add a notebook for comparing cbmr and cbma on neurosynth

examples/02_meta-analyses/12_compare_cbmr_and_cbma.py

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+"""
+
+.. _metas_cbmr_vs_cbma:
+
+================================================================
+Compare coordinate-based meta-regression and meta-analysis methods
+================================================================
+
+A comparison between coordinate-based meta-regression (CBMR) and
+coordinate-based meta-analysis (CBMA) in NiMARE
+
+CBMR is a generative framework to approximate smooth activation intensity function and investigate
+the effect of study-level moderators (e.g., year of pubilication, sample size, subtype of stimuli).
+It allows flexible statistical inference for either spatial homogeneity tests or group comparison
+tests. Additionally, it's a computationally efficient approach with good statistical
+interpretability to model the locations of activation foci.
+
+This tutorial is intended to provide an intuitive comparison of CBMA and MKDA results on
+neurosynth dataset.
+
+For more detailed introduction to CBMR implementation in NiMARE, see the `CBMR tutoral
+<https://nimare.readthedocs.io/en/latest/auto_examples/02_meta-analyses/11_plot_cbmr.html>`_ and
+`documatation <https://nimare.readthedocs.io/en/latest/generated/nimare.meta.cbmr.html>`_.
+
+"""
+import os
+
+from nimare.extract import download_abstracts, fetch_neurosynth
+from nimare.io import convert_neurosynth_to_dataset
+from nimare.meta import models
+from nilearn.plotting import plot_stat_map
+
+###############################################################################
+# Download the Neurosynth Dataset
+# -----------------------------------------------------------------------------
+# Neurosynth is a large-scale functional magnetic resonance imaing (fMRI) database.
+# There are currently 507891 activations reported in 14371 studies in the Neurosynth
+# database, with interactive, downloadable meta-analyses of 1334 terms. There is also
+# a `platform <https://neurosynth.org/>`_ designed for automated synthesis of fMRI data.
+
+out_dir = os.path.abspath("../example_data/")
+os.makedirs(out_dir, exist_ok=True)
+
+files = fetch_neurosynth(
+    data_dir=out_dir,
+    version="7",
+    overwrite=False,
+    source="abstract",
+    vocab="terms",
+)
+# Note that the files are saved to a new folder within "out_dir" named "neurosynth".
+neurosynth_db = files[0]
+
+neurosynth_dset = convert_neurosynth_to_dataset(
+    coordinates_file=neurosynth_db["coordinates"],
+    metadata_file=neurosynth_db["metadata"],
+    annotations_files=neurosynth_db["features"],
+)
+neurosynth_dset.save(os.path.join(out_dir, "neurosynth_dataset.pkl.gz"))
+
+neurosynth_dset = download_abstracts(neurosynth_dset, "[email protected]")
+neurosynth_dset.save(os.path.join(out_dir, "neurosynth_dataset_with_abstracts.pkl.gz"))
+
+###############################################################################
+# For term-based meta-analyses, we split the whole Neurosynth dataset into two subsets,
+# one including all studies in the Neurosynth database whose abstracts include the term
+# at least once, the other including all the remaining studies. Here, we will conduct
+# meta-analyses based on the term "pain", and explore the spatial convergence between
+# pain studies and other fMRI studies.
+
+# extract study_id for pain dataset and non-pain dataset
+all_study_id = neurosynth_dset.annotations["id"]
+pain_study_id = neurosynth_dset.get_studies_by_label(labels=["terms_abstract_tfidf__pain"])
+non_pain_study_id = list(set(list(all_study_id)) - set(pain_study_id))  # 13855 studies
+# add an additional column for group
+neurosynth_dset.annotations.loc[all_study_id.isin(pain_study_id), "group"] = "pain"
+neurosynth_dset.annotations.loc[all_study_id.isin(non_pain_study_id), "group"] = "non_pain"
+
+###############################################################################
+# Estimation of group-specific spatial intensity functions
+# -----------------------------------------------------------------------------
+# Now we are going to run CBMR framework on the Neurosynth Dataset and estimate
+# spatial intensity functions for both pain studies and non-pain fMRI studies.
+
+from nimare.meta.cbmr import CBMREstimator
+cbmr = CBMREstimator(
+    group_categories="group",
+    moderators=None,
+    spline_spacing=10,  # a reasonable choice is 10 or 5, 100 is for speed
+    model=models.PoissonEstimator,
+    penalty=False,
+    lr=1e-1,
+    tol=1e-2,   # a reasonable choice is 1e-2, 1e3 is for speed
+    device="cpu",  # "cuda" if you have GPU
+)
+results = cbmr.fit(dataset=neurosynth_dset)
+
+###############################################################################
+# Now that we have fitted the model, we can plot the spatial intensity maps.
+
+plot_stat_map(
+    results.get_map("spatialIntensity_group-Pain"),
+    cut_coords=[0, 0, -8],
+    draw_cross=False,
+    cmap="RdBu_r",
+    title="Pain studies",
+    threshold=3e-4,
+    vmax=1e-3,
+)
+plot_stat_map(
+    results.get_map("spatialIntensity_group-Non_pain"),
+    cut_coords=[0, 0, -8],
+    draw_cross=False,
+    cmap="RdBu_r",
+    title="Non-pain fMRI studies",
+    threshold=3e-4,
+    vmax=1e-3,
+)
+
+###############################################################################
+# These two figures correspond to group-specific spatial intensity map of pain group
+# and non-pain group. Areas with stronger spatial intensity are highlighted.
+
+###############################################################################
+# Group-wise tests for spatial homogeneity
+# -----------------------------------------------------------------------------
+# For group-wise spatial homogeneity test, we generate contrast matrix *t_con_groups*
+# by specifying the group names in *create_contrast* function, and generate group-wise
+# p-value and z-score maps for spatial homogeneity tests.
+from nimare.meta.cbmr import CBMRInference
+
+inference = CBMRInference(device="cpu")
+inference.fit(result=results)
+t_con_groups = inference.create_contrast(
+    ["Pain", "Non_pain"], source="groups"
+)
+contrast_result = inference.transform(t_con_groups=t_con_groups)
+
+###############################################################################
+
+# generate z-score maps for group-wise spatial homogeneity test.
+plot_stat_map(
+    contrast_result.get_map("z_group-Pain"),
+    cut_coords=[0, 0, -8],
+    draw_cross=False,
+    cmap="RdBu_r",
+    title="Z-score map for spatial homogeneity test on pain studies",
+    threshold=20,
+    vmax=30,
+)
+
+plot_stat_map(
+    contrast_result.get_map("z_group-Non_pain"),
+    cut_coords=[0, 0, -8],
+    draw_cross=False,
+    cmap="RdBu_r",
+    title="Z-score map for spatial homogeneity test on non-pain fMRI studies",
+    threshold=20,
+    vmax=30,
+)
+
+###############################################################################
+# Group comparison test between pain studies and non-pain fMRI studies
+# -----------------------------------------------------------------------------
+# CBMR framework also allows flexible statistical inference for group comparison
+# between any two or more groups. For example, it's straightforward to generate
+# contrast matrix *t_con_groups* by specifying *contrast_name* as "group1-group2".
+
+inference = CBMRInference(device="cpu")
+inference.fit(result=results)
+t_con_groups = inference.create_contrast(
+    ["Pain-Non_pain"], source="groups"
+)
+contrast_result = inference.transform(t_con_groups=t_con_groups)
+
+###############################################################################
+
+# generate z-statistics maps for each group
+plot_stat_map(
+    contrast_result.get_map("z_group-Pain-Non_pain"),
+    cut_coords=[0, 0, 0],
+    draw_cross=False,
+    cmap="RdBu_r",
+    title="Spatial convergence between pain studies and Non-pain fMRI studies",
+    threshold=6,
+    vmax=20,
+)
+
+###############################################################################
+# This figure (displayed as z-statistics map) shows CBMR group comparison test
+# of spatial intensity between pain studies and non-pain studies in Neurosynth.
+# The null hypothesis assumes spatial intensity estimations of two groups are equal
+# at voxel level, $H_0: \mu_{1j}=\mu_{2j}, j=1,\cdots,N$, where $N$ is number of
+# voxels within brain mask, $j$ is the index of voxel. Areas with significant p-vaules
+# (siginificant difference in spatial intensity estimation between two groups) are
+# highlighted. We found that estimated activation level are significantly different
+# in ... between pain group and non-pain group.
+
+###############################################################################
+# Run MKDA on Neurosynth dataset
+# -----------------------------------------------------------------------------
+# For the purpose of justifying the validity of CBMR framework, we compare the estimated
+# spatial covergence of activation regions between pain studies and non-pain fMRI studies
+# with MKDA.
+
+from nimare.meta.cbma.mkda import MKDAChi2
+
+pain_dset = neurosynth_dset.slice(ids=pain_study_id)
+non_pain_dset = neurosynth_dset.slice(ids=pain_study_id)
+
+meta = MKDAChi2()
+results = meta.fit(pain_dset, non_pain_dset)
+
+plot_stat_map(
+    results.get_map("z_desc-consistency"),
+    cut_coords=[0, 0, -8],
+    draw_cross=False,
+    cmap="RdBu_r",
+    title="MKDA Chi-square analysis between pain studies and non-pain studies",
+    threshold=5,
+)
+
+###############################################################################
+# This figure (displayed as z-statistics map) shows MKDA spatial covergence of
+# activation between pain studies and non-pain fMRI studies. We found the results are
+# very consistent with CBMR approach, with higher specificity but lower sensitivity.