Can positive anticipation that activates the brain's reward system strengthen the body's immune defenses? A new study by Tel Aviv University, the Technion, and Tel Aviv Medical Center (Ichilov), published in the prestigious journal Nature Medicine, provides the first evidence in humans that brain activity associated with the expectation of reward has a measurable effect on the body's response to a specific vaccine.
Training the Brain's Reward SystemThe study was conducted through a collaboration between two research groups: the laboratory of Prof. Talma Hendler, from the School of Psychological Sciences and the Gray Faculty of Medical and Health Sciences, together with her former PhD student Dr. Nitzan Lubianiker, at Tel Aviv University and the Sagol Brain Institute at Tel Aviv Medical Center (Ichilov); and the laboratory of Prof. Asya Rolls from The George S. Wise Faculty of Life Sciences, together with her former student Dr. Tamar Koren of the Technion and the Department of Pathology at Tel Aviv Medical Center (Ichilov).
Eighty-five healthy volunteers participated in the experiment. Some underwent special brain training using fMRI neurofeedback technology - a method that enables individuals to learn, in real time, to regulate activity in specific brain regions through reinforcing learning. The aim of the brain training was to increase activity in a key region of the brain's reward system including the Ventral Tegmental Area (VTA), which is responsible for dopamine release in the context of mental activity related to the expectation of positive outcomes and motivation to obtain rewards. Participants were instructed to modulate their brain activity using various mental strategies (e.g. thoughts feelings memories) while monitoring positive feedback about the strategy that was saucerful in regulating their brain.
Left to right: Dr. Tamar Koren & Prof. Asya Rolls , Photo credit: Nitzan Zohar
From Brain Activation to Antibodies
Immediately after completing the brain training, all participants received a hepatitis B vaccine. The researchers then tracked the immune response through a series of blood tests, measuring levels of specific antibodies produced following the vaccination.
The results showed that participants who succeeded in significantly increasing activity in the brain's reward region also demonstrated a greater increase in antibody levels after vaccination. The association was specific to the VTA and was not observed in other brain regions used for control purposes (such as the hippocampus), nor in other reward-system areas linked to different reward-related experiences such as pleasure and satisfaction. In other words, the effect was both anatomically and mentally specific.
Dr. Nitzan Lubianiker, photo credit: Sameer Khan/Fotobuddy
The Role of Positive Anticipation
Furthermore, an in-depth analysis of the mental strategies participants used during training of the VTA (and not other regions) revealed that those who focused on positive anticipation - feelings of excitement, belief in a good outcome, or the expectation of something positive about to happen (such as a favorite food or a long-awaited meeting) - were able to maintain higher VTA brain activity over time, which was also associated with a better immune response. In other words, the researchers identified a link between reward-system brain activity, a mental state of positive anticipation, and the body's response to an immune challenge.
According to the research team, this is not "positive thinking" in the popular sense or a New Age slogan, but a measurable neurobiological mechanism - related, among other things, to the well-known placebo effect in medicine (a therapeutic response beyond a specific medical intervention). "We show that mental states have a clear brain signature, and that this signature can influence physiological systems such as the immune system," explain the researchers.
While the study does not propose a substitute for vaccines or medical treatment, it opens the door to new, noninvasive approaches that may one day strengthen immune responses, improve the effectiveness of medical treatments, and even contribute to fields such as immunotherapy and the treatment of chronic immune pathologies. The researchers note that the study's findings underscore a broader message: the mind-body connection is not merely a theoretical concept, but a real biological process that can be measured, trained, and potentially harnessed to promote better health.
Prof. Talma Hendler, Photo credit: Tel Aviv Medical Center (Ichilov).
Implications for Medicine and Health
The research team adds that the findings highlight the potential inherent in integrating neuroscience, psychology, and medicine. "Our study shows that the brain is not only a system that responds to the body's state of health, but also an active player that influences it," say Prof. Talma Hendler, Prof. Asya Rolls, Dr. Nitzan Lubianiker, and Dr. Tamar Koren. "The ability to consciously activate brain mechanisms associated with positive anticipation opens a new avenue for research and future treatments - as a complement to existing medicine, not as a replacement. In the future, it may be possible to develop simple, noninvasive tools to help strengthen immune responses and enhance the effectiveness of medical treatments by relying on the brain's natural capacity to influence the body. However, it is important to emphasize that activation of the reward system and its effect on immune response vary between individuals. Therefore, this approach cannot replace existing medical treatments, but may well serve as an additional supportive component."
