Explanations for Anorexia Nervosa

Holland et al (twin studies)

34 twin pairs

concordance rate 56% for MZ and 5% in DZ

Van Zeeland (candidate gene)

compared 152 genes in 1205 women with AN and 1948 without AN

variants of EPHX2 gene more common in AN

Kaye et al (dopamine activity)

decreased dopamine levels associated with AN

Bailer et al (dopamine activity)

administered dopamine, control group administered euphoria, AN group experienced anxiety

AN restrict eating to reduce anxiety

Serotonin

high levels of serotonin suppress appetite and increase anxiety and obsessive behaviour

restricting food may be self help, serotonin levels drop as a result of less food, meaning calmness and a sense of control

Evaluation of biological explanation

limitation of twin studies

polygenic basis

diathesis stress model

research support

oversimplistic

drug treatments

Family systems theory - Minuchin

enmeshment

rigidity

overprotectiveness

conflict avoidance

control and autonomy

Enmeshment

family members are over involved with each other

boundaries are fuzzy due to poorly defined roles and lack of leadership

self identities are tied up

adolescent daughter struggles to assert independence and differentiate from everyone else’s especially the mother

refuses to eat to assert independence

Overprotectiveness

family members nurture each other obsessively

family loyalty is reinforced, no room for independence

Rigidity

interactions are inflexible

members deny the need for change and work hard to maintain things as they are

internal pressure or external threat e.g. daughter self starving

family is too rigid to adapt and is thrown into a crisis

Conflict avoidance

priority is to avoid conflict or suppress it if it occurs

no discussion of any issues where a difference of opinion might arise

issues fester until a crisis develops

daughter starves herself and the family refuses to accept there is anything to discuss

Autonomy and Control (Bruch)

adolescent daughter struggles to achieve autonomy and control

mother is intrusive

outcome is confusion in the daughter; distorted body image, inability to identify body states, loss of control

self starvation is an attempt to control self-identity

weight loss is visible measure of success

Evaluation for family systems theory (Minuchin)

Brockmeyer - 112 AN patients and control group, AN desire to be autonomous

Strauss and Ryan - AN had more disturbances of autonomy and more controlling style of regulating behaviour

treatment application

explanatory power

vague and hard to define

methodological issues

ethical issues

correlational

gender biased

SLT explanation for AN - modelling

acquired indirectly through observation of a model

model can exist in real life or can be symbolic

models modify social norms by establishing what is acceptable or usual behaviour

especially influential if a child identifies with the model

SLT - Vicarious reinforcement

if a model is rewarded, such as being praised for losing weight, imitation is more likely

family members are major sources of vicarious reinforcement because observation is repeated frequently

SLT - Role of the media

young women may identify with the glamour of female celebrities who conform to the ‘thin ideal’

this motivates them to behave in ways that help them to lose weight and achieve thinness

vicariously reinforced by rewarding fame, success, wealth, respect, satisfaction

Dittmar et al (SLT)

162 British girls aged 5-8

group 1 - barbies

group 2 - Emme dolls

group 3 - flowers, balloons, etc

rated statements of body esteem and coloured in body silhouettes

barbie group more dissatisfied with body shape and lower body esteem

SLT evaluation

Becker et al - 13% at risk of eating disorder in Fiji, after TVs 29% at risk

cultural differences

no effective therapies

validity - applicable to young women who use social media etc

Cognitive explanation for AN

disturbed perceptions (Murphy et al)

irrational beliefs (Beck)

cognitive inflexibility (Treasure and Schmidt)

Disturbed perceptions - Murphy et al

all clinical feature of AN stem from disturbed perceptions

people with AN become more and more critical of their own bodies

misinterpret emotional states as ‘feeling fat’, even as they get thinner

people with AN constantly overestimate their body size

Williamson et al - ‘body image assessment’ - AN less accurate in size estimates than non AN, ideal size thinner than control

Irrational beliefs

lead to automatic negative thoughts

all or nothing thinking

catastrophising

perfectionism

record keeping

Hewitt - perfectionism is not satisfied when goals are met, but they are just raised

Cognitive inflexibility (Treasure and Schmidt)

Cognitive Interpersonal Maintenance Model of AN - people with AN experience problems with set-shifting

find it difficult to switch from one task to another with different skills

apply same skills to changed situation

once started on weight loss process, rigidly persist with it

weight loss is a solution to a problem that no longer exists, but unable to see this

Evaluation of cognitive explanation

Steinglass et al - 68% had main fear of gaining weight and becoming fat, 20% classed as delusional

Halmi et al - childhood perfectionism associated with current AN symptoms (but, retrospective)

correlational findings

CBT as effective treatment