Addiction, Mental Health Research, Tobacco Research / 19.08.2025
How Stimulants Affect the Brain’s Reward Pathway
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Photo courtesy of Freepik[/caption]
Stimulants are substances that increase brain activity, heightening alertness, energy, and focus. Common examples include caffeine, nicotine, and amphetamines. This article explores how these compounds activate the brain’s reward pathway and produce effects that can range from a gentle lift in mood to an intense short-lived “buzz” that reinforces repeated use.
Photo courtesy of Freepik[/caption]
Stimulants are substances that increase brain activity, heightening alertness, energy, and focus. Common examples include caffeine, nicotine, and amphetamines. This article explores how these compounds activate the brain’s reward pathway and produce effects that can range from a gentle lift in mood to an intense short-lived “buzz” that reinforces repeated use.
Dr. Lazarus[/caption]
Philip Lazarus, PhD
Boeing Distinguished Professor, Pharmaceutical Sciences
Professor, Dept of Pharmaceutical Sciences
College of Pharmacy and Pharmaceutical Sciences
Washington State University
Spokane, WA 99210
MedicalResearch.com: What is the background for this study?
Response: Smoking and tobacco use remains a major health issue. Smokers use cigarette over the course of the day because the levels of nicotine, the addictive agent in cigarettes and other forms of tobacco, dimmish with time in the bloodstream due to the breakdown of nicotine by enzymes in the body. By inhibiting the breakdown of nicotine in smokers, one would expect that the levels of nicotine would remain higher after smoking a single cigarette, and that these individuals may not require lighting up another cigarette so quickly, reducing the number of cigarettes smoked over the course of a day. This could have a profound effect on reducing the overall harm incurred from smoking or from using other forms of tobacco.
In a single previous study, smokers who used a CBD inhaler exhibited a 40% reduction in cigarette use. In addition, while cannabis users are often smokers, previous studies have indicated that they smoke less cigarettes than non-cannabis-using cigarette smokers. In previous studies published in 2021, we found that major cannabinoids present in cannabis like THC and CBD inhibit major metabolizing enzymes in our body, including several that are important in drug metabolism. We hypothesized that CBD and its major active metabolite, 7-hydroxy (OH)-CBD, may also be inhibiting one or more of the enzymes important in the metabolism (or breakdown) of nicotine.
Dr. Dai[/caption]
Dr. Hongying Daisy Dai, PhD
Professor and Associate Dean of Research
The College of Public Health
University of Nebraska Medical Center.
MedicalResearch.com: What is the background for this study?
Response: Tobacco use landscape has been changing in the United States with fewer combustible cigarette smokers and more e-cigarette and other emerging tobacco users. Nicotine concentration level is a key product characteristic of modern e-cigarette products and high-nicotine vaping devices have recently become available. This study seeks to examine whether biomarkers of exposure to tobacco-related toxicants have changed since 2013 among adult nicotine e-cigarette users, non-nicotine e-cigarette users, and cigarette smokers.
Dr. Han[/caption]
Meilan K Han MD, MS
Henry Sewall Professor of Medicine
Professor of Internal Medicine and Section Head
Division of Pulmonary and Critical Care Medicine, Medical School
University of Michigan
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: In the NIH sponsored SPIROMICS study we demonstrated that symptomatic, tobacco exposed individuals have frequent exacerbations. Many of these individuals are treated with the same inhaled medications that have shown benefit in COPD, but we don’t have any evidence basis for this practice.
Response: Cigarette smoking is one of the well-established causes of periodontitis, but the effect of using electronic cigarettes (e-cig), especially its long-term impact on periodontal health, is not yet clearly understood. Considering the increased popularity of e-cig use, especially among teenagers and young adults, and the known effect of high nicotine concentration in e-cigarette products, we conducted this clinical research to see if there were differences in periodontal health between e-cig users, traditional smokers, and nonsmokers. The study consisted of two visits, 6 months apart, where measures of oral and periodontal health were obtained.
Our data showed significantly greater clinical attachment loss in the e-cigarette users and cigarette smokers than in the non-smokers at both study visits. In only e-cigarette users, we observed an over 0.2 mm average increase in the clinical attachment loss after 6 months. 
Dr. Pierce[/caption]
John Pierce, PhD
Professor Emeritus
Department of Family Medicine and Public Health
Moores Cancer Center Director for Population Sciences
Co-leader of the Cancer Prevention program
UC San Diego
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Graphic Warning Labels are to be implemented in the US in July 2022, depending on litigation. This will be about 10 years after they were first proposed. Meanwhile, 120 other countries have implemented them already.
The FDA states that their purpose for the warnings is to provide a constant reminder to smokers about the health consequences of smoking, not to force them to quit.
In our study, 3 months of having cigarettes repackaged into graphic warning packs was associated with smokers thinking more about quitting and not getting as much pleasure out of their cigarettes. However, thinking about quitting is only the first step to conquering a nicotine addiction.
Dr. Lee[/caption]
Brian P. Lee, MD, MAS
Assistant Professor Clinical Medicine
University of Southern Californi
Keck School of Medicine
Los Angeles, California
MedicalResearch.com: What is the background for this study?
Response: The COVID-19 pandemic has been associated with mental health stressors, including anxiety, loneliness, and social instability. We hypothesized the pandemic may have led to increased alcohol and tobacco use as a coping mechanism for these stressors. National retrospective questionnaires had suggested higher reports of substance use, but these are limited by selection and recall biases, in addition to subjective report – we sought to address this knowledge gap by using a nationally-representative longitudinal cohort (Nielsen National Consumer Panel) tracking real-time purchases of households across the US. 
Dr. Silverstein[/caption]
Dr. Michael Silverstein M.D., M.P.H
Professor of Pediatrics
Director of the Division of General Academic Pediatrics
Vice Chair of Research, Department of Pediatrics
Boston University School of Medicine
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Tobacco use is the leading preventable cause of disease, disability, and death in the United States and quitting is one of the best things people can do for their health. Additionally, smoking during pregnancy can cause serious harms to both the pregnant person and the baby.
The Task Force continues to recommend that clinicians ask all adults and pregnant people about their tobacco use, advise those who use tobacco to quit, and connect them to proven, safe methods to help them quit. 
Dongmei Li, Ph.D.[/caption]
Dongmei Li, Ph.D., Associate Professor
Clinical and Translational Science Institute
University of Rochester Medical Center
MedicalResearch.com: What is the background for this study?
Response: Previous animal and human studies have found that nicotine exposure could harm adolescents’ brain development and impact their cognitive functions. Electronic cigarettes, which have become very popular among youth in the US in recent years, usually contain nicotine at equivalent or possibly higher levels than traditional tobacco cigarettes. Thus, it is reasonable to assume that vaping might be associated with self-reported cognitive complaints.
MedicalResearch.com: What are the main findings?
Response: Main findings from our study are:
Dr. Halpern-Felsher[/caption]
Bonnie Halpern-Felsher, PhD, FSAHM (pronouns: she/her)
Professor of Pediatrics
Taube Endowed Research Faculty Scholar
Professor (by courtesy), Epidemiology and Population Health
Professor (by courtesy), Psychiatry and Behavioral Sciences
Director of Fellows’ Scholarship, Department of Pediatrics
Director of Research, Division of Adolescent Medicine
Co-leader, Scholarly Concentrations, Pediatrics Residency Program
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: To examine adolescent and young adult e-cigarette use during the COVID-19 pandemic.
There were 4 main findings:
Dr. Al Rifai[/caption]
Mahmoud Al Rifai, MD, MPH
Cardiovascular Disease Fellow
Baylor College of Medicine Houston, TX
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Dr. Virani[/caption]
Salim S. Virani, MD, PhD, FACC, FAHA, FASPC
Professor, Section of Cardiovascular Research
Director, Cardiology Fellowship Training Program
Baylor College of Medicine
Staff Cardiologist, Michael E. DeBakey Veterans Affairs Medical Center
Co-Director, VA Advanced Fellowship in Health Services Research & Development at the Michael E. DeBakey VA Medical Center
Investigator, Health Policy, Quality and Informatics Program
Michael E. DeBakey Veterans Affairs Medical Center HSR&D Center of Innovation Houston, TX
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: E-cigarettes have gained popularity since their introduction in the U.S. market nearly 20 years ago and their use has increased especially among younger adults. On the other hand, public health efforts aimed at curbing tobacco use over the past few decades have resulted in a decrease in cigarette use. However, state-specific laws and regional cultural differences with regards to perception of these products may result in variability in tobacco use patterns. We therefore evaluate temporal changes in e-cigarette and cigarette use in each U.S. state between the years 2016 to 2018.
Dr. Al Rafai[/caption]
Mahmoud Al Rifai MD MPH
Section of Cardiology, Department of Medicine
Baylor College of Medicine Houston
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Response: The background for this study involves the associations of household rules and parental awareness with youth tobacco use using data from the Population Assessment Tobacco and Health Study. Health concerns regarding non-cigarette tobacco products, specifically e-cigarettes, have been on the rise. We wanted to explore whether parents are up to date with the trends of popular tobacco products today and what role they may play in youth tobacco cessation and prevention.
The main findings of the study revealed that parents less often suspected their children’s tobacco use if their children reported using only e-cigarettes, and other non-cigarette tobacco products, when compared with cigarettes. Additionally, we found that youth who agreed with their parents that their home has strict rules for tobacco use were less likely to initiate of tobacco use compared to youth who had different understanding of the rules from their parents or youth from households with more permissive household rules. 
Dr. Lanza[/caption]
Isabella Lanza, PhD
Associate Professor of Human Development
California State University, Long Beach
MedicalResearch.com: What is the background for this study? What are the main findings? Response: This is the first study to examine both nicotine vaping and cannabis vaping trajectories across adolescence and young adulthood, which allowed us to assess whether poly-substance vaping is common among adolescents and young adults. Poly-substance vaping (nicotine and cannabis vaping) was reported among a significant proportion of participants in the study (25% were identified as poly-substance vapers). For those that either escalated to frequent nicotine vaping use in adolescence or initiated frequent nicotine vaping use in young adulthood, the probability of engaging in cannabis vaping was very high (85%+).
Dr. Bandi[/caption]
Priti Bandi PhD
Principal Scientist, Risk Factors Surveillance Research
American Cancer Society, Inc.
Atlanta, GA 30303
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Trends in e-cigarette prevalence and population count of users according to cigarette smoking histories are unknown. These data are needed to inform public health actions against a rapidly changing U.S. e-cigarette market.
Dr. Obisesan[/caption]
Funmi (Abiru) Obisesan, MD, MPH
Postdoctoral Fellow
Johns Hopkins Ciccarone Center for the Prevention of Cardiovascular Disease
Postdoctoral Fellow
Johns Hopkins Ciccarone Center for the Prevention of Cardiovascular Disease
MedicalResearch.com: What is the background for this study?
Response: E-cigarettes are conceived by many individuals to be less harmful than combustible cigarettes, resulting in their use among young individuals and other vulnerable subpopulations. The recent outbreak of EVALI (e-cigarette, or vaping, product-use associated lung injuries) which was directly associated with e-cigarette use, and the rapidly evolving e-cigarette market, as well as regulations concerning them necessitates the need for up-to-date analyses of e-cigarette use trends. 
Dr. Hongying (Daisy) Dai[/caption]
Hongying (Daisy) Dai, PhD
Associate Professor
Department of Biostatistics | College of Public Health
University of Nebraska Medical Center
Omaha, NE
MedicalResearch.com: What is the background for this study?
Response: E-cigarette use increased dramatically from 11.7% to 27.5% for high school students and from 3.3% to 10.5% for middle school students during the periods of 2017 - 2019. In September 2018, the Food and Drug Administration (FDA) warned that youth e-cigarette use is reaching an epidemic proportion.
Exposure to secondhand aerosol (SHA) from e-cigarettes is not harmless as e-cigarettes aerosol contains nicotine and potentially harmful substances, including carbonyl compounds, TSNAs, heavy metals, and glycols. This study analyzed the 2015-2018 National Youth Tobacco Survey (NYTS) and the main findings are:
Dr. Villanti[/caption]
Andrea Villanti, PhD, MPH
Associate Professor
Department of Psychiatry
Vermont Center on Behavior and Health
University of Vermont
MedicalResearch.com: What is the background for this study?
Response: Our earlier work documented a significant association between first use of a flavored tobacco product and current tobacco use (
