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In order to advance fundamental and clinical neuroscience it is necessary to understand the relative contributions of large vessel and microvessel signals in human cortex BOLD fMRI responses. Line-scanning fMRI 1, 2, 3 achieves extremely high reso-lution across both cortical depth (250 lm) and time (100 ms), by sacrificing volume coverage and resolution along the cortical surface. This unprecedented spatiotemporal resolution can allow us to identify microvessel responses and to characterize the distribution of blood flow across cortical depth. Here we present preliminary results of a human line-scanning fMRI experiment investigating hemodynamic signals in human visual cortex. Two volunteers were scanned at 7T (Philips) with a 32 channel receive head coil (Nova Medical). Line scans were acquired with: line resolution= 250 lm, TR/TE= 103/12 ms, 2400 timepoints, flip angle= 16, array size= 720, line thick-ness= 2.5 mm, in-plane line width= 5 mm, fat suppression using SPIR. Two saturation pulses (5 ms pulse duration) were used to suppress the signal outside the line of interest. The phase-encoding in the direction perpendicular to the line was turned off 2. The line was positioned in right/left direction, crossing the visual cortex (Fig. 1). Data was acquired during intermittent bilateral visual stimulation in 4 runs. Visual stimuli were 8 Hz flickering gratings, presented for 750 ms with an exponential ISI distribution (mean of 2 s, plus a minimum of 2 s). Reconstruction was performed offline with MatLab and Gyrotools. Multiple coil data were combined weighting the signal with the temporal signal to noise …