Mehrabian, born in 1939 to an Armenian family in Iran, initially trained as an engineer,[1] but gained renown for his research on the relative importance of verbal and nonverbal communication.
In addition to his scholarly work, Mehrabian developed several psychological assessment tools, including the Arousal Seeking Tendency Scale.
It becomes more likely that the receiver will trust the predominant form of communication, which to Mehrabian's findings is the non-verbal impact of tone+facial expression (38% + 55%), rather than the literal meaning of the words (7%).
The second study dealt with facial expressions (shown in black-and-white photographs) and vocal tone (as heard in a tape recording) and found that the relative contributions of the two communication channels had a ratio of 3:2.
Mehrabian combined the results of these two studies to derive the ratio 7:38:55 for the relative importance of words, tone of voice, and facial expressions in conveying feelings and attitudes.
First, the study is based on the interpretation of the meaning of a single tape of recorded words, which creates a very artificial context.
In contrast, a study in 1992 focused on the communication of happy/sad moods and discovered that hearing words spoken in a "flat" voice was approximately four times more influential than facial expressions seen in a silent film.