Hi all, Gina here, again. This article is short and sweet, as is my post. I’m becoming increasingly interested in some of the more cognitive aspects of eating disorders and seeing as my background on the subject is pretty limited (re: none, although I’m taking a cognitive science class this term), I was hoping to generate some discussion /or references from readers that I could incorporate into further posts. Cheers!
It has long been suggested that people with eating disorders (in this case, specifically anorexia nervosa) display some core deficits in cognitive ability — namely impairments in executive function (Fassino et al., 2002; Pendleton Jones et al., 1991; Tchanturia et al., 2001, 2002, 2004).
If you’re like me and don’t study cognitive science, executive function basically means that people with AN show abnormal mental rigidity, working memory, capacity to manage impulsive responses (response disinhibition) and abstraction skills (i.e. abstract thinking, complex problem solving).
Although the existence of these effects has been studied, at the time of this publication, little had been shown to explain the observed abnormalities. A 2007 study by Tokley and Kemps (available here) explored whether or not a preoccupation with detail could account for impaired executive function in patients with AN.
Specifically, Tokley and Kemps examined the role of field dependence-independence and obsessionality, as indicators of a preoccupation with detail, determining whether these variables could account for poor abstraction in patients with AN. They further studied the roles of perfectionism and mental rigidity (sub-components of obsessionality), as well as anxiety, depression and BMI, in cognitive deficits.
Field dependence-independence refers to a concept in cognitive science in which field independent people tend to focus on parts of things while field dependent people tend to take a more global view of the whole picture. Anorexics have tended to be more field independent, although there is not a universally accepted relationship between the two (Tchanturia et al., 2004).
Tokley and Kemps sampled 24 women age 16-31 with a current diagnosis of AN (being treated at the Flinders Medical Centre Weight Disorder Unit) and 24 healthy controls who were matched to the AN patients based on age, education and socio-economic status. It is worth noting that control patients were eligible for the study if they hadn’t displayed any ED behaviors (as determined by diagnostic questions on the Eating Disorder Examination Questionnaire) for just 4 weeks. In my experience (and I imagine I’m not alone), being behavior free for a month does not necessarily mean that the person doesn’t have an eating disorder (although a month behavior free is great). The authors cite the lack of efficient screening of controls as a limitation of the study, as well.
Mental rigidity, field dependence, obsessionality, abstract thinking, perfectionism and depression/anxiety were all tested by self-reported questionnaires and cognitive assessments. The experimenters also assessed participants verbal IQ, processing speed crystallized intelligence (i.e. specific, acquired knowledge. Which differs from what is known as “fluid intelligence”, or ability to learn/reason) to ensure that results were not due to a general intellectual deficit. The paper goes on to explain exactly what tasks comprised each assessment which seemed a little verbose when I tried to summarize it. Refer to the text for the specific cognitive science behind testing each measure.
Results first indicated that patients with AN have reduced abstract thinking skills.
The table below shows statistical measurements made from assessing preoccupation with detail (click to enlarge).
AN patients displayed a more field-independent cognitive style than the controls…AN patients also reported significantly higher levels of obsessionality and its sub-component perfectionism. However, there was no group difference in mental rigidity…contrary to expectations, AN patients did not display greater mental rigidity [than healthy controls]
I boxed (in red) statistically significant differences between the healthy controls group and patients with AN, however I’d like to point out that since each trait was measured using different assessments, the actual numbers of each measurement in this table (from Tokley and Kemps, 2007) should be taken with a grain of salt. The statistical significance is more important to this particular study than the scores of participants on each assessment.
After establishing that anorexics have a reduced abstract thinking ability compared to the control and that there are significant differences in preoccupation with detail between the two groups, Tokley and Kemps analyzed the data to determine whether or not preoccupation with detail could account for the difference seen in abstraction. Of the various indicators of preoccupation with detail measured in this study, only field dependence–independence made a significant contribution to poor abstract thinking skills. Even low BMI, anxiety and depression showed little correlation to poor abstract thinking. This is concordant with previous findings that have failed to find a relationship between anxiety/depression or weight and cognitive function.
Regardless of the fact that there was not overwhelming support for the hypothesis that preoccupation with detail leads to poor cognitive function, there is evidence that patients with AN are more detail oriented than healthy controls and that they have reduced abstract thinking capacity. Both of these things, separately, can impact treatment of AN.
…a reduced ability to generate plausible solutions to problems and engage in conceptual thought [i.e abstract thinking] may impinge on the ability of AN patients to appreciate the seriousness of their disorder and fully engage in therapy. Hence, strategies aimed at the remediation of poor abstraction and obsessive preoccupation with detail could usefully be incorporated in eating disorders treatment protocols (Lena et al., 2004).
I know in my experience, being too focused on the details has turned things that are supposed to be helpful into a giant mess. For instance: the meal plan. I firmly believe in having a meal plan and I rely on that structure. But I am learning that I have to let go of some of the details and look at the big picture. I have spent numerous dietary sessions arguing about what the measurement of some exchange is, it’s almost more disordered! The meal plan is a good guide, but at this point in my recovery, I need to let go of some of the nitty gritty. This is where abstract thinking would come in handy — if I could conceptualize more than one dimension of the meal plan (i.e beyond “right or wrong”), I could wrap my head around letting go of some of the details.
This is just one example, but my point (and the end line of this paper) is that whether or not there is a cause/effect relationship, cognitive deficits and obsession with detail both play a role in AN and in recovery.
Tokley, M., & Kemps, E. (2007). Preoccupation with detail contributes to poor abstraction in women with anorexia nervosa. Journal of Clinical and Experimental Neuropsychology, 29 (7), 734-41 PMID: 17896199