A study posted by the National Center for Biotechnology Information and published by the Europe PMC founders group investigates natural movements of the right hand in day to day activity. The results were as follows:

-The thumb is the most independent digit, the pointer finger is the most independent finger (meaning it is easiest to move that finger by itself without strain), and the ring finger is the least independent of all (meaning it is difficult to isolate that finger).

-it is always harder to move a finger independently from a directly adjacent finger than it is to move a finger independently from one that is farther away.

[insight: since it is more difficult to move certain fingers by themselves, if i make a design that requires the frequent use of an isolated finger (especially the ring and middle fingers), it will be likely to lead to hand fatigue]

-IDEA: what if i designed a stationary form that used direction force to move the cursor instead of designs that use the movement of fingers to do so. using pressure sensors to dictate the speed of the cursor and programming in a way where the force required to move the cursor is small enough to be usable for long periods, while being large enough to prevent accidental or unwanted movements.

IDEA: what if i created a mouse that could rotate to a neutral position for both hands.

[IMPORTANT INSIGHT: I should then also stay away from designing a form that causes one or two fingers to rest in different positions than the others (the resting position of all fingers should be the same). For example

this picture shows how the resting position of the index and middle fingers are at different heights from the ring and pinky. ]

– Steve Meagher a physiotherapist specializing in ergonomics says that the ulnar nerve and the median nerve both tend to get pinched when your wrist is sat on the edge of a desk while utilizing a mouse. further more, when you physically move the mouse around, you are rubbing and grinding into those two nerves which can cause much discomfort.

(solution is to either position the wrist and arm in a way that is not sitting directly on the base of the wrist, or to provide extra cushioning to decrease the immediate hardness of the desk being used. )

he also says that those particular nerves become aggravated when your wrist is in the extended position for long periods of time)

SOURCES

Ingram, J., Körding,, K., Howard, I., & Wolpert, D. (n.d.). The statistics of natural hand movements. Europe PMC Founders Group.

Meagher, S. (2016, November 10). Gaming- Mouse Position and Wrist Pain. Retrieved November 26, 2020, from https://www.youtube.com/watch?v=1xS7EzEKScs