Endel Tulving (1985) was one of the first psychologist to realise that the multi store model
view of the long-term memory was too simplistic and inflexible. This is because it describes
both short term and long term memory as single unitary stores. Tulving proposed there are
3 long term memory stores episodic memory, semantic memory and procedural memory.
Each of these 3 different types of memory have their own unique characteristics and contain
quite different types of information.
Episodic memory is a long-term memory store for personal events and ‘episodes’ in our
lives. Episodic memory is based on our personal experience and is like a diary, a record of
daily happenings. Memories that are episodic are ‘time-stamped’, so you remember when
they happened: recently, now or last week. Furthermore, you can recall the context
surrounding the event, for example what you were doing before and after the event. You
may also be able to recall associated emotions recalled at the time. Moreover, your memory
of a single event will include several elements, such as people, places, object, behaviour and
all of them are linked to produce a single memory.
Semantic memory contains our general knowledge ‘knowing that.’ For example, knowing
the age children go to school is at 4. Semantic memory contains knowledge also facts about
the world, which is shared with everyone not just you personally. Semantic memories may
relate to functions of objects, how to behave appropriately and abstract concepts such as
maths. Moreover, semantic memories are not ‘time stamped’ so you don’t remember when
you first learned about it. Semantic memories contain a vast collection of material which
given its nature is constantly added to, this memory has been likened to combination of an
encyclopaedia and a dictionary. Semantic memories usually begin as episodic memories and
theres a gradual shift from episodic to semantic memories. This is because the memory
loses its association to events.
The finally long term memory is procedural memory ‘knowing how.’ This memory is
concerned with skills, such as knowing how to tie a shoe lace or driving a car. Procedural
memory is usually required through repetition and practice and it is about remembering
how to do something rather than knowing the rules of what to do. We are less aware of
these memories as they are automatic and often if you think about procedural memories it
prevents you acting on them. It is important that our procedural memories are automatic so
that we can focus our attention on other tasks. This memory is different from the other two
as it is explicit ‘knowing how’ rather than declarative ‘knowing that.’
A strength of the long term is research from brain scans support the types of LTMs stored in
various parts of the brain. For example, Tulving et al (1994) got their participants to perform
various memory tasks while their brain was scanned using PET scanner. They found the
episodic and semantic memories were both recalled from an area of the brain known as the
prefrontal cortex. This area of the brain is divided into two, the left prefrontal cortex was
involved in recalling semantic memories and the right prefrontal cortex involved in recalling
episodic memories. Therefore, this supports the view that there are different types of LTM
as different areas of the brain are active when different types of LTM are active.