types of LTM Flashcards
who proposed the 3 types of LTM
Tulving
-Semantic, procedural, episodic
Semantic memory
This store contains our shared knowledge of the world. It has been likened to a combination of an encyclopaedia and a dictionary. So it includes knowledge of such things as: how to apply to university, what an orange tastes like, what zombies like for dinner and the meaning of words.
This last one is important. Your semantic memory contains your knowledge of an impressive number of concepts such as ‘animals, love’ and ‘Frozen.
These memories are not ‘time-stamped. We don’t usually remember when we first heard about the new Frozen film, for example. Semantic knowledge is less personal and more about facts we all share. It contains an immense collection of material which, given its nature, is constantly being added to. According to Tulving, it is less vulnerable to distortion and forgetting than episodic memory.Also need to be recalled consciously.-conscious effort.
procedural memory
This is our memory for actions or skills, or basically how we do things. We can recall these memories without conscious awareness or much effort (eventually). A good example is driving a car. Our ability to do this becomes automatic through practice. We change gear without having to recall how. We indicate left or right without even realising we’ve done so.
These are the sorts of skills we might even find quite hard to explain to someone else. If you try to describe what you are doing as you drive the car, the task may well become more difficult.
episodic memory
episodic memory refers to our ability to recall events (enisodes) from our lives This has been likened to a diary, a record of daily personal experiences. Some examples are: your most recent visit to the dentist, a gig you went to last week, the psychology class you had yesterday, the breakfast you ate this morning, and so on. These memories are complex.
first of all, they are time-stamped’ - in other words you remember when they happened as well as what happened. Episodic memories also store information about how events relate to each other in time.
Second, your memory of a single episode will include several elements, such as people and places, objects and behaviours. All of these memories are interwoven to produce a single memory.
Third, you have to make a conscious effort to recall episodic memories. You do this quickly, but you are still aware that you are searching for your memory of what happened when you went to the dentist.
strength-research support
One strength is evidence from the famous case studies of HM (Henry Molaison) and Clive Wearing.
Episodic memory in both men was severely impaired due to brain damage (caused by an operation and infection respectively). But their semantic memories were relatively unaffected. They still understood the meaning of words. For example, HM could not recall stroking a dog half an hour earlier but he did not need to have the concept of ‘dog’ explained to him. Their procedural memories were also intact.
They both still knew how to walk and speak, and Clive Wearing (a professional musician) knew how to read music, sing and play the piano.
This evidence supports Tulving’s view that there are different memory stores in
LTM - one store can be damaged but other stores are unaffected.
C-Counterpoint Studying people with brain injuries can help researchers to understand how memory is supposed to work normally. But clinical studies are not perfect. A major limitation is that they lack control of variables. The brain injuries experienced by participants were usually unexpected. The researcher had no way of controlling what happened to the participant before or during the injury.
The researcher has no knowledge of the individual’s memory before the damage.
Without this, it is difficult to judge exactly how much worse it is afterwards.
This lack of control limits what clinical studies can tell us about different
types of LTM.
Limitation-conflicting neuroimaging research
One limitation is that there are conflicting research findings linking types of LTM to areas of the brain.
For example, Randy Buckner and Steven Petersen (1996) reviewed evidence regarding the location of semantic and episodic memory. They concluded that semantic memory is located in the left side of the prefrontal cortex and episodic memory on the right. However, other research links the left prefrontal cortex with encoding of episodic memories and the right prefrontal cortex with episodic retrieval (Tulving et al. 1994).
This challenges any neurophysiological evidence to support types of memory as there is poor agreement on where each type might be located.
strength-real life application
Another strength is that understanding types of LTM allows psychologists to help people with memory problems.
For example, as people age, they experience memory loss. But research has shown this seems to be specific to episodic memory - it becomes harder to recall memories of personal events/experiences that occurred relatively recently though past episodic memories remain intact. Sylvie Belleville et al. (2006) devised an intervention to improve episodic memories in older people. The trained participants performed better on a test of episodic memory after training than a control group.
This shows that distinguishing between types of LTM enables specific treatments to be developed.
