The term hypnotic blindness refers to the notion of hypnosis, which is in turn indebted to the Greek noun hupnos (sleep). It is used to denote a hypnotically induced failure to consciously perceive an object or stimulus which is present in the external world and which lies within the subject's field of vision. This failure to perceive is traditionally designated as a " negative hallucination. Conceptually as well as phenomenologically, hypnotic blindness differs from true " blindness in that it is transient and reversible, that it can be evoked by suggestion, and that the resulting 'blindness' tends to confine itself to a segment of the visual field (notably a physiologically unlikely segment). Following a hypnotist's suggestion, the individual may be exclusively blind for an object or person within his range of vision. A further phenomeno-logical difference between hypnotic blindness and true blindness is that the implicit or unconscious perception of the object or stimulus may remain intact, as can be inferred from priming tests. This is the reason why hypnotic blindness is usually conceptualized as a failure of conscious visual perception.
References
Mack, A., Rock, I. (1998). Inattentionalblindness. Cambridge, MA: MIT Press.
Dictionary of Hallucinations. J.D. Blom. 2010.