The stark World War II prose of James Jones in The Thin Red Line remind us of what happens to the psyche when everything else is stripped away:

He heard the soft “shu-u-” of the mortar shell for perhaps half a second. There was not even time to connect it with himself or frighten him, before there was a huge sunburst roaring of an explosion almost on top of him, then black blank darkness. He had a vague impression that someone screamed but did not know it was himself. As if seeing dark film shown with insufficient illumination, he had a misty picture of someone other than himself  half-scrambling, rolling down the slope. Then nothing. Dead? Are we, that other one is I? am he? “Am I hit? Am I hit?”

“Yes,” Train mumbled. “Y-you are.” He also stuttered. “In the head.”

“Am I?” Fife looked at his hands and found them completely covered with the wet red. He understood now that peculiar red haze. Then terror blossomed all through him like ballooning great fungus, making his heart kick and his eyes go faint.