In another related study, Botox patients tested using a fMRI, at Technical University of Munich in Germany, found that in patients which made angry faces, had lower activity in the brain circuits involved in emotional processing and responses. The amygdala, hypothal­amus and parts of the brain stem-as compared with con­trols who had not received treatment.

Interestingly, results from a study published in May 2008 in the Journal of Pain, revealed that when the forearms of 29 participants, had heat applied to them, and were asked to either make unhappy, neutral or relaxed faces during the procedure, those who exhibited negative expressions reported being in more pain than the other two groups.

Findings by psychologist Judith Grob, of the University of Groningen in the Netherlands, suggest that suppressed negativity may transcend into other realms of our life. While performing a series of studies, she asked sub­jects to review disgust provoking images while hiding their emotions or while holding pens in their mouths in such a way that prevented them from frowning. A third group were able to react as they would naturally. As anticipated, her subjects in both groups that did not express their emotions, reported feeling less disgusted afterward than the control subjects. When she gave the subjects a series of cognitive assignments that included fill-in-the-blank exercises, findings suggested those who had repressed their emotions performed poorly on memory tasks and completed the word tasks to produce more negative words-they completed "gr_ss" as "gross" rather than "grass," for instance-as compared with controls.

Grob believes that "People who tend to do this regularly might start to see the world in a more negative light." Grobs conclusions support Darwin's theories, and lends value to what radio announcers have practiced for years, talking with a smile on your face conveys a positive expression in ones voice, and overall presentation quality.