casey

• What was the aim?


  To build on existing research to assess if delay of gratification in childhood predicts impulse control ability and sensitivity to social cues in adults
• What was the sample?


  562 4-year olds took part in a delay of gratification test

  They all went to Stanford bing nursery

  155 took part in a questionnaire in their 20s

  59 took part in exp 1

  27 took part in exp 2
• What was the method?


  Longitudinal, quasi-experiment

  IV- whether the ppnt was a high or low delayer (naturally occurring)

  DV exp1: Performance on the impulse control test

  DV exp2: Imaging results using fMRI
• What was the procedure? (Experiment 1)


  59 ppnts already assigned as high or low delayers from childhood took part in 2 versions of the go/no go task

  1. The cool version- ppnts were shown either a female or a male face as the stimuli- each gender was assigned as "go" or "no go"

  Ppnts were told to click the button on the "go" stimulus

  2. The hot version was identical but this time the stimulus was fearful or happy faces

  The stimuli were shown for 500ms with a 1-sec interval

  160 trials were done in a pseudorandom order

  The task was a programme on a laptop sent to ppnts homes

  Accuracy and reaction time were recorded
• What was the procedure? (Experiment 2)


  An fMRI scanner was used to detect neural connections with delay of gratification

  Ppnts took part in the hot version of the go/no go task

  Stimuli were shown for 500ms with ranging intervals

  Tasks were viewable through a rear projector and had a five-buttoned response pad which recorded button responses and response time
• What were the results? (Experiment 1)


  The reaction time was similar in both groups

  Low delayers showed more difficulty suppressing emotions

  In the "go/no go" trial:

  -"Go"- ppnts gave similarly accurate responses

  -"No-go"- low delayers made more mistakes

  
  

  In the "cool/hot" trials

  -"Cool"- ppnts gave similarly accurate responses

  -"Hot"- low delayers performed more poorly
• What were the results? (Experiment 2)


  The reaction time and accuracy was the same as experiment 1

  The right inferior frontal gyrus was involved in accurately withholding responses (more active in high delayers)

  The ventral striatum was more active in the happy face no-go trial for low delayers (overall more active in low delayers)
• What were the conclusions?


  The right inferior front gyrus is associated with being able to delay gratification

  The ventral striatum is associated with impulsivity and not being able to delay gratification

  Delay of gratification is stable across the lifetime