Alterations in the hemodynamic response function in cognitively impaired HIV/AIDS subjects.
Functional magnetic resonance imaging (fMRI) has revealed much about altered CNS function in HIV/AIDS. In this study, we compared the blood oxygen level dependent hemodynamic response function (BOLD HRF) signal in HIV/AIDS and control subjects as a necessary pre-condition for fMRI studies of higher level cognitive function. Using event-related fMRI, subjects performed a simple sensory-motor activity allowing the measurement of the BOLD HRF in the precentral gyrus. There were no significant differences in the HRF when viewed as a function of age, hemisphere, or HIV serostatus. However, significant results were found after dividing the subjects by NIMH impairment classifications. There were 16 control subjects, 19 Normal/Asymptomatic Neuropsychological Impairment (ANI), and 11 Minor Neurocognitive Disorder (MNCD)/HIV-Associated Dementia (HAD) subjects. The HRF of MNCD/HAD subjects did not return to baseline after 16s, suggesting subtle alterations in neuronal function, which may affect event-related fMRI studies.
Juengst
Shannon B
SB
Department of Psychiatry, University of Pittsburgh School of Medicine, United States. juengstsb@upmc.edu <juengstsb@upmc.edu>
Aizenstein
Howard J
HJ
Figurski
Jennifer
J
Lopez
Oscar L
OL
Becker
James T
JT
D015526:AIDS Dementia Complex / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology; D000328:Adult; D000375:Aging; D001921:Brain / Q000503:physiopathology* / Q000821:virology; D018791:CD4 Lymphocyte Count; D002560:Cerebrovascular Circulation / Q000502:physiology; D003072:Cognition Disorders / Q000175:diagnosis / Q000503:physiopathology* / Q000821:virology; D004185:Disability Evaluation; D005260:Female; D006679:HIV Seropositivity / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests