Sleep + memory - Penny Lewis Flashcards
(Lewis et. al. TiCS 2018):
What is the title of the study?
(Lewis et. al. TiCS 2018):
How memory replay in sleep boosts creative problem solving.
(Lewis et. al. TiCS 2018):
Who was this study by?
(Lewis et. al. TiCS 2018):
Penny Lewis & NaPS
Neuroscience and Psychology of Sleep
(background):
Describe Wallas’ 4 stage model for the creative process.
(background):
1926, Graham Wallas had come up with a 4 stage model for the creative process.
- Preparation
Conscious work - Incubation
Problem set aside - Illumination/ Inspiration
Promising idea - Verification
Conscious development and checking of Illumination
(background):
List 3 points that indicate sleep must be important?
(background) :
- 1/3 of your life (as a human)
- Widespread in the animal kingdom
- Adaptations to allow sleep
e.g.
> Many fish must gulp water to pass it through their lungs while they sleep immobile.
> Dolphins sleep with just one hemisphere at a time.
> Hibernating mammals, which actually warm up during hibernation in order to obtain sleep.
(background):
Describe the different stages of sleep recognised by an EEG.
(background):
Stage 1 – light transition phase very similar to wake, just a little slower
Stage 2 characterised by spindles
Stage 3 still has spindles but dominated by slow oscillations
REM looks very similar to wake, but muscle atonia and deeply asleep
You cycle through the sleep
stages around every 90 minutes.
(see slide 6 in relevant powerpoint for graphs)
(background):
In an EEG, what is Rapid Eye Movement (REM) characterised by?
In an EEG, what is Slow Wave Sleep (SWS) characterised by?
(background) :
- In REM the EEG actually looks very similar to wake, although it is also characterised by theta oscillations at around 5 Hz
- SWS is characterised by high amplitude oscillations at about .8 Hz
These oscillations are interleaved throughout the night.
And are thought to have different, and complimentary, impacts on memory and cognition.
(Lewis et. al. TiCS 2018):
How are NREM and REM sleep proposed to be associated with creative thinking?
(Lewis et. al. TiCS 2018):
NREM: Abstraction of emergent structure
‘bird’s eye’
REM: Associative thinking
‘outside the box’
(background):
What is semantic memory?
(background):
Concept-based knowledge unrelated to specific experiences.
e.g.
The sky is blue
Paris is the capitol of France
(background):
How are semantic memories formed?
(background):
One possible origin is episodic memory, and it has been proposed that episodic memories can become semantic through a process of semanticisation.
This is characterised by extraction of gist information or the shared components in a body of knowledge (e.g. I’ve seen the sky hundreds of times, and it was usually bue)
by decontextualisation – I don’t remember the occasion on which I first saw the sky, I just remember it was blue
And some theories suggest that it is characterised by the neuroplasticity such that information which was initially represented in the MTL becomes gradually more cortical – and semantic memory is fully cortical
Lewis’ goal is to examine the process of semanticisation, and particularly the role of sleep in this process.
(Lewis et. al. TiCS 2018):
List the 4 main areas of her work.
(Lewis et. al. TiCS 2018):
- Gist abstraction
- Integration into existing knowledge
- Indirect inferences (REM)
- BiOtA model and Creativity
(Lewis et. al. TiCS 2018):
What idea did Lewis use to examine gist extraction and sleep?
(Lewis et. al. TiCS 2018):
(Gist abstraction)
Statistical learning to look at gist extraction, because it requires integration across multiple examples.
For example,
Similarly, there is a probability that the sea turtle will swim L or R in its predatory search. If you just watch it for a little while it’s choices may appear random – the pattern can only be detected by integrating across lots of instances.
Lewis argued that this type of integration is an example of gist extraction. Because we were interested in gist extraction and sleep, Simon Durrant (a postdoci in my lab) therefore decided to examine the impact of sleep upon statistical learning.
> Learning about probabilistic patterns
> Can only be detected by integrating across many experiences
> Good model for gist abstraction
Q1: Is this facilitated by sleep?
Q2: Does sleep influence the neural coding?
(Lewis et. al. TiCS 2018):
What method did Lewis use to examine statistical learning?
(Lewis et. al. TiCS 2018):
(Gist abstraction)
18 Pps / group
Played 7 tones in a sequence.
Tones sound like they’re in a random order but there’s a hidden structure.
(see slide 15 + 16 in relevant powerpoint for audio and rest of method)
(see slide 17 + 18 for results)
(background):
Describe (Tse et. al. 2007; 2011 Science) work on schemas.
(background):
(Integration into existing knowledge)
(Tse et. al. 2007; 2011 Science)
- Information is learned better if it fits a schema (schema effect)
- Such information is also consolidated faster
TO TEST THIS:
(see slide 21 - 24 in relevant powerpoint slide)
(Lewis et. al. TiCS 2018):
(Lewis et. al. TiCS 2018):
Information dump:
SWS predicts abstraction and disengagement of the hippocampus in the auditory statistical learning task.
Sleep spindles predict integration into a schema and disengagement of the hippocampus for schema linked memories.
keep going :) the exams will be over soon, you HAVE to do your best.
