Validation is needed by people who are having covert communication because they may feel a bit uncomfortable with the things that they are discussing. For example, a person would like to show that he does not want the other person to say anything. He would then do a signal with his eyes to alert the other person not to say anything.
Validation works in such a way that the person who received the signal will reciprocate or will show that he has understood the signal quite well. After this, validation can be given further by giving feedback about the whole situation and letting the person know that he is always allowed to state what is on his mind.
Covert communication reflects inner feelings that a person may be uncomfortable talking about. Such communication may be revealed through body language, silence, withdrawn behavior, or crying. Validation is an attempt to confirm the observers perceptions through feedback, interpretation and clarification.