Observations placeholder

Dr Hebb’s experiments



Type of Spiritual Experience


Some of the earliest research on the effects of sensory deprivation was carried out by Donald Hebb, a Canadian psychologist who was influential in the area of neuropsychology.  After getting his PhD at Harvard in the effects of sensory deprivation in rats, Hebb  applied to work with Wilder Penfield at the Montreal Neurological Institute. Here,  in 1937, he researched the effect of brain surgery and injury on human brain function. From this, he deduced the prominent role that external stimulation played in the thought processes of adults. In fact, the lack of this stimulation, he showed, caused diminished function and sometimes hallucinations [and more]

This photograph shows a subject undergoing one of Dr. Hebb’s sensory deprivation experiments. As it said in the caption
“In it the subject is blindfolded, their hands are encased, and their auditory capability has been removed. They are also covered by a blanket, which can be removed and then replaced to control their body temperature and further disorient them (which is also the reason why their hands and feet are covered)”



A description of the experience

Raynor C Johnson – Watcher on the Hills

A very different kind of ill treatment of the body-mind has been recently studied experimentally by Professor Donald Hebb at McGill University.  He tested human beings’ ability to endure stimulus starvation.  The experimental subjects were placed in an air-conditioned chamber in silence, with opaque goggles over their eyes and arm restraints.  Very few subjects could tolerate these conditions for more than twenty-four hours and the limit was seventy-two hours.

They produced emotional distress and hallucinations of seeing, hearing and touching.

The visual hallucinations appear to have been elaborate changing geometrical patterns and fantastic moving imagery similar to that found through taking drugs such as mescalin or LSD.  One man had a feeling of bi-location, presumably a form of astral projection [out of body experience].

The source of the experience

Ordinary person

Concepts, symbols and science items



Science Items

Activities and commonsteps



Sensory deprivation