ABSTRACT
The findings of this research suggest that the following parts of the human brain are centrally implicated in the normal process of dreaming: the limbic system, the medial occipito-temporal cortex, the inferior parietal convexity, and the connections between mediobasal frontal cortex and brainstem and diencephalic–limbic structures. Damage to these regions of the brain produces definite and specific effects on the subjective experience of dreams. On the other hand, the following parts of the nervous system appear to be inessential to the normal dream process, or even to be inhibited during dreaming: the spinal and peripheral sensory-motor systems, primary (idiotypic) sensory-motor cortex, unimodal (homotypical) isocortex outside of the visual sphere, and dorsolateral prefrontal cortex. Damage to these structures has no appreciable effect upon the subjective experience of dreams. The following formulation can be advanced on the basis of these findings: the essential nature of the dream process is determined by the concerted functioning of the former group of structures in the absence of a contribution from the latter group of structures. The role of the remaining regions of the brain is unclear, but it seems likely that activation or inhibition of these regions does not play a fundamental role in the normal process of dreaming.
