here is the astract i wrote for a SURP program last summer
Thalamus volume and glucose metabolism in autism spectrum disorder
patients.
Abstract
The flow of sensory information to the cortex is controlled by the
thalamus. Patients with autism spectrum disorders have known sensory
impairments suggesting thalamic abnormalities. However, postmortem
studies with autism have not found any abnormalities in thalamus. In
this
study, positron emission tomography (PET) and magnetic resonance imaging
(MRI) scans were used to measure the relative glucose metabolic rate
(rGMR) and assess the volume of the thalamus in 20 patients with
high-functioning autism (N = 9) or Asperger's disorder (N=11) and 23
age-
and sex-matched controls. Subjects performed the California Verbal
Learning Test (CVLT) during the PET uptake of
[(18)F]-fluorodeoxyglucose.
The thalamus was outlined on contiguous axial MRI slices and then
co-registered to the PET scan. We analyzed the relative volume and the
relative metabolism of the thalamus using a Group (Normal Controls,
Autism, Asperger's disorder) by Hemisphere (Left, Right)
repeated-measures
ANOVA. There were no group differences in the volume of the thalamus.
However, we found that patients with Autism had significantly lower in
rGMR compared with normal controls and Asperger's disorder patients
(F=3.95, df=2, 40, p=0.027). Our results replicate two previous studies
which showed thalamic functional changes in autism patients. In the
future, we plan to correlate rGMR with neuropsychological clinical scores.