States of consciousness are a subjective perceptual experience and therefore difficult to define. Some people define the difference between consciousness and unconsciousness by whether the person's eyes are open or shut. According to the Webster Dictionary, consciousness is defined as the quality or state of being aware especially of something within oneself. William James, a key figure in the study of consciousness, believed that consciousness consisted of a steady stream of thoughts, emotions, and perceptions.
consciousness can also be thought of as two separate factors, monitor and control. Monitoring refers to the ability to perceive one's environment, survey potential problems, identify goals and make decisions. Attention (or focusing one's awareness on any thought or outside event) is another word for monitoring.
In contrast, control is one's ability to organize thoughts and utilize behaviors to complete tasks. In other words, monitoring allows a person to survey the environment and make decisions. Control allows that person to act on those decisions.
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