowsy or calming effect

Question 5

Hallucinogens

Answer 5

• Drugs which cause altered perception and feeling, such as seeing colour or hearing things that are not there

Question 6

Cocaine

Answer 6

• Is a stimulant drug and mainly acts on the neurons of the brain’s main rewards system, the mesocorticolimbic pathway
• This pathway connects the subcortical areas of the brain to the frontal areas of the brain, including the nucleus acumens which is highly associated with rewards and dopamine
• Dopamine is the reward neurotransmitter that causes pleasant feeling and encourages us to repeat the behaviours to make us feel good

Question 7

Action of cocaine on dopamine receptors

Answer 7

• Normally, the action potential travels down the neuron and causes neurotransmitters to be fired (Dopamine)
• The presynaptic neuron will absorb the excess dopamine back into the cell
• Cocaine mimics the structure of dopamine which then blocks the receptors at the terminal buttons leads to that dopamine molecules staying in the synapse, leading to a large build-up the binds to the postsynaptic neuron.
• An excess of dopamine creates the high that people fell when taking cocaine.

Question 8

Effect of cocaine

Answer 8

• Overtime, the dopamine receptors become downregulated, so fewer receptors are active as they have been damaged
• So, the overall quantity of dopamine in the body is decreased, so withdrawal happens and craving the drug to feel the same effect again

Question 9

Heroin

Answer 9

• Is a opioid drug so it depresses it slows down the CNS activity, including the neurons that process pain, it is mainly injected by a needle and acts on the neurons with opioid receptors in the cerebral cortex, limbic system and hypothalamus
• These opioid receptors trigger the opioid receptors in the brain
• Opioids are the body’s natural painkiller and can lead to feeling of relief

Question 10

Action of heroin on opioid receptors

Answer 10

• Opioid receptors in the brain tell the cerebral cortex, limbic system and hypothalamus to release more endorphins
• As the heroin occupies the opioid receptors for much longer than normal neurotransmitters, the opioid system releases excess levels of endorphins, causing the person to feel sense of pleasure.
• Over time the opioid receptors become downregulated, so fewer receptors are active
• Overall, the quantity of opioid un the whole brain declines. Which explains withdrawal and craving the drug and tolerance
• The negative symptoms of heroin are significant as the body makes less endorphins to compensate for the overload of dopamine and these pains make the drug user to crave the drug even more