Research suggests a connection between positive thoughts and the body's immune system, potentially boosting natural defenses.
Scientists observed that individuals who utilized positive thinking to enhance activity in the brain's reward system exhibited an improved response to vaccination. Their immune systems produced a greater number of antibodies following the immunization shot compared to others.
This finding does not imply that optimism can cure diseases. However, it indicates a potential for mental strategies to support the immune system in combating infections and potentially suppressing tumors.
Professor Talma Hendler, from Tel Aviv University, stated this as the initial human demonstration suggesting a causal link: learning to engage the brain's reward system can increase immunization effectiveness.
Prior research had shown benefits of positive expectations in medical contexts, similar to the placebo effect. While animal studies linked brain reward system activation to stronger immune defenses, the evidence in humans was less conclusive.
For the study, healthy volunteers participated in brain training sessions. They employed various mental strategies to increase activity in specific brain regions, receiving real-time feedback on their progress.
Following four training sessions, volunteers received a hepatitis B vaccine. Blood samples collected two and four weeks later were analyzed for hepatitis antibodies.
The research indicated that participants who successfully boosted activity in the ventral tegmental area (VTA), a part of the brain's reward system, demonstrated the strongest immune response to the vaccine. These individuals achieved this primarily through positive expectations, such as envisioning favorable outcomes.
The observed effect could potentially be useful in strengthening patients' immune systems, though larger trials are necessary to confirm any clear medical benefit. Dr. Tamar Koren, a co-author, noted that the team is investigating whether other immune system components, such as those involved in inflammation, are also affected.
Dr. Nitzan Lubianiker, a senior author of the study, clarified that the tested approach is intended as a complementary tool to enhance immune responsiveness to vaccination. It is not designed to replace vaccines or standard medical care.
Professor Jonathan Kipnis of Washington University in St Louis concurred, stating it is premature to draw conclusions about clinical relevance. He added that if significant clinical effects were demonstrated in larger trials, they would likely complement existing treatments.
Professor Jeremy Howick from the University of Leicester commented on the small observed effect and cautioned that sick patients might respond differently in a clinical setting. Nevertheless, he highlighted the value for healthcare professionals in fostering positive expectations through statements like, "We're going to do our best to take care of you," or, "I've seen this treatment work for people like you," suggesting this approach is beneficial.