hoffmanphantom {catsim}R Documentation

An example fMRI phantom

Description

A 128 x 128 activation map for a slice of an fMRI phantom and an anatomical reference.

Usage

data(hoffmanphantom)

Format

a 128 x 128 x 2 array with the first slice an activation map for an MRI phantom and the second an anatomical overlay. NA values are outside the surface. The activation map (hoffmanphantom[,,1]) is 1 if activated, 0 otherwise. The second layer (hoffmanphantom[,,2]) indicates the anatomical structure. Approximately 3.8 percent of the pixels are activated in this slice.

References

E. Hoffman, P. Cutler, W. Digby, and J. Mazziotta, “3-D phantom to simulate cerebral blood flow and metabolic images for PET,” Nuclear Science, IEEE Transactions on, vol. 37, pp. 616 – 620, 05 1990.

I. A. Almodóvar-Rivera and R. Maitra, “FAST adaptive smoothed thresholding for improved activation detection in low-signal fMRI,” IEEE Transactions on Medical Imaging, vol. 38, no. 12, pp. 2821–2828, 2019.

Examples

image(hoffmanphantom[, , 2], col = rev(gray(0:15 / 16))[1:4], axes = FALSE)
image(hoffmanphantom[, , 1],
  add = TRUE, zlim = c(0.01, 1),
  col = c("yellow", "maroon")
)

[Package catsim version 0.2.3 Index]