Brainstorm

Person --> Object <-- Person

Person <-- Object --> Person

Person <== Object ==> Person

Person _<== Object ==^> Person

Person -- Object --> Person

[Person] -- Object --> Person

[Person] <-- Object -- Person

Person <--> Object <--> Person

                /----->
Person --/ Object /-- Person
                   <----/

Obj[Person]ect <--> Obj[Person]ect

Person ⊃ Object ⊂ Person

Person --> [Object] <-- Person

Person/Object <--> Person

Person/Object <-- Person

Person/Object --------------> Person

Person/Object] ? <-- Person

Person ? Object ? Person

"Confusion machines" yielding results for the tested not the tester

Belgian/German artist Carsten Höller doesn't make relational prosthetics in the strictest definition of the term (although the concept of "influential environments is certainly getting close) but I liked some of the language in this review of his career survey at the New Museum:

Slim and balding, he could still easily pass for the agricultural entomologist he once was. Except that now his deeply inquisitive, German-accented musings refer not to cereal aphids but to the humans who consent to participate in his thoroughly subjective experiments, which stand science on its head, yielding results for the sake of the test subject rather than that of the tester.

The devices and environments Mr. Höller has conceived since he began to make art 18 years ago — he prefers to think of them not as art objects but as “confusion machines” — require a great deal more planning and money than conventional lab equipment.

An Intimate Transaction, Between Two People With No History and No Future

Sarah Zarr in her short essay, "Something for the Pain," about her trip to the physiotherapist's office:

"The claustrophobic space, and us so close in it, made me want to giggle or crack a joke.  But I remained dignified and managed to act like people ask to touch my hips every day."

and