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.
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 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 can wake up and know what time it is, sometimes to the exact minute.
But lately, I'm exactly one hour off.
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.
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.
Sysop: | Keyop |
---|---|
Location: | Huddersfield, West Yorkshire, UK |
Users: | 415 |
Nodes: | 16 (2 / 14) |
Uptime: | 92:43:47 |
Calls: | 8,690 |
Calls today: | 5 |
Files: | 13,250 |
Messages: | 5,947,019 |