"Reality tunnel" is a counselling phrase used by Richard Gannon that is also a model for physiological organic neurology. It's even a pretty good concept for understanding religious commitment. But is NOT religion. In our time religion is an institution with a bureaucracy and a name. This phrase is just a suggestive idea. The concept really was developed by Robert Anton Wilson. It's a pretty good example of using metaphors as extended at length by Lakoff and Johnson. It is embodied thought.
"Through his writings and lectures, Wilson became—alongside the likes of Timothy Leary, Alan Watts, Terence McKenna—a giant of American counterculture. He described his work as an “attempt to break down conditioned associations, to look at the world in a new way, with many models recognized as models or maps, and no one model elevated to the truth”. His goal being “to try to get people into a state of generalized agnosticism, not agnosticism about God alone but agnosticism about everything.”
Before Wilson, Timothy Leary used the phrase. He suggested that LSD had the power to break open "reality tunnels" and that is what users describe. If a person were not a drug user, two phenomena could open up the tunnel width. One is experience and the other is story. Both are powered by curiosity and empathy.
Time and the close metaphors of path or way are what can be construed as the tunnel, pushing us through the darkness along whatever the track our families or schools or jobs have laid out under our wheels. We cannot explode the tunnel entirely without risking madness but we can make it wide -- or "put in windows". Humans can only take in and manage a limited amount of information and does it by filtering, suppressing and ignoring a great deal, What remains is our "reality,"
Humans hate change. Since time brings change, people resist both, even as their own bodies morph. One of the other deep primal metaphors is that of the axis mundi of ourselves and our consciousness as the center of all consciousness. Around us is a kind of circular area, mapping what we know. Everyone has a boundary, the same as everyone has a tunnel. They are our reality. Outside that boundary are the dragons. Some of us would like to interview them.
Mircea Eliade discussed the idea of a center (nucleus) in a circle as a more natural schematic than a cross on a hill, the Christian schematic. If one adds attachment to the center, one has the three primal elements of story. Imagine a girl so attached to a life in a small circle that she would die rather leave, so she remains a child. Imagine a boy whose unreliable mother taught him to always move on, so that his only satisfaction is in war.
Now try to imagine what might break through the wall of the tunnel and give them a new reality. Such an event might be considered sacred.