Influence of sample size and analytic approach on stability and interpretation of brain-behavior correlations in task-related fMRI data.

ABSTRACT: Limited statistical power due to small sample sizes is a problem in fMRI research. Most of the work to date has examined the impact of sample size on task-related activation, with less attention paid to the influence of sample size on brain-behavior correlations, especially in actual experimental fMRI data. We addressed this issue using two large data sets (a working memory task, N = 171, and a relational processing task, N = 865) and both univariate and multivariate approaches to voxel-wise correlations. We created subsamples of different sizes and calculated correlations between task-related activity at each voxel and task performance. Across both data sets the magnitude of the brain-behavior correlations decreased and similarity across spatial maps increased with larger sample sizes. Th

SUBMITTER: Grady CL 

PROVIDER: S-EPMC7721240 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature