Core studies - Biological Psychology - Casey study

Question 1

What is delayed gratification

Answer 1

Being able to resist temptation and hold off for a greater reward in the end, rather than a smaller reward immediately

Question 2

Aim

Answer 2

To build on previous research to assess whether delay of gratification in childhood predicts impulse control activities when the participants were older

Question 3

Sample

Answer 3

• P’s were taken from the original delay gratification experiments conducted in the 1960s / 1970s
• 59 p’s
• Mixture of high and low delayers
• High delayers: 20W, 12M, mean age 44..6 years
  Low delayers: 16W, 11M, mean age 44.3 years

Question 4

Research Method

Answer 4

-Quasi experiment
-Longitudinal study

Question 5

What was the IV

Answer 5

Whether a p was a high or low delayer

Question 6

What was the DV

Answer 6

-Performance on impulse control task (go/no go task).
-Imaging from and fMRI scanner was also
measured.

Question 7

What materials were used in Experiment 1

Answer 7

• NimStim set of faces with ‘cool’ stimuli ( neutral faces), and ‘hot’ stimuli (happy or fearful faces)

Question 8

What was the procedure in Experiment 1

Answer 8

1. P’s were asked to complete a go/no-go task in their homes
2. P’s completed a COOL and HOT version of this task
3. P’s were instructed to respond as quickly as possible and as accurately as possible
4. A face appeared for 500 milliseconds followed by a one second interval
5. A total of 160 trials were presented per run in a pseudorandomised order

Question 9

Results from Experiment 1

Answer 9

1. There were no significant differences between high and low delayers in terms of reaction times during the trials. There was also no significant difference in terms of accuracy on all of the go trials ( 99.8% COOL, 99.5% HOT)
2. There were significant differences on the no-go trials. The mean false alarm rate for the COOL task was 9.96% and for the HOT trials 12.2%
3. Low delayers performed worse on the HOT task and happy faces acted as the main stimuli to cause false alarms

Question 10

Key finding from Experiment 1

Answer 10

There were significant differences on the no-go trials. The mean false alarm rate for the COOL task was 9.96% and for the HOT trials 12.2%

Question 11

Conclusions for Experiment 1

Answer 11

1. Individuals who had difficulty delaying gratification at age 4 showed more difficulty as adults supressing responses to happy stimuli
2. The results are consistent with the previous work: the context affects how easy it is to delay gratification. The more tempting the cause (e.g ‘hot’ faces) the harder it is to resist

Question 12

Sample in Experiment 2

Answer 12

27 p’s from experiment 1

Question 13

What materials were used in Experiment 2

Answer 13

• Objective E-Prime Software to display the task onto a projection screen
• Neuroscan 5 button response pad
• fMRI scanner which measures brain activity

Question 14

What was the procedure in Experiment 2

Answer 14

1. While in the fMRI scanner, p’s only completed the ‘hot’ version of the go/no-go task
2. The stimuli and instructions were identical to those used in experiment 1 however there were differences in the timing and number of trials
3. There were 2 runs, one with a happy face and one with a fearful face

Question 15

Results from Experiment 2 (Quantitative)

Answer 15

1. The accuracy rates for the hoot task were consistently high for the go trials with an average correct hit of 98.2%
2. The performance was more mixed on the no-go trials with an average 12.4% false alarm rate
3. Low delayer p’s had more false alarms (14.5%) than high delayers (10.9%) however this difference was not statistically significant

Question 16

What is the significance of high activity in the Right Inferior Frontal Gyrus

Answer 16

High activity in this area means that the individual can withhold a response so is a high delayer

Question 17

What is the significance of high activity in the Ventral Striatum

Answer 17

This area of the brain is responsible with rewards. High activity in this area means that a person is most likely a low delayer who cannot delay their gratification

Question 18

Imaging results from Experiment 2 (Right Inferior Frontal Gyrus)

Answer 18

Compared to high delayers, low delayers showed a reduced level of activity in this area when giving correct ‘no-go’ responses

Question 19

Imaging results from Experiment 2 (The Ventral Striatum)

Answer 19

Low delayers have increased activity in this area of the brain compared to high delayers

Question 20

Key Findings

Answer 20

1. Compared to high delayers, low delayers showed a reduced level of activity in this area when giving correct ‘no-go’ responses
   2.Low delayers have increased activity in this area of the brain compared to high delayers

Question 21

Conclusions for Experiment 2

Answer 21

1. The results support the view that the frontal region of the brain is active when resisting temptation on a go/no-go task, and the activation is reduced in low delayers
2. The ventral striatum showed exaggerated activity in low delayers: the more alluring the stimulus, the more low delayers were able to resist
3. Different regions of the brain have more activity for cool and hot systems

Question 22

Overall Conclusions

Answer 22

1. Environmental hot cues plays a significant role in an individual’s ability to supress actions towards alluring cues
2. Resistance to temptation is a relatively stable individual difference that predicts reliable biases in terms of brain activity
3. Individuals who at age 4 have difficulties delaying gratification have difficulty as adults in terms of supressing responses to positive social cues

Question 23

Key overall conclusion

Answer 23

Individuals who at age 4 have difficulties delaying gratification have difficulty as adults in terms of supressing responses to positive social cues

Question 24

Link to Key Theme

Question 25

Link to Area