{
  "id": 15325,
  "title": "Diagram of Electrode Channels",
  "url": "/competitions/grasp-and-lift-eeg-detection/discussion/15325",
  "author_name": "",
  "post_date": "2015-07-17T16:01:19.203Z",
  "votes": 1,
  "comment_count": 4,
  "views": 753,
  "content": "<p>I have two questions about the diagram of electrode channels ( <a href=\"https://www.kaggle.com/c/grasp-and-lift-eeg-detection/data\">https://www.kaggle.com/c/grasp-and-lift-eeg-detection/data</a>).</p>\n\n<p>First, what is the difference between dark nodes and white nodes ?</p>\n\n<p>Second, are the given data intended to not include all channels ?</p>",
  "messages": [
    {
      "id": "85850",
      "postDate": "07/17/2015 16:01:19",
      "content": "<p>I have two questions about the diagram of electrode channels ( <a href=\"https://www.kaggle.com/c/grasp-and-lift-eeg-detection/data\">https://www.kaggle.com/c/grasp-and-lift-eeg-detection/data</a>).</p>\n\n<p>First, what is the difference between dark nodes and white nodes ?</p>\n\n<p>Second, are the given data intended to not include all channels ?</p>",
      "rawMarkdown": "I have two questions about the diagram of electrode channels ( https://www.kaggle.com/c/grasp-and-lift-eeg-detection/data).\r\n\r\nFirst, what is the difference between dark nodes and white nodes ?\r\n\r\nSecond, are the given data intended to not include all channels ?",
      "votes": null
    },
    {
      "id": "85869",
      "postDate": "07/17/2015 18:55:11",
      "content": "<p>I was wondering the same thing.  Two of the channels that are numbered and included in the dataset are white on the diagram and it's not clear to me what that means.</p>",
      "rawMarkdown": "I was wondering the same thing.  Two of the channels that are numbered and included in the dataset are white on the diagram and it's not clear to me what that means.",
      "votes": null
    },
    {
      "id": "85930",
      "postDate": "07/18/2015 11:23:32",
      "content": "<p>I always assumed that the diagram was just a random diagram depicting general electrode locations and not specifically related to the trial data collected.</p>\n\n<p>If you look at the paper linked in the Data section it only claims to have recorded 32 channels so I don't think they're holding out additional channels from us.</p>",
      "rawMarkdown": "I always assumed that the diagram was just a random diagram depicting general electrode locations and not specifically related to the trial data collected.\r\n\r\nIf you look at the paper linked in the Data section it only claims to have recorded 32 channels so I don't think they're holding out additional channels from us.",
      "votes": null
    },
    {
      "id": "85939",
      "postDate": "07/18/2015 12:56:49",
      "content": "<p>There is an international system for placing electrodes called the 10/20 system. It uses 10 or 20 percent of the half circumference of the participants head, the nasion to inion distance and the preauricular point to the preauricular point. So the electrodes are placed very precisely over brain structures (like the motor cortex under the C line - C3, Cz, C4).</p>\n\n<p><a href=\"https://www.trans-cranial.com/local/manuals/10_20_pos_man_v1_0_pdf.pdf\">10/20 positioning system</a></p>\n\n<p>Although the vast majority of research currently is done with EEG caps that make the positioning of the electrodes a much simpler process. We do still make the undergraduates measure it out so they understand the placement.</p>\n\n<p>There is no significance to the black or white colouring of the electrodes in the diagrams.</p>\n\n<p>EEG amplifiers (and EEG caps) tend to come with a common number of channels. 16, 32 , 64 or 128 recording electrodes is common. So I don't think they are holding out individual electrode recordings from the data.</p>",
      "rawMarkdown": "There is an international system for placing electrodes called the 10/20 system. It uses 10 or 20 percent of the half circumference of the participants head, the nasion to inion distance and the preauricular point to the preauricular point. So the electrodes are placed very precisely over brain structures (like the motor cortex under the C line - C3, Cz, C4).\r\n\r\n[10/20 positioning system][1]\r\n\r\n\r\n  [1]: https://www.trans-cranial.com/local/manuals/10_20_pos_man_v1_0_pdf.pdf\r\n\r\nAlthough the vast majority of research currently is done with EEG caps that make the positioning of the electrodes a much simpler process. We do still make the undergraduates measure it out so they understand the placement.\r\n\r\nThere is no significance to the black or white colouring of the electrodes in the diagrams.\r\n\r\nEEG amplifiers (and EEG caps) tend to come with a common number of channels. 16, 32 , 64 or 128 recording electrodes is common. So I don't think they are holding out individual electrode recordings from the data.",
      "votes": null
    },
    {
      "id": "86130",
      "postDate": "07/20/2015 06:59:32",
      "content": "<p>@Alistair: You are absolutely correct. Thank you for your explanation.</p>",
      "rawMarkdown": "Alistair: You are absolutely correct. Thank you for your explanation.",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 85869,
      "author_name": "nickster86",
      "author_url": "",
      "post_date": "07/17/2015 18:55:11",
      "content": "<p>I was wondering the same thing.  Two of the channels that are numbered and included in the dataset are white on the diagram and it's not clear to me what that means.</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 85930,
      "author_name": "ajoo88",
      "author_url": "",
      "post_date": "07/18/2015 11:23:32",
      "content": "<p>I always assumed that the diagram was just a random diagram depicting general electrode locations and not specifically related to the trial data collected.</p>\n\n<p>If you look at the paper linked in the Data section it only claims to have recorded 32 channels so I don't think they're holding out additional channels from us.</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 85939,
      "author_name": "alistairwalsh",
      "author_url": "",
      "post_date": "07/18/2015 12:56:49",
      "content": "<p>There is an international system for placing electrodes called the 10/20 system. It uses 10 or 20 percent of the half circumference of the participants head, the nasion to inion distance and the preauricular point to the preauricular point. So the electrodes are placed very precisely over brain structures (like the motor cortex under the C line - C3, Cz, C4).</p>\n\n<p><a href=\"https://www.trans-cranial.com/local/manuals/10_20_pos_man_v1_0_pdf.pdf\">10/20 positioning system</a></p>\n\n<p>Although the vast majority of research currently is done with EEG caps that make the positioning of the electrodes a much simpler process. We do still make the undergraduates measure it out so they understand the placement.</p>\n\n<p>There is no significance to the black or white colouring of the electrodes in the diagrams.</p>\n\n<p>EEG amplifiers (and EEG caps) tend to come with a common number of channels. 16, 32 , 64 or 128 recording electrodes is common. So I don't think they are holding out individual electrode recordings from the data.</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 86130,
      "author_name": "qwlouse",
      "author_url": "",
      "post_date": "07/20/2015 06:59:32",
      "content": "<p>@Alistair: You are absolutely correct. Thank you for your explanation.</p>",
      "votes": null,
      "replies": []
    }
  ],
  "raw_markdown_by_id": {
    "85850": "I have two questions about the diagram of electrode channels ( https://www.kaggle.com/c/grasp-and-lift-eeg-detection/data).\r\n\r\nFirst, what is the difference between dark nodes and white nodes ?\r\n\r\nSecond, are the given data intended to not include all channels ?",
    "85869": "I was wondering the same thing.  Two of the channels that are numbered and included in the dataset are white on the diagram and it's not clear to me what that means.",
    "85930": "I always assumed that the diagram was just a random diagram depicting general electrode locations and not specifically related to the trial data collected.\r\n\r\nIf you look at the paper linked in the Data section it only claims to have recorded 32 channels so I don't think they're holding out additional channels from us.",
    "85939": "There is an international system for placing electrodes called the 10/20 system. It uses 10 or 20 percent of the half circumference of the participants head, the nasion to inion distance and the preauricular point to the preauricular point. So the electrodes are placed very precisely over brain structures (like the motor cortex under the C line - C3, Cz, C4).\r\n\r\n[10/20 positioning system][1]\r\n\r\n\r\n  [1]: https://www.trans-cranial.com/local/manuals/10_20_pos_man_v1_0_pdf.pdf\r\n\r\nAlthough the vast majority of research currently is done with EEG caps that make the positioning of the electrodes a much simpler process. We do still make the undergraduates measure it out so they understand the placement.\r\n\r\nThere is no significance to the black or white colouring of the electrodes in the diagrams.\r\n\r\nEEG amplifiers (and EEG caps) tend to come with a common number of channels. 16, 32 , 64 or 128 recording electrodes is common. So I don't think they are holding out individual electrode recordings from the data.",
    "86130": "Alistair: You are absolutely correct. Thank you for your explanation."
  },
  "source": "meta"
}