canonicalHRF: Double-gamma Haemodynamic reponse function

In neuRosim: Simulate fMRI Data

Double-gamma Haemodynamic reponse function

Description

Specifies a double-gamma variate haemodynamic response function for the given time vector and parameters.

Usage

  canonicalHRF(x, param = NULL, verbose = TRUE)

Arguments

x	Time vector in seconds.
param	List of parameters of the haemodynamic response function. The list should contain the following: a1 Delay of response relative to onset (default: 6) a2 Delay of undershoot relative to onset (default:12) b1 Dispersion of response (default:0.9) b2 Dispersion of undershoot (default:0.9) c Scale of undershoot (default:0.35)
verbose	If TRUE, warnings are displayed.

Value

Vector representing the values of the function for the given time vector and parameters.

Author(s)

M. Welvaert

References

[1] Friston, KJ, Fletcher, P, Josephs, O, Holmes, AP, Rugg, MD and Turner, R (1998). Event-related fMRI: Characterising differential responses. NeuroImage, 7, 30-40.

[2] Glover, GH (1999). Deconvolution of impulse response in event-related BOLD fMRI. NeuroImage, 9, 416-429.

See Also

gammaHRF, balloon

Examples

t <- 1:100
out <- canonicalHRF(t, verbose=FALSE)

neuRosim documentation built on Oct. 18, 2023, 5:09 p.m.