Abscesses occur when an area of tissue becomes infected and the body's immune system tries to fight it. White blood cells move through the walls of the blood vessels into the area of the infection and collect within the damaged tissue. During this process, pus forms.
cognition cogÂ·niÂ·tion (kÅg-nÄ­sh'Én) n. The mental faculty of knowing, which includes perceiving, recognizing, conceiving, judging, reasoning, and imagining.
Cognitive processes or cognitions refer to a range of processes within the individual that has varying degrees of effect on the persons behavior. Included are perceptions; beliefs; thoughts; images; and systems of processing, coding, and retrieving information.