When an “emotional expression (such as scowling) adds new information to the verbal message it can affect the persuasiveness of the overall message and thereby credibility,” University of Haifa researcher S. Hareli said.
I wonder how cultural background influences such judgments. I reject emotional expressions as covering up inadequate information, a sort of con-job. And, yes, that’s cultural and academic research background influenced.
Hareli, S., Harush, R., Suleiman, R., Cossette, M., Bergeron, S., Lavoie, V., Dugay, G., & Hess, U. (2009). When scowling may be a good thing: The influence of anger expressions on credibility. European Journal of Social Psychology, 39 (4), 631-638.