psych options and paper 3

etiology

cause of development of a disorder

How many people are affected by MDD?

350 million worldwide - WHO

DSM5

Used to diagnose, diagnostic and statistical manual 5

Serotonin hypothesis

Depression and depressive symptoms are caused by insufficient levels of serotonin in the brain

Biological etiologies for mdd

• genes

• serotonin and cortisol hypothesis

Sociocultural etiologies for mdd + studies

• environment - Brown and Harris

• Culture - Parker et al

Brown and harris participant group

458 south london women

Brown and harris procedure

• semi structured interviews about daily lives

• focused on important biographical details e.g. life events

• events were rated in severity by independent researchers

Brown and harris results

• 37 women became clinically depressed in the previous year

• 33 had experienced adverse life events or serious difficulty

• 30% of those who didn’t become depressed faced such adversity

• 4 who became depressed experienced no adversity

Brown and harris conclusion

• 3 major factors affect the development of mdd

• protective factors e.g. intimacy

• vulnerability factors e.g. no confiding relationships

• provoking agents - result in grief and hopelessness

strengths of brown and harris

• high credibility, semi structured interviews gain in depth understanding

• large sample size, reliable results

limitations of brown and harris

• generalisable to only women

• self reporting, impossible to determine the extent of depression for each

• no IV manipulated, no cause and effect

brown and harris aim

• determine the role of environmental factors in the onset of depression in women

parker et al aim

• compare the extent to which depressed chinese in malaysia and caucasians in aus identified both cognitive aspects of mdd and a range of somatic symptoms as a sign of mdd and the reason they sought help

parker et al participants

• 50 malaysians with chinese heritage

• 50 white australians

• all diagnosed with mdd

parker et al procedure

• questionnaire

• 2 sets of symptoms, mood and cognitive common in western diagnostic tools for depression and a set of somatic symptoms observed by singapore psychologists

• questionnaire translated into malay and mandarin, back checked for cred

• patients asked to judge extent to which they experienced each of the 39 symptoms in the last week

• only 4 options - all, most, some, none

parker et al results

• 60% chinese somatic, 13% aus

• aus top 3, anxiety, depressed mood, worry

• malay top 3, health problems, insomnia, concentration

parker et al strengths

• credibility, check with psychiatrists that data is credible

• questionnaire based on cultural evidence

parker et al limitations

• participants chosen based on DSM5 criteria - westernised criteria

• memory distortion and demand characteristics

• does not explain the development, only the manifestation

• malaysia is relatively westernised, globalisation effects

biological etiologies and studies

• genetic predisposition - kendler

• serotonin hypothesis - caspi

Kendler aim

compare the genetic effects on MDD first in mono and dizygotic twins

kendler participants

42161 twins from swedish twin registery

kendler procedure

• only twins whose zygosity could be verified

• telephone interviews assessed lifetime major depression using modified dsm5 criteria

• asked about the twins’ shared environment and individual specific environment

kendler results

• concordance rates for mdd higher in women than men

• higher in monozygotic than dizygotic

• more genetic in origin for women than men

caspi aim

examine the role of the 5htt gene in depression

caspi participants

• 847 NZ 26yo

• assessed for mental health every 2 years until they were 21

caspi procedure

• prospective, longitudinal

• 3 groups based on allele size

• fill in stressful life events questionnaire, frequency of 14 events between 21 and 26

• assessed for depression

caspi results

• one or more short more symptoms of depression and suicidal ideation

• strongest for those with 3 or more stressful life events

• interaction between gene and event

• 2 long had lower rates despite stressful life events

caspi strengths

• supports diathesis stress model - interaction between biology and life experience

• large sample size, reliable

• 5htt regulates serotonin levels, serotonin hypothesis

caspi limitations

• correlational

• other factors still to be explored

cognitive etiologies and studies

• rumination - nolen

• irrational thinking patterns - alloy

nolen aim

carry out a prospective study of the role of rumination on depression symptoms

nolen participant group and procedure

• 1132 adults in san francisco, random dial phone

• interviewed 2x over one year in their own home

• 90 min clinical interview which included a series of tests such as the beck depression inventory (21 item self report rating inventory measures characteristic attitudes and symptoms) and hamilton rating scale (severity of symptoms and track treatment response)

nolen results

• those who showed signs of mdd at the time of the first interview - higher score on ruminative responses

• those who had never been depressed showed lower rumination scores

nolen evaluation

• large sample size but from the same area

• those who have a phone or work

• large variety of data

• low validity, bidirectional ambiguity - symptom or contributor

• ethical

• further research for cause and effect

alloy aim

study the role that one cognitive style plays in the development of depression

alloy participants and procedure

• non depressed college freshmen with no other disorders

• given a test to measure cognitive style

• high risk or low risk for developing depression

• follow up assessments every 6 weeks for 2.5yrs and then every 4 months for 3 yrs

• questionnaires and structured interviews to identify stressful life events, cognitive style and symptoms

alloy results

• In the group with no history of depression:

  • 17% of high risk students developed MDD

  • 1% of low risk developed MDD

  • 29% of high risk showed symptoms of minor depression

  • 6% of low risk showed symptoms of minor depression

  Group with history of depression:

  • 27% of high risk relapsed

  • 6% of low risk relapsed

  • 50% of high risk had symptoms associated with MDD

  • 26.5% of low risk had symptoms associated with MDD

  Rate of suicidality was higher in HR groups 28% than LR groups 12.6%

alloy conclusion

The results are important because it shows how negative cognitive thinking styles can influence depression, and that thinking styles are possibly important to predicting depression

alloy evaluation

• trend in thinking styles and development of mdd

• used triangulation

• WEIRD bias

• sample bias

• self report

• undue stress or harm

prosocial behaviour

behaviour that benefits another or has positive social consequences

kin selection theory

the degree of altruism depends on the genetic similarity of individuals in a group

promoting prosocial behaviour studies

feschback

osswald

feschback aim

investigate whether empathy training in schools can reduce aggressive behaviour in children

feschback participants, procedure, results

• school children - primary

• experimental groups received empathy training, encouraged them to image how others feel, role playing etc

• control group followed regular curriculum

• those who received training showed less aggression, greater emotional understanding

feschback conclusion and evaluation

• effective way to reduce aggression in children

• supports development of school based intervention programs

• supports sct

• non invasive

• limited generalisability

• no long term effect investigated

• subjective

Osswald aim 

video games with prosocial content may foster prosocial behaviour

osswald participant group and procedure

• 36 students, mostly men from german uni

• randomly assigned to one of two conditions

• 2 female researchers gave instructions on how to play, one left, aggrsesive ex entered and was abusive

• willingness to help measured by intervention within 2 mins

osswald results and conclusion

• 4 of 18 who played neutral helped

• 10 of 18 who played prosocial helped

• prosocial games has short term effect on likelihood to intervene

sociocultural prosocial and studies studies

social identity theoruy - drury

social norms - levine

drury aim and participants

• test the role of SIT in helping behaviour

• 40 uni students 20-25, mostly women

• independent samples

drury procedure

• primed by reading news reports about a fire at kings cross, 31 died

• imagine sensations

• leaving england football match or shop in central london

• fire started on platform

• help or push

• small and large crowd

drury results and conclusion

• football helped more, crowd size did not effect

• having in-group identification causes one to be more likely to help and show higher levels of prosocial behaviour

drury evaluation

The study has high internal validity, as it could control for extraneous variables

The study had high mundane realism. Although it was “virtual”, it was still highly realistic

It has low ecological validity because at no time did the participants actually feel that their lives were in danger

The study is replicable, allowing us to test the reliability of the results. The study also appears to confirm the findings of Levine’s research.

The study avoids causing undue stress or deceiving the participants; the study is highly ethical

There is a significant difference between male participants and female participants (7 and 33) which may affect the generalisability of the findings to gender

Relatively small sample size (only 20 participants per condition)

Undue stress caused be reading a news paper about a tragedy occurring

Lower ecological validity in VR as people may not act the same

Levine aim and participants

• how culture and economic situation influneces helping behaviour

• 36 cities across US and 23 worldwide

levine procefure and results

Used observation to observe simple acts of assistance that we encounter every day.

Does a passing pedestrian retrieve a dropped pen?

Does a man with an injured leg receive assistance picking up a fallen magazine?

Will a blind person be helped across a busy intersection?

Will a person try to provide someone with change when asked?

Do people take the time to mail a stamped, addressed letter that has apparently been lost?

America:

• People in small and medium sized cities in the south east were the most helpful

• Residents of large north eastern and west coast cities were the least likely to help

• The best predictor of helping behaviour was population density

International:

• Helping rates tended to be higher in countries with low economic development

• Helping rates were higher in cities with a  slow pace of life, measured by walking speeds, and in cultures emphasising social harmony

• People in communities where social obligations take priority over individual achievements tend to be less economically productive, but show more willingness to assist others

• However, this did not hold for all cities, e.g. pedestrians in the fast-paced, first-world cities of copenhagen and vienna were very kind to strangers

• In contrast, their counterparts in slower-paced Kuala Lumpur were not helpful at all. 

• Indicates that helping tuned to be less dependent on the nature of the local people than on the characteristics of the local environment.

cognitive prosocial and studies

altruism model - toi and batson

empathy model - piliavan

biological prosocial and studies

kin selection - jones

evolution - wedekind

bystanderism and studies

diffusion of responsibility - darley

pluralistic ignorance - piliavin

quota sampling

• decided prior to the start of research how many should be included and characteristics they should have

• driven by research question

snowball sampling

• participants recruit each other

purposive sampling

• defined in advance

• proportions not defined

theoretical sampling

• data saturation reached