In selective attention, we quickly pick up cues from our environment to be interpreted. When that environment is unfamiliar, we tend to pay closer attention to salient cues that match our own, (for example, same age group), cues distinctive from the group (for example, different skin color), and cues that serve our expectations or goals for the interaction (for example, handshake greeting ritual). In a world with too much input to process individually, people are drawn to a distinctive feature of another person, and make links with the setting. This can be the beginnings of racist treatment.
In the second step of perception, the selective organization and labeling, our culture and language give us guidance for organizing aspects of our environment that we consider relevant. Our socialization has taught us to categorize similar things together and label them with a symbol or name. The name you choose for your perceptual organization depends on your identities, values, attitudes, language labels and the context. We also tend to fill in missing information to make sense of a particular situation. If you see an older woman pushing a baby stroller, you may assume she is the child's grandmother. If we are making these guesses within our own cultural community, we may be more or less accurate. However, when we fill in these blanks in unfamiliar cultures, we have a greater chance of being completely wrong.
After selective attention, selective organization, and labeling, we come to selective interpretation. In this step, we attach meaning to our received data, which includes our expectations. Expectations are essentially what we anticipate and predict in the communication behaviors of others during an interaction, and they act as filters as we perceive others. We each have certain expectations of certain situations, and when someone violates those, we may become surprised, emotionally aroused, and pay more attention to this person's odd behavior.
Taken together, these three perceptual filters provide major barriers to effective intercultural communication. When we assume that we perceive and interpret the behaviors of other cultural groups in an unbiased manner, we are leading to ineffective communication. Rather than being objective, we are actually highly subjective, selective, and biased in our perceptions of others. However, becoming mindful of these tendencies can go a long way toward helping us "catch ourselves" more often and choose flexible communication instead.