I call it a touchpoint. If you know another term for it, do tell. In the mildly-insane-aren't-we-all? world my characters inhabit, they must have that one thing that grounds them. A connection to a place or a person that renders them the most sane person on Earth. The same route to and from work traveled for twenty years. A mentally disabled brother. A cactus he stares at every morning at breakfast. Therein lies moments of clarity and truth and rightness the character experiences nowhere else. Moments that belong to everyone and no one. A shared burden the reader buys into because she has her touchpoints, too.
The protagonist in my novel The Night Caller flirts with insanity. He is an agoraphobic, broken soul who is an unreliable narrator, at best. If I would have left him at this, the reader would have gladly poured that cup of crazy down the sink. I had to find a way to get the reader on-board with him, root out a growing interest in his goals, take ownership of their alliance to him, for that is when the magic of a psychological suspense happens. His touchpoint is restoring wood. Not merely a carpenter's hand, but that of an artisan who appreciates the way things were, how good they can be again. He sands with small, purposeful strokes of clarity in his otherwise crumbling reality. He strives for the simplicity in the way things once were. Who hasn't longed for that at least once?
In one of my favorite Peter Abrahams novels, The Last of the Dixie Heroes, the protagonist descends into the sub-culture of Civil War reenactors who have lost touch with reality. His touchpoint? A son. Ultimately, his savior.
What are some of your favorite character's touchpoints?