Long Term Memory - Tulving Flashcards
Long-term Memories
Long term memory is a complex memory store that holds information for a long time, possibly a lifetime. It has unlimited capacity and is encoded semantically. It is divided into three main types: episodic (personal experiences), semantic (facts and knowledge), and procedural (skills and actions). Due to its complexity, it suggests why we may be better at remembering some things, such as places, but not faces.
Concept of Long-term Memory
The idea of long-term memory was first proposed by Atkinson and Shiffrin in their multi-store model of memory, which suggested that memory consists of three stores: sensory, short-term memory and long-term memory. Later, Tulving expanded on this by identifying different types of long-term memories: episodic, semantic and procedural memory.
What are the 3 types of Long-term Memories?
1) Episodic
2) Semantic
3) Procedural
Long-term memory can be further divided into:
- Explicit memory - This involves conscious recall of information. It is also referred to as declarative memory and involves episodic and semantic memory. An example is remembering your last birthday or recalling the capital of France.
2, Implicit Memory - This is unconscious and does not require deliberate effort to recall. It is also referred to as non-declarative memory and involves procedural memory. An example is riding a bike or typing on a keyboard without consciously thinking about it.
Episodic Memories
Definition: Episodic memory is a type of long-term memory that stores personal experiences and events.
Key features:
1. Explicit memory - They take a conscious effort to recall.
2. Time-stamped - They are linked to specific times and places.
3. Includes details - Such as emotions, people, locations and sensory experiences.
Episodic memories can be split further into:
1. Autobiographical episodic memory - Memories of specific events of one’s life.
2. Flashbulb episodic memory - Detailed autobiographical episodic memories that are permanently stored in the long-term memory component when first experienced as they are of emotional/historical significance in that person’s life.
3. Experimental episodic memory - Where learning a fact has been associated with a memory of a specific life event when it was learnt.
Brain area involved:
1. Hippocampus - Forms episodic memories.
2. Prefrontal cortex - Retrieves episodic memories.
Semantic Memories
Definition: Semantic memory is a type of long-term memory responsible for storing general knowledge and facts that is not linked to personal experiences.
Key features:
1. Explicit memory - They are consciously recalled and information is used when it is needed.
2. Not time-stamped - You don’t remember when or where you learned those facts therefore it is different to episodic memory in this way.
Brain area involved:
1. Temporal lobe - Stores and processes general knowledge.
2. Left prefrontal cortex - Primarily involved in semantic memory.
Procedural Memories
Definition: Procedural memory is a type of long-term memory that stores information about how to perform motor skills and actions.
Key features:
1. Implicit memory - These skills and actions aren’t consciously thought of while performing them. They become automatic over time.
2. Skill-based memories - Procedural memory stores skills and habits that are learned through practice and repetition.
3. Hard to explain - It is often difficult to describe these skills in words because they become automatic.
4. Distinct from episodic and semantic memory - It often remains intact even when other memories are lost.
Brain areas involved:
1. Basal ganglia and cerebellum - Primarily involved in procedural memory. They help with motor control and coordination, which is essential for procedural tasks.
2. Motor cortex - Also plays a role in the execution of procedural actions.
Strength
Point: There is strong clinical evidence supporting the existence of different types of long-term memory.
Evidence: Case studies of amnesic patients, such as Clive Wearing and HM, provide compelling evidence to support this. Both suffered from severe impairment to their episodic memory, meaning that they could not recall personal events from their life. However, their semantic memory remained relatively intact. For example, HM could not remember stroking a dog moments earlier but still understood what a dog was. In addition, their procedural memory was unaffected, as Clive Wearing could still play the piano, and both could perform learned skills, such as tying their shoelaces.
Justification: This supports the idea that episodic, semantic and procedural memory are separate components within long-term memory, as damage to this store does not necessarily impact all types of long-term memory. If long-term memory was a single, unified system, we would expect all types of memory to be equally impaired.
Implication: As a result, this strengthens the validity of the theory that long-term memory consists of distinct stores as it provides evidence through the use of real-life amnesiac patients.
Counterargument: However, while cases like Clive Wearing and HM provide strong evidence for separate types of long-term memory, they have limitations in generalisability due to their idiographic nature.
Evidence: These studies are based on unique cases of brain damage, meaning their memory deficits may not reflect how memory works in the general population. For example, Clive Wearing’s amnesia was caused by a viral infection, whilst HM’s amnesia was due to surgery, making it difficult to determine if their memory impairments were due to the same underlying causes.
Justification: As these are individual cases of brain damage, we cannot conclusively say that episodic, semantic and procedural memory are separate aspects of long-term memory in every individual. It is possible that memory functions act as a more interconnected system, rather than being stringent stores.
Implication: Consequently, this reduces the validity of using clinical evidence alone to support separate long-term memory as it doesn’t reflect how memory works amongst the general populations, only considering individuals who have suffered some form alteration to their brain.
Strength
Weakness
counter-argument: however, there is conflicting neuroimaging evidence.
evidence: Buckner and Petersen found that semantic memory is located on the left of the prefrontal cortex, whereas the episodic is on the right. Other studies have found the memory stores located the other way around.
justification: this demonstrates that although there are distinct long term memories, the exact location of where they are coordinated in the brain is unknown due to contrasting evidence.
implication: this inconsistent neuroimaging evidence is therefore an issue as it doesn’t enable us to understand the different types of long term memories more comprehensively, hence this is a weakness of the different types of long term memories.
Weakness
point: a limitation of research into the different types of long term memories is that it heavily relies on case studies.
evidence: an example is the case of Clive Wearing and HM who both suffered from amnesia. The use of ideographic research in this way allows researchers to study memory in a way that would not be possible experimentally. However, there are problems generalising the findings of these clinical case studies with one or few individuals to the wider population. There could be other undisclosed aspects of long term memory that weren’t taken into consideration before theorising about what it comprised because research concerning it was heavily built on case studies.
justification: this suggests that information from these case studies are simply not applicable to a wider population as it is unrepresentative.
implication: therefore, this is a weakness of the different types of long term memory.
