Quantifying Exposure to Illicit Drugs & Psychosocial Stress in Real Time

对吸毒和社会心理压力的评估是复杂的，因为它们往往都是短暂的，很难准确回忆。由于因果联系的复杂性和构成环境的难以捉摸的性质，对它们彼此之间的因果联系以及它们的遗传和环境决定因素的评估是复杂的。 在这个项目中，我们通过生态瞬间评估(EMA)近乎实时地评估药物使用和心理社会压力，在EMA中，参与者使用手持电子日记记录事件发生时，并根据全天随机定时的提示报告最近或正在发生的事件。我们还通过让参与者携带全球定位系统(GPS)记录器，以几米的空间分辨率跟踪他们的下落，从而保持对报告事件发生地点的实时记录。我们在一种我们称为地理瞬时评估(GMA)的方法中集体使用这些数据。我们与GMA的目标与了解巴尔的摩发生毒品相关行为的具体地点几乎没有关系，而是要获得关于活动空间(发生日常活动的空间)如何与此类行为及其沉淀物相关联的概括性知识。为此，我们根据客观统计数据对邻近环境进行评分，并更具创新性地根据训练有素的观察员的客观评分进行评分。对于许多成瘾研究人员，如行为遗传学家和药理学临床试验者，这些环境措施将构成需要控制的噪音，因此GMA对他们的好处将是帮助分离感兴趣的生物措施。对于专注于社会科学的成瘾研究人员来说，环境措施将是信号而不是噪音，因此GMA的好处将是为环境干预提供理由，并提供一种严格的方法来评估干预的实施和有效性。 为了增加现场方法的客观性，我们增加了对呼吸、心率变异性和皮肤电反应等生理功能的动态监测。我们对这些措施的目标包括开发能够自动检测行为事件(如吸毒或压力发作)的算法，而不需要自我报告。 为了帮助验证我们的现场方法，我们正在收集所有参与者每周三次的尿样，并通过标准化的实验室程序评估他们的特质应激反应。 我们从这套项目中制作了八份出版物，其中两份是去年的出版物。其中一项研究表明，海洛因和可卡因的使用和渴求的日常时间模式与传统的营业时间有关，这表明反映在营业时间的社会习俗影响着吸毒模式，即使在日常工作时间不一定由就业决定的个人中也是如此。另一项研究表明，女性对药物线索和药物使用的反应与男性不同，这与实验室和大脑成像研究结果一致；这一信息可能有助于制定针对性别的治疗策略。 我们已经将重点转向了一项更大的研究，该研究结合了GPS和其他EMA压力测量方法。我们将EMA和GPS的结合称为地理瞬时评估(GMA)，一种我们可以测量和了解情绪、药物使用和环境暴露于心理社会应激源之间的关系的方法。

Assessment of exposure to drug use and psychosocial stress is complicated by the fact that each is often transient and difficult to recall accurately. Assessment of their causal connections with one another, and of their genetic and environmental determinants, is complicated by the complexity of the causal connections and by the elusive nature of what constitutes the environment. In this project, we are assessing drug use and psychosocial stress in near-real time through Ecological Momentary Assessment (EMA), in which participants use handheld electronic diaries to record events as they occur and to report recent or ongoing events in response to randomly timed prompts throughout the day. We are also maintaining real-time records of where the reported events occur by having participants carry Global Positioning System (GPS) loggers to track their whereabouts with a spatial resolution of several meters. We use these data collectively in a method we are calling Geographical Momentary Assessment (GMA). Our goal with GMA has little to do with knowing the specific Baltimore locations where drug-related behaviors occur, and everything to do with gaining generalizable knowledge about how activity spaces (the spaces in which daily activities occur) are associated with such behaviors and their precipitants. To that end, we score neighborhood environments in terms of objective statistical data andmore innovativelyin terms of objective ratings by trained observers. For many addiction researchers, such as behavioral geneticists and pharmacological clinical trialists, these environmental measures will constitute noise to be controlled for, so the benefit of GMA to them will be to help isolate the biological measures of interest. For addiction researchers with a social-science focus, the environmental measures will be signal rather than noise, so the benefit of GMA will be to make a case for environmental interventions and to provide a rigorous way of assessing the interventions implementation and effectiveness. To increase the objectivity of our field methods, we have added ambulatory monitoring of physiological functions such as respiration, heart-rate variability, and galvanic skin response. Our goals for these measures include the development of algorithms that can automatically detect behavioral events (such as episodes of drug use or stress) without requiring self-report. To help validate our field methods, we are collecting thrice-weekly urine specimens from all our participants and assessing their trait stress reactivity through standardized laboratory procedures. We have produced eight publications from this set of projects, two of those publications are from the past year. One of them showed that daily temporal patterns of heroin and cocaine use and craving are related to conventional business hours, suggesting that societal conventions reflected in business hours influence drug-use patterns even in individuals whose daily schedules are not necessarily dictated by employment. The other one showed that women respond differently than men to exposure to drug cues and to drug use, consistent with laboratory and brain-imaging findings; this information may be useful for development of sex-specific treatment strategies. We have turned our focus to a larger study that incorporates GPS along with additional EMA measures of stress. We refer to the combination of EMA and GPS as Geographical Momentary Assessment (GMA), an approach with which we can measure and understand relationships among mood, drug use, and environmental exposure to psychosocial stressors.