PowerPoint Presentation - Time Series Analysis in AFNI

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3dDeconvolve with Free Timing

• The fixed-TR stick function approach doesn’t fit with arbitrary timing of stimuli

H When subject actions/reactions are self-initiated, timing of activations cannot be controlled

• If you want to do deconvolution, then must adopt a different basis function expansion approach

H One that has a finite number of parameters but also allows for calculation of h(t ) at any arbitrary point in time

• Simplest set of such functions are closely related to stick functions: tent functions

time

t=0

t=TR

t=2×TR

t=3×TR

t=4×TR

t=5×TR