Disorders - Explanations

Question 1

What was the aim of Lewinsohn’s study on explanations of depression?

Answer 1

To compare the amount of positive reinforcement received by depressed and non-depressed patients.

Question 2

What was the sample in Lewinsohn’s study on explanations of disorders?

Answer 2

30 in total - 10 participants who were diagnosed with depression, 10 who had a disorder other than depression (psychiatric controls) and 10 who did not have a disorder at all (control group).

Question 3

What was the procedure of Lewinsohn’s study on explanations of disorders?

Answer 3

Participants asked to check mood daily using the depression adjective checklist and complete the pleasant activities scale, rating 320 activities twice on a scale of three - once for pleasantness and once for frequency. This is how Lewinsohn operationalised positive reinforcement.

Question 4

What are the results from Lewinsohn’s study on explanations of disorders?

Answer 4

Significant positive correlations between mood ratings and pleasant activities. Individual differences from 0 to -0.66, showing there is more to depression than reinforcement from pleasant activities.

Question 5

What did Lewinsohn’s study on explanations of disorders conclude?

Answer 5

There appears to be a link between reinforcement from pleasant activities and mood, but more research is needed to identify the individual characteristics that make some people more influenced by pleasant activities than others.

Question 6

What are three strengths of Lewinsohn’s study on explanations of disorders?

Answer 6

+ High internal reliability – self report measures were standardised.
+ High ecological validity – real patients with real depression/other psychiatric disorders.
+ Increased internal validity/usefulness due to use of control group.

Question 7

What are three weaknesses of Lewinsohn’s study on explanations of disorders?

Answer 7

• Lower internal validity – Self reports mean that social desirability bias and demand characteristics will influence responses.
• Low external reliability – only 30 PPS mean that individual differences will have a larger influence on the results.
• Low internal validity due to lack of control over extraneous variables, despite being reductionist. This reduces usefulness.