PowerPoint Presentation - Using AFNI Interactively

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• First: Block-trial FMRI data

H “Activation” occurs over a sustained period of time (say, 10 s or longer), usually from more than one stimulation event, in rapid succession

H BOLD (hemodynamic) response accumulates from multiple close activations and is large

H BOLD response is often visible in time series

• Next 4 slides: same brain voxel in 9 imaging runs

H black curve (noisy) = data

H red curve (above data) = ideal model response

H blue curve (within data) = model fitted to data

H somatosensory task (finger being rubbed)

Some Sample FMRI Data Time Series