Thalamus

Imagine your brain is like a city, and consciousness is like the city's power grid. After a really bad brain injury, it's not that the buildings (brain regions) are all destroyed — some of them are still standing, just with the lights off because the power lines connecting them got damaged. The thalamus is like the city's central power relay station. In this study, scientists implanted tiny electrodes deep in the brain of a man who had been in a minimally conscious state — barely aware of the world — for 6 years after a car accident. By sending small electrical pulses to his thalamus, they essentially 'turned the lights back on' in parts of his brain that had gone dark. During periods when the stimulator was switched on, he could do things he couldn't do before: follow instructions, use his limbs more purposefully, and even eat food by mouth. When they switched it off, those abilities faded. It's like finding out that some 'broken' appliances in the city just needed the power reconnected.