In a recent study, the University of Wisconsin-Madison stimulated the ‘central lateral thalamus’ in “anesthetized macaques [monkeys] and effectively restored arousal and wake-like neural processing”. The monkeys then returned to an unconscious state after the stimulation ceased. How did they come up with this idea?
There’s a particularly essential part of our brains called the thalamus. The thalamus is like the “Grand Central Station of the brain” (SingularityHUB). Its central location and connections to the rest of the brain allow it to rapidly process and send/receive a lot of information, such as relaying sensory information. Therefore the researchers believe that the thalamus is a necessary component of the brain for supporting consciousness. So what’s the magic frequency?
It turns out that “the speed of a firing central lateral neuron” (found in the thalamus) normally rests at around 50hz or 50 cycles a second in a conscious brain, therefore the researchers postulated that this rate is also largely responsible for maintaining consciousness. To test their hypothesis they electrically stimulated the anaesthetized monkey’s brains at 50hz and shockingly the monkeys opened their eyes, changed their expressions and displayed other normal waking functions. This is likely another case of brainwave entrainment, whereby the rate of neuron firing in the brain syncs to an external stimulus, and therefore it's possible that sound could also be used to the same effect.
The full range of possibilities stemming from this discovery remains open ended, however one area for further study will certainly be looking into waking patients from a comatose state.
You can find the original study here.
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