Lecture 4: Impasse and restructuring Flashcards
Definition of creativity
Problem solving which requires originality and effectiveness (originality alone is not enough)
How can we solve problems without creativity?
Forward search: Try all options
Hill climbing: Do a few moves at a time and feel if we get warmer to the answer
Problem reduction: Smaller and smaller chunks
What is type 1 in the dual process theory?
Intuition and automatic - does NOT load working memory.
It is more accurate when we have gathered a lot of data with reliable and fast feedback
What is type 2 in the dual process theory?
Explicit, rule-based, rational, and analytic - NOT insight
Requires wm
Slow and sequential
Reasons according to logical standards
Different stages of creativity and whether they use type 1 or type 2 processing?
- Prep: type 2
- Incubation: type 1
- Illumination: type 1
- Verification: type 2
Results from reviews of the impacts of incubation?
Out of 39, 26 (75%) found significant benefits of incubation across a range of tasks
They found that longer incubation (about 30 mins) is better than shorter incubation (e.g 5 mins)
Also found 24 hours is good
What are the different views asking whether restructuring is conscious?
Gestalt: NOT conscious: restructuring is a distinct process different from type 2 (bulk of literature agrees with this
Weisberg: Restructuring can arise from normal conscious processes of search and problem analysis
What is the evidence for Gestalt view of restructuring?
Gestalt view: separate from type 2
If it does not rely on WM, tasks that impair working memory will not make a difference to problem-solving
- Experiments, where ppts have had alcohol (impairs WM), found that it facilitates RAT-solving tasks (Jarasz)
- Experiments with participants with focal brain damage to the lateral frontal cortex (involved in WM) were better at matchsticks task than a control (Reverberi et al)
What is the representational change theory?
3 different ways we can restructure concepts in the brain to help us problem solve
1.Elaboration - Add new info to the problem representation
- Constraint relaxation - assumed constraints on the problem representation are removed (e.g 9 dot task)
- Reencoding - Part of the problem is interpreted differently to overcome functional fixitidy e.g box can be used for something else
How are episodic memories formed in the brain?
Hippocampal contribution to memories is diminished when the consolidation process is finished
Disruption of the consolidation process leads to poorly formed memories - we forget these
How does incubation faciliate memory processes?
Incubation period: memories are transformed from the hippocampus to other areas in the cortex
Means we remember the gist of memories but forget specific details (become semantic)
Patient HM
Had his hippocampus removed due to epilepsy
No episodic memory after the removal e.g cannot find new home / learn new names
He is severe retrograde amnesia (cannot form new memories)
He has mild retrograde amnesia (cannot remember some memories that happened just before the removal of the hippocampus)
What does patient HM tell us about the involvement of the hippocampus in memories?
Some memories, which were not already transferred from the hippocampus to other brain areas were lost following the lesion.
Memories which were already transferred were not lost
What is the standard model of consolidation?
The hippocampus is the hub which links together the cortical components in a new memory
Over time, direct connections between neocortical representations build up
Connections via the hippocampus simultaneously weaken until the hippocampus is no longer needed / involved
What studies show the hippocampus weakens over time?
Takashima et al
PPts learn info
Then recall in a scanner: 1, 30 or 90 days later
Found that hippocampus activity reduced over time
(Ventral medial PFC increased)
How do memories change over time?
We forget, blur, false memories and integrate memories (form novel connections) over time
What happens in the brain when memories change?
Do not really know
We know they are activated offline
Get rats to do a task over and over again
Can see as they move throughout location, specific place cells fire
When they are offline ( inc asleep), can see these cells firing in the same order, reverse order
Even evidence that they learn a novel route - especially when food is involved
= recombining and restructuring the memories
JC: Wagner et al study aim
To see if mental restructuring that leads to a sudden insight in explicit knowledge is impacted by sleep.
Wagner et al method:
Ps= number reduction task - form a string of digits into a new string. There was a hidden rule.
All ppts first trained on 3 task blocks to induce mental representations
Training was followed by
1. nocturnal sleep
2. nocturnal wakefulness
3. Daytime wakefulness
Wagner et al results:
Sleep = more than doubled the probability of gaining insight into the hidden rule compared to wakefulness (59% compared to 22% in either wake group)
Reaction times= RT decreased in all groups but significant differences between solvers (marginal speeding) and nonsolvers (profound speeding) in sleep condition
Sleep had a larger impact on RT for non-solvers = restructuring originates from an effect of memory representations different from those underlying procedural learning
Wagner et als additional experiment?
To ensure the influence of sleep was on memory representations, ppts did the same task again but without training
Either tested in the morning (after sleep) or evening (after wakefulness)
Found that 5/20 gained insight = the same level as wake in the OG experiment
JC: Wu et al study aim
Aimed to identify the neural underpinnings of chunk decomposition (breaking up chunks into their elements to make them available for reorganising)
How does chunk difficulty vary (Wu et al)
- Loose vs tight (loose = perceptual subcomponents are meaningful themselves / tight = perceptual subcomponents are not meaningful themselves)
- Familiarity (High familiarity = more intimate knowledge increases difficulty because components of highly familiar chunks are more closely associated with each other)
Wu et al study design:
200 existing Chinese characters with 2 different chunk tightness levels (familiar-loose / familiar-tight)
200 pseudo Chinese characters with 2 different chunk tightness (unfamiliar- loose / unfamiliar-tight)
Had EEG and fMRI
- Ppts decide whether the character existed or not
- Character and ‘the to be removed part’ (stroke) were presented in the middle - on the left was the character without the stroke, on the right was the removed stroke
- Ppts had to judge whether the remaining part of the left character was an existing character without the removed stroke
Wu et als results (behavioural)
Behavioral:
RT was longer for the tight characters than the loose
Ppts were more accurate for loose than tight characters
Wu et al results (brain imaging)
For tight chunks = strong activation in prefrontal areas
For loose chunks = activation in right cingular cortex etc
ERP: amplitude was significantly larger for familiar-tight than all other conditions
Conclusions:
Results revealed that to overcome chunk tightness, frontal and parietal areas need to work together to provide a spatial update of an existing perceptual representation
