AO3: Types of LTM

• Evidence from case studies to support separate LTM

  HM highlights the distinction between procedural and declarative memories. HM was able to learn new procedural information under experimental conditions (drawing by looking at his reflection), however, he had no idea that he had learnt this. This highlights the case for multiple LTM because he had the ability to form new procedural memory but not any new episodic or semantic memories. Implying that LTM isn't a single unitary store and that he had actually only damaged 2 of 3 LTM stores.
• Issues with case studies

  It is difficult to conclude from case studies like HM the exact parts of the brain which have been affected. This is because damage to particular areas doesn't mean it is responsible for a particular behaviour. Therefore, it is difficult to conclude casual relationships between brain area and type of LTM.
• Evidence from brain scans to support separate stores

  Episodic and semantic memories were recalled in an area of the brain called the temporal lobe, in the prefrontal cortex. Procedural memory was dealt with in the cerebellum. This suggests that different areas of the brain are responsible for recalling different types of long term memories. Meaning that LTM must be separate stores located in different areas of the brain.
• Research to support using Alzheimer's patients


  Hodges and Patterson found that some patients with Alzheimer's retain the ability to form semantic memories but have a profound episodic disorder. Irish on the other hand found the reverse, poor semantic memory but the ability to retain episodic memories. Either way, if LTM was a unitary store, all patients would not be able to form new long term memories. However, some can retain this ability and can form new long term memories which means LTM must be separate stores.