Data dictionary.xlsx

These data were collected from 4 laboratory visits and from one screening survey prior to participation. Participant consent to provide personal information was obtained prior to the screening survey and informed consent was obtained before participation in study procedures. All study procedures were approved by the Institutional Review Board at the University at Buffalo. This study tested delay discounting, relative reinforcement of snack food and <i>ad libitum</i> energy intake following one engagement of episodic future thinking (EFT), or the control episodic recent thinking (ERT). Visits 1 and 2 occurred prior to one week of daily engagement in EFT or ERT, and visits 3 and 4 occurred following 1 week of daily engagement in EFT or ERT. Anthropometric data and participant characteristics were collected on visit 1 along with a delay discounting task (Rollins, Dearing, Epstein, 2010), and snack food buffet to test <i>ad libitum</i> energy intake. The delay discounting task and snack food buffet were repeated on visit 4. Relative reinforcement value (RRV) of high energy dense (HED) compared to low energy dense (LED) snack food was measured on visit 2 and again on visit 3. The dependent variables, described in more detail in the full manuscript, analyzed from these tasks are listed below:Delay discounting task: area under the curve (AUC) calculated by plotting indifference points at 7 delays. Greater AUC= less discounting<i>Ad libitum</i> buffet: total energy intake, energy from HED food and energy from LED food (all in terms of kilocalories)RRV: breakpoint, or the highest schedule of reinforcement completed for HED and LED food.During the study, participants also completed a self report measure of impulsivity, the Barratt Impulsiveness Scale (BIS) (Patton, 1995). This scale was administered upon screening, during visit 1 and again on visit 4. They also completed a digital adjusting delay task (Koffarnus and Bickel, 2014) every day after engaging in EFT or ERT, and the natural log of k, the discount rate, was analyzed as the primary dependent measure from this task. <br><br>

本数据集采集自4次实验室访视及1次参与前的筛查问卷。在开展筛查问卷前，已获取受试者提供个人信息的知情同意；在参与研究流程前，亦已获取正式的研究知情同意。所有研究流程均已通过布法罗大学（University at Buffalo）机构审查委员会的伦理批准。

本研究旨在测试单次情景未来思维（episodic future thinking, EFT）启动后的延迟折扣效应、零食的相对强化效应，以及自由进食（ad libitum）能量摄入情况，并设置情景近期思维（episodic recent thinking, ERT）作为对照。受试者需先完成为期1周的每日EFT或ERT训练，访视1与访视2安排在训练开始前，访视3与访视4则安排在1周训练结束后。

访视1期间采集了受试者的人体测量学数据与基本特征，同时施测了由Rollins、Dearing与Epstein（2010）开发的延迟折扣任务，并通过零食自助餐范式测试自由进食能量摄入。访视4重复了延迟折扣任务与零食自助餐测试。访视2与访视3分别测量了高能量密度（high energy dense, HED）零食相较于低能量密度（low energy dense, LED）零食的相对强化价值（relative reinforcement value, RRV）。

本研究从上述任务中分析的因变量详见正式手稿，以下为简要列举：
1. 延迟折扣任务：通过绘制7个延迟条件下的无差异点计算曲线下面积（area under the curve, AUC），AUC值越大代表延迟折扣程度越低。
2. 自由进食自助餐测试：总能量摄入、高能量密度食物供能与低能量密度食物供能（单位均为千卡）。
3. 相对强化价值：断点值，即受试者可完成的高、低能量密度食物强化安排的最高等级。

研究期间，受试者还完成了Barratt冲动量表（Barratt Impulsiveness Scale, BIS，Patton, 1995）这一自我报告式冲动性测评工具，分别在筛查时、访视1及访视4进行施测。此外，受试者在每日完成EFT或ERT训练后，均需完成数字调整延迟任务（Koffarnus与Bickel, 2014），本研究以该任务中折扣率k的自然对数作为主要因变量进行分析。