Two Key Studies of Cognitive Explanations of Major Depressive Disorder (MDD) (SL IB Psychology)

Aaron Beck: highly influential in researching depressive disorders.

Key study one (Beck’s Cognitive Triad): Beck et al. (1974)

Aim: To investigate the role of cognitive distortions in patients with MDD.

Participants: 

• 50 patients with MDD (34 female; 16 male; aged 18-48 years, median=34 years)
• The social demographic of the sample was designated as ‘middle to upper class’
• A control group of 31 non-depressed patients who were undergoing psychotherapy
• The control group had been matched to the MDD group on the variables of age, gender and social demographics

Procedure:

• Clinical interviews were conducted with both groups
• The participants were asked to report on their feelings before the session and to spontaneously contribute their thoughts and feelings throughout the session
• Some of the patients logged their thoughts in diaries or journals which they brought to the sessions
• The therapists kept note of what both groups of patients said during the sessions which then formed the basis of their comparison of the two groups

Results:

• There were distinct differences between the verbalisations and conversational content of the MDD patients compared to the control group patients
• The content of the MDD patients’ verbalisations included a high number of references to the following themes:
• High anticipation of physical harm and danger
• Fear of becoming ill
• High anticipation of being rejected or attacked by others
• A self-blaming bias e.g. feeling that others were more attractive, successful and content than they were and that these ‘failures’ were due to their own ineptitude and inferiority
• A negative self-schema in their beliefs that they were unlovable, that no-one would want to be with them

• These cognitive distortions appeared to be beyond the control of the MDD patients, being automatic and persistent
• The MDD patients expressed belief in their cognitive distortions, they found the distortions plausible and inevitable

Conclusion:

• Patients with MDD suffer from cognitive distortions which cloud their thinking and impede logic and rationality
• The cognitive distortions experienced by the MDD patients appeared to only relate to MDD and not to other disorders such as anxiety

Evaluation of Beck et al. (1974)

Strengths

• The use of the clinical interview generated rich, thick, insightful qualitative data which has strong explanatory power
• The findings have good application i.e. they can be used in therapeutic settings to specifically target the key mechanisms by which MDD affects patients

Weaknesses

• A sample size of 50 MDD patients is small which means that the findings from this study are unlikely to represent the experience of a larger population of MDD patients hence they lack generalisability
• The concept of cognitive distortions may be overly subjective as each person’s thought processes and patterns are likely to differ from another person’s which mean that the research may lack reliability

A patient suffering from cognitive distortions may not ‘see’ themselves as they really are.

Key study one (Early Maladaptive Schemas): Riso et al. (2006)

Aim: 

• To investigate the extent to which Early Maladaptive Schemas (EMS) are stable over time
• To investigate the role of EMS in the experience of MDD

Participants: 55 patients (43 female; 12 male, mean age=40 years; 90% Caucasian) who had been diagnosed with MDD

Procedure: 

• Participants were given a questionnaire designed specifically to measure the extent of their EMS (a total of 16 EMS were identified on the questionnaire)
• The EMS which featured on the questionnaire included:
  • Emotional deprivation - ‘For the most part, people have not been there to meet my emotional needs’
  • Failure to achieve - ‘Most other people are more capable than I am in areas of work and achievement’
  • Vulnerability to harm - ‘I can’t seem to escape the feeling that something bad is about to happen’
  • Subjugation - ‘I feel that I have no choice but to give in to other peoples’ wishes, or else they will retaliate or reject me in some way’
• The severity of depression at baseline was measured and there was a follow-up questionnaire 2.5 to 5 years later

Results: Correlations between EMS at the baseline measurement and the 2.5-5 year  follow-up were high, with a median of 0.75 which shows that MDD had not improved for participants who registered high on the EMS scale.

Conclusion: 

• EMS appear to be stable (i.e. they are consistent in nature and resistant to change or improvement) and long-lasting
• EMS play a key role in MDD into adulthood

Evaluation of Riso et al. (2006)

Strengths: 

• These findings may help to inform treatment for patients with MDD i.e. by identifying EMS at an early stage affords the opportunity to apply remedial interventions such as CBT
• Using baseline and then follow-up measurements helps to increase the validity of the findings as the two measurements can be compared to identify EMS across time

Weaknesses: 

• The participants in this study were MDD patients so the stability of EMS in other mental disorders may be different
• There are potential ethical issues to consider when conducting research with MDD patients: great care must be taken to protect the participants from harm so as not to contribute to the severity of their MDD