Esempio n. 1
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def test_dics_connectivity():
    """ Test dics_connectivity function"""
    source_vertno1 = 146374  # Somewhere on the frontal lobe
    source_vertno2 = 33830
    # Load restricted forwards
    fwd, fwd_fixed = _load_restricted_forward(source_vertno1, source_vertno2)
    csd = _simulate_data(fwd_fixed, source_vertno1, source_vertno2)
    # Take subset of pairs to make calculations faster
    pairs = all_to_all_connectivity_pairs(fwd, 0.05)

    # CSD not averaged
    with pytest.raises(ValueError):
        con = dics_connectivity(pairs, fwd, csd)
    csd = csd.mean()
    # Fixed forward
    with pytest.raises(ValueError):
        dics_connectivity(pairs, fwd_fixed, csd)
    # Incorrect pairs
    with pytest.raises(ValueError):
        dics_connectivity([[0, 1, 3], [2, 4]], fwd, csd)

    con = dics_connectivity(pairs, fwd, csd, reg=1)
    max_ind = np.argmax(con.data)
    vertices = np.concatenate(con.vertices)
    assert len(con.data) == len(pairs[0])
    assert con.n_sources == fwd['nsource']
    assert vertices[pairs[0][max_ind]] == source_vertno1
    assert vertices[pairs[1][max_ind]] == source_vertno2
    # Check result is the same with tangential
    fwd_tan = forward_to_tangential(fwd)
    con2 = dics_connectivity(pairs, fwd_tan, csd, reg=1)
    assert_array_equal(con2.data, con.data)
Esempio n. 2
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def test_all_to_all_connectivity_pairs():
    fwd = _load_forward()
    # Test using forward
    total_vertices = len(fwd['source_rr'])
    # All should pass
    pairs = all_to_all_connectivity_pairs(fwd, min_dist=0)
    assert max(pairs[0].max(), pairs[1].max()) == total_vertices - 1
    # None should pass
    pairs = all_to_all_connectivity_pairs(fwd, min_dist=1)
    assert pairs[0].size == 0
    assert pairs[1].size == 0

    # Test using SourceSpaces
    # All should pass
    pairs = all_to_all_connectivity_pairs(fwd['src'], min_dist=0)
    assert max(pairs[0].max(), pairs[1].max()) == total_vertices - 1
    # None should pass
    pairs = all_to_all_connectivity_pairs(fwd['src'], min_dist=1)
    assert pairs[0].size == 0
    assert pairs[1].size == 0

    # Incorrect input
    with pytest.raises(ValueError):
        all_to_all_connectivity_pairs([], min_dist=1)
Esempio n. 3
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    # Save a visualization of the restricted forward operator to the subject's
    # HTML report
    with mne.open_report(fname.report(subject=subject)) as report:
        fig = mne.viz.plot_alignment(fwd['info'],
                                     trans=fname.trans(subject=subject),
                                     src=fwd_r['src'],
                                     meg='sensors',
                                     surfaces='white')
        fig.scene.background = (1, 1, 1)  # white
        g = fig.children[-1].children[0].children[0].glyph.glyph
        g.scale_factor = 0.008
        mlab.view(135, 120, 0.3, [0.01, 0.015, 0.058])
        report.add_figs_to_section([fig], ['Selected sources'],
                                   section='Source-level',
                                   replace=True)
        report.save(fname.report_html(subject=subject),
                    overwrite=True,
                    open_browser=False)

# Compute vertex pairs for which to compute connectivity
# (distances are based on the MRI of the first subject).
print('Computing connectivity pairs for all subjects...')
pairs = conpy.all_to_all_connectivity_pairs(fwd1, min_dist=min_pair_dist)

# Store the pairs in fsaverage space
subj1_to_fsaverage = conpy.utils.get_morph_src_mapping(
    fsaverage, fwd1['src'], indices=True, subjects_dir=fname.subjects_dir)[1]
pairs = [[subj1_to_fsaverage[v] for v in pairs[0]],
         [subj1_to_fsaverage[v] for v in pairs[1]]]
np.save(fname.pairs, pairs)
Esempio n. 4
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# going to use a forward model that defines less source points.

# Load an oct-4 forward model that has only a few source points
fwd_lim = mne.read_forward_solution(fwd_lim_fname)

# Restrict the forward model to gradiometers only
fwd_lim = mne.pick_types_forward(fwd_lim,
                                 meg='grad',
                                 eeg=False,
                                 exclude='bads')
fwd_lim = forward_to_tangential(fwd_lim)

###############################################################################
# To reduce the number of coherence computations even further, we're going to
# ignore all connections that span less than 5 centimeters.
pairs = all_to_all_connectivity_pairs(fwd_lim, min_dist=0.05)
print('There are now %d connectivity pairs' % len(pairs[0]))

###############################################################################
# Compute coherence between all defined pairs using DICS. This connectivity
# estimate will be dominated by local field spread effects, unless we make a
# contrast between two conditions.
con_noise = dics_connectivity(pairs, fwd_lim, csd_noise, reg=1)
con_signal = dics_connectivity(pairs, fwd_lim, csd_signal, reg=1)
con_contrast = con_signal - con_noise

# Create a cortical map, where the "signal" at each point is the sum of the
# coherence of all outgoing and incoming connections from and to that point.
all_to_all = con_contrast.make_stc('sum', weight_by_degree=True)

brain = all_to_all.plot('sample',
Esempio n. 5
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import conpy, mne  # Import required Python modules

# Read and convert a forward model to one that defines two orthogonal dipoles
# at each source, that are tangential to a sphere.
fwd = mne.read_forward_solution('sub002-fwd.fif')  # Read forward model
fwd_tan = conpy.forward_to_tangential(fwd_r)  # Convert to tangential model

# Pairs for which to compute connectivity. Use a distance threshold of 4 cm.
pairs = conpy.all_to_all_connectivity_pairs(fwd_tan, min_dist=0.04)

# Load CSD matrix
csd = conpy.read_csd('sub002-csd-face.h5')  # Read CSD for 'face' condition
csd = csd.mean(fmin=31, fmax=40)  # Obtain CSD for frequency band 31-40 Hz.

# Compute source connectivity using DICS. Try 50 orientations for each source
# point to find the orientation that maximizes coherence.
con = conpy.dics_connectivity(pairs, fwd_tan, csd, reg=0.05, n_angles=50)