Please enable JavaScript.
Coggle requires JavaScript to display documents.
Casey (2011) Behavioural and neural correlates of delay of gratification…
Casey (2011) Behavioural and neural correlates of delay of gratification 40 years later
Ability to resist temptation in favour of long term goals is an essential component of individual, societal and economic success. Appealing situations can reduce control. Delay of gratification depends importantly on cognitive control.
Testing adults
- adults can control their impulses with a marshmallow, but have to use cognitive control with the go/no go task
Testing children
: Marshmallow Test - 600 children between 4-6 years old. Had to wait 15 mins for another one - 2/3 children ate the marshmallow
Cool and Hot systems - Control-related brain circuits, whereas 'hot' system involves desires and emotions linked to emotional brain regions
Ventral Striatum
Area of the basal ganglia neural circuit and is most closely associated with reward and is also part of the brain's emotional centre
Right inferior frontal gyrus
- part of the prefrontal cortex, it is involved in the cognitive control process that helps us to inhibit or delay responses (e.g. go/no go tasks)
Aim
Build on previous research, investigate impulse control at both behavioural level and neural (brain activity) level using MRI, sensitivity to alluring or social cues (happy face)
Resisting temptation: Children who found it diffuicult thought of taste adding to temptation. Children who resisted used cognitive strategies such as 'cooling' the appealing features - cotton ball
Exp 1
Quasi-natural & Longitudinal
IV
whether the pp was a high delayer (could resist) or low delayer (couldn't resist)
DV
performance on impulse control task
Sample
562 4 year olds from Stanford's Bing Nursery School, 155 in 20's, 135 in 30's, 117 in 40's.
59pp - 23 males, 36 females
-
32 high delayers (12m, 20f) and 27 low delayers (11m,16f)
Procedure
Tested lower delayer children to see if still have less control
Tasks
Go/No go task (Male and female stimuli- 500ms)
Cool task
'go'
when see male face
'no go'
when female
Hot task
'go'
when happy face
'no go'
when sad face
120 go,40 no go
Findings
1 No significant difference between high and low delayers
Results
for high and low delayers
1 - Performed similar accuracy with go trials
2 - Low delayers made more errors than high delayers on 'no go' trials
3 - Performed similar on cool task
4 - Low delayers performed more poorly on hot task
Exp 2
Quasi/natural experiment
IV
whether the pp's was a high delayer or low delayer
DV
Performance on impulse control task and imaging results using fMRI - used to examine neural correlates of delay of gratification. Thought low delayers would show diminished activity (less oxygen cons.) in prefrontal cortex and increased activity in ventral striatum.
Sample
27 (13m,14f) - 15 high delayers (5m,10f) and 11 low delayers (7m,4f). 1 person excluded.
Procedure
Hot task (happy or scared faces) while having scan
500ms and 2-14.5s duration
48 Trials, 35 go, 13 no-go
Findings
No difference in HD and LD in terms of reaction time on go task.
HD and LD similar accuracy on go task
Low delayers made more errors than high delayers on the no-go (not significant)
Imaging
- Right inferior frontal gyrus - resisting response, Low delayers had reduced activity with no-go
Ventral striatum - low delayer had higher activity on no-go
Conclusions:
LD showed reduced self control when older, hot cues play a significant role in ability to suppress reactions, differences in brain activity
Key Theme: Regions of the Brain