² Color Opacity lets you select the opacity of colored voxels (those
that are above the
threshold)
åOpacity of overlaid
voxels is different from the opacity it would have from the underlay dataset at
that location
åUsually want this to
be high (0.5 or above)
åTow special values
on this menu:
Ø Underlay means that the colored voxelÕs opacity will be determined by the opacity
that it would have from the underlay image
Ø ShowThru means
that colored voxels show through underlay voxels (the Ôglass brainÕ
effect), no matter how opaque the underlay is
¥Takes some practice to become accustomed to this type of
image
¥But can be a very useful way to see lots of activation
at once: