• Nerve cells in blind mice retain their visual function

    From Jan Panteltje@21:1/5 to All on Fri Nov 29 06:02:51 2024
    Nerve cells of blind mice retain their visual function
    Nerve cells in the retina were analysed using microelectrodes
    https://www.sciencedaily.com/releases/2024/11/241126135552.htm
    Summary:
    Using microelectrodes, scientists could show that cells in the retina play different roles.
    The produce different signals, which is important for the processing of visual information.
    These differences are remarkably stable and still persist in the retina of blind animals.
    This is important for retinal implants.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to Jan Panteltje on Fri Nov 29 09:04:00 2024
    Jan Panteltje <alien@comet.invalid> wrote:

    Nerve cells of blind mice retain their visual function
    Nerve cells in the retina were analysed using microelectrodes
    https://www.sciencedaily.com/releases/2024/11/241126135552.htm
    Summary:
    Using microelectrodes, scientists could show that cells in the retina
    play different roles. The produce different signals, which is important
    for the processing of visual information. These differences are
    remarkably stable and still persist in the retina of blind animals. This
    is important for retinal implants.

    I recently heard that the presence of a third type of photoreceptor cell
    has been detected in the human eye. As well as rods and cones, there is
    a more primitive light-sensitive mechanism for setting the body clock.
    People who are completely blind can still maintain a synchronous diurnal rhythm, but if they have had their eyes surgically removed, their
    rhythms no longer synchronise with daylight.

    As far as I know, the extra cells have not yet been identified and their presence is only inferred from their apparent synchronising effect.


    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
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  • From Jan Panteltje@21:1/5 to Liz Tuddenham on Fri Nov 29 10:02:34 2024
    On a sunny day (Fri, 29 Nov 2024 09:04:00 +0000) it happened liz@poppyrecords.invalid.invalid (Liz Tuddenham) wrote in <1r3s0wg.18a0tha1jgpo5cN%liz@poppyrecords.invalid.invalid>:

    Jan Panteltje <alien@comet.invalid> wrote:

    Nerve cells of blind mice retain their visual function
    Nerve cells in the retina were analysed using microelectrodes
    https://www.sciencedaily.com/releases/2024/11/241126135552.htm
    Summary:
    Using microelectrodes, scientists could show that cells in the retina
    play different roles. The produce different signals, which is important
    for the processing of visual information. These differences are
    remarkably stable and still persist in the retina of blind animals. This
    is important for retinal implants.

    I recently heard that the presence of a third type of photoreceptor cell
    has been detected in the human eye. As well as rods and cones, there is
    a more primitive light-sensitive mechanism for setting the body clock.
    People who are completely blind can still maintain a synchronous diurnal >rhythm, but if they have had their eyes surgically removed, their
    rhythms no longer synchronise with daylight.

    As far as I know, the extra cells have not yet been identified and their >presence is only inferred from their apparent synchronising effect.

    Vision is an interesting thing, been involved with TV tech from very young age. One technician we had in the color studios was color-blind..
    How he ever managed to do things is still a mystery to me.
    As to daily rhythms.. worked in shifts for many years..
    I do have good night/low-light vision..
    Still playing with cameras now and then.. IR and what not.

    Nature is very inventive..
    Anyways would be nice if we could give vision back in a simple way to people that lost it.

    --- SoupGate-Win32 v1.05
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  • From Crash Gordon@21:1/5 to Liz Tuddenham on Fri Nov 29 12:16:54 2024
    On 11/29/2024 3:04 AM, Liz Tuddenham wrote:
    I recently heard that the presence of a third type of photoreceptor cell
    has been detected in the human eye. As well as rods and cones, there is
    a more primitive light-sensitive mechanism for setting the body clock.

    I was recently in the room with a relative who was being tested with an
    unusual method. They were asked to look at a target, close their eyes,
    and then touch the target. They missed by several inches. Then the Dr.
    would put a colored filter in front of their eyes *after* the eyes were
    closed -- and certain colors would improve their ability to find the
    target. I would not have believed it if I had not watched it personally.

    There's a video of the technique here: https://www.youtube.com/watch?v=qA_tjGCFzgg
    using a ringing bell instead of a visual target. The video doesn't
    point out that the test is done with eyes closed, but it is.

    It takes several weeks to adjust to wearing the special glasses that are prescribed; at first my relative could only wear them for two or three
    minutes lying down in a dark room with eyes closed, before feeling
    dizzy. After a month or so they had built up to the point of being able
    to wear them all day. And the glasses* were a big help in treating
    their symptoms.

    I asked the Dr. how colored lenses could have any effect on closed eyes,
    and they said that there are pathways from eye to brain that are very
    sensitive to light but do not connect to the visual cortex. It's pretty amazing to see it in action.

    =====
    *BTW the colored filters are used only for diagnostic purposes. The
    glasses themselves are not colored.

    --
    I'm part of the vast libertarian conspiracy to take over the world and
    leave everyone alone.

    --- SoupGate-Win32 v1.05
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  • From Jeff Layman@21:1/5 to john larkin on Fri Nov 29 19:45:19 2024
    On 29/11/2024 19:16, john larkin wrote:

    I can wake up and know what time it is, sometimes to the exact minute.

    I have pretty accurate time sensing at any time of the day - usually
    within a few minutes even if I haven't looked at a watch for a few
    hours. I have no idea why I can do this, but assume my brain has an
    internal clock somewhere. But why does it work in hours and minutes?

    But lately, I'm exactly one hour off.

    When did your clocks go back an hour?

    --
    Jeff

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to Liz Tuddenham on Fri Nov 29 11:16:06 2024
    On Fri, 29 Nov 2024 09:04:00 +0000, liz@poppyrecords.invalid.invalid
    (Liz Tuddenham) wrote:

    Jan Panteltje <alien@comet.invalid> wrote:

    Nerve cells of blind mice retain their visual function
    Nerve cells in the retina were analysed using microelectrodes
    https://www.sciencedaily.com/releases/2024/11/241126135552.htm
    Summary:
    Using microelectrodes, scientists could show that cells in the retina
    play different roles. The produce different signals, which is important
    for the processing of visual information. These differences are
    remarkably stable and still persist in the retina of blind animals. This
    is important for retinal implants.

    I recently heard that the presence of a third type of photoreceptor cell
    has been detected in the human eye. As well as rods and cones, there is
    a more primitive light-sensitive mechanism for setting the body clock.
    People who are completely blind can still maintain a synchronous diurnal >rhythm, but if they have had their eyes surgically removed, their
    rhythms no longer synchronise with daylight.

    As far as I know, the extra cells have not yet been identified and their >presence is only inferred from their apparent synchronising effect.

    I can wake up and know what time it is, sometimes to the exact minute.

    But lately, I'm exactly one hour off.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to All on Fri Nov 29 11:18:47 2024
    On Fri, 29 Nov 2024 12:16:54 -0600, Crash Gordon <uucp@crashelex.com>
    wrote:

    On 11/29/2024 3:04 AM, Liz Tuddenham wrote:
    I recently heard that the presence of a third type of photoreceptor cell
    has been detected in the human eye. As well as rods and cones, there is
    a more primitive light-sensitive mechanism for setting the body clock.

    I was recently in the room with a relative who was being tested with an >unusual method. They were asked to look at a target, close their eyes,
    and then touch the target. They missed by several inches. Then the Dr. >would put a colored filter in front of their eyes *after* the eyes were >closed -- and certain colors would improve their ability to find the
    target. I would not have believed it if I had not watched it personally.

    There's a video of the technique here: >https://www.youtube.com/watch?v=qA_tjGCFzgg
    using a ringing bell instead of a visual target. The video doesn't
    point out that the test is done with eyes closed, but it is.

    It takes several weeks to adjust to wearing the special glasses that are >prescribed; at first my relative could only wear them for two or three >minutes lying down in a dark room with eyes closed, before feeling
    dizzy. After a month or so they had built up to the point of being able
    to wear them all day. And the glasses* were a big help in treating
    their symptoms.

    I asked the Dr. how colored lenses could have any effect on closed eyes,
    and they said that there are pathways from eye to brain that are very >sensitive to light but do not connect to the visual cortex. It's pretty >amazing to see it in action.

    =====
    *BTW the colored filters are used only for diagnostic purposes. The
    glasses themselves are not colored.

    I can sense hot objects in a room by skin feel, thermal IR receptors
    of some sort. Directionality is poor.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)