PSYC10003 Lecture Notes - Lecture 30: Semantic Memory, Episodic Memory, Autobiographical Memory
12 Jun 2018
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Lecture 30, Tuesday, 17 May 2016
PSYC10003 - MIND, BRAIN & BEHAVIOUR 1
LECTURE 30
LTM & AMNESIA
LONG TERM MEMORY (LTM)
•Long term memory is a memory system that stores vast amounts of info for a very long time,
possibly permanently. Models show it comprises of two systems: declarative and procedural
memory.
ORGANISATION OF LTM
DECLARATIVE (EXPLICIT) MEMORY
•Declarative memory is the long term memory of specific facts and events, most which can be
stated. (Eg. identifying a type of flower, remembering the date of the Beijing Olympics)
•Also known as explicit memory. It’s knowledge that tis consciously recalled; who, what, how,
when, where, why.
•Explicit memory occurs when info is consciously or intentionally retrieved and stated. (explicit)
‣(Eg. remembering a PIN number, recalling the colours on the Italian flag)
‣Also called declarative memory as the info can be consciously retrieved and ‘declared’
•Procedural memory is ‘knowing how’ and declarative memory is ‘knowing what’.
Endel Tulving (1972)
•Proposed that the two sub systems of declarative memory are episodic and semantic memory.
‣Episodic memory (autobiographical memory) is the declarative memory of personally
experienced events. It includes;
‣When/where memories
‣Contextualised memory
‣‘mental time travel’.
‣Semantic memory is the declarative memory of facts or knowledge about the world. It
includes;
‣Facts learned in school
‣Everyday facts and general knowledge
‣Rules/laws
‣Words
‣Individual areas of expertise (Harry Potter)
‣What/why memories
‣Abstract knowledge.
•Memories can be both semantic and episodic (Eg. remembering the 2012 Olympics were held in
London as a fact is semantic, but remembering because you were at those Olympics is episodic)
•Episodic memory has a context. According to Tulving, when we recollect details about an event
we engage in a kind of ‘mental time travel’ to recover the contextual details associated with the
event (when, where, who, etc).
•In contrast when we retrieve semantic knowledge, the memory is not bound to the specific
context in which the knowledge was acquired. This is because we accumulate semantic knowledge
across multiple experiences in a variety of contexts.
•Tests that assess declarative memory are referred to as explicit memory tests because they require
the retrieval of an explicit (consciously reportable) description of knowledge from memory.
NON-DECLARATIVE (IMPLICIT, PROCEDURAL) MEMORY
•Implicit memory (or non-declarative memory) occurs when remembering something does not
involve conscious or intentional retrieval, but the memory can be expressed through actions or
behaviour. (procedural)
‣Memory without awareness (implicit) (Eg. using chopsticks or a knife and fork, ability to
produce a sentence, to speak, to walk, includes cognitive skills like reading or arithmetic)
Lecture 30, Tuesday, 17 May 2016
PSYC10003 - MIND, BRAIN & BEHAVIOUR 1
‣Not dependent on hippocampal structures.
‣Conditioned (learned) emotional responses involve implicit memory.
‣Term ‘implicit’ used because memory can be implied from observable responses.
‣Also called non-declarative as implicit memories are often difficult to vocalise.
•Non-declarative memory (implicit memory) refers to forms of long-term memory that are
expressed as a change in behavior without conscious recollection. Tests of non-declarative
memory are referred to as implicit memory tests. Such tests do not require description of the
contents of memory, but rather reveal memory processes indirectly (implicitly) through observed
changes in performance. For example, the gradual perfection of a motor skill reflects implicit
memory.
•Whether or not I can recall learning something in the past, the fact that I did learn the thing
means that I can do it and will improve at it.
•Procedural memory (skill/habit memory) is the long term memory of motor & cognitive skills
that have been learned previously.
‣Little conscious awareness is required to retrieve the skill.
‣Procedural memories are often difficult to put into words.
•Evidence gained from studies conducted with amnesic patients that shows that the two forms of
memory (declarative and non-declarative) are dissociable, that is, that they rely on different
neurological networks in the brain.
•Non-declarative memory is not dependent on hippocampal structures, while declarative memory
is.
•Declarative memory is dependent on the structures of the medial temporal lobes (MTL), including
the hippocampus, whereas non-declarative memories can be encoded, stored and retrieved even
when the hippocampus and associated areas in the MTL has been removed.
•Priming is a form of non-declarative memory demonstrated by a change in the ability to identify
a stimulus as a result of prior exposure to that stimulus or a related stimulus.
•Repeated priming; Eg. Prior exposure to a word in a lexical decision task will make the word
easier to respond to next time it is encountered.
•Associative/semantic priming; Eg. The prior presentation of the word ‘nurse’ facilitates
subsequent identification of the word ‘doctor’.
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