Participants

Inclusion criteria for the patient group were: AN as the primary diagnosis at the time of recruitment, Norwegian as the first language, and the patient’s somatic ability to complete the assessment. Exclusion criteria included confirmed brain damage, psychosis, diabetes, chronic fatigue syndrome, neurological disease, and neuropsychiatric disorders. A total of 22 female patients with AN fulfilled the criteria. One patient had to be excluded because she was a demographic outlier with no comparable healthy control, leaving a group of 21 patients with AN. At the time of recruitment, 19 of the patients were inpatients and two were outpatients. All patients were in a weight-restoration phase, and to the best of our knowledge, none of them were in a state of starvation. The patients were in different stages of their treatment, and at the time of recruitment, three patients weighed above the weight criterion for AN, according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision.¹⁸ The included patients were using their regular medication. At the time of recruitment, 16 patients used either nontricyclic antidepressants (n=14) or antipsychotics (n=6).

A control group of 25 participants of the same age and sex and with the same educational characteristics were recruited for comparison. Exclusion criteria were the same for the control group and patients, with the following supplementary criteria: current or prior eating disorder or eating problems, being on a diet for weight reduction, a body mass index <19 kg/m² or >26 kg/m², and/or currently having a psychiatric diagnosis. One control met the exclusion criteria and was therefore excluded. The demographic and clinical characteristics of the sample are presented in Table 1. Written informed consent was acquired from all participants in accordance with the Declaration of Helsinki.

Demographic variables

Note:

Abbreviations: BMI, body mass index; FIQ, full-scale intelligence quotient; GAI, general ability index; POI, perceptual organization index; PSI, processing speed index; VCI, verbal comprehension index; WMI, working memory index; SD, standard deviation.