In a follow-up study of 14 more toluene abusers, detailed
neuropsychological testing and magnetic resonance
imaging (MRI) scans showed that neuropsychological deficits
in patients with toluene-induced white matter damage
correlated with the patient’s neuroimaging findings
(22). After blinded ratings of both neuropsychological
testing and MRI scans were independently conducted, the
level of cognitive impairment, often sufficient to be
called dementia, was found to correlate directly with the
severity of leukoencephalopathy detected on MRI (22).
This study was the first to demonstrate that toluene abusers
develop a dementia syndrome that directly parallels
the degree of white matter damage as demonstrated by
neuroimaging (22)