Origin and Mechanisms of Hallucinations  1970, pp 275-276

Hyperventilation and Hallucinations

T. E. Allen

Abstract

In January 1967 while working in the Federal Bureau of Prisons at a Youth Center, Dr. Agus and myself had the experience of seeing two interesting cases in which hyperventilation led to hallucinations on repeated occasions.

The exact pattern in which symptoms developed was different in each patient, but developed in the same sequence in the same patient. Furthermore, each stage in the sequence was discrete and could exist without necessary progression if the hyperventilation were stopped at that point. It could also be terminated by a maneuver which induced apnea, e.g. stimulation of the oculovagal response or a Valsalva maneuver.

The hallucinations occurred without disorientation or loss of contact with the environment. The pattern of hyperventilation (a period of deep sighing respirations followed by panting respirations) as well as position i.e. standing or seated and temporal relationship to meals were considered to be important determinents. The content of the hallucinations is certainly related to dynamic considerations.