[Neuroimaging findings in autism: a brief review].
OBJECTIVE
Many structural and functional neuroimaging studies have investigated the neuroanatomical changes and possible pathophysiological pathways in autism. In this review the objective was to assess, with an integrative perspective, recent neuroimaging studies that have contributed to the explanation of the possible pathophysiological pathways in autism.


METHODS
Relevant attainable studies published between 1997 and 2007 were included in this retrospective literature review. The PubMed search engine and the keywords, autism, autistic spectrum disorders, neuroimaging, computerized tomography, magnetic resonance imaging, functional magnetic resonance imaging, magnetic resonance spectroscopy, positron emission tomography, single photon emission computed tomography, and diffusion tensor imaging were used.


RESULTS
Structural neuroimaging studies reported an increase in total cerebral volume, both in grey and white matter, mostly in the frontal, temporal and parietal lobes. These global volumetric changes are suggested to indicate a diffuse disturbance in neural networks during early development. In functional neuroimaging studies, activation abnormalities were observed in the temporal lobes and amygdala, which are involved in language and social cognition. An increase in visual activity cortex was also reported.


CONCLUSIONS
Clinical observations and results from neuroimaging studies were gathered to hypothize and explain the pathophysiology of autism. Yet, it is still very early to conclude with certainty the neurobiological process responsible for autism.
Ulay
Halime Tuna
HT
Asis., Hacettepe U Cocuk ve Ergen Ruh Sağliği ve Hastaliklari AD., Ankara. tunacak@yahoo.com
Ertuğrul
Aygün
A
D000679:Amygdala / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D001321:Autistic Disorder / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D001931:Brain Mapping; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D010296:Parietal Lobe / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D013702:Temporal Lobe / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D014055:Tomography, Emission-Computed