1. Localisation of memory
Chapter 28

2. Memory Brain’s capacity to retain & retrieve info
Versatile – sights, sounds, smells etc
Large capacity – experiences stored for a lifetime
Declarative memory (‘remembering that’):
Recall of personal or general facts
Associated with areas of the temporal lobe
Limbic system
– surrounds the hypothalamus
- Possesses the hippocampus
Procedural memory (‘remembering how to..’):
Ability to recall how to perform mental & motor skills
e.g reading, playing chess, swimming, cycling etc
Cerebellum very active

3. Localisation of memory
Amnesia – partial or complete loss of memory
Results from injury, surgery, disease, stroke, electrical shocks
Case history – removal of limbic system
Limbic system – formation & transfer of new declarative memories
Temporal lobes – storage of declarative memories
Cerebellum & cerebrum – storage of procedural memories
Personal & general memories stored in different areas
Memories of different categories stored in different areas
However, many areas interconnected (constant exchange of info)

4. Memory at neuronal level
Procedural skills not easily forgotten
Many declarative memories also permanently stored
Probably due to long-term change in the brain
Each memory held in a ‘memory circuit’ (group of neurones)
Retrieved by nerve impulses passing through & reactivating the circuit
Interchange allows one memory to trigger other memories

5. Molecular basis of memory
Memory likely based on chemical changes in neurones
Certain neurotransmitters released
– impulses flow through ‘memory circuits’
Increased impulses, memory is longer lasting
Alzheimer’s:
- abnormal tangled neurones
- brain cell death
- irreversible memory loss
- Cells in limbic system producing acetylcholine are lost
Monkeys – visually impaired if acetylcholine blocked

6. Molecular basis of memory (ctd.)
New memories dependent on hippocampus region
In this region, glutamic acid is the neurotransmitter released
This binds to NMDA receptor
- alters electrical state in postsynaptic membrane
Long term – neurones change biochemically
Proteins are synthesised – alter size and shape of postsynaptic neurone
More dendrites
More synapses
Increased sensitivity = stronger memory