University of Colorado Anschutz Medical Campus, School of Medicine.
J Am Acad Child Adolesc Psychiatry. 2013 Oct;52(10):1066-1075.e5. doi: 10.1016/j.jaac.2013.07.007. Epub 2013 Aug 27.
The neurobiological underpinnings of anorexia nervosa (AN) are poorly understood. In this study, we tested whether brain gray matter (GM) and white matter (WM) in adolescents with AN would show alterations comparable to those in adults.
We used magnetic resonance imaging to study GM and WM volume, and diffusion tensor imaging to assess fractional anisotropy for WM integrity in 19 adolescents with AN and 22 controls.
Individuals with AN showed greater left orbitofrontal, right insular, and bilateral temporal cortex GM, as well as temporal lobe WM volumes compared to controls. WM integrity in adolescents with AN was lower (lower fractional anisotropy) in fornix, posterior frontal, and parietal areas, but higher in anterior frontal, orbitofrontal, and temporal lobes. In individuals with AN, orbitofrontal GM volume correlated negatively with sweet taste pleasantness. An additional comparison of this study cohort with adult individuals with AN and healthy controls supported greater orbitofrontal cortex and insula volumes in AN across age groups.
This study indicates larger orbitofrontal and insular GM volumes, as well as lower fornix WM integrity in adolescents with AN, similar to adults. The pattern of larger anteroventral GM and WM volume as well as WM integrity, but lower WM integrity in posterior frontal and parietal regions may indicate that developmental factors such as GM pruning and WM growth could contribute to brain alterations in AN. The negative correlation between taste pleasantness and orbitofrontal cortex volume in individuals with AN could contribute to food avoidance in this disorder.
目前人们对厌食症（AN）的神经生物学基础知之甚少。本研究旨在测试青少年 AN 患者的大脑灰质（GM）和白质（WM）是否存在与成人相似的改变。
我们使用磁共振成像研究 GM 和 WM 体积，使用弥散张量成像评估 WM 完整性的各向异性分数（fractional anisotropy，FA），对 19 名 AN 青少年和 22 名对照组进行了研究。
与对照组相比，AN 患者左侧眶额回、右侧岛叶和双侧颞叶 GM 以及颞叶 WM 体积更大。与对照组相比，AN 患者的穹窿、额后和顶叶 WM 完整性较低（FA 值较低），而额前、眶额和颞叶 WM 完整性较高。在 AN 患者中，眶额 GM 体积与甜味愉悦感呈负相关。对该研究队列与成人 AN 患者和健康对照组的进一步比较支持了跨年龄组 AN 患者眶额皮质和岛叶体积更大。
本研究表明，青少年 AN 患者的眶额和岛叶 GM 体积较大，穹窿 WM 完整性较低，与成人相似。前腹侧 GM 和 WM 体积较大而额后和顶叶 WM 完整性较低的模式可能表明 GM 修剪和 WM 生长等发育因素可能导致 AN 患者的大脑改变。AN 患者的味觉愉悦感与眶额皮质体积呈负相关，这可能导致该疾病中对食物的回避。
