Autism, amnesia, hippocampus, and learning.

Autism is held to be the result of the failure of a central cognitive processor which is necessary for flexible multidimensional association of sensorial stimuli, memory, and motivational states. Failure of this processor produces rigid, invariant, rote behavior, thought and language and aberrant modulation of emotion. It is argued that this central processing function is critically dependent on the hippocampus. Thus autism is postulated to be the developmental syndrome of hippocampal dysfunction. The hippocampus is postulated to be necessary for normal development in the child of language syntax, semantics, and pragmatics; the capacity for creativity and generativity in language and behavior, and combinatorial possibilities in general; for the integration of motivational states with experience and learning; and for the construction of a complex, useful and flexible structure of meaning. These constructs may become independent of hippocampus for use, but hippocampus is still required to modify or add to them. Finally, this analysis suggests a specific hypothesis of hippocampal organization which I advance as an hypothesis: that the hippocampus can be modelled as a multidimensional system in which the unique intersection of all input dimensions is the resultant.