Types of long-term memory - Topic 3

LTM

• The capacity of the LTM is massive

• it is incredibly robust and can survive periods of unconsciousness, anaesthesia, and comas

implicit and explicit LTM

• Implicit LTM - previous experiences aid the performance of a task without conscious awareness of these previous experiences

• procedural memory (skills learnt and procedures)

• non-verbal

• emotionally and somatically based

• robust - may last a lifetime even without further practice

explicit LTM - information that you have to consciously think about

• verbal

• information and experience-based

• fades when you don’t recall

types of LTM

• procedural memory - memory for skills and procedures such as tying a shoelace, picking up a pen

• Automatic and unconscious - implicit and non-declarative

• resistant to forgetting

• brain area - linked to cerebrum and motor cortex

• example - riding a bike, playing the piano

  declarative: memory for facts split into 2:

• episodic memory - Personal events and experiences (happened in an individual’s life)

• explicit/declarative - you consciously recall it

• requires conscious effort to call

• Includes context (time, place) and emotions.

• time-stamped (you remember when things happened)

• brain area - linked to the hippocampus and frontal lobe

• Example: Remembering your first day at school

• semantic memory - factual information such as names of objects and meanings of words

• Knowledge of facts, concepts, and meanings.

• Not tied to personal experience.

• not time-stamped (don’t usually remember when you learned it)

• explicit - have to consciously think about it

• less personal and more about shared knowledge

• brain area - linked to the temporal lobe

• Example: Knowing what a psychological term means.

properties of types of LTM

• different types of memory encoded in different ways

• episodic memory is stored much easier than semantic

• procedural is more resistant to decay compared to episodic and semantic

evaluations for different types of LTM

• ✅Point: Case studies provide strong support for the idea that long-term memory is divided into separate stores

Evidence: One example is Clive Wearing, a musician who suffered brain damage that left him with severe amnesia. While his episodic memory was almost destroyed, he could still play the piano and remember how to conduct music, showing that his procedural memory was still intact.

Explanation: This demonstrates that different types of long-term memory are stored in different areas of the brain. If LTM were a single store, we would expect all forms of memory to be equally affected by brain damage.

Link: Therefore, Clive Wearing’s case study supports the theory that long-term memory is not unitary and consists of separate systems such as episodic and procedural memory.

• ✅Point: Brain imaging research provides scientific evidence for different types of long-term memory.

  Evidence: Tulving et al. (1994) used PET scans to study participants while they performed memory tasks involving either episodic or semantic memories. The results showed that episodic memories activated the right prefrontal cortex, while semantic memories activated the left prefrontal cortex.

  Explanation: These findings support the idea that episodic and semantic memory are located in different areas of the brain, providing biological evidence for the separation of memory stores.

  Link: Therefore, Tulving’s study strengthens the validity of the theory that long-term memory is made up of multiple, distinct types.

❌Point: A weakness of the theory of different types of long-term memory is that evidence from case studies may lack generalisability.

Evidence: For example, much of the support for separate memory stores comes from studying individuals like Clive Wearing or HM, who suffered rare and severe brain damage.

Explanation: While these cases offer valuable insight, they are highly unusual and may not reflect how memory works in the general population. This means we cannot be sure that the conclusions drawn from these individuals apply to everyone, especially people with healthy brains.

Link: Therefore, although case studies provide important evidence, they limit the external validity of the theory that LTM is divided into separate types.