ALE meta-analyses of voxel-based morphometry studies: Parameter validation via large-scale simulations

NeuroImage, vol. 281, pp. 120383

Abstract

Activation likelihood estimation (ALE) meta-analysis has been applied to structural neuroimaging data since long, but up to now, any systematic assessment of the algorithm's behavior, power and sensitivity has been based on simulations using functional neuroimaging databases as their foundation. Here, we aimed to determine whether the guidelines offered by previous evaluations can be generalized to ALE meta-analyses of voxel-based morphometry (VBM) studies. We ran 365000 distinct ALE analyses filled with simulated experiments, randomly sampling parameters from BrainMap's VBM experiment database. We then examined the algorithm's sensitivity, its susceptibility to spurious convergence, and its susceptibility to excessive contributions by individual experiments. In general, the performance of the ALE algorithm was highly comparable between imaging modalities, with the algorithm's sensitivity and specificity reaching similar levels with structural data as previously observed with functional data. Because of the lower number of foci reported and the higher number of participants usually included in structural experiments, individual studies had, on average, a higher impact towards significant clusters. To prevent significant clusters from being driven by single experiments, we recommend that researchers include at least 23 experiments in a VBM ALE dataset, instead of the previously recommended minimum of n = 17. While these recommendations do not constitute hard borders, running ALE analyses on smaller datasets would require special diligence in assessing and reporting the contributions of experiments to individual clusters.

Authors 5

1. Lennart Frahm corresponding Aachen Department of Psychiatry, Psychotherapy and Psychosomatics School of Medicine

   RWTH Aachen University · Forschungszentrum Jülich

   Affiliation as printed

   Department of Psychiatry, Psychotherapy and Psychosomatics, School of Medicine, RWTH Aachen University, Aachen, Germany; Institute of Neuroscience and Medicine (INM7: Brain and Behaviour), Research Centre Jülich, Jülich, Germany. Electronic address: l.frahm@fz-juelich.de

   Department of Psychiatry, Psychotherapy and Psychosomatics, School of Medicine, RWTH Aachen University, Aachen, Germany

   Institute of Neuroscience and Medicine (INM7: Brain and Behaviour), Research Centre Jülich, Jülich, Germany

2. Theodore Daniel Satterthwaite

   University of Pennsylvania

   Affiliation as printed

   Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA; Penn Lifespan Informatics and Neuroimaging Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA

   Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA

   Penn Lifespan Informatics and Neuroimaging Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA

3. Peter T. Fox

   The University of Texas at San Antonio Health Science Center

   Affiliation as printed

   Research Imaging Institute, University of Texas Health Science Center, San Antonio, USA; Departments of Radiology, Neurology, Psychiatry and Behavioral Sciences, and Physiology, University of Texas Health Science Center, San Antonio, USA

   Departments of Radiology, Neurology, Psychiatry and Behavioral Sciences, and Physiology, University of Texas Health Science Center, San Antonio, USA

   Research Imaging Institute, University of Texas Health Science Center, San Antonio, USA

4. Robert Langner

   Forschungszentrum Jülich · Heinrich Heine University Düsseldorf

   Affiliation as printed

   Institute of Neuroscience and Medicine (INM7: Brain and Behaviour), Research Centre Jülich, Jülich, Germany; Institute of Systems Neuroscience, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany

   Institute of Neuroscience and Medicine (INM7: Brain and Behaviour), Research Centre Jülich, Jülich, Germany

   Institute of Systems Neuroscience, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany

5. Simon Bodo Eickhoff

   Forschungszentrum Jülich · Heinrich Heine University Düsseldorf

   Affiliation as printed

   Institute of Neuroscience and Medicine (INM7: Brain and Behaviour), Research Centre Jülich, Jülich, Germany; Institute of Systems Neuroscience, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany

   Institute of Neuroscience and Medicine (INM7: Brain and Behaviour), Research Centre Jülich, Jülich, Germany

   Institute of Systems Neuroscience, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany