The thalamus plays a role in our sense of reality, of what is real.  It connects emotional meaning to our conception of God.  It is largely responsible for helping us feel that God is real in an objective sense.  Of enormous consequence, the more you strengthen an idea over and over, the brain responds as if the idea is real within the world.  The thalamus doesn’t make a distinction between inner and outer realities.  Belief can become neurologically real, for better or worse.

“Now, you’d expect a heavy flow of information from the thalamus to the visual cortex, and there is. But there’s six times as much traffic flowing in the opposite direction, and that dwarfs the amount coming in from the eyes. And that suggests that in any one moment what we experience as seeing relies less on the light streaming into our eyes and more on what’s already inside our heads.”

Eagleman, D. (2016). What is Reality? Edited transcript of Episode One of The Brain with David Eagleman, London: Blink Films. (28:36-29:31).