Anorexia Nervosa

Symptoms
1. Amenorrhoea, low blood pressure, dry and cracking skin, constipation, insufficient sleep, depression and low self-esteem.
Clinical characteristics - DSM-IV-TR
1. A BMI of below 18.5 is an indicator and 15 is clinical.
2. Up to 20% of Clinical AN are fatal.
3. Weight loss that is considered abnormal. Control of weight through unusual eating behaviour.
4. Anxiety about being overweight - excessive fear. Fearful of weight gain.
5. Body image distortion - they do not see their thinness and deny the seriousness of their extremely low body weight. Thinness is vital to self esteem.
Explanations
1. Psychological
  1. Psychodynamic
    1. Hilde Bruch (1973): Origins in early childhood . Effective parents (responding to child’s needs when hungry) vs ineffective parents (who fail to respond to child’s needs). During adolescence they try to exert control and autonomy (more prevalent at this time) but they may be unable to do so as they do not own their own bodies. To overcome this they can take excessive control over the body shape and size by developing abnormal eating habits.
      1. Evaluation
        Origins in early childhood • Effective parents (responding to child’s needs when hungry) vs ineffective parents (who fail to respond to child’s needs) • During adolescence they try to exert control and autonomy (more prevalent at this time) but they may be unable to do so as they do not own their own bodies. • To overcome this they can take excessive control over the body shape and size by developing abnormal eating habits.
    2. Psychodynamic explanations (Freud) – Adolescents don’t want to grow up and separate from their parents. They become fixated at the oral stage when they were completely dependent on their parents. Anorexics lose weight, lose secondary sexual characteristics, become childlike again (asexual) and return to the safety of being a ‘little girl’ again (AO2: Gender Bias) . In Freudian terms, eating and sex are symbolically related. A refusal to eat (the only control, they feel they have) represents a refusal of: stages of psychosexual development; eating as manifest representation of sex (ego-defence).
    3. Evaluation
      1. Supported by observations that parents of adolescents with AN don’t allow their children to define their own needs. (Bruch). Explains why the disorder affects more women and often starts as puberty begins.
  2. Cognitive
    1. The result of faulty maladaptive thought processes about the self, the body, and food/eating, e.g misperceiving the body as overweight when it is actually underweight.
    2. Cognitive errors in EDs
      1. All or nothing thinking ("I ate one biscuit...that has blown everything!")
      2. Overgeneralising ("If I fail at controlling my eating, I fail in life.")
      3. Magnifying/minimising ("My weight loss isn't serious.")
      4. Magical thinking ("If i reach size 8, my life will be perfect.")
      5. Support
        McKenzie et al (1993) – Female ED patients overestimated their own body size in relation to other women – They judged their ideal weight to be lower than comparable nonED patients – Following a sugary snack, they judged their body size to have increased. Controls did not.
    3. Evaluation
      1. AN is certainly associated with biases and distortions in thinking.
        However, most women are dissatisfied with their bodies, not all of them develop EDs.
      2. A good account of what helps to maintain EDs, but not of what causes them in the first place.
  3. Behaviourist
    1. Classical conditioning
      1. A learned association between eating and anxiety
        Eating can be associated with anxiety since it can make people overweight. Losing weight ensures that the individual reduces these feelings of anxiety. -> Feel fat/ugly so diet and associate weight loss with happiness and weight gain with unhappiness.
    2. Operant conditioning
      1. Reinforcement of dieting/weight loss behaviours: compliments from others (positive reinforcement), avoidance of e.g. bullying (negative reinforcement)
        AN is a learned behaviour which is maintained by positive reinforcement (an individual who diets and loses weight is encouraged by society).
        Those that remain overweight get criticised and are disapproved of and sometimes face ridicule because of their bodily appearance.
        Positive reinforcement for weight loss becomes so powerful that the individual maintains the anorexic behaviour despite threats to health which could result in death
    3. Social Learning Theory
      1. Media influences
        Body image concern amongst adolescent girls because of the portrayal of thin models. People imitate and copy people they admire. Young women see female role models rewarded for being slim and attractive. Association of being slim with being successful – vicarious reinforcement. Reward is being received indirectly by observing another person being rewarded. When they slim the reinforcement will be direct.
        Support
        Goresz et al (2001) support the view that the mass media portray a slender beauty ideal. Review of 25 studies showed that this ideal causes body dissatisfaction and contributes to the development of eating disorders. Effect most marked in girls under 19 years. Forehand (2001) found that women feel undue pressure on their appearance and reported that 27% of girls felt that the media pressure them to strive to have the perfect body. Increase in eating disorders in Fiji (Fearn 1999) with the introduction of American television programmes which emphasise a westernised idealised body shape.
      2. People imitate people they admire (Media/Peers etc) – vicarious reinforcement (later reward for gaining the look). They adjust behaviour to achieve the looks of others and gain the rewards.
    4. Evaluation
      1. Face validity in that in the Western society women are exposed to images of thin women and have a complex relationship with food. Helps to explain why so many women diet and why so many women are dissatisfied with their body shape. Problem in that this analysis cannot explain why only a minority of women develop eating disorders. Does not help explain why that so many anorexics continue to starve themselves when they no longer receive praise and compliments about their size – it could be about the attention that they receive that’s reinforcing being anorexic. Underplays the cognitive aspects of anorexia – eg it does not really explain the faulty perceptions of body image that play such a large part in eating disorders.
2. Biological
  1. Neural
    1. Neurotransmitters - serotonin and dopamine . Neurodevelopment - Pregnancy and birth complications. Season of birth
      1. Serotonin
        Disturbances in these levels. Higher serotonin activity in women recovering from binge eating/purging type anorexia. Highest levels of serotonin activity in women who showed the most anxiety. High levels of serotonin are associated with jittery, anxious feelings. In order to get rid of these anxious feelings – the person may stop eating. Suggestion then, that it is the anxiety that triggers Anorexia and that AN is just a symptom of getting rid of the anxiety.
        Evaluation
        Issue in that people with AN when given SSRI’s – makes no difference. Only when used with recovering AN patients does it prevent relapse. Lack of food may stop the SSRI’s from working – but then becomes successful when food is put back into the body.
      2. Dopamine
        PET scans: Comparison of dopamine activity in brains of 10 women recovering from AN and 12 healthy women. Overactivity in dopamine receptors in the basal ganglia. This area dopamine plays a part in interpretation of harm and pleasure. Increased activity alters the way in which people interpret rewards. People with AN find it difficult to associate good feelings with what we normally derive pleasure in – e.g. food.
        Evaluation
        Support from adolescent girls who had higher levels of homovanillic acid (waste product of dopamine). Improvement in weight levels associated with homovanillic levels normalising. Obese individuals – had lower than normal levels of dopamine receptors which means that dopamine levels are perhaps related somehow to body weight.
      3. Neurodevelopment - Pregnancy and birth complications
        Association between premature birth and AN. Brain damage through birth complications causing hypoxia, impairing neurodevelopment of the baby. If mother has eating disorder then baby not getting the nutrition needed. Double disadvantage – as mothers transmit a genetic vulnerability to AN plus inadequate nutrition.
        Evaluation
        Obstetric complications
        Support from Favaro et al (2006): perinatal complications significantly associated with risk of developing AN – placental infarction (obstructed blood supply in the placenta) and early eating difficulties and low birth weight.
      4. Season of birth
        Individuals with Anorexia more likely to be born in spring time. People will get infections in the 2nd trimester – time of year for getting them. Infections such as intrauterine infection and high temperature.
        Evaluation
        Support by Willoughby et al (2005) - they found no seasonality effect in the development of AN where it is hot all year round.
        Support by Eagles et al 2005 – AN individuals are later in birth order compared with healthy controls. The more elder siblings the child has whilst in the womb the more likely the mother will be exposed to common infections. Critical period for brain development is 2nd trimester.
  2. Evolutionary
    1. The reproductive suppression hypothesis. The adapted to flee hypothesis (AFFH)
      1. The reproductive suppression hypothesis (Surbey, 1987)
        Evolution delays the onset of sexual maturation in response to cues in the environment about the probability of poor reproductive success. It enables the female to avoid giving birth at a time when conditions are not conducive to the survival of her offspring. Anorexia Nervosa is a ‘disordered variant’ of the adaptive ability – when may feel unable to cope with biological, emotional and social responsibility of womanhood.
        Basic assumptions
        Weight loss was a strategy for suppressing reproductive capability when food was in limited supply. Pregnancy would have been risky for the mother and survival chances for the infant would have been reduced in the absence of contraceptives. Weight loss would prevent pregnancy at times when it would be too risky
        Based on 2 models
        The reproduction suppression model
        Because reproduction is costly to females, a female facing conditions temporarily unfavourable to reproduction can increase her lifetime reproductive success by delaying reproduction until conditions improve.
        The critical fat hypothesis
        Because a minimum amount of body fat (17%) is needed before menstruation begins and additional fat accumulation (22%) is needed to maintain regular ovulation (Frisch, 1985; Frisch and Barbieri, 2002). Altering the trajectory of adolescent weight gain, or the loss of five pounds or so, could have been an effective mechanism for controlling sexual maturation and fertility in ancestral females.
        Selective pressures favouring reproductive suppression?
        More females than males - more competition from other females = not all females can mate, so those that don’t need to ‘save’ up for lost time
        Attention from ‘undesirable’ males - the youngest females are the most vulnerable because they lack emotional maturity/confidence to rebuff unwanted attention = makes sense to delay reproductive ability until older (when more likely to make the ‘right’ choice of a mate).
        Evaluation
        For: Amenorrhea & the onset of puberty is delayed . Based upon observations of species
        Against: How are the symptoms passed on because this behaviour (AN) will decrease fertility & can kill? General problems with the Evolutionary theory
      2. "Adapted to flee" hypothesis (AFH) - Guisinger, 2003
        Symptoms reflect adaptive mechanisms that caused migration when local famine conditions occurred. Food restriction is a common feature when competition for food, and migration behaviour. Therefore for modern-day individuals, those with a genetic pre-disposition to Anorexia, losing too much weight may trigger ancestral mechanisms. e.g. ‘Holy Anorexia’ in Middle Ages (saints recognised for miraculous ability to live without food)
        Evaluation
        For: Treatment Implications – Guisinger claims AFH ‘relieves therapists of the need to search for familial reasons for Anorexia’. Awareness of this causal influence can help treatment and encourage parents to be more compassionate towards their child.
        This treatment implication is Reductionist as it is ignoring other possible and more complex explanations.
        Against: How have the symptoms been passed on? Anorexia would function effectively in ancestral conditions but can be deadly outside the ecological setting.
    2. General criticisms of evolutionary approach
      1. Reductionist – not search for more complex explanation, such as the emotional relationships within families as a cause. Deterministic – view that an individual’s behaviour is shaped/controlled by internal forces rather than an individual’s will to do something. Cultural Influence – doesn’t acknowledge the importance of cultural influences, e.g. if it is adaptive & innate then why doesn’t it happen in all cultures?
3. Diathesis stress model
  1. Genetic predisposition + environmental trigger

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Anorexia Nervosa

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	Erstellt von Anna Andryeyeva vor fast 9 Jahre