Peter Herman1, Robert N. S. Sachdev2, Basavaraju G. Sanganahalli1, Hal Blumenfeld2, 3, David A. McCormick2, Fahmeed Hyder1, 4
1Department of Diagnostic Radiology, Yale University, New Haven, CT, United States; 2Department of Neurobiology, Yale University, New Haven, CT, United States; 3Department of Neurology, Yale University, New Haven, CT, United States; 4Department of Biomedical Engineering, Yale UNiversity, New Haven, CT, United States
A long-standing hypothesis is that tasks or stimuli that evoke neural activity also trigger cerebral blood flow (CBF). Here we examined whether spontaneously occurring cortical fluctuations triggered changes in local blood flow in head-fixed awake and anesthetized rodents. While the linear correlations were rarely significant, using a convolution model of neurovascular coupling we found non-linear correlation between the neural and hemodynamic signals. The calculated transfer functions were significantly different in awake and anesthetized states. In particular the intensity of neurovascular signals decreases with deeper anesthesia and, the response time of the neurovascular coupling slows down.