A recent editorial published in the American Journal of Clinical Nutrition discusses the use of a new imaging technique to study how certain structural features of the hypothalamus affect eating behavior.

Women are more likely than men to develop eating disorders such as anorexia nervosa, especially during puberty. Despite this, the role of the female brain in neurology and psychiatry has been studied in several studies. The hypothalamus is a small heterogeneous brain structure in the intermediate brain that regulates homeostatic and hedonic functions related to eating behavior. Current imaging techniques are limited in their ability to capture subsegmentation of the nuclei in the hypothalamus. As a result, most studies investigating the role of the hypothalamus have been conducted in rodents.

In a previous study published in the Journal of Clinical Medicine, researchers identified microstructural changes in the hypothalamus of young adult women with anorexia nervosa and obesity. To this end, high-sensitivity, ultrahigh-resolution quantitative T1 magnetic resonance imaging (MRI) is needed to overcome the limitations of conventional imaging techniques that do not allow visualization of the human hypothalamus.

In this study, the hypothalamus of forty-four young women was examined, twenty-one of whom were normal weight, thirteen were diagnosed with restrictive anorexia nervosa, and ten developed obesity. Appropriate age matching eliminated any possible age-related bias.

Volumes and quantitative T1 values of individual hypothalamic nuclei, which served as indirect markers of cellular integrity, were compared after whole-brain normalization using nonparametric tests. 

Multivariate nonlinear partial least squares (NIPALS) analysis was performed to identify factors associated with body mass index (BMI) and eating disorders, such as ghrelin and leptin levels, magnetic resonance imaging (MRI) parameters of hypothalamic nuclei, depression, and anxiety. 

As part of this multidisciplinary strategy, 7T-MRI data from hypothalamic compartments were compared with measures of eating behavior, anxiety, mood, and peripheral levels of hormones related to hunger and satiety.

 Volumetric data and quantitative T1 scores were obtained for 50 different hypothalamic brain regions.

Patients suffering from anorexia nervosa and, to a lesser extent, obesity, were found to have characteristic differences in the para- and periventricular nuclei of the hypothalamus, as well as in connective fibers, compared with normal-weight patients.

Both para- and periventricular nuclei were found to play a crucial role in eating behavior, indicating that any microstructural changes in these areas may contribute to the pathophysiology of eating disorders.