Consciousness is defined as the the state of being awake and aware of one’s surroundings; it’s the mind’s understanding that it exists, and it is one of the most elusive phenomena in all of human understanding. In an attempt to shed some light on this mystery, scientists are searching for a biological explanation they call the “neural correlates of consciousness”. In other words, the parts of your brain that generate self-awareness. And they may have found an essential component!
Researchers at the Allen Institute for Brain Science have uncovered three giant neurons, one of which is projected across the cortex of a mouse brain. They’ve traced these special neurons to the claustrum, believed to be one of the most densely connected parts of the brain. Scientists have hypothesized that the claustrum could be coordinating inputs and outputs to create conscious experiences. So seeing these three giant neurons extend from the claustrum was a big deal. The claustrum is a tiny sheet of neurons just below the cortex, and there’s one on each hemisphere of the brain. Scientists suspect the claustrum is a highly integrated region, and could have more anatomical connections than any other part of our brain. It’s potentially connected to many cortical areas that are crucial for perception, like vision, movement, and hearing. When studying the region, famous neuroscientist Francis Crick, (yes, one of the guys that discovered the structure of DNA) proposed that subjective consciousness is possible thanks to the claustrum, which could be acting like some kind of “conductor” in the mind. For instance, if your brain were an orchestra, he suspected the claustrum is responsible for keeping the myriad pieces and instruments playing together.
Crick explained this orchestration concept best when he described the experience of picking a rose. You can hold the rose in your hands, smell its fragrance, see its red petals and your mind processes this as a unified, subjective experience. The thing is, the claustrum conductor is just a hypothesis. But there was one recent study that gave brain scientists pause.
In 2014, a study was published detailing a woman with epileptic seizures who underwent deep brain stimulation. When electrodes near her left claustrum were stimulated, she immediately stopped what she was doing and stared blankly into space, she didn’t even respond to calls or gestures. When they turned off the treatment, she regained consciousness and didn’t even remember what happened! It was almost like they discovered an on-and off switch deep inside her brain! The claustrum could be the key to figuring this all out, but we don’t know for sure. Consciousness is still the ultimate enigma. Looking for connections in the brain also isn’t enough to explain whether consciousness is actually present. It’s more complicated that that.
Some of the brightest minds in physics think that consciousness is something the brain can’t ever solve, but we’ll leave that for the philosophers and scientists to fight over.