The following slide shows an illustration from my book The Recycling Occupational Therapist. It also shows my son demonstrating how to push the button switch embedded in the handle covered with red contact paper.
Many of my clients- adults with developmental disabilities had goals to isolate their index finger and use it functionally. I found that they enjoyed pressing a button music switch that activated music. I attached the switch to a handle cut from a plastic detergent bottle to encourage grasping with one hand while activating the switch with the other hand. This worked especially well with clients with hemiplegia.
When do babies develop finger isolation skills?
The following is an excerpt from my book From Rattles to Writing: A Parent’s Guide to Hand Skills:
Finger Isolation means the separate or independent movement of fingers
to perform manipulations. Your twelve-month-old baby isolated the index
finger mainly to poke and point. In Chapter 3 you read about toys, such as
pianos and telephones, that help children isolate the index finger. Your younger
baby also learned how to use the index finger and thumb together to pick up
tiny objects. Now your older child will use the index and middle fingers and
thumb to perform more complex tasks, such as turning the pages of a book
one at a time.
FINGER ISOLATION TO POKE, POINT, AND PUSH BUTTONS
At about the same time your baby is perfecting her pincer grasp to find
every crumb on the floor (you thought had been swept), she is also learning
to isolate the index finger to poke and push buttons with that highly talented
pointer finger. Between twelve and sixteen months of age, she will show off
her finger isolation abilities by pointing to everyone and everything.
Finger Isolation means the separate or independent movement of fingers to perform manipulations.