recreational drugs

• Synaptic transmission


  1. Electrical impulse travels along pre-synaptic neuron

  2. Impulse reaches synaptic vesicles to release neurotransmitter

  3. Neurotransmitter diffuses across synaptic gap and attaches to receptors
• Heroin


  • Changes into morphine
  • Binds to opioid receptors
• Nicotine


  Stimulates acetylcholine receptors
• Alcohol


  • Depressant effect
  • Increases GABA
  • Slows down Noradrenaline
• Recreational drugs


  Increase or decrease neurotransmitters in the synaptic gap
• Heroin


  • Increases dopamine, providing feelings of euphoria and pleasure
• The neurotransmitter explanation has played a vital role in developing our understanding of behaviours such as mental health and addiction, improving people's quality of life
• We should also consider the role of alternative explanations to achieve a holistic approach to explain behaviour in the most effective way
• Central Nervous System


  • Consists of the brain and spinal cord
  • It is the central processing and control point for all human behaviour
  • The brain processes all incoming information from the senses
  • The spinal cord connects the brain and the rest of the body, and allows messages to be passed between the body and the brain
• Neuron


  • Cells within the central nervous system which communicate chemical messages between each other in a huge network, through synaptic transmission
  • To change behaviour, such as mood
• Neurotransmitter


  • Chemicals which pass messages across the synaptic gap between neurons through synaptic transmission
  • Affect mood, attention and memory
• How messages travel along a neuron

  1. Neurons consist of a cell body which contains the nucleus

  2. Attached to the cell body are dendrites that receive messages from other neurons in order to trigger an action potential (electrical impulse) which travels down the axon

  3. Fatty deposits called myelin sheath provide insulation helping to speed up message transmission

  4. Breaks between the myelin sheath are called nodes of Ranvier

  5. At the end of the axon are axon terminals with terminal buttons containing vesicles that store neurotransmitters
• GABA


  Inhibits messages & produces a calming effect
• Glutamate


  Used for cognitive functioning
• Acetylcholine


  Used for memory, attention & learning
• Serotonin


  Regulates mood, sleep & appetite
• Dopamine


  Associated with pleasure & reward & addictive behaviours (drugs & behavioural)
• Adrenaline


  Prepares body for fight/flight response; aids attention
• Synaptic transmission


  1. An action potential (electrical impulse) travels along an axon

  2. This triggers the nerve-ending of a neuron to release neurotransmitters from vesicles

  3. They diffuse across the synaptic gap and bind with specific receptor sites on the postsynaptic neuron (eg dopamine binds to D2)

  4. This stimulates the second neuron to create an action potential, transmitting the message

  5. Any neurotransmitter molecules which haven't been absorbed by the postsynaptic neuron, get absorbed back into the presynaptic neuron (this is known as reuptake) or are destroyed
• Agonist


  A chemical which mimics a neurotransmitter which binds to a receptor, activates it to produce a reaction
• Antagonist


  A chemical which mimics a neurotransmitter which binds to a receptor and blocks it, producing no reaction
• Reuptake


  Unused neurotransmitter molecules are absorbed back into the presynaptic neuron and is then either destroyed by enzymes within the neuron or is reused
• SSRI (Selective Serotonin Reuptake Inhibitor)


  Works by blocking the reuptake of serotonin, leaving more in the synapse so that it can reach the post-synaptic neuron, resulting in the serotonin message being passed along, improving mood
• Drugs are biochemicals which affect the functioning of systems in the body
• Physiological treatments e.g. antibiotics
• Psychological treatments e.g. antidepressants
• Recreational drugs e.g. heroin affect transmission in the central nervous system but are taken for pleasure