Psychology: Biopsychology

SUBJECT CHECKLIST

1. The Divisions of the Nervous System

2. The Structure & Function of Neurons

3. Synaptic Transmission

4. Excitation & Inhibition

5. Endocrine System

6. Fight or Flight Response

7. Localisation of Function & Hemispheric Lateralisation

8. Language Centres

9. Split Brain Research

10. Plasticity & Functional Recovery

11. Ways of Studying The Brain

12. Circadian Rhythms56

13. Infradian Rhythms

14. Ultradian Rhythms

1.The Divisions of the Nervous System

• Nervous System: primary internal communication system: collects, processes & responds to info from the environment; coordinates the working of different organs/cells in the body

• CNS:

  • Brain:  involved in conscious / voluntary processes

  • Spinal Cord: relays information between the brain and the rest of the body: regulates and monitors involuntary bodily processes such as digestion & breathing + coordinating voluntary movements: nerve cells = simple reflexes without the direct involvement of the brain

• PNS:

  • Somatic NS: voluntary muscle movement & recieves info from sensory receptors, involved in reflex actions

  • Autonomic NS: involuntary/automatic functions such as breathing & heart rate

    • Sympathetic branch: fight or flight response, helps to prepare the body for the rapid action needed when facing a threat (increased HR)

    • Parasympathetic branch: restores the body back to its resting state after the emergency has passed… rest and digest system

2. The Structure & Function of Neurons

• Nucleus: control centre of a cell → chromosomal DNA

• Dendrite: receives nerve impulse → carries towards the cell body

• Axon: carries the impulse away away from the cell body

• Myelin Sheath: protects the axon from external influences that may affect transmission

• Nodes of Ranvier: speed up transmission by causing the impulse to ‘jump’

• Terminal Buttons: end of an axon, communicate with next neuron in the chain across the synapse

• Sensory Neuron:

  • PNS, in sensory organs, receive info from the environment and carry message from the PNS to the brain & spinal cord

  • Long dendrites and short axons

• Relay Neuron:

  • CNS, transfers messages from sensory neurons to other interconnecting ones/motor neurons

  • Short dendrites and long/short axons

• Motor Neuron:

  • PNS, Carry messages from CNS → effectors (muscles/glands)

  • Short dendrites, long axons

3. Synaptic Transmission

1. Action potential (explosion of electrical activity) occurs when a neuron sends info down an axon → away from the cell body

2. Electrical impulse & end of the neuron → vesicles bind with the presynaptic membrane

3. Bind→ release neurotransmitters across the synaptic cleft & attach to receptors on the postsynaptic membrane

4. Chemical → electrical impulse that travels in one direction

Neurotransmitters:

• ‘Synaptic vesicles containing the neurotransmitters are only present on the presynaptic membrane → diffusion in one direction, high to low concentration

• A neurotransmitter = chemical messengers that carry signals from neurons to other cells, they are released from axon terminals after action potential occurs. They have a specific molecular structure, lock and key with the receptor!

• Examples:

  • ACH → motor neurons & muscles, when released the muscle contracts

  • Dopamine → regulation of pleasure & motivation. Reward system: high levels in schizophrenic patients, low in Parkinson's

4. Excitation & Inhibition

• Excitatory neurotransmitters = noradrenaline → on switches, increase likelihood of neuron firing. Binds…