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Re: (meteorobs) Re: Nov 9/10 meteors not bad

>Norman,
>It was just a few weeks ago that you announced your having a "slump" during a
>recent observation a few hours prior to dawn and then picking up again. Any
>explanation for your deviation from your 1970's study?
>variations.  I think nodding off and alertness has become too much of a
>"whipping boy" for all inconsistencies with  meteor rates.
>George Z.

  George,
      I don't know if i'd go discounting 'alertness' as a "whipping boy".
  Though I know many of the active observers have years and years of
  experience, there are psychophysiological mecahnisms that we often don't
  have much control of.  To be sure, this is a most complex topic.  What I do
  know, though, is that if you deprive someone of sleep for, say, 48 hrs, and
  during the evening/early morn give them tasks to perform (vigilance-type
  tasks, alerting tasks, etc) regularly. And then make an x-y ploy of say,
  the percent correct or reaction times.  You see these beautiful circadain
  rhythms emerge.  In other words, there IS a circadian rhythm to ALERTNESS.
  If you ask the subject to judge how accurate THEY thought they were
  performing each time, often they will overestimate how well they did.  Ive
  done this with highly physically-trained NAVY SEALS (Special Forces), back
  when I was civilain employee with Navy. Actually, we sleep deprived some
  SEALS for 64 hours and pumped them up with caffeine, amphetamine or sugar
  pills.  Of course, there was alot of individual variability.

     Our bodies just aren't designed to stay up all night and be
  vigilant. That is why there is so much work being done on sleep research,
  shiftwork and the biological effects of light.

     Lastly, a few years back we rec'd funding to do portable EEG recordings
  on interstate truck drivers.  To study and possibly establish optimum
  sleep/drive schedules so as to maximize alertness and safety. These drivers
  weren't sleep deprived, but many were alittle overweight and suffered from
  sleep-disordered breathing (apnea) and, hence, many showed excessive daytime
  sleepiness.  We had sophisticated lane-tracking devices mounted of the top
  of the semi-trailer's cab to measure and record 'within-lane' weave or
  deviation.  Some of these guys were showing clear evidence of physiological
  REAL sleep (light sleep, that is) while DRIVING 55 MPH DOWN Interstate-80!
  And they were weaving within the lane more significantly than the non-sleepy
  drivers.  After we saw this, we inquired to the driver and he laughed and
  said "Sleeping? I wasn't sleeping. I was driving!"

    Can just hear myself now, "Hey Bob I wasn't sleeping! I was observing!"

    I am beginning to think that accounting for the rate variability is
  non-trivial task.  Especially when you have to consider variables like
  'perception'.  Maybe a 'circadian alertness' variable ought to also be
  added.  Maybe, if we all go "video", then we needn't worry about such
  things.  Sure we could go out and still observe, but we'd have the video be
  our 'objective data collector'

    Oh, and to answer LEW's question put to me re: other type of circadian
  rhythms.  Our lab just published study (Amer J of Physio) on eye and
  pupillary mearsures and possible circadian rhythms.  We found no significant
  circadian variations in these data.  That is, we took very precise serial
  measures of pupillary diamter (using video) and found that "Pupillary
  diameter does not demonstrate a clear circadian rhythm".   BTW, this was
  done in rabbits as well as humans.


     Joseph
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