lecture 6 - sleep and memory Flashcards
what does sleep help?
- helps recover information
- prevents forgetting.
- integrates new information with existing knowledge.
Jenkins and Dallenbach 1924
Two Ss learn lists of 10 nonsense syllables until complete mastery.
Re-tested in free recall after a varying time interval (1,2,4, and 8 hes) filled in with sleep or wake.
Sleeping protects against forgetting.
‘the results of our study as a whole indicate that forgetting is not so much a matter of the decay of old impressions and associations as it is a matter of the interference, inhibition, or obliteration of the old by the new’
However, absence of interference is not the whole story: actual role for memory consolidation.
Plihal and Born 1997
Effects of early and late nocturnal sleep on declarative and procedural memory.
Tested the differential effect of sleep composition.
Compared declarative and procedural memory.
Double dissociation: declarative memory promoted by slow wave sleep; motor skills improved by REM sleep.
paybe et al 2012
Learning of related -’circus-down’- or unrelated pairs -’cactus-brick’- using study test cycles with feedback until 24 out of 40 correct.
After 12 hrs, better performance for the sleep group, only for unrelated pairs
The ‘sleep-first’ effect
Temporal gradient a retroactive facilitation: after 24 hrs, better recall for those who slept first.
Both absence of interference and system consolidation during SWS could be behind the effect.
neural replay
Done mostly unconsciously, through some o it could reach consciousness.
Allows other brain regions to learn the information in question.
Slow-wave sleep (SWS) appears as a key window.
Slow-wave sleep and neural replay -
According to the model of systems consolidation put forward by Born and Wilhelm (2013), during slow-wave sleep, slow oscillations occurring in neocortical regions constitutes a signal sent via the thalamus to the hippocampus to reactivate hippocampal memories. As can bee seen in Fig. 3, neocortical oscillations drive thalamo-corticol spindles, which themselves drive spindle-ripple events in the hippocampus: the alignment between levels is strong and controlled always by the troughs at the level immediately above. In nutshell, the neocortex is saying to the hippocampus: “alright, now is a good time to tell me what you know!”.
‘cuing’ rash et al –2007
Cured reactivation using an odour also present during the learning phase.
Used spatial memory as skill.
Re-exposure to associated odour during SWS reactivated hippocampal areas active during learning.
Also led to enhanced memory performance the next day.
sleep and previously inaccessible memories.
Sleep makes previously inaccessible memories accessible.
sleep and extraction
Sleep promotes gist extraction.
Sleep strengthens associations between individual memory elements and fills in the gaps.
