http://frontiersin.org/neuroscience/paper/10.3389/neuro.01/1.1.006.200
7/html/ (that was intended as a hyperlink, but also read below:)

The Intense World Syndrome - an alternative hypothesis
for autism
Henry Markram, Tania Rinaldi and Kamila Markram∗
Brain Mind Institute, Ecole Polytechnique FeŽ deŽ rale de Lausanne,
Switzerland
Review Editors: Joseph LeDoux, Center for Neural Science, New York
University, USA
Jacqueline N. Crawley, Laboratory of Behavioral Neuroscience,
National Institute of Mental Health, USA

Autism is a devastating neurodevelopmental disorder with a
polygenetic predisposition that seems to be triggered by multiple
environmental factors during embryonic and/or early postnatal life.
While significant advances have been made in identifying the neuronal
structures and cells affected, a unifying theory that could explain
the manifold autistic symptoms has still not emerged. Based on recent
synaptic, cellular, molecular, microcircuit, and behavioral results
obtained with the valproic acid (VPA) rat model of autism, we propose
here a unifying hypothesis where the core pathology of the autistic
brain is hyper-reactivity and hyper-plasticity of local neuronal
circuits. Such excessive neuronal processing in circumscribed
circuits is suggested to lead to hyper-perception, hyper-attention,
and hyper-memory, which may lie at the heart of most autistic
symptoms. In this view, the autistic spectrum are disorders of hyper-
functionality, which turns debilitating, as opposed to disorders of
hypo-functionality, as is often assumed. We discuss how excessive
neuronal processing may render the world painfully intense when the
neocortex is affected and even aversive when the amygdala is
affected, leading to social and environmental withdrawal. Excessive
neuronal learning is also hypothesized to rapidly lock down the
individual into a small repertoire of secure behavioral routines that
are obsessively repeated. We further discuss the key autistic
neuropathologies and several of the main theories of autism and re-
interpret them in the light of the hypothesized Intense World
Syndrome.