Encoding in the real world Flashcards
What did Simon and Emmons (1956) do?
They played pts questions and answers every 5 minutes with EEGs to check that they were asleep, subsequent tests found that they performed above chance.
What exactly did Simon and Emmons (1956) find by dividing scores by EEG sleep state?
- awake but relaxed - 80%
- drowsy - 50%
- drowsiness/light sleep transition - 5%
- asleep - no effect
What did Bruce, Evans, Fenwick and Spencer (1970) find?
That when sleeping participants were presented with material then immediately awoken, there was no evidence for memory.
How does sleep play a role in memory?
- Pace-Schott et al. (2003) - we can still remember internal events (i.e. dreams)
- sleep may be important for memory consolidation (Hahn et al., 2006; Paller and Voss, 2004)
What did Levinson (1965) find about memory during anaesthesia?
10 dental surgery patients, staged a mock crisis and one month later hypnotised them - four patients produced almost verbatim reports of the anaesthetist’s comments, four produced partial reports and only two produced no recall.
What are some problems with Levinson (1965)?
- ethics
- no control condition
- suggestibility under hypnosis
- experimenter and hypnotist (Levinson) not blind to hypothesis
- no measure of degree of anaesthesia
Why is it possible that we can encode information while under anaesthetic?
- Anaesthetic may not be total - cocktail issue (anaesthetic, analgesic, and muscle relaxant) - may have not had enough anaesthetic, but enough to forget.
- Different tests of memory may reveal different evidence for memory from anaesthesia.
Define explicit memory.
It requires conscious recollection of prior experiences (free and cued recall, and recognition tests).
Define implicit memory.
Revealed on tasks that do not require reference to a specific episode, e.g. Using word stem completion, word fragment completion or degraded picture naming after priming.
What did Iselin-Chaves et al. (2005) do?
Monitored depth of anaesthesia using EEG bispectral index and had participants listen to two lists of 20 words, each presented 25 times. One word presented every 4 seconds, so 70 minutes of presentation.
Describe the words used by Iselin-Chaves et al. (2005).
They were all 6 letters long, and each shared a stem (first 3 letters) with at least 4 other words.
What procedure did Iselin-Chaves et al. (2005) use to test their subjects’ recall?
Jacoby (1991) process dissociation procedure.
Describe the procedure used by Iselin-Chaves et al. (2005) to test their subjects’ recall.
- inclusion test - produce items from any source
* exclusion test - only produce items that weren’t previously studied.
Describe how process dissociation procedure gives separate measures of explicit and implicit memory.
Probabilities: R = conscious recollection - explicit A = unconscious/automatic memory - implicit Inclusion test = R+A(1-R) Exclusion test = A(1-R) So Explicit = inclusion - exclusion Implicit = exclusion/(1-explicit)
What did Iselin-Chaves et al. (2005) find?
No explicit memory, regardless of depth of anaesthesia.
Some implicit memory, depending on depth of anaesthesia - therefore we can encode new memories while under anaesthesia.
What evidence is there to show that memory for common objects is surprisingly poor?
- Nickerson and Adams (1979) American example
- Richardson (1993), Martin and Jones (1995), and Morton (1967) describe a British example
- Rinck (1999) - related German finding
What is weapon focus (Loftus, 1979; Loftus, Loftus and Messo, 1987)?
The idea that in a stressful event such as a crime, one might have clear memory for central information but impaired memory for peripheral information, due to arousal and what one attends to at the time.
Who demonstrated weapon focus experimentally?
Christianson and Loftus (1991).
What has been demonstrated with regard to weapon focus?
Chapman and Underwood (1998) - change in eye movements in stressful situations. Memory changes can be more subtle (Wessel et al., 2000).
What did Chase and Ericsson (1981) do?
Tested S.F., gave him a lot of practice at remembering digits (increased digit span from 10 to 80). Claimed improvement was based on chunking.
Does practicing short term memory tasks improve stm generally?
No - Chase and Ericsson (1981) found that SF’s letter span was still at 6 items when he could memorise 80 digits.
