Attention is the process of consciously attending to a thought, activity, or event. We may know what to pay attention to, but it is difficult to pay attention on a consistent basis. Our senses are bombarded with far more information than we could ever hope to process, so most of what is happening around us is "filtered out," and only a small portion of it reaches our conscious mind and is stored in our short-term memory.
The mind is selective about to what it pays attention. The schemas we have stored in our long-term memory determine largely what we notice. They help us unconsciously filter out information deemed irrelevant or unimportant. Therefore, we must have accurate self-defense schemas or the wrong information may be filtered out and ignored.