# The following electrodes have overlapping positions, which causes problems during visualization: VPVA, VNVB, HPHL, HNHR, Erbs, OrbOcc, Mass

**URL:** <https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216>\
**Category:** Support & Discussions\
**Created:** [July 4, 2022, 7:29pm UTC](https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216 "2022-07-04T19:29:36Z")\
**Posts on this page:** 11\
**Page:** 1

<div class="post-metadata">

**Author:** ![rajesh9121](https://avatars.discourse-cdn.com/v4/letter/r/34f0e0/32.png) [@rajesh9121](https://mne.discourse.group/u/rajesh9121)\
**Post date:** [July 4, 2022, 7:29pm UTC](https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216/1 "2022-07-04T19:29:37Z")

</div>

**The following electrodes have overlapping positions, which causes problems during visualization:  
VPVA, VNVB, HPHL, HNHR, Erbs, OrbOcc, Mass**

- MNE version: e.g. 0.24.0
- operating system: e.g. macOS 12 / Windows 10 / Ubuntu 18.04

**📄**

 ![Screenshot (181)](https://global.discourse-cdn.com/free1/uploads/mne/original/2X/8/8976c3e988575d70d627ef33bacc713bfca03051.png)   
**Please also provide relevant code snippets – ideally a [minimal working example](https://stackoverflow.com/help/minimal-reproducible-example) (MWE).**

🖋 To get the correct formatting, paste your Python code, then select it, and click on the **Preformatted text** toolbar button.

**📵 Please avoid sharing screenshots of code and error messages!** Screenshots are difficult to work with especially on mobile devices; they don’t allow others to copy code and other text; and they don’t show up in the search.

👉 👉 👉 Please edit or remove the above text before submitting your posting. 👈 👈 👈

---

<div class="post-metadata">

**Author:** ![richard](https://yyz2.discourse-cdn.com/free1/user_avatar/mne.discourse.group/richard/32/15_2.png) [@richard](https://mne.discourse.group/u/richard)\
**Post date:** [July 4, 2022, 8:55pm UTC](https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216/2 "2022-07-04T20:55:10Z")

</div>

Hello @rajesh9121, and welcome to the forum!

Unfortunately, you don’t provide enough information for us to fully grasp the issue, so we can only guess. I assume that all mentioned sensors have been assigned location `(0, 0, 0)`.

You can check this by looking at the montage:

```python
montage = raw.get_montage()
print(montage.dig)

```

Do you actually need these channels in your analysis? They bear quite uncommon names.

Best wishes,  
Richard

---

<div class="post-metadata">

**Author:** ![rajesh9121](https://avatars.discourse-cdn.com/v4/letter/r/34f0e0/32.png) [@rajesh9121](https://mne.discourse.group/u/rajesh9121)\
**Post date:** [July 5, 2022, 2:25am UTC](https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216/3 "2022-07-05T02:25:30Z")

</div>

![Screenshot (182)](https://global.discourse-cdn.com/free1/uploads/mne/original/2X/8/87813a96510bad93f5a46e40028bedf541d49e5e.png)  
here is the result of the above query  
montage = raw.get\_montage()  
print(montage.dig)  
 ![image](https://global.discourse-cdn.com/free1/uploads/mne/original/2X/e/e2ed80c88f9b48b71062a855101feed9d7ab97f7.png)

---

<div class="post-metadata">

**Author:** ![rajesh9121](https://avatars.discourse-cdn.com/v4/letter/r/34f0e0/32.png) [@rajesh9121](https://mne.discourse.group/u/rajesh9121)\
**Post date:** [July 5, 2022, 4:45am UTC](https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216/4 "2022-07-05T04:45:17Z")

</div>

can you help me… actually iam watching your videos on youtube channel. in my data projection data not found. and position of electrodes also not there

---

<div class="post-metadata">

**Author:** ![richard](https://yyz2.discourse-cdn.com/free1/user_avatar/mne.discourse.group/richard/32/15_2.png) [@richard](https://mne.discourse.group/u/richard)\
**Post date:** [July 5, 2022, 5:50am UTC](https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216/5 "2022-07-05T05:50:48Z")

</div>

Hello, can you please paste the output as text and not as screenshots, they’re extremely difficult to work with for me as I’m using the forum mostly from my phone. Copy & paste the text, select it, and click on the Preformatted text button in the toolbar to ensure it gets displayed correctly. Thank you.

---

<div class="post-metadata">

**Author:** ![rajesh9121](https://avatars.discourse-cdn.com/v4/letter/r/34f0e0/32.png) [@rajesh9121](https://mne.discourse.group/u/rajesh9121)\
**Post date:** [July 5, 2022, 6:40am UTC](https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216/6 "2022-07-05T06:40:52Z")

</div>

```python
Fitting ICA to data using 33 channels (please be patient, this may take a while)
Selecting by number: 20 components
C:\Users\alaja\AppData\Local\Temp\ipykernel_22168\1702439165.py:2: RuntimeWarning: The data has not been high-pass filtered. For good ICA performance, it should be high-pass filtered (e.g., with a 1.0 Hz lower bound) before fitting ICA.
  ica.fit(raw)
Fitting ICA took 7.8s.
    Using multitaper spectrum estimation with 7 DPSS windows
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
~\AppData\Local\Temp\ipykernel_22168\1702439165.py in <cell line: 4>()
      2 ica.fit(raw)
      3 ica.exclude = [1, 2] # details on how we picked these are omitted here
----> 4 ica.plot_properties(raw, picks=ica.exclude)

~\anaconda3\envs\mne\lib\site-packages\mne\preprocessing\ica.py in plot_properties(self, inst, picks, axes, dB, plot_std, topomap_args, image_args, psd_args, figsize, show, reject, reject_by_annotation, verbose)
   1950 psd_args=None, figsize=None, show=True, reject='auto',
   1951 reject_by_annotation=True, *, verbose=None):
-> 1952 return plot_ica_properties(self, inst, picks=picks, axes=axes,
   1953 dB=dB, plot_std=plot_std,
   1954 topomap_args=topomap_args,

<decorator-gen-186> in plot_ica_properties(ica, inst, picks, axes, dB, plot_std, topomap_args, image_args, psd_args, figsize, show, reject, reject_by_annotation, verbose)

~\anaconda3\envs\mne\lib\site-packages\mne\viz\ica.py in plot_ica_properties(ica, inst, picks, axes, dB, plot_std, topomap_args, image_args, psd_args, figsize, show, reject, reject_by_annotation, verbose)
    334 .. versionadded:: 0.13
    335 """
--> 336 return _fast_plot_ica_properties(ica, inst, picks=picks, axes=axes, dB=dB,
    337 plot_std=plot_std,
    338 topomap_args=topomap_args,

~\anaconda3\envs\mne\lib\site-packages\mne\viz\ica.py in _fast_plot_ica_properties(ica, inst, picks, axes, dB, plot_std, topomap_args, image_args, psd_args, figsize, show, reject, precomputed_data, reject_by_annotation, verbose)
    446 
    447 # the actual plot
--> 448 fig = _plot_ica_properties(
    449 pick, ica, inst, psds_mean, freqs, ica_data.shape[1],
    450 epoch_var, plot_lowpass_edge,

~\anaconda3\envs\mne\lib\site-packages\mne\viz\ica.py in _plot_ica_properties(pick, ica, inst, psds_mean, freqs, n_trials, epoch_var, plot_lowpass_edge, epochs_src, set_title_and_labels, plot_std, psd_ylabel, spectrum_std, topomap_args, image_args, fig, axes, kind, dropped_indices)
    147 # --------
    148 # component topomap
--> 149 _plot_ica_topomap(ica, pick, show=False, axes=topo_ax, **topomap_args)
    150 
    151 # image and erp

~\anaconda3\envs\mne\lib\site-packages\mne\viz\topomap.py in _plot_ica_topomap(ica, idx, ch_type, res, vmin, vmax, cmap, colorbar, title, show, outlines, contours, image_interp, axes, sensors, allow_ref_meg, extrapolate, sphere, border)
   1046 data = ica.get_components()[:, idx]
   1047 data_picks, pos, merge_channels, names, _, sphere, clip_origin = \
-> 1048 _prepare_topomap_plot(ica, ch_type, sphere=sphere)
   1049 data = data[data_picks]
   1050 outlines = _make_head_outlines(sphere, pos, outlines, clip_origin)

~\anaconda3\envs\mne\lib\site-packages\mne\viz\topomap.py in _prepare_topomap_plot(inst, ch_type, sphere)
     82 
     83 # special case for merging grad channels
---> 84 layout = find_layout(info)
     85 if (ch_type == 'grad' and layout is not None and
     86 (layout.kind.startswith('Vectorview') or

~\anaconda3\envs\mne\lib\site-packages\mne\channels\layout.py in find_layout(info, ch_type, exclude)
    424 raise RuntimeError('Cannot make EEG layout, no measurement info '
    425 'was passed to `find_layout`')
--> 426 return make_eeg_layout(info, exclude=exclude)
    427 elif has_csd_coils and ch_type in [None, 'csd']:
    428 return make_eeg_layout(info, exclude=exclude, csd=True)

~\anaconda3\envs\mne\lib\site-packages\mne\channels\layout.py in make_eeg_layout(info, radius, width, height, exclude, csd)
    260 pick_kwargs.update(csd=True, eeg=False)
    261 picks = pick_types(info, **pick_kwargs)
--> 262 loc2d = _find_topomap_coords(info, picks)
    263 names = [info['chs'][i]['ch_name'] for i in picks]
    264 

~\anaconda3\envs\mne\lib\site-packages\mne\channels\layout.py in _find_topomap_coords(info, picks, layout, ignore_overlap, to_sphere, sphere)
    623 pos = np.asarray(pos)
    624 else:
--> 625 pos = _auto_topomap_coords(
    626 info, picks, ignore_overlap=ignore_overlap, to_sphere=to_sphere,
    627 sphere=sphere)

~\anaconda3\envs\mne\lib\site-packages\mne\channels\layout.py in _auto_topomap_coords(info, picks, ignore_overlap, to_sphere, sphere)
    722 ]
    723 
--> 724 raise ValueError('The following electrodes have overlapping positions,'
    725 ' which causes problems during visualization:\n' +
    726 ', '.join(problematic_electrodes))

ValueError: The following electrodes have overlapping positions, which causes problems during visualization:
VPVA, VNVB, HPHL, HNHR, Erbs, OrbOcc, Mass

```

---

<div class="post-metadata">

**Author:** ![rajesh9121](https://avatars.discourse-cdn.com/v4/letter/r/34f0e0/32.png) [@rajesh9121](https://mne.discourse.group/u/rajesh9121)\
**Post date:** [July 5, 2022, 6:44am UTC](https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216/7 "2022-07-05T06:44:11Z")

</div>

```python
[quote="rajesh9121, post:3, topic:5216"]
montage = raw.get_montage()
print(montage.dig)
[/quote]

#CHOOSE WHICH RAW FILE TO RUN IN NEXT TWO LINES BELOW!!!
#raw = mne.io.read_raw_edf(raw_data_file, preload=True)
# THE EMOTIV FLEX EDF FILE IS CALLED: raw_qtest_file
raw = mne.io.read_raw_brainvision('numinous_test_data/ses-1/eeg/sub-19681349_ses-1_task-restEC_eeg.vhdr',preload=True)

#raw = mne.io.read_raw_edf('numinous_test_data/ses-1/eeg/sub-19681349_ses-1_task-restEC_eeg.vhdr', preload=True)
#raw = mne.io.read_raw_edf(raw_5meo2, preload=True)

print(raw.info)

print(raw.info['dig'])

ch_names = raw.info['ch_names'] 
ch_types = ['eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg',
           'eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg','eeg']
info = mne.create_info(ch_names=ch_names, sfreq=256, ch_types=ch_types)
raw.info = info
print(raw.info)

montage_kind = "standard_1020"
montage = mne.channels.make_standard_montage(montage_kind)
raw.set_montage(montage, match_case=False,on_missing='ignore')

#THIS confirms that we have now added the digitization points
print(raw.info['dig'])

#The plots below rely on digitzation points being added: 
#raw.plot_projs_topomap()
raw.plot_psd_topo()
raw.plot_sensors()
montage.plot()
#print(raw.info["sfreq"])
#raw.plot_projs_topomap() #### OF COURSE THIS LEADS TO A ZERO DIVISION ERROR SINCE THERE ARE NO PROJECTIONS IN ANY OF OUR FILES AS INDICATED IN: print(raw.info)
#ICA.plot_components(raw)

<Info | 7 non-empty values
 bads: []
 ch_names: Fp1, Fp2, F7, F3, Fz, F4, F8, FC3, FCz, FC4, T7, C3, Cz, C4, T8, ...
 chs: 33 EEG
 custom_ref_applied: False
 highpass: 0.0 Hz
 lowpass: 250.0 Hz
 meas_date: unspecified
 nchan: 33
 projs: []
 sfreq: 500.0 Hz
>
None
<Info | 7 non-empty values
 bads: []
 ch_names: Fp1, Fp2, F7, F3, Fz, F4, F8, FC3, FCz, FC4, T7, C3, Cz, C4, T8, ...
 chs: 33 EEG
 custom_ref_applied: False
 highpass: 0.0 Hz
 lowpass: 128.0 Hz
 meas_date: unspecified
 nchan: 33
 projs: []
 sfreq: 256.0 Hz
>
[<DigPoint | LPA : (-82.5, 0.0, 0.0) mm : head frame>, <DigPoint | Nasion : (-0.0, 114.0, 0.0) mm : head frame>, <DigPoint | RPA : (82.5, -0.0, -0.0) mm : head frame>, <DigPoint | EEG #1 : (-30.9, 114.6, 27.9) mm : head frame>, <DigPoint | EEG #3 : (28.4, 115.3, 27.7) mm : head frame>, <DigPoint | EEG #16 : (-71.9, 73.1, 25.8) mm : head frame>, <DigPoint | EEG #18 : (-51.8, 86.7, 78.7) mm : head frame>, <DigPoint | EEG #20 : (-1.2, 93.3, 102.6) mm : head frame>, <DigPoint | EEG #22 : (50.3, 87.4, 77.3) mm : head frame>, <DigPoint | EEG #24 : (71.4, 74.5, 25.1) mm : head frame>, <DigPoint | EEG #29 : (-61.9, 57.1, 93.8) mm : head frame>, <DigPoint | EEG #31 : (-1.3, 63.5, 126.6) mm : head frame>, <DigPoint | EEG #33 : (60.6, 57.7, 93.8) mm : head frame>, <DigPoint | EEG #38 : (-86.0, 14.9, 31.2) mm : head frame>, <DigPoint | EEG #40 : (-67.1, 23.4, 104.5) mm : head frame>, <DigPoint | EEG #42 : (-1.4, 27.6, 140.2) mm : head frame>, <DigPoint | EEG #44 : (65.3, 23.6, 103.7) mm : head frame>, <DigPoint | EEG #46 : (83.3, 15.3, 31.0) mm : head frame>, <DigPoint | EEG #51 : (-65.5, -11.9, 107.8) mm : head frame>, <DigPoint | EEG #53 : (-1.5, -10.5, 141.5) mm : head frame>, <DigPoint | EEG #55 : (64.7, -12.0, 107.7) mm : head frame>, <DigPoint | EEG #60 : (-74.5, -42.1, 41.3) mm : head frame>, <DigPoint | EEG #62 : (-55.0, -44.2, 99.9) mm : head frame>, <DigPoint | EEG #64 : (-1.7, -45.2, 126.7) mm : head frame>, <DigPoint | EEG #66 : (53.6, -44.3, 100.5) mm : head frame>, <DigPoint | EEG #68 : (71.0, -42.3, 41.2) mm : head frame>, <DigPoint | EEG #81 : (-31.6, -80.6, 54.8) mm : head frame>, <DigPoint | EEG #82 : (-2.1, -82.8, 60.7) mm : head frame>, <DigPoint | EEG #83 : (27.7, -80.5, 54.7) mm : head frame>]
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
~\AppData\Local\Temp\ipykernel_5452\2638937880.py in <cell line: 29>()
     27 #The plots below rely on digitzation points being added:
     28 #raw.plot_projs_topomap()
---> 29 raw.plot_psd_topo()
     30 raw.plot_sensors()
     31 montage.plot()

~\anaconda3\envs\mne\lib\site-packages\mne\io\base.py in plot_psd_topo(self, tmin, tmax, fmin, fmax, proj, n_fft, n_overlap, layout, color, fig_facecolor, axis_facecolor, dB, show, block, n_jobs, axes, verbose)
   1589 show=True, block=False, n_jobs=1, axes=None,
   1590 verbose=None):
-> 1591 return plot_raw_psd_topo(self, tmin=tmin, tmax=tmax, fmin=fmin,
   1592 fmax=fmax, proj=proj, n_fft=n_fft,
   1593 n_overlap=n_overlap, layout=layout,

<decorator-gen-184> in plot_raw_psd_topo(raw, tmin, tmax, fmin, fmax, proj, n_fft, n_overlap, layout, color, fig_facecolor, axis_facecolor, dB, show, block, n_jobs, axes, verbose)

~\anaconda3\envs\mne\lib\site-packages\mne\viz\raw.py in plot_raw_psd_topo(raw, tmin, tmax, fmin, fmax, proj, n_fft, n_overlap, layout, color, fig_facecolor, axis_facecolor, dB, show, block, n_jobs, axes, verbose)
    500 if layout is None:
    501 from ..channels.layout import find_layout
--> 502 layout = find_layout(raw.info)
    503 
    504 psds, freqs = psd_welch(raw, tmin=tmin, tmax=tmax, fmin=fmin,

~\anaconda3\envs\mne\lib\site-packages\mne\channels\layout.py in find_layout(info, ch_type, exclude)
    424 raise RuntimeError('Cannot make EEG layout, no measurement info '
    425 'was passed to `find_layout`')
--> 426 return make_eeg_layout(info, exclude=exclude)
    427 elif has_csd_coils and ch_type in [None, 'csd']:
    428 return make_eeg_layout(info, exclude=exclude, csd=True)

~\anaconda3\envs\mne\lib\site-packages\mne\channels\layout.py in make_eeg_layout(info, radius, width, height, exclude, csd)
    260 pick_kwargs.update(csd=True, eeg=False)
    261 picks = pick_types(info, **pick_kwargs)
--> 262 loc2d = _find_topomap_coords(info, picks)
    263 names = [info['chs'][i]['ch_name'] for i in picks]
    264 

~\anaconda3\envs\mne\lib\site-packages\mne\channels\layout.py in _find_topomap_coords(info, picks, layout, ignore_overlap, to_sphere, sphere)
    623 pos = np.asarray(pos)
    624 else:
--> 625 pos = _auto_topomap_coords(
    626 info, picks, ignore_overlap=ignore_overlap, to_sphere=to_sphere,
    627 sphere=sphere)

~\anaconda3\envs\mne\lib\site-packages\mne\channels\layout.py in _auto_topomap_coords(info, picks, ignore_overlap, to_sphere, sphere)
    722 ]
    723 
--> 724 raise ValueError('The following electrodes have overlapping positions,'
    725 ' which causes problems during visualization:\n' +
    726 ', '.join(problematic_electrodes))

ValueError: The following electrodes have overlapping positions, which causes problems during visualization:
VPVA, VNVB, HPHL, HNHR, Erbs, OrbOcc, Mass

```

---

<div class="post-metadata">

**Author:** ![richard](https://yyz2.discourse-cdn.com/free1/user_avatar/mne.discourse.group/richard/32/15_2.png) [@richard](https://mne.discourse.group/u/richard)\
**Post date:** [July 5, 2022, 8:09am UTC](https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216/8 "2022-07-05T08:09:47Z")

</div>

The electrodes VPVA, VNVB, HPHL, HNHR, Erbs, OrbOcc, Mass don’t have digitization points associated with them, hence you cannot plot a topographic map that includes these channels. Are these proper EEG channels or what are those anyway? Maybe you should just set their channel type to `misc` if they don’t include any EEG data anyway…

---

<div class="post-metadata">

**Author:** ![rajesh9121](https://avatars.discourse-cdn.com/v4/letter/r/34f0e0/32.png) [@rajesh9121](https://mne.discourse.group/u/rajesh9121)\
**Post date:** [July 5, 2022, 2:15pm UTC](https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216/9 "2022-07-05T14:15:25Z")

</div>

```python
[20]:

events = mne.find_events(raw_EC, stim_channel='Fp1')

events

[20]:

array([], shape=(0, 3), dtype=int32)

```

richard event array is showing empty… what should i do in this case

---

<div class="post-metadata">

**Author:** ![richard](https://yyz2.discourse-cdn.com/free1/user_avatar/mne.discourse.group/richard/32/15_2.png) [@richard](https://mne.discourse.group/u/richard)\
**Post date:** [July 5, 2022, 6:15pm UTC](https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216/10 "2022-07-05T18:15:49Z")

</div>

This seems like an unrelated question to me. Please open a new topic for new questions. Thank you!

---

<div class="post-metadata">

**Author:** ![ImRawwk](https://yyz2.discourse-cdn.com/free1/user_avatar/mne.discourse.group/imrawwk/32/1703_2.png) [@ImRawwk](https://mne.discourse.group/u/ImRawwk)\
**Post date:** [July 8, 2022, 11:02am UTC](https://mne.discourse.group/t/the-following-electrodes-have-overlapping-positions-which-causes-problems-during-visualization-vpva-vnvb-hphl-hnhr-erbs-orbocc-mass/5216/11 "2022-07-08T11:02:45Z")

</div>

I have marked these 7 channels as misc but I am still getting the same error - ValueError: The following electrodes have overlapping positions, which causes problems during visualization:  
VPVA, VNVB, HPHL, HNHR, Erbs, OrbOcc, Mass