Psychology stm and ltm Flashcards
What are the 3 types of experimental designs, and what are their definitions?
independent groups-participants are allocated to separate groups where each group experiences different conditions of the experiment.
Repeated measures-all participants experience multiple conditions of the experiment
Matched pairs-pairs of participants are first matched on variables that may affect the DV, one member of the pair is assigned to condition A and the other to condition B
What’s the coding of STM and LTM? Outline the experiment that suggests this.
The coding of STM is mainly acoustic and the coding of LTM is mainly semantic.
Baddeley made lists of different words (10 in each list) and gave 4 groups of participants to recall.
group 1-acoustically sim
group 2-acoustically dissim
group 3-semantically sim
group 4-semantically dissim
Participants were asked to recall them in the correct order. When participants did this task straight away, the trend was to do worse with acoustically similar words. When other participants did this task after an interval of 20min, they did worse with semantically similar words
What is the duration of STM? Outline the procedure that reinforces this.
Peterson and Peterson tested 24 students in 8 trials. In each trial the students were given a consonant syllable (trigram) to remember and a 3 digit number to count back from. On each trial they were told to stop at varying periods of time eg 3, 6, 9, 12, 15 secs…
After 3 seconds average recall was about 80%, after 18 secs is was about 3%
Petersons findings suggest that STM duration may be around 18 secs, unless rehearsed.
What is the duration of LTM? Outline the study that reinforces this.
Harry Bahrick studied 392 american participants aged between 17-74. High school yearbooks were obtained and recall was tested in various ways including
1)photo rec test consisting of 50 photos, some from the yearbook
2)free recall test, participants recalled all the names from their graduating class
-participants tested within 15 years of graduation were about 90% accurate in photo rec, 60% in free recall
-after 48 years recall declined to about 70% for photo rec, 30% in free recall
This shows that LTM may last up to a lifetime for some, but memory traces can die over time
What is the capacity of STM? Outline the study that reinforces this. (Not Miller)
By using digit span-way of measuring the cap of STM in terms of the max no of digits that can be recalled in the right order
Jacobs measured this. A researcher reads 4 digits and a participant recalls this out loud in the correct order, if they get it right the researcher calls out an additional digit and so on, until the participant gets the order wrong
Jacobs found the mean span was 9.3 items for numbers and 7.3 for letters
What is the capacity of STM and chunking? (Miller)
Miller made observations of everyday practice, noting that things came in 7s. He thought the span of STM is around 7 items +/-2.
Chunking-grouping sets of digits/letters into units or chunks which improves the capacity of STM by attributing meaning to stimuli
What are the 3 different types of LTM and their definitions?
EPISODIC-refers to our ability to recall events (episodes) from our lives. They are time-stamped and declarative.
SEMANTIC-store on our knowledge of the world, the meaning of words, and concept. They aren’t time-stamped and declarative
PROCEDURAL-store for actions/skills, how we do things, and motor skills. Non-declarative over time and not time-stamped
List supporting evidence for different types of LTM
-Case studies like Clive Wearing and -HM support separate types of LTM.
PET scans on the prefrontal cortex by Buckner and Peterson. Semantic mem is located on the left side, and episodic is on the right.
-Belleville worked with elderly people to help improve their episodic memories, this supports the usefulness of LTM
List problems with different stores in LTM.
- Other research suggests that episodic memory is located on the left side of the prefrontal cortex and semantic on the right), suggesting its different for individuals
- Case studies consist of atypical minds so they can’t be generalised to the population
- HM suggests that LTM should also be viewed as non-declarative and declarative stores
What is the difference between a natural exp or a quasi exp?
The natural exp-IV is naturally occurring, often taking advantage of a situation, event, intro to a new law etc.
Quasi exp-IV is naturally occurring and is to do with pre-existing characteristics of the participants
What is a schema?
A mental framework of beliefs and expectations that influence cognitive processing. They are developed from experience.
What is classical conditioning? Explain Pavlov’s research.
-Learning by associating two stimuli together so that we begin to respond to one in the same way as we already respond to the other
Pavlov found that the two stimuli had to be presented close together in time, every time the dogs were presented with food a bell rang. Eventually, even if the dogs weren’t presented with food but the bell rang, they still salivated.
What is operant conditioning?
Involves learning from the consequences of behavior. The behaviour is said to be reinforced consisting of positive reinforcement, negative reinforcement, and punishment.
Outline limitations of MSM
- It’s an oversimplified model
- More than one STM store, not unitary (KF, his phonological loop was damaged but his visuospatial sketchpad was intact) and LTM store (eg. Clive Wearing with an intact procedural and semantic mem but damaged episodic mem)
- Problems with case studies, as they are unique and thus unable to generalise to all
What is generalisability
The extent to which the results from a piece of research can be generalised to the population/natural setting
