BUG: Fix picks_artifact passed as exclude in regress_artifact

doc/changes/dev/14457.bugfix.rst

@@ -0,0 +1 @@
+Fix bug in :func:`mne.preprocessing.regress_artifact` where passing ``betas`` caused the ``picks_artifact`` value to be passed as ``exclude`` and the default ``picks_artifact="eog"`` to be used instead, by `Johannes Herforth`_.

mne/preprocessing/_regress.py

@@ -106,7 +106,9 @@ def regress_artifact(
         picks_artifact = _picks_to_idx(inst.info, picks_artifact)
         want_betas_shape = (len(picks), len(picks_artifact))
         _check_option("betas.shape", betas.shape, (want_betas_shape,))
-        model = EOGRegression(picks, picks_artifact, proj=proj)
+        model = EOGRegression(
+            picks=picks, exclude=exclude, picks_artifact=picks_artifact, proj=proj
+        )
         model.info_ = inst.info.copy()
         model.coef_ = betas
     return model.apply(inst, copy=copy), model.coef_

mne/preprocessing/tests/test_regress.py

@@ -37,6 +37,11 @@ def test_regress_artifact():
     assert orig_norm / 2 > clean_norm > orig_norm / 10
     with pytest.raises(ValueError, match=r"Invalid value.*betas\.shape.*"):
         regress_artifact(epochs, betas=betas[:-1])
+    # Non-default picks_artifact must be honored when betas are given
+    kwargs = dict(picks="eeg", picks_artifact=["EEG 001"])
+    epochs_clean, betas = regress_artifact(epochs, **kwargs)
+    epochs_betas, _ = regress_artifact(epochs, betas=betas, **kwargs)
+    assert_allclose(epochs_betas.get_data(), epochs_clean.get_data())
     # Regressing channels onto themselves should work
     epochs, betas = regress_artifact(epochs, picks="eog", picks_artifact="eog")
     assert np.ptp(epochs.get_data("eog")) < 1e-15  # constant value