A groundbreaking study published online in Nature Neuroscience on July 28, 2025, reveals that the human brain can predict virtual infection threats and mount an immune response—even without actual exposure to a pathogen.

In the experiment, participants wearing virtual reality (VR) headsets were presented with “infectious avatars”—faces showing clear signs of illness—within their peripersonal space (PPS), the immediate zone surrounding the body. Compared with neutral or fearful avatars, these infectious avatars elicited immediate avoidance behaviors and faster multisensory (touch+visual) reaction times, suggesting early threat detection by PPS neuron circuits.

Using EEG and fMRI, researchers identified activation in fronto–parietal PPS regions and broader salience networks. Crucially, subsequent blood tests revealed immune activation: researchers measured changes in innate lymphoid cells (ILCs) and natural killer (NK) cell frequencies—markers typically associated with early innate immune response—triggered solely by the visual anticipation of infection in VR, comparable to the effects of receiving a flu vaccine.

This study challenges traditional views on the separation between neural threat detection and physiological immunity. The findings reveal an integrated “neural–immune loop” capable of priming immune readiness before physical exposure, suggesting evolutionary mechanisms built into social species to avert disease. Clinical implications could range from mental health to preventive therapies targeting the neural interface of immune activation.