LSDBase

9 Comments:

• 

  Evan Jones

  2012-09-06 at 2349

  Michael,
  When you say “blinks” do you mean rapid eye movements that are indicative of REM sleep?

  Reply
  • 

    Michael Paul Coder

    2012-09-07 at 2241

    I want to believe so. I have found that there are three distinct types of eye movements.

    1.) Flutters, the conventional rapid eye movements – that last around 100 milliseconds and occur a few times a second:

    

    2.) Blinks, that last for up to 1.5 seconds and occur every few seconds:

    

    3.) Ticks, or fast blinks, that last for 100 milliseconds and occur every few seconds:

    

    Reply
    • 

      Evan Jones

      2012-09-08 at 0103

      Are all three of those graphs taken from your actual sleep recordings?

      Reply
      • 

        Michael Paul Coder

        2012-09-08 at 0118

        Yes, as are 99% of the recordings in the database.

        Reply
        • 

          Evan Jones

          2012-09-08 at 0133

          Reason I ask is that I believe the first graph is indicative of true REM while the latter two are showing some kind of artifact activity. Rapid Eye Movement in dream sleep is very sporadic/random and does not follow a set tempo. Here’s a good example of how REM looks (LOC & ROC show eye activity; electrooculogram):

          

          Since those “blinks” in your 2nd and 3rd frames are occurring exactly every few seconds and lasting longer than an instant, I would believe it’s artifact from breathing.

          If your wires on the Halograph/actograph set-up don’t have enough slack while you are laying down, this could cause “respiratory” artifact in the reading because your body is pulling on the wires each time you inhale or exhale.

          I used to be a polysomnologist (sleep technologist) and I saw this artifact pretty often. I could be wrong, but if I’m right then it should help you avoid false positives.

          Reply
          • 

            Michael Paul Coder

            2012-09-08 at 2050

            Wow. Thanks! That would also explain the vibrations I have been seeing as simply rolling into the position in which the wires don’t have enough slack.

            I will focus my attention on the true eye movements and retrain the algorithms to detect them more selectively. Thank you for the advice – you have probably saved me a good year of research.

            Reply
            • 

              Evan Jones

              2012-09-09 at 0045

              Glad to help out however I can. If the respiratory artifact continues, I can explain a few tricks to avoid them.

              By the way, what’s your main email address?

              Reply
              • 

                Michael Paul Coder

                2012-09-09 at 1311

                That would be great. It might even be of value to include an optional wire as a plug-in to always pick up the respiratory artifact for those interested in monitoring the breathing patterns throughout the night?

                My main account is mcoder at the lucid-code.com domain.

                Reply
              • 

                Sebastiii

                2022-01-28 at 0857

                Hi,
                For sure, respiratory artifact is really to avoid 😉
                That new “Toss” feature should eliminate.

                Reply