One is normal brain development, and the other is consciousness itself. It’s true that a human being needs certain external stimuli for the brain to develop in a healthy way and for mental experience to be normal and stable. But that does not mean that, without those stimuli, consciousness does not exist.
Human beings require external stimuli for any higher brain development to happen, not just healthy brain development.
But that does not mean that, without those stimuli, consciousness does not exist.
Yes.... It does. Any example you would like to share of a conscious individual who lacks access to any and all external stimuli?
A person can still be conscious and yet suffer severe cognitive, emotional, or behavioral changes because of sensory deprivation or an extremely limited environment.
Yes, but they did not develop in that extreme deprivation. And even if they did develop in a way that was restricted, they did not lack external stimuli completely.
Your body literally need to be experience external stimuli to develop the capacity for consciousness.