Casey

• Background

  • Mischel tested on 4 year old children, by putting a marshmallow in front of them and then leaving, saying that they could either eat the marshmallow immediately or getting another one when the researcher returned
• Aims

  • Experiment 1 - to see if low delayers on the marshmallow test at age 4 still struggle with resisting temptation in adulthood
  • Experiment 2 - to examine activity in areas of the brain thought to be associated with the ability to resist temptation
• Sample exp 1

  • Sample was taken from original Marshmallow test
  • Casey was able to get a hold of 27 low delayers and 32 high delayers
  • 59 people aged 44
• Experiment 1 procedure - cool task

  • Participants were shown a series of faces and had to press the 'go' button when they saw a female face and do nothing when there's a male face (which is the no-go task)
  • All faces has neutral expressions
• Experiment 1 procedure - hot task

  • In the hot task, participants were shown 10 faces, this time with either happy or fearful faces
  • The 'go' task was the fearful face and the smiling face was the 'no-go' task
• Brain regions

  • Cool systems are parts of the brain that are involved with cognitive control; these parts of the brain focus on resisting temptation. This includes: the prefrontal cortex, specifically the inferior frontal gyrus
  • Hot systems are parts of the brain that lack control and are more emotional. They are more active when the brain wants a tempting stimuli. This includes the limbic system, specifically the ventral striatum
• Conclusions exp 1

  • The 'high-delayers' (who had been able to delay gratification in the marshmallow test) were found to be much better at resisting pressing the 'go' button when they saw the happy face than 'low-delayers'
• Sample exp 2

  • Of 59 participants from exp 1, 27 took part in the second study
  • 11 low-delayers
  • 15 high-delayers
• Procedure of exp 2

  • Involved participants having fMRI scans whilst taking part in 'hot' tasks
  • 2 tasks, 48 times (35 go, 13 no-go)
  • interval between 2-14.5 second delay
• Conclusions

  • Casey found the 'low-delayers' saw the happy faces and had less activity than the 'high-delayers' in their inferior frontal gyrus
  • Low-delayers had more activity in the ventral striatum (part of the brain associated with rewards)