Casey et al (2011) - delay of gratification

What was the aim of this study?

To asses whether delay of gratification in childhood predicts impulse and self-control abilities at the behavioral and neural level in adulthood

What was the experiment type?

Quasi experiment (IV is naturally occurring)

What was the IV?

Whether the people were high or low delayers

What was the DV of experiment 1?

Participants performance on a go/no-go task in terms of reaction times and accuracy

Who were the participants?

59 adults (both genders) gathered from previous sample as children - 160 trials in total

What did the experiment involve (what were the tasks)?

If the face presented was male, participants had to press the button, however if it was female, participants withold a button press (go/no-go)

“cool” version of task - male and female faces presented with neural expressions

“hot” version of task - fearful and happy facial expressions

These were the same for experiment 1 and 2, only 2 included an fMRI scanner

What was the DV for experiment 2?

The brain activity while completing the tasks (fMRI)

Who were the participants in experiment 2?

27 adults gathered from the sample of children who agreed to being brain scanned

What were the results?

• no effects on reaction time

• both groups were highly accurate (hot=99.5% cold=99.8% correct)

• low delayers identified at 4 years old showed greater difficulty suppressing their responses on the “hot” task,but not the “cool” task

• the ventral striatum showed higher activity in low delayers, but the right inferior frontal gyrus had less activity in low delayers (they can't resist temptation)

What are some conclusions?

Resistance to temptation is a relatively stable characteristic of an individual over time