conscious

Meaning: To be conscious is to be aware of yourself and your environment and able to respond to them. Consciousness is not an on-off switch. It varies across states: alertness, relaxed or drowsy wakefulness, the stages of sleep, and altered states such as hypnosis, meditation and the effects of psychoactive drugs. Attention controls what enters awareness; selective attention lets some stimuli in while others stay outside it.

In Freud's topographic model, the conscious holds the thoughts and perceptions you are aware of at this moment. The preconscious holds material you are not thinking about now but can recall with little effort. The unconscious holds material, such as repressed wishes and conflicts, that is not readily accessible to awareness.

On the MCAT: Passages may give EEG patterns (for example beta waves in alert wakefulness, alpha waves in relaxed wakefulness) and ask which state of consciousness fits. Other questions ask you to classify a thought or memory as conscious, preconscious or unconscious, or to link attention to what reaches awareness.

Common confusion: Students equate unconscious with knocked out or asleep. In Freud's model, unconscious means outside awareness yet still influencing behavior. The preconscious is not unconscious, because its contents can be brought into awareness easily.