Assessment and quantification of head motion in neuropsychiatric functional imaging research as applied to schizophrenia

Abstract

Differing degrees of head motion have long been recognized as a potential confound in functional neuroimaging studies comparing neuropsychiatric populations to healthy normal volunteers, and studies often cite excessive head motion as a possible reason for the different patterns of functional activation frequently observed between groups. We empirically tested the degree of head motion in 16 patients with chronic schizophrenia and 16, age- and education-matched controls during the acquisition of functional magnetic resonance imaging data. We examined the degree of motion across three different indices (total motion, relative motion, task-correlated motion) during a complex attentional task and the effect of entering the motion parameters as additional regressors in a general linear model analysis. Results indicate that individuals with schizophrenia did not exhibit more task-correlated or total motion compared with controls. Moreover, the residual error term from the general linear model analysis was similar for both groups of subjects. In conclusion, current results suggest that stable patients with schizophrenia are capable of controlling head motion compared with matched normal controls. However, a direct comparison of the motion parameters is an essential step for any quality assurance protocol to determine whether additional corrective techniques need to be implemented.

Urgency urinary incontinence and the interoceptive network: a functional magnetic resonance imaging study

“…Data for three UUI participants and three Controls were excluded secondary to acquisition issues or excessive head motion (3 times the inter-quartile range relative to their cohort based on frame-wise displacement). 19 A total of 53 UUI participants and 20 Controls were included in the final functional task analysis.…”

Developmental changes between ages 13 and 21 years in the extent and magnitude of the BOLD response during decision making

“…The degree of head motion during scanning was greater in the 13-year-olds compared with the two older age groups on the two most affected parameters (Mayer et al, 2007;Yoo et al, 2005), viz translation in the z direction (Tz; F (2, 63) = 5.40; p = .007) and rotation in the x direction (Rx; F (2, 63) = 6.77; p = .002). In order to control for the confounding effect of head motion we applied 3 corrections to our data.…”

Proactive response inhibition abnormalities in the sensorimotor cortex of patients with schizophrenia

“…Functional imaging maps were calculated with the Analysis of Functional NeuroImages (AFNI) software using standard preprocessing steps, including calculation of framewise displacement (FD). 26 Deconvolution was used to generate a single HRF for each trial type relative to baseline (visual fixation plus baseline gradient noise) for the first 22 s after stimulus onset. We calculated percent signal change (PSC) by summing β coefficients for images occurring 6-14 s after cue onset and dividing by the average model intercept.…”