Reliability of an fMRI paradigm for emotional processing in a multisite longitudinal study

Abstract

Multisite neuroimaging studies can facilitate the investigation of brain-related changes in many contexts, including patient groups that are relatively rare in the general population. Though multisite studies have characterized the reliability of brain activation during working memory and motor functional magnetic resonance imaging tasks, emotion processing tasks, pertinent to many clinical populations, remain less explored. A traveling participants study was conducted with eight healthy volunteers scanned twice on consecutive days at each of the eight North American Longitudinal Prodrome Study sites. Tests derived from generalizability theory showed excellent reliability in the amygdala false(Eρ2=0.82false), inferior frontal gyrus false(normalIFG;Eρ2=0.83false), anterior cingulate cortex false(normalACC;0.2emEρ2=0.76false), insula false(Eρ2=0.85false), and fusiform gyrus false(Eρ2=0.91false) for maximum activation and fair to excellent reliability in the amygdala false(Eρ2=0.44false), IFG false(Eρ2=0.48false), ACC false(Eρ2=0.55false), insula false(Eρ2=0.42false), and fusiform gyrus false(Eρ2=0.83false) for mean activation across sites and test days. For the amygdala, habituation false(Eρ2=0.71false) was more stable than mean activation. In a second investigation, data from 111 healthy individuals across sites were aggregated in a voxelwise, quantitative meta-analysis. When compared with a mixed effects model controlling for site, both approaches identified robust activation in regions consistent with expected results based on prior single-site research. Overall, regions central to emotion processing showed strong reliability in the traveling participants study and robust activation in the aggregation study. These results support the reliability of blood oxygen level-dependent signal in emotion processing areas across different sites and scanners and may inform future efforts to increase efficiency and enhance knowledge of rare conditions in the population through multisite neuroimaging paradigms.

Reliability of an fMRI paradigm for emotional processing in a multisite longitudinal study: Clarification and implications for statistical power

“…As shown in Figure 1, when accounting for differential reliability in right fusiform gyrus and right amygdala, although higher levels of power are achieved with smaller sample sizes in the single-site compared with multisite context, multisite studies achieve acceptable levels of power (0.8) with moderate to large effect sizes (ES 0.5) beginning at sample sizes of 85 subjects for the right fusiform gyrus and 125 subjects for right amygdala. These results accord well with the results reported in our original study analyzing single-session scans from 111 healthy subjects, each drawn from one of the eight scanning sites, which observed robust activation in key emotion processing nodes (e.g., amygdala, inferior frontal gyrus, anterior cingulate cortex, fusiform gyrus) whether using image-based-meta-analysis or mixed effects modeling with site as a covariate (Gee et al, 2015), suggesting task-related effect sizes of 0.5 or higher for maximum activation in these regions.…”

“…We wish to make explicit that in applying generalizability theory, we estimated reliability by calculating generalizability and dependability coefficients for a study design corresponding to the design of the full traveling subject study, thus reflecting the reliability in relative and absolute measurement, respectively, that one can expect when every subject is scanned twice on each of eight different scanners. The corresponding generalizability and dependability coefficients (shown in figure 4 and cited in the abstract in Gee et al, 2015) ranged from 0.0 to 0.9 for maximum activation across multiple task contrasts and regions of interest, but were generally at or above 0.5, as would be expected when each subject's measurement is based on the aggregation of 16 scan sessions. Thus, the coefficients reported apply to the reliability of the measures from the reliability study itself, that is, for task-induced brain activations resulting from analysis of the eight traveling subjects' fMRI data considered in aggregate across their 16 scan sessions.…”

“…Here we report generalizability and dependability coefficients that represent the reliability one can expect for a multisite study, in which a given subject is scanned once on a scanner drawn randomly from the pool of available scanners (i.e., analogous to the more typical multisite study design). We also characterize the implications of a multisite versus single-site study design for statistical power, including Figure 1 that shows sample size requirements to detect activation in two key nodes of the emotion processing circuitry given observed differences in reliability of measurement between single-site and multisite designs.We take this opportunity to clarify the meaning of the statistics reported in our study examining reliability of fMRI measures of brain activation during an emotion processing task (Gee et al, 2015) and to consider their implications for statistical power in single-site versus multisite designs.In our report, we used a variance components framework and an application of generalizability theory (Shavelson & Webb, 1991) to probe the robustness of such measures in a multisite context. Given the design of our study, in which eight human subjects were scanned twice on successive days at each of eight sites, the proportion of variance due to person from the variance components analysis (shown in figure 3 in Gee et al, 2015) represents the reliability one can expect in a typical multisite study where subject measurements are based on singlesession fMRI data, each acquired on different scanners depending on the site where the subject was recruited.…”

Literature and Empathy in Nursing Students

“…Because fiction literature allows nursing students (through guided imagery and other literary tools), the group with the additional course comprehended empathy and embraced it better than the control group. flow in various regions central to emotion processing during specific task conditions (Gee, McEwen, Forsyth, Haut, Bearden, Addington, and Cannon, 2015). A study performed by Gee et al (2015) has confirmed the reliability in imaging signals of activation of emotion processing regions in the brain when stimulated by relevant tasks.…”

“…flow in various regions central to emotion processing during specific task conditions (Gee, McEwen, Forsyth, Haut, Bearden, Addington, and Cannon, 2015). A study performed by Gee et al (2015) has confirmed the reliability in imaging signals of activation of emotion processing regions in the brain when stimulated by relevant tasks. Study/test results are only viable when proven in research using reliable sources and equipment.…”