BLOA - explain effects of neurotransmission

Question 1

functions of neurons

Answer 1

• send electrochemical messages to the brain

- so people can respond to stimuli either from the environment or from changes in the body

Question 2

neurotransmitters

Answer 2

• natural chemical messengers that transmit info between two neighbouring neurons via synapses
• they have specific and highly localized, short-lived effects
• different chemicals can affect behaviour by imitating, increasing the secretion of, or blocking natural neurotransmitters

Question 3

effects of neurotransmitters

Answer 3

• each neurotransmitter has a different effect on human behaviour
• serotonin is purported to improve mood and serotonin-facilitating drugs (e.g. Prozac) are used to treat depression
• acetylcholine stimulates muscle movement and is believed to play a role in learning memory formation

Serotonin studies:

• Kasamatsu and Hirai (1999)
• Marazziti (1999)

Acetylcholine study: Martinez and Kesner (1991)

Question 4

process of neurotransmission

Answer 4

method by which messages are sent

• when nerve impulse reaches end of the neuron, the neuron fires neurotransmitters that are released into the synaptic gap
• they bind to receptors on the post-synaptic neuron
• un-absorbed neurotransmitters are re-uptaken, diffused, or destroyed
• if a neurotransmitter is blocked or replaced due to the interference of another chemical, then the messages alter
• this affects the physiological system, cognition, mood, or behaviour

Question 5

transmission process

Answer 5

1. neurotransmitters are stored in vesicles inside the axon
2. vesicles exit the nerve cell via exocytosis, releasing the neurotransmitters into the synaptic gap
3. neurotransmitters bind with a receptor site on the next neuron if the receptor site is the right type of receptor + is vacant (lock-and-key, like enzymes)
4. if enough of the neurotransmitter binds to the receiving neuron’s receptor sites, the neuron will transmit information across its cell body electrically to release neurotransmitters
5. unused neurotransmitters are eventually reabsorbed back into the neuron it came (reuptake) to be reused next time

Question 6

what to write when asked: “explain the effects of

neurotransmission on human behaviour”

Answer 6

• define neurons and outline their functions
• define neurotransmission and describe its process
• define neurotransmitters and describe their effects
• define serotonin and acetylcholine
• main idea: different neurotransmitters affect different behaviours, and in different ways
• explain WHY those effects occur
• serotonin: Marazzitti (1999) on OCD and love, Kasamatsu and Hirai (1999) on Japanese monks’ sensory deprivation causing hallucinations
• acetylcholine: Martinez and Kesner (1991) on rats’ memory