estimate_hrf: Estimate hemodynamic response function (HRF) using...

In bbuchsbaum/fmrireg: R package for the anlysis of fmri data

Estimate hemodynamic response function (HRF) using Generalized Additive Models (GAMs)

Description

This function estimates the HRF using GAMs from the mgcv package. The HRF can be estimated with or without fixed effects.

Usage

estimate_hrf(
  form,
  fixed = NULL,
  block,
  dataset,
  bs = c("tp", "ts", "cr", "ps"),
  rsam = seq(0, 20, by = 1),
  basemod = NULL,
  k = 8,
  fx = TRUE
)

Arguments

form	A formula specifying the event model for the conditions of interest
fixed	A formula specifying the fixed regressors that model constant effects (i.e., non-varying over trials); default is NULL
block	A formula specifying the block factor
dataset	An object representing the fMRI dataset
bs	Basis function for the smooth term in the GAM; one of "tp" (default), "ts", "cr", or "ps"
rsam	A sequence of time points at which the HRF is estimated (default: seq(0, 20, by = 1))
basemod	A baseline_model instance to regress out of data before HRF estimation (default: NULL)
k	the dimension of the basis, default is 8
fx	indicates whether the term is a fixed d.f. regression spline (TRUE) or a penalized regression spline (FALSE); default is TRUE.

Value

A matrix with the estimated HRF values for each voxel

See Also

baseline_model, event_model, design_matrix

Examples

# To be added

bbuchsbaum/fmrireg documentation built on March 1, 2025, 11:20 a.m.