Depression and OCD Lecture Notes

DEPRESSION

Characteristics of Depression

  • Emotional

    • Persistent low mood

    • Anger

    • Low self-esteem

  • Behavioural

    • Reduced activity levels

    • Sleeping and eating disturbances

    • Aggression or self-harm

  • Cognitive

    • Poor concentration

    • Dwelling on the negative

    • Absolutist thinking (black-and-white thinking)

Explanations for Depression

1. Biological Explanation
  • Genetics

    • Depression runs in families.

    • Concordance rate for identical twins (MZ) is around 40%.

    • This suggests a genetic vulnerability.

  • Neurochemistry

    • Low levels of serotonin are linked to depression.

    • Serotonin affects mood regulation.

Evaluation
  • Strengths:

    • Supported by twin studies.

    • Has practical applications in drug therapy.

  • Limitations:

    • The concordance rate is not 100%, indicating that depression is not purely genetic.

    • Reductionist approach that ignores cognitive and environmental factors.

    • Does not explain why individuals may think negatively.

2. Cognitive Explanation
Beck’s Theory – Aaron Beck
  • Depression is caused by faulty thinking patterns.

  • Beck identified:

    • Negative schemas: These develop from childhood experiences.

    • Faulty information processing: Individuals focus on negatives.

    • The Negative Triad:

    • Negative view of self

    • Negative view of the world

    • Negative view of the future

Ellis’ ABC Model – Albert Ellis
  • A = Activating event

  • B = Belief

  • C = Consequence

  • It is not the event that causes depression, but the irrational belief about the event.

  • Example of irrational beliefs:

    • “I must be perfect.”

    • “If I fail, I am worthless.”

Evaluation of Cognitive Explanation
  • Strengths:

    • Strong research support showing that depressed individuals exhibit a negative bias.

    • Cognitive behavioral therapy (CBT) is effective for treatment.

    • Has real-world applications in therapeutic settings.

  • Limitations:

    • Does not explain all cases of depression, particularly those with biological origins.

    • May lead to blaming the individual for their condition.

    • More effective at explaining reactive depression than endogenous depression.

Treatments for Depression

1. Drug Therapy (SSRIs)
  • Example: Fluoxetine

  • SSRIs (Selective Serotonin Reuptake Inhibitors) block the reabsorption of serotonin in the synapse, which increases serotonin levels in the brain.

Evaluation
  • Strengths:

    • Effective for many individuals suffering from depression.

    • Relatively cheap relative to other forms of therapy.

    • Easy to administer (oral medication).

  • Limitations:

    • Side effects such as nausea and sleep disturbances.

    • High relapse rates upon discontinuation of medication.

    • Does not address underlying cognitive causes of depression.

2. Cognitive Behavioral Therapy (CBT)
  • CBT challenges negative thoughts and replaces them with more rational beliefs.

  • Key components include:

    • Cognitive restructuring: Changing irrational thoughts.

    • Behavioural activation: Increasing engagement in positive activities.

Evaluation
  • Strengths:

    • Addresses the root cognitive causes of depression.

    • Demonstrates long-term effectiveness in alleviating symptoms.

    • Does not produce physical side effects like medications can.

  • Limitations:

    • Often seen as expensive compared to medication.

    • Requires a high level of motivation from the patient.

    • May not be suitable for individuals with severe depression.

OCD (Obsessive Compulsive Disorder)

Characteristics of OCD

  • Emotional

    • Anxiety

    • Distress

  • Behavioural

    • Compulsions (repetitive behaviours conducted in response to obsessions)

    • Avoidance of anxiety-provoking situations

  • Cognitive

    • Obsessions (intrusive, unwanted thoughts)

    • Insight: Awareness that the behaviour is irrational despite feeling compelled to act on it

Explanations for OCD

1. Biological Explanation
  • Genetic Factors

    • Candidate genes have been linked to serotonin levels in OCD.

    • There is evidence that OCD runs in families.

  • Neural Factors

    • Low levels of serotonin are associated with OCD.

    • Overactivity has been noted in the orbitofrontal cortex, a brain area involved in decision-making.

Evaluation
  • Strengths:

    • Offers scientific credibility through genetic and neural evidence.

    • Explains the success of SSRIs as a treatment for OCD.

    • Supported by brain imaging studies that indicate neural involvement in OCD symptoms.

  • Limitations:

    • Not all sufferers respond to drug treatments, highlighting individual differences.

    • Fails to explain the differences in the types or expressions of OCD.

    • A reductionist approach that ignores learning and environmental factors contributing to OCD.

2. Behavioural Explanation – Two-Process Model
  • Proposed by O. Hobart Mowrer

  • OCD is learned through two processes:

    1. Classical Conditioning: A previously neutral stimulus becomes associated with anxiety due to ritualistic behaviours.

    2. Operant Conditioning: Compulsions serve to reduce anxiety (negative reinforcement); therefore, the behaviour is repeated.

Evaluation
  • Strengths:

    • Effectively explains the mechanism behind compulsions.

    • Led to the development of Exposure and Response Prevention (ERP), a successful treatment for OCD.

    • Has practical applications in therapeutic contexts.

  • Limitations:

    • Does not fully explain the presence of obsessions in OCD.

    • Ignores substantial biological evidence.

    • Some compulsions occur without a clear conditioning link, which complicates understanding of the disorder.

Treatments for OCD

1. Drug Therapy (SSRIs)
  • Increases serotonin levels in the brain, alleviating OCD symptoms.

Evaluation
  • Strengths:

    • Effective for many individuals with OCD.

    • Provides a quick treatment option relative to psychotherapeutic approaches.

  • Limitations:

    • Associated side effects that some patients may find intolerable.

    • Symptoms of OCD may return once medication is stopped.

2. Exposure and Response Prevention (ERP)
  • In ERP, the patient is exposed to anxiety triggers while being prevented from performing their compulsions.

  • Over time, this leads to a gradual reduction in anxiety through habituation.

Evaluation
  • Strengths:

    • Demonstrated high effectiveness in reducing symptoms of OCD.

    • Results in long-term improvement of symptoms.

  • Limitations:

    • Can be distressing for the patient during the exposure phase.

    • High dropout rates have been noted among individuals undergoing this treatment.