The Look-At-Me Cellphone Axiom
The amount that a person wants to look like he or she is using a cellphone in a public place — that is, how overt the person is about being on a call — is directly proportional to how advanced the receiver/speaker technology is. For example, people using cellphones in a normal fashion (handset-to-ear) are mostly unconcerned about letting people know that they are using a cellphone. (Though people using cellphones in this way can often be rude they are usually not deliberately so.) In contrast, people who use lavalier microphones are usually loud and demonstrative about the fact that there is no phone at their ear, waving the phone around like a prop to alert passersby to their hands-free-edness. And those with a Bluetooth headset? More theatrical still. Following the slope of wirelessness/overtness, it is fair to assume that when cellphone conversations can be beamed directly to the brain callers will be indistinghuisable from raving lunatics, gesticulating vigorously to let others know that, in fact, they have voices in their heads.