Stanford researchers have pinpointed a specific brain region responsible for anchoring us in our physical bodies.
When disrupted, this area—called the anterior precuneus—can launch us into the bizarre realm of out-of-body experiences.
Meanwhile, an Australian anatomist has identified an entirely new brain structure that could be unique to humans, potentially explaining our distinctive cognitive abilities.
These findings aren’t just academic curiosities. They could revolutionize treatments for conditions ranging from epilepsy to Parkinson’s disease, while answering fundamental questions about human consciousness.
Your Brain’s Anchor to Reality
When Dr. Josef Parvizi, a neurology professor at Stanford, encountered a patient with epilepsy describing strange symptoms, he knew he was onto something significant.
The patient reported: “My sense of self is changing, almost like I am a third observer to conversations that are happening in my mind that I’m not part of. Plus, they just feel like I’m floating in space.”
What Parvizi and his team discovered was remarkable. A sausage-shaped piece of brain tissue called the anterior precuneus, hidden in the valley between your brain’s hemispheres, serves as the control center for your physical self-awareness.
This region helps you understand that your thoughts, perceptions, and body belong to you—not someone else.
When Parvizi’s team electrically stimulated this specific area in eight patients, every single one reported changes in their sense of physical self. Some described floating sensations, others felt completely disconnected from their bodies.
The study, published in the journal Neuron, concluded that the anterior precuneus serves as our brain’s anchor to physical reality.
“We think this could be a way for the brain to tag every experience in the environment as mine,” explains Christophe Lopez, a researcher at the National Center for Scientific Research in France.
When Your Brain Gets Confused
Here’s where conventional thinking gets turned upside down: out-of-body experiences aren’t just psychological phenomena or random neural misfirings. They happen when your brain receives conflicting sensory information about your body’s position in space.
The anterior precuneus processes signals from your inner ear, which tracks your body’s motion and position. When these signals contradict what your eyes see—for instance, your inner ear senses movement while your eyes register stillness—your brain faces a sensory dilemma.
And sometimes, the brain’s solution to this confusion is to place your consciousness outside your body entirely.
This explains why these experiences can occur during seizures, when taking certain drugs like ketamine, or during electrical stimulation of this brain region. Each scenario disrupts the normal functioning of the anterior precuneus.
The Missing Piece: A Newly Discovered Brain Region
While Stanford researchers were mapping the brain area responsible for out-of-body experiences, Professor George Paxinos at Neuroscience Research Australia (NeuRA) was confirming the existence of an entirely new brain structure that had eluded scientists until now.
After suspecting its existence for nearly 30 years, Paxinos finally identified what he named the Endorestiform Nucleus using cutting-edge staining and brain imaging techniques.
This discovery comes as a shock to the neuroscientific community. How could an entire brain region remain undetected in the most studied organ in the human body? The answer lies in both its location and our technological limitations.
The Endorestiform Nucleus is situated in the inferior cerebellar peduncle, a region at the base of the brain where the spinal cord and brainstem connect. This area plays crucial roles in fine motor control and sensory processing.
What makes this discovery particularly intriguing is that this structure appears to be unique to humans or at least more prominent in humans than other species. This suggests it could be involved in distinctly human capabilities, possibly including our unique form of self-awareness.
Self-Awareness and Human Uniqueness
These two discoveries – the anterior precuneus’s role in bodily self-awareness and the identification of the Endorestiform Nucleus – raise fascinating questions about human consciousness.
Could these brain regions work together? Might the Endorestiform Nucleus contribute to the complex self-awareness that allows us to conceptualize our physical presence in space – the very ability that goes haywire during out-of-body experiences?
While researchers haven’t yet established a direct connection between these two brain areas, the timing of these discoveries opens new avenues for understanding how the brain generates our sense of self.
The human brain contains approximately 100 billion neurons with an information processing capacity we’re only beginning to comprehend. These findings suggest we’re still in the early stages of mapping this incredibly complex organ.
Beyond Floating: Medical Applications
The implications of these discoveries extend far beyond explaining weird brain experiences. Patrick Purdon, a Harvard researcher studying ketamine’s effects on the brain, notes that the anesthetic drug appears to disrupt the anterior precuneus – much like electrical stimulation does.
This raises an intriguing possibility: could targeted electrical stimulation replace anesthetic drugs like ketamine?
“You could get the specific brain areas that you want without having to cause a brain-wide and system-wide effect that might carry with it a lot of side effects,” Purdon suggests.
Even more promising is the potential connection to depression treatment. Ketamine has shown remarkable effectiveness as an antidepressant. If stimulating the precuneus could reproduce ketamine’s effects without the drug itself, we might have a new approach to treating depression.
Similarly, Professor Paxinos believes his discovery of the Endorestiform Nucleus could inform treatments for neurological diseases such as Parkinson’s and motor neuron disease.
“The atlases that I have produced of the human brain and spinal cord are like Google Maps for surgeons and other neuroscientists—and a detailed understanding of neuroanatomy is crucial to treating neurological disorders,” Paxinos explained.
The Dual Nature of Self
The research from Stanford highlights something profound about human consciousness: our sense of self has multiple components. The PMC (posteromedial cortex) region, which includes the anterior precuneus, contributes to both our narrative self and our physical self.
Your narrative self is your internal autobiography – the story you tell about who you are, your memories, and your personal history. Your physical self is your awareness of occupying a specific point in space and time.
Most of us take this physical self-awareness for granted. As Parvizi puts it: “As you are sitting in your chair, you have an understanding that it is you looking at me, your point of view in space and in your environment.”
But for some – like patients with neurological conditions or those experiencing drug effects – this fundamental sense can temporarily dissolve.
When Self Becomes Untethered
Out-of-body experiences have been reported across cultures throughout history. They’re often associated with near-death experiences, deep meditation, and certain psychological states.
Some people describe floating above their physical body, watching events unfold below. Others report traveling to different locations entirely.
While these experiences have often been interpreted as spiritual or supernatural, Stanford’s research offers a neurological explanation. When the anterior precuneus malfunctions – whether due to seizure activity, drugs, or electrical stimulation – our physical self becomes untethered.
The brain, struggling to reconcile conflicting sensory information, creates the perception that consciousness has separated from the body.
This doesn’t diminish the profound impact these experiences can have. Many people report life-changing insights and perspective shifts after out-of-body experiences, regardless of their cause.
The Uniquely Human Brain
Professor Paxinos’s discovery of the Endorestiform Nucleus adds another layer to this discussion. If this brain region is indeed unique to humans or more developed in humans than other species, it could help explain our distinctive cognitive abilities.
Humans possess an unusually sophisticated sense of self-awareness – not just recognizing ourselves in mirrors like some other species, but contemplating our own existence, imagining future scenarios, and even questioning the nature of consciousness itself.
Could the Endorestiform Nucleus contribute to these uniquely human traits? While it’s too early to say with certainty, the location of this structure in an area associated with sensory processing and motor control suggests it could play a role in how we perceive and interact with our environment.
Mapping the Mystery of Consciousness
Understanding the neural basis for out-of-body experiences and identifying new brain structures opens doors to fascinating research possibilities. If scientists can reliably trigger and study these states, they might gain new insights into consciousness itself.
The research also highlights the incredible complexity of our brains. A small region hidden between our brain hemispheres plays a crucial role in one of our most fundamental experiences – the sense that we exist within our bodies.
Meanwhile, an entirely new structure has been discovered in an organ scientists have been studying for centuries.
These findings add to our growing understanding of the neural correlates of consciousness – the specific brain activities that correspond to conscious experiences. By mapping these correlates, scientists inch closer to answering the hard problem of consciousness: how physical brain processes give rise to subjective experience.
Beyond Medicine
These discoveries have implications beyond medicine and neuroscience. Philosophers have long debated the nature of self and consciousness. This research provides empirical evidence that our sense of embodiment depends on specific brain mechanisms that can be disrupted.
For virtual reality developers, understanding how the brain creates our sense of embodiment could lead to more immersive experiences. If we know what neural signals create the feeling of being present in our bodies, perhaps we can better trick the brain into feeling present in virtual ones.
For those studying altered states of consciousness – whether induced by meditation, psychedelic substances, or other means – this research provides a physiological framework for understanding certain aspects of these experiences.
The Future of Brain Research
These discoveries mark significant steps forward in our understanding of consciousness and self-awareness. But as with all groundbreaking research, they raise as many questions as they answer.
How does the anterior precuneus interact with other brain regions—possibly including the newly discovered Endorestiform Nucleus—to create our sense of self? What role might these regions play in conditions like depersonalization disorder, where people chronically feel detached from their bodies and thoughts? Could targeted stimulation help treat such conditions?
As neuroscientists continue mapping the brain with increasingly sophisticated tools, we may find answers to these questions and many more. The human brain, despite centuries of study, still holds countless secrets about how it generates our conscious experience.
A Personal Connection
Out-of-body experiences, while scientifically fascinating, are also deeply personal for those who experience them. Whether occurring during a seizure, under anesthesia, or in a near-death situation, these episodes often leave a lasting impression.
Understanding their neural basis doesn’t diminish their significance. Instead, it adds another dimension to our appreciation of the brain’s remarkable capacities.
For patients with certain forms of epilepsy, knowing that their strange sensations of disembodiment have a physical cause might provide some comfort. For researchers developing new treatments for neurological conditions, this knowledge offers new potential targets.
These discoveries remind us that even as we uncover the physical mechanisms behind our most profound experiences, the subjective nature of consciousness remains one of science’s greatest mysteries.
References
- Hamilton, J. (2023, July 3). Scientists have found part of the brain that triggers out-of-body experiences. NPR.
- Newman, T. (2018, November 26). New brain region ‘could be what makes humans unique’. Medical News Today.
- Parvizi, J. et al. (2023). Neural correlates of physical self-awareness in the anterior precuneus. Neuron.
- Paxinos, G. (2018). Human Brainstem: Cytoarchitecture, Chemoarchitecture, Myeloarchitecture.
