Davis Caroline, Levitan Robert D, Muglia Pierandrea, Bewell Carmen, Kennedy James L
York University, 343 Bethune College, 4700 Keele Street, Toronto, ON M3J 1P3, Canada.
Obes Res. 2004 Jun;12(6):929-35. doi: 10.1038/oby.2004.113.
To demonstrate that human overeating is not just a passive response to salient environmental triggers and powerful physiological drives; it is also about making choices. The ventromedial prefrontal cortex has been strongly implicated in the neural circuitry necessary for making advantageous decisions when various options for action are available. Decision-making deficits have been found in patients with ventromedial prefrontal cortex lesions and in those with substance dependence--impairments that reflect an inability to advantageously assess future consequences. That is, they choose immediate rewards in the face of future long-term negative consequences.
We extended this research to the study of overeating and overweight, testing a regression model that predicted that poor decision making (as assessed by a validated computerized gambling task) and a tendency to overeat under stress would correlate with higher BMI in a group of healthy adult women (N = 41) representing a broad range of body weights.
We found statistically significant main effects for both independent variables in the predicted direction (p < 0.05; R2 = 0.35). Indeed, the decision-making impairments across the 100 trials of the computer task were greater in those with high BMI than in previous studies with drug addicts.
Findings suggested that cortical and subcortical processes, which regulate one's ability to inhibit short-term rewards when the long-term consequences are deleterious, may also influence eating behaviors in a culture dominated by so many, and such varied, sources of palatable and calorically dense sources of energy.
证明人类暴饮暴食不仅仅是对显著环境诱因和强大生理驱力的被动反应；它还涉及做出选择。腹内侧前额叶皮层在面对多种行动选择时做出有利决策所需的神经回路中起着重要作用。在腹内侧前额叶皮层受损的患者以及物质依赖患者中发现了决策缺陷——这些损伤反映出无法有利地评估未来后果。也就是说，他们在面对未来长期负面后果时选择即时奖励。
我们将这项研究扩展到暴饮暴食和超重的研究，测试了一个回归模型，该模型预测决策能力差（通过一项经过验证的计算机化赌博任务评估）以及在压力下暴饮暴食的倾向与一组体重范围广泛的健康成年女性（N = 41）的较高体重指数相关。
我们发现两个自变量在预测方向上均有统计学显著的主效应（p < 0.05；R2 = 0.35）。事实上，在计算机任务的100次试验中，高体重指数者的决策损伤比之前对吸毒成瘾者的研究中更大。
研究结果表明，当长期后果有害时调节个体抑制短期奖励能力的皮层和皮层下过程，也可能在一个由如此多且多样的美味和高热量能量来源主导的文化中影响饮食行为。
