[Caleb (OP)]

Situation is this -- we talk to someone on the phone and we are instantly aware they are smiling. The sounds of their pronunciation is clear without any muffling, we can hear the production including the sounds of their voice reflecting off their teeth, etc. (The passages below also indicate that the soft palate is raised and this makes the sound more fluid.)

Being aware that someone is smiling could be very important to us, e.g., in close relationships, in potentially dangerous relationships, etc. Overall I sure would rather deal with someone smiling than someone not smiling. (Maybe similarly dogs dogs also have happy barks, and they sure do have unhappy snarls at times.)

I have thought for a while that analyses of speech sounds might be able detect the vocal qualities of speech produced with a smile. Would be interesting to see how well sounds of a smile correlate with happiness, depression, etc., and also whether changes in voices (due to changes in the smiling responses) are able to measure changes in a person's mood. (Might be useful for suicide hot-lines, psychotherapy, etc.) Psychologist Paul Ekman (see http://www.paulekman.com/wp-content/uploads/2013/07/Physiological-Effects-Of-The-Smile.pdf for some of his interesting research) has long advised people smile to make themselves happier, and psychologist Richard Wiseman suggested people put a pencil between their teeth for 60 seconds or so (without their lips touching the pencil) as a way to make themselves happy.

If people around us are smiling more, we tend to smile more too, everything else being equal. Unconscious imitation, motor neurons, etc.

Any thoughts about the "sounds of a smile"?

Yours,

Caleb

From http://www.dummies.com/how-to/content/improving-your-inflection-on-the-phone.html is this:

"Smiling when you talk on the phone

"One way to positively affect the inflection in your voice is to smile, especially when you first answer the telephone. The reason is not psychological but rather physiological. When you smile, the soft palate at the back of your mouth raises and makes the sound waves more fluid. For those of you who sing in a choir (or in the shower), you know that the wider you open your mouth and the more teeth you show, the better tone you get. The same applies on the telephone. Smiling helps your voice to sound friendly, warm, and receptive.

"Some telemarketing companies are so convinced of the value of smiling when talking on the phone that they install mirrors above telemarketers' desks to remind them to smile. These same people, by the way, call you when you're just sitting down to dinner."

[Tomassci]

The change of voice?