Puzziferri Nancy, Zigman Jeffrey M, Thomas Binu P, Mihalakos Perry, Gallagher Ryan, Lutter Michael, Carmody Thomas, Lu Hanzhang, Tamminga Carol A
Department of Surgery, University of Texas Southwestern Medical Center, Dallas, Texas, USA.
Department of Surgery, Veterans Administration North Texas Health Care System, Dallas, Texas, USA.
Obesity (Silver Spring). 2016 Apr;24(4):829-36. doi: 10.1002/oby.21424. Epub 2016 Feb 19.
This study investigated functional brain response differences to food in women with BMI either <25 kg/m(2) (lean) or >35 kg/m(2) (severe obesity).
Thirty women, 18-65 years old, from academic medical centers participated. Baseline brain perfusion was measured with arterial spin labeling. Brain activity was measured via blood-oxygen-level-dependent functional magnetic resonance imaging in response to food cues, and appeal to cues was rated. Subjective hunger/fullness was reported pre- and post-imaging. After a standard meal, measures were repeated.
When fasting, brain perfusion did not differ significantly between groups; and both groups showed significantly increased activity in the neo- and limbic cortices and midbrain compared with baseline (P < 0.05, family-wise-error whole-brain corrected). Once fed, the lean group showed significantly decreased activation in these areas, especially the limbic cortex, whereas the group with severe obesity showed no such decreases (P < 0.05, family-wise-error whole-brain corrected). After eating, appeal ratings of food decreased only in lean women. Within groups, hunger decreased (P < 0.001) and fullness increased (P < 0.001) fasted to fed.
While fasting, brain response to food cues in women did not differ significantly despite BMI. After eating, brain activity quickly diminished in lean women but remained elevated in women with severe obesity. These brain activation findings confirm previous studies.
本研究调查了体重指数（BMI）<25 kg/m²（瘦）或>35 kg/m²（重度肥胖）的女性对食物的大脑功能反应差异。
来自学术医疗中心的30名18 - 65岁女性参与了研究。采用动脉自旋标记法测量基线脑灌注。通过血氧水平依赖性功能磁共振成像测量对食物线索的脑活动，并对线索吸引力进行评分。在成像前后报告主观饥饿/饱腹感。在标准餐后，重复进行测量。
禁食时，两组之间的脑灌注无显著差异；与基线相比，两组在新皮质、边缘皮质和中脑的活动均显著增加（P < 0.05，全脑家族性错误校正）。进食后，瘦组在这些区域的激活显著降低，尤其是边缘皮质，而重度肥胖组则没有这种降低（P < 0.05，全脑家族性错误校正）。进食后，只有瘦女性的食物吸引力评分降低。在组内，饥饿感降低（P < 0.001），饱腹感从禁食到进食后增加（P < 0.001）。
禁食时，尽管BMI不同，但女性对食物线索的大脑反应无显著差异。进食后，瘦女性的脑活动迅速减弱，但重度肥胖女性的脑活动仍保持升高。这些脑激活结果证实了先前的研究。
