Lowe Cassandra J, Hall Peter A, Staines William R
From the School of Public Health and Health Systems (C.L., P.A.H.) and Department of Kinesiology (P.A.H., W.R.S.), University of Waterloo, Waterloo, Ontario, Canada.
Psychosom Med. 2014 Sep;76(7):503-11. doi: 10.1097/PSY.0000000000000090.
Prior research has demonstrated that executive function (EF) strength is positively associated with dietary self-control. As such, the differential operation of the brain centers underlying EFs (i.e., dorsolateral prefrontal cortex [DLPFC]) may explain controlled aspects of dietary self-control. The present study was designed to examine the causal relationship between DLPFC function and two aspects of dietary self-control: visceral cravings and actual consumptive behaviors.
The research was conducted using a within-participant design. A sample of 21 healthy female young adults aged 19 to 26 years (mean [M; standard deviation] = 21.10 [1.86] years) received both active and sham continuous theta burst stimulation (cTBS) to the left DLPFC. Before and after each session, subjective food cravings were assessed using the Food Craving Questionnaire-State. After each stimulation session, participants competed three measures of EF (Stroop, Go/No-Go, and Stop-Signal) and a bogus taste test.
Participants reported larger increases in snack food cravings after active stimulation (M = 9.98% change, standard error [SE] = 0.45) than after sham stimulation (M = -3.46, SE = 0.39, p = .012) on the reinforcement anticipation dimension of Food Craving Questionnaire-State. Likewise, participants consumed significantly more snack foods after active stimulation (M = 70.62 grams, SE = 5.17) than after sham stimulation (M = 61.33, SE = 3.56, p = .006). Finally, performance on the Stroop task was reduced more after active (M = 71.56 milliseconds, SE = 25.18) than after sham stimulation (M = 20.16, SE = 13.32, p = .033); reduction in Stroop performance mediated the effect of active stimulation on increased appetitive food consumption.
These results support the contention that EF strength, as modulated by DLPFC activity, is causally associated with effective dietary self-control.
先前的研究表明，执行功能（EF）的强度与饮食自我控制呈正相关。因此，EFs（即背外侧前额叶皮层[DLPFC]）背后的脑区的不同运作可能解释饮食自我控制的可控方面。本研究旨在探讨DLPFC功能与饮食自我控制的两个方面之间的因果关系：内脏渴望和实际消费行为。
本研究采用被试内设计。21名年龄在19至26岁之间的健康年轻成年女性（平均[M；标准差]=21.10[1.86]岁）接受了对左侧DLPFC的主动和假连续theta爆发刺激（cTBS）。在每次刺激前后，使用食物渴望问卷状态评估主观食物渴望。在每次刺激后，参与者完成了三项EF测试（斯特鲁普测试、停止信号测试和停止信号任务）以及一项假味觉测试。
在食物渴望问卷状态的强化预期维度上，与假刺激后（M=-3.46，标准误[SE]=0.39，p=0.012）相比，参与者在主动刺激后（M=9.98%变化，SE=0.45）报告的零食渴望增加幅度更大。同样，与假刺激后（M=61.33，SE=3.56，p=0.006）相比，参与者在主动刺激后（M=70.62克，SE=5.17）摄入的零食明显更多。最后，与假刺激后（M=20.16，SE=13.32，p=0.033）相比，主动刺激后（M=71.56毫秒，SE=25.18）斯特鲁普任务的表现下降更多；斯特鲁普任务表现的下降介导了主动刺激对食欲性食物消费增加的影响。
这些结果支持了这样一种观点，即由DLPFC活动调节的EF强度与有效的饮食自我控制存在因果关系。
