Report: Immediate immune response observed upon viewing depictions of unwell individuals according to research findings
In a groundbreaking study published in Nature Neuroscience in 2025, researchers from Lausanne University Hospital (CHUV) and the University of Geneva (UNIGE) have discovered that exposure to sick-looking avatars in virtual reality (VR) can activate brain regions involved in threat detection and immune regulation, triggering a measurable immune response similar to that caused by real infections.
Key findings from the study include:
- Participants exposed to avatars displaying visible signs of infection (e.g., rashes like chickenpox) for about 15 minutes exhibited activation of brain areas such as the hypothalamus, which is linked to threat detection.
- Brain activity was monitored by electroencephalograms (EEG) and MRI scans, revealing heightened response in networks associated with threat anticipation and immune control.
- Blood tests showed the presence of immune markers typical of a real immune response, including increased activity of innate lymphoid cells (ILCs), which are part of the body's first immune defense line.
- Immune biomarker changes in participants exposed to VR sick avatars closely resembled those seen after vaccination, suggesting the brain can prime the immune system in anticipation of infection, even without physical pathogen exposure.
- Behavioral experiments showed participants' peripersonal space expanded, meaning they perceived the sick avatar as closer in a way that increased threat awareness and readiness to respond.
This demonstrates a novel neuroimmune communication, where the brain anticipates infectious danger by visual cues in VR and mobilizes immune defenses preemptively. Such findings could have therapeutic implications, such as enhancing vaccine efficacy or modulating immune responses through VR-based interventions.
However, it's important to note that the human immune system's reaction to real-world sick people remains unknown. The 2024 study adds to the understanding of the immune system's response to virtual sick avatars but does not provide insights into its reaction to real-world sick people. The immune system's response to real-world sick people, including potential secretory immunoglobulin A release, remains a topic for future research.
The study involved nearly 250 participants who were shown artificial faces with various expressions through a VR headset. Static images may not trigger the immune system response as observed in the virtual reality study. The closer the sick-looking face got to the person, the stronger the brain activity was, as measured during the study.
The 2024 study focused on the release of secretory immunoglobulin A in participants' saliva when approaching sick avatars. Changes could be observed in the blood drawn from the participants, with certain immune cells, known as ICLs (Innate Lymphoid Cells), being activated. An international research team from the University of Graz found that the immune system starts working in response to potential risks of infection. This suggests that the immune system prepares in advance when there's a potential risk of infection, requiring less energy when an infection occurs.
In summary, virtual reality exposure to sick-looking avatars can induce real biological changes: it activates specific brain circuits and stimulates the human immune system as if a real infection threat were present, illustrating a powerful psychosomatic mechanism between the brain and immunity. However, the immune system's response to real-world sick people remains a topic for future research.
[1] Nature Neuroscience [2] ScienceDaily [3] New Scientist [4] PLOS ONE [5] The Lancet
- The 2025 study published in Nature Neuroscience revealed that exposure to sick-looking avatars in virtual reality can trigger a measurable immune response similar to that caused by real infections, suggesting a novel neuroimmune communication.
- A 2024 study, published in ScienceDaily, focused on the release of secretory immunoglobulin A in participants' saliva when approaching sick avatars, demonstrating that the immune system starts working in response to potential risks of infection.
- The findings of the studies in Nature Neuroscience and ScienceDaily, along with other research in health-and-wellness, mental-health, fitness-and-exercise, and medical-conditions, suggest that virtual environments can have a significant impact on our health and wellness, including our immune responses.
