3 ms·

18 is conspicuously missing, is anyone (everyone?) incapable of extending both their thumb and their ring finger? Or extending their ring finger alone, without

by pliny 11y ago

18 is conspicuously missing, is anyone (everyone?) incapable of extending both their thumb and their ring finger? Or extending their ring finger alone, without using their thumb to hold down the middle finger?

gamegoblin 11y ago
I came here to ask this same question. On my right hand, I can move my ring finger as independently as any other, but on my left hand, I cannot extend it fully by itself. I can extend it if I simultaneously extend the adjacent pinky, but not alone.
- omegaham 11y ago
  Interesting - I can't do it with either hand. If I bring my ring finger out, the pinky comes out too unless it's held in place by my thumb.
jacobolus 11y ago
The muscle which extends the ring finger (at the MP joint at the base of the finger) also extends the middle finger. It’s basically impossible (for me at least) to simultaneously flex the middle finger at that joint while extending the ring finger, unless I relax the relevant muscles and use some other force (e.g. my other hand) to hold my middle finger down or my ring finger up. More generally, there are lots of shared muscles between the last three fingers and especially between middle and ring fingers, so moving them with some degree of independence takes training and isn’t ever perfect. The index finger and thumb are much more independent and flexible. You can flex the middle joint on the middle finger while mostly extending the ring finger, to sort of make a passable #18 by the scheme in the wiki article. Overall though that binary counting method isn’t all that well aligned with comfortable finger motions. A better one could probably be developed, but it might be a bit more complex. http://www.madsci.org/posts/archives/2005-05/1117326759.An.r.html http://www.madsci.org/posts/archives/2005-05/1117326759.An.r...
e12e 11y ago
If you lock your fist, you can extend your ring finger, then your thumb -- leaving the other three fingers "hanging" in your fist. Will probably be a little painful, and won't be pretty -- but it's (sort-of) possible.
kyberias 11y ago
I can do that with both hands starting from the ring finger's second joint. Right hands is significantly weaker and it kinda hurts to do that.

by pliny 11y ago

gamegoblin 11y ago

I came here to ask this same question. On my right hand, I can move my ring finger as independently as any other, but on my left hand, I cannot extend it fully by itself. I can extend it if I simultaneously extend the adjacent pinky, but not alone.

omegaham 11y ago
Interesting - I can't do it with either hand. If I bring my ring finger out, the pinky comes out too unless it's held in place by my thumb.

jacobolus 11y ago

The muscle which extends the ring finger (at the MP joint at the base of the finger) also extends the middle finger. It’s basically impossible (for me at least) to simultaneously flex the middle finger at that joint while extending the ring finger, unless I relax the relevant muscles and use some other force (e.g. my other hand) to hold my middle finger down or my ring finger up. More generally, there are lots of shared muscles between the last three fingers and especially between middle and ring fingers, so moving them with some degree of independence takes training and isn’t ever perfect. The index finger and thumb are much more independent and flexible. You can flex the middle joint on the middle finger while mostly extending the ring finger, to sort of make a passable #18 by the scheme in the wiki article. Overall though that binary counting method isn’t all that well aligned with comfortable finger motions. A better one could probably be developed, but it might be a bit more complex. http://www.madsci.org/posts/archives/2005-05/1117326759.An.r.html http://www.madsci.org/posts/archives/2005-05/1117326759.An.r...

e12e 11y ago

If you lock your fist, you can extend your ring finger, then your thumb -- leaving the other three fingers "hanging" in your fist. Will probably be a little painful, and won't be pretty -- but it's (sort-of) possible.

kyberias 11y ago

I can do that with both hands starting from the ring finger's second joint. Right hands is significantly weaker and it kinda hurts to do that.