TYPES OF LTM.

LTM.

Long term memory is divided into two main types called explicit memory meaning - knowing that - and implicit memory meaning - knowing how -

Within explicit memory there are two types of memories called episodic and semantic memories.

Within implicit memory there is procedural memroies.

Episodic memory.

It is the memory of autobiographical events.

Event, context and emotions associated.

It is explicitly stated.

It is the collection of past personal experiences that occurred at a particular time and place.

For example, if you remember the party on your 6th birthday, this is an episodic memory.

They allow you to figuratively travel back in time to remember the event that took place at that particular time and place. They are ‘time stamped’ (you know when the memory was made) and ‘declarative’ (you have to consciously ‘search’ for the memory).

Semantic memory.

Sometimes called generic memory, this refers to the memory of meanings, understandings, and other concept-based knowledge.

Semantic memory underlies the conscious recollection of factual information and general knowledge about the world

For example, knowing what the capital city of Italy is, or how many pounds there are in a stone.

The memories are not usually time-stamped, and they are declarative.

Procedural memory.

The memory for the performance of particular types of action.

Procedural memory guides the processes we perform and most frequently resides below the level of conscious awareness.

When needed, procedural memories are automatically retrieved and utilised for the execution of the integrated procedures involved in both cognitive and motor skills, from tying shoes to flying an airplane to reading.

These memories are not usually time-stamped, and are non-declarative (implicit)- they don’t need to be consciously recalled.

Evaluation.

Case Study.

The case of Clive Wearing supports that there are different types of LTM.

  • Following a brain infection, Wearing’s procedural memory seemed intact (e.g. being able to dress himself and even play the piano).
  • However, his episodic memory was severely damaged. When his wife left the room and returned, even after only a few minutes, he would greet her as if they had not seen each other for years.
  • He kept a diary in which he constantly wrote that he was just regaining consciousness every few minutes.

However...

Cases such as Clive Wearing are hard to use as evidence as it is not conclusive as it is only one individual or extrudate firm conclusions from one person's experiences.

Brain Scanning.

: Scientific evidence captured from brain scans supports the view that there are different types of long-term memory.

  • For example, when asking participants to recall different types of information different areas of the brain are shown to be active.
  • Episodic memories are associated with the hippocampus.
  • While, semantic memories with the temporal lobe and procedural memories with the cerebellum.

This is a strength because it provides objective evidence that different LTMS activate different areas of the brain which supports the idea that there are different types of long-term memories.

Conflicting evidence.

  • This is a weakness because the findings cannot be generalised beyond the research.
  • It would be inappropriate to assume that everyone’s LTM is formed in the same way based on evidence of two case studies.
  • This means that while informative, the research findings can’t be generalised beyond the research, but does provide a good solid basis on which further research can be conducted.

There are conflicting research findings linking types of LTM to areas of the brain.

Buckner and Peterson 1969.

  • Found that the semantic memory is located on the left side of the prefrontal cortex and the episodic memory was on the right

Tulving et al 1994.

  • He linked the left side with episodic memories instead.

This challenges any neurophysiological evidence to support types of memory as there is poor agreement on where each types is located.

Real world application.

  • As people get older there memory tends to get worst.
  • They found that episodic memories are often effected the most.
  • Sylvie Belleville et al 2006 was able to create an intervention to improve episodic memories in older people.

Shows that distinguishing between types of LTM enables specific treatments to be developed.

Same or different.

Tulving 2002

Claimed that the episodic memory is a 'specialised subcategory' of the sematic memory. Meaning... they are basically the same store.

Evidence.

After studying people with amnesia he found that is it possible to have a working semantic memory and a damaged episodic but not to have a damaged semantic memory and a working episodic.

Hodges and Patterson 2007.

Found that some people with Alzheimer's disease could not form new episodic memories but not semantic memories.