Types Of Long-Term Memory.

Types Of Long-Term Memory.

1. One criticism of the multi-store model of memory was that it presented an oversimplified view of long-term memory.

   • In an elaboration of long-term memory, Tulving (1972) proposed a distinction between different types of long-term memory.

2. Types of Long-Term Memory.

   • Episodic Memory.
     • The long-term memory for events or episodes which we have experienced ourselves, or which we have heard about from another source.
       • E.g. would be remembering the events of our first day at college, or from a day out at the seaside with friends.
       • Such memories are usually linked in our memory to a particular time and place.
   • Semantic Memory.
     • The long-term memory for information about the world or world knowledge. This includes knowledge about the meanings of words and general knowledge.
       • E.g. Would be the knowledge that grass is green, recalling the date of your mother's birthday, or knowing that a giraffe is an animal with a long neck.
       • Such semantic memories can be used without reference to when and where the information was learned. Indeed, very rarely do we know exactly when we first learned such information.
   • Both episodic and semantic memory can be inspected consciously and are described by Cohen and Squire (1980) as declarative, meaning that they can be put into words quite easily.
     • E.g. You can tell someone what happened on your first day at college and you can tell someone what a giraffe is like.
     • These two types of memory are very closely linked.
       • E.g. The memory for events on your first day at college can become integrated into your semantic memory or general knowledge about college.
     • Episodic memory and semantic memory are sometimes referred to as 'knowing that' memories.
       • Procedural memory is sometimes referred to as 'knowing how' memory.
         • Episodic and semantic are declarative and involve 'knowing that...' Procedural is non-declarative and involves 'knowing how...'
     • Research Study: Tulving (1989).
   • Procedural Memory.
     • A further type of long-term memory was proposed by Cohen and Squire in 1980. This is a motor- or action-based memory.
       • E.g. Would include the memory of how to ride a bike or how to swim.
       • Unlike episodic and semantic memory, procedural memory cannot be consciously inspected and is non-declarative, meaning that it is very difficult to put into words.
         • E.g. Trying to explain breast stroke to someone in word. In your explanation you are not allowed to move your arms or legs, and you cannot refer to frogs.

3. Patients with amnesia provide evidence for the distinction between declarative and procedural memory.

   • Research Study: Corkin (1968).
   • Such patients often have problems remembering episodic and semantic information they encounter after the onset of their amnesia, although their memory for events and knowledge acquired before the onset of amnesia tends to remain intact.
     • In other words, it appears that their ability to retain any new declarative information is impaired.
     • However, these amnesic patients seem to be able to learn and remember new motor skills, suggesting that their ability to acquire procedural knowledge remains intact (Cohen 1984).
   • Evidence for the opposite effects has been reported in patients with the brain disease known as Huntington's disease.
     • Huntington's patients have problems learning new motor skills, so probably have some damage to their procedural memory system. However they can acquire declarative knowledge (Heindel et al. 1988).
       • Together with the findings of Corkin (1968), this pattern suggests that there are different systems underlying procedural and declarative memory.

4. Some evidence to support the existence of separate and distinct long-term memory stores has come from studies monitoring blood flow in the brains of participants while they complete different types of memory tasks.

5. The Distinction Between Different Types of Long-Term Memory.

   • It seems sensible to make a clear distinction between episodic, semantic and procedural memories in terms of their content, as each type of memory holds a different type of information.
   • Exactly how much episodic memory and semantic memory involve different brain structures and processes is unclear, supported by limited evidence, such as the study by Tulving (1989).
   • Some researchers (E.g. Medin et al. 2001) suggest that episodic memory and semantic memory are part of the same system.
   • Evidence from clinical studies indicates that declarative memory and procedural memory rely on different encoding systems and brain structures.
   • Wheeler et al. (1997) expanded on the distinction between episodic memory and semantic memory by focusing on different thoughts and feelings that are experienced when the two types of memory are recalled. They suggest that episodic memories are associated with the conscious awareness of the self actually experiencing the event. In contrast, the recall of semantic memories involves thinking objectively about something that we know, rather than a conscious recollection.