Cognitive⚙️ • Baddeley's Study (1966b) Flashcards
What type of experiment was this study?
A laboratory experiment
What was the Aim of the study?
To find out if LTM encodes acoustically (based on sound) or semantically (based on meaning). This is done by giving participants word lists that are similar in the way they sound (acoustic) or their meaning (semantic); if the participants struggle to recall the word order, it suggests LTM is confused by the similarity which means that this is how LTM tends to encode.
- To determine how long-term memory is affected by semantic & acoustic encoding
What was the design for this experiment?
An independent groups design (2 different groups)
What was the type of sample for the study?
Volunteer sample
What was the sample for the study?
- 75 Participants in total
- All young servicemen (e.g. army etc…)
- Sample was initially 75, a hearing test was given before the procedure to ensure all results would be valid as word lists were played aloud - 3 participants’ results were removed as a result of this
What is the Independent Variable for the study?
(CHANGE)
The study had several IVs.
(1) Acoustically similar word list or acoustically dissimilar (LIST A & B)
(2) semantically similar word list or semantically dissimilar (LIST C & D)
(3) performance before 15 minutes “forgetting” delay and performance after (Before & After the 20 minuet gap/ unrelated task)
What was the Dependent Variable for the study?
(MEASURE)
Score on a recall test of 10 words; words must be recalled in the correct order
What was the Procedure for the study?
- There were four separate groups, each presented with a list of words each and all required to learn each list (types of words depended on list ⬇️)
- Each list was presented aloud on a tape, one word every 3 seconds
- Participants had 40 seconds to write down as many of the 10 words that they could recall in the exact order they heard them - this was repeated 4 times (ENGAGING STM)
- Each Participant then spent 20 minuets on an unrelated task: recalling sequences of 8 digits, after this time they were asked to try to recall the 10 words again in the order (ENGAGING LTM)
What were the Results for the study?
- Recall of LIST A was consitently lower than LIST B in the first trial (STM engaged)
- Recall on test after 20 minuets, there was no significant forgetting of words in the acoustically similar lists (A), but there was in the dissimilar list (B) (LTM engaged)
- There were no significant differences in recall of the two semantic lists (C & D) on the first trials (STM engaged)
- In the 20 minuet recall test there was a significant ammount of forgetting in both the semantically similar and semantically dissimilar lists (LTM engaged)
What was the Conclusion for the study?
The conclusion was not expected given the aim of the study and results given by other studies at the time.
* Perfomance on** LIST A** was the only list to show no forgetting in the LTM (on 20 minuet test), contrasingly suggesting that the encoding for LTM is acoustic, not semantic - contratsing prior beliefs and other studies
What is the Generalisability of the study?
- Large sample of 75 meas that any anomalies (The 3 audiably impared individuals) will be averaged out due to sample being so big - therfore meaning sample can safely be generalised to the wider population
- As its only around 15-20 people per list/ group, its they are less representative as its a smaller sample size and anomalies can easily skew
- Volunteer sample may have attracted individuals who are particularly good at memory tests, therefore the sample may not have been representative of generic levels of recall in general population
What is the Reliability of the study?
- Standardised procedures (All participants in same lists hearing exaclty same words, in same order, said by same person, for the same ammount of time (3 seconds), in same intonation as it was a tape) means easy replication and therefore infers high reliability
What is the Application of the study?
- Application of this study alongside the additional studies Baddely conducted after lead him to work with Hitch to apply research and eventually develop the Working Memory Model
- Application in terms of revision methods - If LTM encodes semantically, then it makes sense to revise using mindmaps/ flashcards as they convey/ use meaning
What is the Validity of the study?
- Low ecological validity as it was a laboratory experiment - the reading of words in specific order alongside the task given to identically recall them was artificial and doesnt reflect recall in the real world
- Low Population validity - the sample consisted of British volunteers, inferring the sample was ethnocentric and therefore not representative of the wider population or the recall ability of non-British individuals
- Interal validity - due to standardisation and laboratory setting, there was control over extraneous variables, meaning the rates of recall were not influenced by other factors or variables - deeming results valid
What were the Ethics of the study?
There are no ethical concerns or issues with the experiment
* It was volunteer sample so participants would have intenionally been involving themselves so it is assumed informed consent was given
* The activity was not damaging by any means and did not leave any sort of psychological impact or harm
