Neural Source of Laminar fMRI Responses Examined with Temporal Frequency Visual Stimuli

Cecil Chern-Chyi Yen¹, Hiro Fukuda², Seong-Gi Kim²

Neuroscientists have been interested in cortical laminar neural response for decades. If hemodynamic responses are sensitive to laminar neural activity, then high resolution fMRI may provide a non-invasive way to probe these activity. To investigate this issue, we intentionally modulated layer-dependent changes in neural activity during fMRI studies by manipulating the temporal characteristic of the visual stimuli. All laminar response of BOLD or CBV fRMI behaved similarly, even though spiking activity was reported to have different response in lower cortical layer. Our result suggests that it is currently very difficult for hemodynamic-based fMRI to differentiate layer-specific neural activity.