Researchers at the University of Manchester have created an interesting short film: it shows the brain losing consciousness under anesthesia. Working with a group of 20 subjects, the researchers took 100 scans per second to generate a “movie” of the brain, using a new brain recording strategy called fEITER (functional Electrical Impedance Tomography by Evoked Response.) While it’s fun to watch, it also might help determine the brain states of people with brain damage, and indicate recovery time and reaction to stimuli.
Before taking a look, it’s important to understand what’s being shown. The anesthesia works on changing the balance between excitation and inhibition of neuronal impulses. As the anesthesia takes effect, the brain will look more active–because the method used is measuring the action in the inhibitory circuits.
The researchers conclude that seeing this unique view of a patient under anesthesia indicates that consciousness is not like an on/off switch, but rather that there are multiple varying states of consciousness that are possible. You can read more details about this research in Time magazine.