Different structures of the brain play distinct roles in forming and storing memories. This lesson covers the hippocampus, cerebellum and amygdala, and the conditions that cause memory loss.
1. Brain structures and memory
- Hippocampus — central to the formation and storage of memory, particularly the consolidation of new explicit (declarative) memories.
- Cerebellum — involved in the formation and storage of implicit (procedural) memories, such as motor skills.
- Amygdala — involved in the formation of memories, especially attaching emotional significance. It plays a key role in the emotional component of memories, the formation of fear responses, and attaching emotional significance to memories.
2. Causes of memory loss
- Trauma — Chronic Traumatic Encephalopathy (CTE): associated with repeated head trauma.
- Degeneration — Alzheimer's disease: a degenerative disease. Early-stage patients have difficulty with recall and encoding in short-term memory; later stages affect most parts of memory, with confusion about time and place, declining concentration, and changes to mood and personality.
- Drug-induced — Wernicke-Korsakoff Syndrome (WKS): associated with thiamine deficiency. Diagnostic criteria include anterograde amnesia; patients may also show retrograde amnesia, confusion, eye-movement disturbance, and lack of coordinated movement (ataxia).
Work through these together.
Matching structures to roles
For each scenario, identify the brain structure most involved:
Learning to ride a bike:
Forming a vivid, fearful memory of a car accident:
Consolidating the facts learnt in today's lesson:
Contrasting the conditions
As a class, complete a comparison of the three causes of memory loss by category:
CTE → cause:
Alzheimer's disease → cause:
Wernicke-Korsakoff Syndrome → cause:
Answer independently, using examination-style directive verbs.
Q1. State three roles of the amygdala. (3 marks)
Q2. Explain the amygdala's potential role in the process of classical conditioning. (5 marks)
Q3. Outline two possible changes in a person's ability to form memories resulting from damage to the hippocampus. (2 marks)
Q4. Chronic Traumatic Encephalopathy (CTE) is a condition associated with memory loss. Name and outline two other conditions associated with memory loss, identifying two main features of each. (8 marks)