MKDA outputs over the Neurosynth corpus

Overview

CANlab Multilevel Kernel Density Analysis (MKDA) intermediate outputs computed over the Neurosynth coordinate corpus. MKDA convolves each study's reported peak coordinates with an indicator kernel and aggregates across studies to obtain a voxel-wise activation-proportion map (and inference structures for permutation testing). The folder holds the CANlab MKDA SETUP / MC_Info MAT-files plus a single summary Activation_proportion image; these are produced by Neurosynth_maps/scripts/ns_matlab_prep_MKDA.m as part of the Neurosynth build pipeline and are reused by other CANlab analyses (co-activation, seed maps, etc.).

Primary reference

Derived from the Neurosynth coordinate database as part of the CANlab build pipeline; the MKDA method itself is:

• Wager, T. D., Lindquist, M., & Kaplan, L. (2007). Meta-analysis of functional neuroimaging data: Current and future directions. Social Cognitive and Affective Neuroscience, 2(2), 150–158. doi:10.1093/scan/nsm015
• Wager, T. D., Lindquist, M. A., Nichols, T. E., Kober, H., & Van Snellenberg, J. X. (2009). Evaluating the consistency and specificity of neuroimaging data using meta-analysis. NeuroImage, 45(1, Suppl.), S210–S221. doi:10.1016/j.neuroimage.2008.10.061

For the underlying corpus see Yarkoni et al. 2011 Nat Methods (linked from ../2016_Neurosynth_100_topics/contents_description.md).

Key images

Cortical surface	Axial montage

The MKDA-summary Activation_proportion map — the voxel-wise proportion of Neurosynth studies reporting activation at each location. The matching isosurface is in png_images/Neurosynth_MKDA_Activation_proportion_isosurface.png; rendered by visualize_contents.m.

How to load

Not in load_image_set. Load the summary image directly:

ap = fmri_data(which('Activation_proportion.img'));

The .mat files are CANlab MKDA structures and are intended to be consumed by CANlab MKDA helpers (Meta_Activation_FWE, Meta_Setup, permutation-test runners). For example:

load(which('SETUP.mat'));      % SETUP struct
load(which('MC_Info.mat'));    % Monte-Carlo permutation info

File inventory

File	Type	What it is
Activation_proportion.img / .hdr	Analyze	Voxel-wise proportion of Neurosynth studies reporting activation.
SETUP.mat	MAT	CANlab MKDA SETUP structure (study list, kernels, contrasts).
MC_Info.mat	MAT	Monte-Carlo / permutation info used for FWE inference.
visualize_contents.m	MATLAB	Renders the activation-proportion map to png_images/.

Citations

• Wager TD, Lindquist M, Kaplan L (2007). Meta-analysis of functional neuroimaging data. SCAN 2:150–158. doi:10.1093/scan/nsm015
• Wager TD, Lindquist MA, Nichols TE, Kober H, Van Snellenberg JX (2009). Evaluating the consistency and specificity of neuroimaging data using meta-analysis. NeuroImage 45:S210–S221. doi:10.1016/j.neuroimage.2008.10.061
• Yarkoni T, Poldrack RA, Nichols TE, Van Essen DC, Wager TD (2011). Large-scale automated synthesis of human functional neuroimaging data. Nat Methods 8:665–670. doi:10.1038/nmeth.1635