Scientists recently discovered that rhythmic brain waves, called alpha oscillations, help your brain tell the difference between your own body and the outside world. A new study from Karolinska Institutet in Sweden, published on January 12, 2026, reveals that the speed of these alpha waves, especially in the parietal cortex, determines how precisely you feel your body parts belong to you. This fundamental brain process shapes our continuous experience of being embodied.[news+4]
The Brain's Complex Self-Perception
Feeling that your hand is truly yours might seem automatic. However, the brain constantly works to integrate sensory signals to create this sense of "body ownership." This complex process allows us to interact properly with the environment and forms a key part of our self-consciousness.The brain combines information from various senses, including vision, touch (tactile), and proprioception, which is the sense of your body's position in space.[pmc+19]
To study body ownership, researchers often use an experiment called the "rubber hand illusion." In this classic setup, a person's real hand is hidden from view while a lifelike rubber hand is placed in front of them. When both the hidden real hand and the visible rubber hand are stroked at the same time, many participants start to feel that the rubber hand is actually part of their own body.If the stroking is out of sync, this feeling of ownership quickly fades.The brain gets fooled into remapping its body image to include the artificial hand.[academic+16]
Alpha Waves Act as a "Self" Filter
The recent Karolinska Institutet study, involving 106 participants, found that the frequency of alpha waves in the parietal cortex plays a critical role in this illusion. The parietal cortex is the brain region responsible for processing sensory information from the body.[news+3]
Mariano D'Angelo, a lead author and researcher at the Department of Neuroscience, Karolinska Institutet, explained that they identified a "fundamental brain process" that shapes our continuous experience of being embodied.The study showed that people with faster alpha frequencies were more sensitive to small timing differences between what they saw and what they felt. Their brains processed sensory information with greater accuracy, leading to a more precise sense of body ownership.[news+8]
Conversely, slower alpha frequencies were linked to a "broader temporal binding window." This means the brain was more likely to treat asynchronous visual and tactile signals as if they happened together. This reduced timing precision made it harder for the brain to separate self-related sensations from external ones, weakening the distinction between the body and the outside world.[news+4]
Brain Regions and Sensory Integration
Multiple brain areas work together to create the sense of body ownership. Cortical regions, located in the outer layer of the brain, include the ventral premotor cortex, the posterior parietal cortex (including the intraparietal sulcus), the insula, and the somatosensory cortex.These areas are crucial for integrating the different sensory inputs. For example, the insula helps combine external sensory information with internal bodily signals to support the subjective experience of the body.[academic+8]
Beyond the cortex, subcortical structures also play a role. These deeper brain areas include the cerebellum, putamen, amygdala, thalamus, and hippocampus.The cerebellum, for instance, shows increased activity that matches the intensity of the rubber hand illusion.[pmc+4]
The integration of various senses is key. Visual information from seeing a body part, tactile signals from touch, and proprioceptive signals from muscles and joints all contribute.Interoception, which is the sense of the body's internal physiological condition, such as heartbeat and affective touch, also plays a role in establishing body ownership.[pubmed+10]
Real-World Impact and Future Research
Understanding how the brain defines body ownership has important implications for various fields. For psychiatric conditions like schizophrenia, where a person's sense of self can be disturbed, these findings offer new insights into underlying brain processes.[news+3]
Furthermore, this research could lead to advancements in technology. Henrik Ehrsson, a professor at the Department of Neuroscience, Karolinska Institutet, and senior author of the study, noted that the findings could help develop better prosthetic limbs.It could also improve the realism of virtual reality experiences by making virtual body parts feel more like one's own.[sciencedaily+1]
The brain's ability to constantly evaluate and integrate sensory information allows us to maintain a stable and coherent sense of our own body, distinguishing it from everything else in the world.[sciencedaily+1]
