Altered sensory environments, altered states of consciousness and altered-state cognition

Presents a theoretical formulation of the concept of an altered state of consciousness (ASC) that considers 3 major issues: (1) the phenomenon, (2) its method of induction, and (3) criteria for evaluating the phenomenon. It is not clear that an ASC mental state is related to subjective experience and cognitive functioning. The relationship between the method of induction and the resulting ASC is also unclear at present, and criteria for determining and evaluating the ASC are indistinguishable from the phenomenon itself, leaving the latter ill-defined. It is proposed that different states of consciousness entail different modes of cognition.