The Power of the Unsaid – How to Use Nonverbals to Affect Perception
Christopher Philip

We understand the power of nonverbals, but which channel is actually more important; verbal or nonverbal?

To test the relative strength of nonverbals, researcher led by Luigi Castelli, University of Padova, Italy produced two videos, one with positive body language and one with negative body language, all else equal, to dissect just how powerful nonverbals are in the formation of impressions.

Two videos were created for the purpose of observation. In the first video, a white and black actor were depicted in an interaction. In both videos, the black actor introduced himself by saying his name and then shook the hand of the white actor. He then remained seated listening to the white actor without making any movement.

However, the white actor was varied across each video in terms of nonverbals. In the positive condition, the white actor shook the black actors hand vigorously, had a vigorous tone of voice, sat close to him, had a forward inclination of the body, and often established eye contact with the black actor. In the negative condition, the white actor shook the black actors hand loosely, had a slow and hesitant tone of voice, kept an
empty seat between himself and the black actor and had a backward inclination of the
body, and avoided eye contact.

The verbal behaviour in both conditions showed that the white actor had very positive evaluations for the black actor.

The videos were then showed to subjects after which they were asked to formulate their impressions of the black actor.

Results showed that the negative nonverbals was enough to harm the impression of the black actor in a significant way. Results also showed that participants would personally behave more coldly toward the black actor, but only in the negative nonverbal condition. Subjects also found that the white and black actor were “more at ease” in the positive nonverbal condition, rather than the negative nonverbal condition. When the white actor behaved more positively during the interaction, the black actor was rated at more friendly by the subjects.

In the second study nonverbals were tested on the ability to influence perceptions in a negative or positive way once-more. This time, however, the confederate read a particularly negative alleged journal report on Black criminal involvement. In one condition, the confederate depicted positive behaviour to the subject by nodding, smiling and a forward incline. In the other condition, nonverbal behaviour remained neutral. The researchers hypothesized that the subjects would show more negative attitudes when body language was positive, rather than neutral suggesting that the subjects would form an in-group and empathize more with the confederate.
The results from the second study confirmed those of the first. Nonverbal behaviours during the interaction affected the participants’ implicit attitudes toward the Black “out-group.” In other words, when the confederate used positive nonverbal behaviours such as smiling, nodding and leaning forward when discussing Black people, the subject tended to adopt the negative attitude about Black people.

Results of the study indicate that nonverbal behaviours are perceived by onlookers at some level, subconscious or otherwise. They are also effective in transferring impressions to onlookers. The results also show that nonverbal channels are often more powerful than verbal channels. Because of this, when one wishes to control a message, one should pay attention to the accompanying nonverbals and not just the verbal information transmitted.


Castelli, Luigi; Luciana Carraro; Giulia Pavan; Elisa Murelli, and Alessia Carraro. The Power of the Unsaid: The Influence of Nonverbal Cues on Implicit Attitudes. Journal of Applied Social Psychology. 2012. 42(6): 1376–1393.