ALE meta‐analysis: Controlling the false discovery rate and performing statistical contrasts

Abstract

Activation likelihood estimation (ALE) has greatly advanced voxel-based meta-analysis research in the field of functional neuroimaging. We present two improvements to the ALE method. First, we evaluate the feasibility of two techniques for correcting for multiple comparisons: the single threshold test and a procedure that controls the false discovery rate (FDR). To test these techniques, foci from four different topics within the literature were analyzed: overt speech in stuttering subjects, the color-word Stroop task, picture-naming tasks, and painful stimulation. In addition, the performance of each thresholding method was tested on randomly generated foci. We found that the FDR method more effectively controls the rate of false positives in meta-analyses of small or large numbers of foci. Second, we propose a technique for making statistical comparisons of ALE meta-analyses and investigate its efficacy on different groups of foci divided by task or response type and random groups of similarly obtained foci. We then give an example of how comparisons of this sort may lead to advanced designs in future meta-analytic research.

Beyond hypofrontality: A quantitative meta‐analysis of functional neuroimaging studies of working memory in schizophrenia

“…This combined approach identified 21 potential articles. As primary source data must be reported in standard stereotactic coordinates (either Talairach or MNI space) to be used in voxel-level quantitative meta-analyses [Laird et al, 2005a;Turkeltaub et al, 2002], only 17 articles could be included in the review. Of these articles, only those that reported coordinates from patients with schizophrenia alone (n ϭ 7) or coordinates from patient-control contrasts were included (n ϭ 6; total n ϭ 12; see Table I).…”

“…Activation likelihood estimation (ALE) is a relatively new method of quantitative meta-analysis of functional neuroimaging data developed by Turkeltaub et al [2002] and significantly expanded by Laird et al [2005a]. ALE is a voxel-based method for finding concordance within a neuroimaging literature that does not rely upon author-assigned anatomical labels [Laird et al, 2005b].…”

“…As part of this special issue on quantitative meta-analysis for functional neuroimaging experiments, the current review utilizes voxel-based methods to consolidate imaging studies reported in Talairach coordinates to provide insights into the consistency of activation foci across experiments [Laird et al, 2005a]. Although prefrontal dysregulation in patients with schizophrenia was observed initially with the Wisconsin Card-Sorting Task [Weinberger et al, 1986], we restrict our review to experiments employing the n-back paradigm as it has been administered in a standard way across studies and results tend to be reported in a more contemporary framework (e.g., Talairach coordinates).…”

Lost in localization: The need for a universal coordinate database

“…It should also be possible to conduct searches for sets of coordinates, so that it is possible to search for networks (i.e., find papers that report activations within a set of locations). In addition, we consider it important that quantitative meta-analyses (Chein et al, 2002;Laird et al, 2005a;Turkeltaub et al, 2002;Wager & Smith, 2003) be included in the database and it be possible to restrict searches to these types of papers. This would allow for the identification of relevant papers on a meta-level.…”

A meta‐analysis of functional magnetic resonance imaging studies of eye movements and visual word reading

“…First, we used the coordinate database (Fox & Lancaster, 2002; Fox et al., 2005; Laird et al., 2005) in Brainmap Sleuth (http://brainmap.org/sleuth/index.html; RRID:SCR_002555) because it contains neuroimaging coordinates classified as saccade and word reading tasks. The terms “[Image Modality = fMRI] AND [Paradigm = Saccade]” were entered to search for studies of eye movements; the terms “[Image Modality = fMRI] AND [Behavioral Domain = Cognition.Language‐Orthography]” were entered to search for studies of word reading.…”