There is evidence from brain scans that support the existence of different types of LTM.
For example, PET scans show us that different parts of the brain are active when the different types of LTM are being used.
Episodic memory is associated with the hippocampus and temporal lobe, semantic memory is associated with the temporallobe and the procedural memory is associated with the cerebellum and basal ganglia.
This means that the claim that there are different types of LTM are valid as there are physical neural differences.
strength
Case studies of amnesiac support the existence of different types of LTM
For example Clive Wearing had a severe case of amnesia and had trouble remembering events that happened to him after his amnesia, however he had procedural memory, such as riding a bike.
This shows that Clive's STM was damaged but his LTM was unaffected.
This means that damage to one type of LTM can leave the other unaffected, showing that there are different types of LTM.
Negative
Evidence from case studies may be lacking some corefeatures of a science.
They focus on one individual patient who usually suffered brain damage for example Clive Wearing. As a result you are unable to replicate the results of this unique case to a wider population.
This means we can't really state if the LTM is made up of different components.
Positive
Understanding different types of LTM allows for the development of helpful real life practical applications.
Belleville et al (2006) compared the performance of older people suffering with mildcognitiveimpairment who received memory training with that of a control group who did not. It was found that pps in the experimental condition performed better on a test of episodic memory.
This suggests that being able to identify the type of LTM being used can allow psychologists to create appropriate treatments and improve lives.
strengths of long term memory (3)
practical applications can be developed (Belleville et al)