DEPRESSION

Symptoms of DepressionT H E R E A R E F O U R M A I N C AT E G O R I E S T H AT T H E S Y M P T O M S O F D E P R E S S I O N F I T I N T O :

CognitiveBehaviouralEmotionalPhysical

Cognitive Symptoms

Low self esteem Guilt Self dislike Loss of libido Negative thoughts Suicidal thoughts Poor memory Lack of ability to think and concentrate

Behavioural Symptoms

Decrease in sexual activity Loss of appetite Disordered sleep patterns Poor care of self and othersSuicide attempts

Emotional Symptoms

SadnessIrritabilityApathy (no interest in or pleasure in activities)

Physical Symptoms

£ Loss of weight£ Loss of energy£ Aches and pains£ Sleep disturbance£ Menstrual changes

GENETIC STUDIES

Gershon (1990) - TEN FAMILY STUDIES.

Depression assessed in FIRST DEGREE RELATIVES of patients with depression.

UNIPOLAR DEPRESSION was 7-30% higher than in general popluation.

AO2 – share the same environment

HARRINGTON (1993)

Adoption study

Study of adoptees – biological relatives are more likely to have DEPRESSION than adoptive relatives.

20% of biological relatives

5-10% of adoptive relatives

Ao2 - RAISED APART FROM THEIR BIOLOGICAL PARENTS

Biochemical explanations of depression

WHAT ARE THE NEUROTRANSMITTERS INVOLVED IN?

Drugs previously used to treat high blood pressure i.e. reserpine (which reduces the availability of noradrenaline) caused the side effect of depression/suicidal tendencies in some patients.

The success of Tricyclic drugs and more recently SSRI’s such as prozac suggests low

levels of serotonin are responsible for depression (as these drugs work by

increasing levels of serotonin)

Non-human animals given drugs that reduce noradrenaline production become sluggish and inactive (symptoms of depression) AO2 anthropomorphism

Mann (1996) found impaired serotonin transmission in people with depression (using PET scans)

A02

Unsure whether it is low levels of BOTH, low levels of EITHER or an imbalance compared to each other that causes depression.

MORE RESEARCH NEEDED!

AO2 Treatment aetiology fallacy

JUST BECAUSE THE TREATMENT WORKS, DOESN’T MEAN LOW SEROTONIN IS THE CAUSE!

If you take paracetemol to get rid of your headache, it doesn’t mean your body is lacking paracetemol.

Just because SSRI’s increase Serotonin, does not necessarily mean low levels of Serotonin have caused depression. MAY BE OTHER FACTORS.

PSYCHOLOGICAL EXPLANATIONS

GENERAL AO2

GENERAL A02

Stressful life events

Brown and Harris identified a number of vulnerability factors:

Working class

Single mothers

Inner city location

Parental indifference in childhood or physical/ sexual abuse

AO2

Gender bias

Correlational evidence – can’t infer cause and effect

Practical applications – identifying risk factors allows them to be addressed

e.g. Support for single mothers in the welfare system

Interviews (in-depth but possibility of interviewer bias)

LOCK and KEY EXPLANATION

1) Early adverse experience forms LOCKS

2) Activated by KEYS mirroring previous bad experience

3) This causes depression

Examples:

Mother left when you were young THEN husband leaves you.

Loss of parent -> loss of job

AO2

Has been incorporated into the DSM assessing social and environmental circumstances

Logical

Supporting evidence – Parker et al (1998) found this to be the case in a significant proportion of patients in their sample.

In many cases, patients do not report CRITICAL LIFE EVENTS at the onset of their depression.

Many people have ongoing stressors in their lives but do not experience clinical depression.

COULD THE ENVIRONMENT BE A TRIGGER rather than a cause?

Cognitive explanations of depression

Ao2

What did it show?

ECOLOGICAL VALIDITY

ETHICS

ANTHROPOMORPHIC

SELIGMAN

GROUP ONE– Harnessed up and then let go.

GROUP TWO - Dogs subjected to ELECTRIC SHOCK (with no way of controlling this)

Day TWO

Dogs then placed in a SHUTTLE BOX – The boxes were split into two sides, one where dogs were subjected to electric shocks, one where the dogs were safe.

Could avoid shocks by jumping across barrier.

Group one dogs jumped over.

WHAT DO YOU THINK GROUP TWO DOGS DID?

HIROTO, 1974

PPT’s exposed to LOUD, UNPLEASANT NOISE which they couldn’t turn off.

Faced in front of a FINGER SHUTTLE BOX (had a handle of the top)

Moving handle stopped noise.

When NOISE began they PASSIVELY ACCEPTED IT

PPT’s who hadn’t been exposed to noise learned to move the handle

and stop the noise.

Seligman’s hopelessness theory of depression

An attribution is an explanation of why something happens (the cause of behaviour)

Depression results from the explanations people give for their behaviours.

Depressed people attribute behaviour to three causes

1) Internal –coming from within- blame themselves

2) Stable – an enduring trait-things will always be that way

3) Global – affects all aspects of life

Example

“I’m inadequate, I will always be inadequate and I am inadequate at everything”

Evidence for

Metalsky (1987) looked at students who did badly in their psychology exam.

Two days after, those who attributed failure to internal, stable and global causes continued to be mildly depressed.

Students who made different attributionse.g. ‘the exam was really hard’ had recovered.

AO2 – LEARNED HELPLESSNESS

CAUSE or EFFECT? – Does depression cause learned helplessness?

ECOLOGICAL VALIDITY – e.g. Hiroto and Seligman

Evidence against

Cannot generalise Metalsky’s study to major depressive disorder which is more severe.

Cannot explain where attributions come from in the first place – problems with addressing this.

Do attributions precede or follow depression – difficult to establish cause and effect.

Often done in LABS (e.g. Hiroto and Seligman)

When done with humans, samples are often STUDENTS – SAMPLE BIAS.

Much evidence comes from ATTRIBUTIONAL BIAS QUESTIONNAIRE - some researchers believe forces people into a type of thinking that doesn’t reflect that of real life (ANDERSON ET AL, 1994)

Beck’s cognitive theory of depression

Emotions are controlled by cognitive schemas (mental constructions of the world).

People’s experiences are understood in the light of these schemas.

Schemas develop as a result of childhood experience.

Beck’s cognitive theory of depression

Emotions are controlled by cognitive schemas (mental constructions of the world).

People’s experiences are understood in the light of these schemas.

Schemas develop as a result of childhood experience.

Negative thinking

People who become depressed have negative cognitive schemas

This can lead to errors in thinking. Examples include overgeneralisation or selective abstraction.

Example

OVERGENERALISATION – drawing a conclusion from a particular event and applying it generally

SELECTIVE ABSTRACTION – forming conclusions based on isolated detail whilst ignoring contradictory evidence

Cognitive triad

Errors in thinking can produce a negative cognitive triad – negative views of (1) self (2) world and (3) future

“I am worthless, the world is a miserable place, the future is hopeless”

Evidence for

Research indicates that compared to nondepressed people, depressed individuals have more negative

thoughts about themselves, the world and the future.

Evidence against

However, does negative thinking precede the onset of depression or does it result from it.

According to Davison & Neale (1998) ‘ depression can make thinking more negative, and negative thinking can probably cause and worsen depression’.

LONGITUDINAL STUDIES

More of these are needed

BARLOW and DURAND (1999)

Temple Wisconsin study - non-depressed university students

First two years of this study suggests NEGATIVE thinking precedes DEPRESSION.

17% of high risk ppts (high scores on negative thinking) at the

beginning of the study started went on to develop depression as

opposed to 1% of low risk ppt’s (low scores on negative thinking)

Evaluation of cognitive theory

takes account of cognitions and looks at depression from the patients perspective. Important to be patient focused. Cognitions may vary from person to person.

PRACTICAL APPLICATIONS– success of CBT based on Beck’s theory (used extensively on the NHS)

CAUSE and EFFECT issues

ETHICAL ISSUES– blames the individual for their own negative thoughts

REDUCTIONIST

DIATHESIS-STRESS MODEL

Interaction between DIATHESIS (predisposition) and STRESS (from the environment)

Caused by ‘TRIGGERS’.

Stressful events may lead to depression.

WEISSMAN et al, 1991 – depression rates from people who are SEPARATED/DIVORCED is 3 TIMES HIGHER than in married people.

TAKES INTO ACCOUNT different theories (e.g. Lock and key, genetics) but also

accounts for ENVIRONMENTAL FACTORS.