M. Senda et al., INFLUENCE OF ANOVA DESIGN AND ANATOMICAL STANDARDIZATION ON STATISTICAL MAPPING FOR PET ACTIVATION, NeuroImage (Orlando, Fla. Print), 8(3), 1998, pp. 283-301
Citations number
53
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Neurosciences,"Radiology,Nuclear Medicine & Medical Imaging
We have created images of z value, error, and variation components for
a PET activation study using various ANOVA designs and anatomical sta
ndardization methods. Data were acquired in four PET centers. In each
center, CBF was measured on six normal male subjects under resting and
covert verb generation, three times for each. The images were anatomi
cally; standardized with LINEAR transformation, SPM (Ver. 95), HBA (Ka
rolinska/Tohoku), or MICHIGAN (Minoshima). ANOVA was performed pixel b
y pixel to compute t (and z) for the task main effect (Verb vs Rest) i
n four different designs: (i) two way (subject and task) (2W), (ii) tw
o-way with interaction (2WI), (iii) subject considered a random factor
(2WI-MX), and (iv) three-way (subject, task, and replication) (3W). A
large area extending from the Broca to the left premotor cortex was a
ctivated. The localization of the highest peak depended both on the an
atomical standardization and on the ANOVA design, the variation rangin
g 3-4 cm. Smoothing reduced the variation while erasing possible subfo
ci. The z images of 2W, 2WI, and 3W looked alike, whereas 2WI-MX prese
nted lower peak z values. SPM tended to present higher z values than t
he other methods. The error was high in the gray and low in the white
matter. The root mean square for the subject effect was high on the bo
rder of gray matter especially in LINEAR and HBA, revealing intersubje
ct mismatch in the gray matter distribution. The root mean square for
the subject-by-task interaction effect revealed individual variation i
n activation. (C) 1998 Academic Press.