Final answer:
An instructor discussing the levels of responsiveness to sensory impressions is most likely talking about consciousness, which encompasses awareness of internal and external stimuli, our varying states of consciousness, and the theory that much of our mental activity is actually unconscious, as posited by Freud.
Step-by-step explanation:
The instructor is most likely describing consciousness, which refers to our level of awareness about internal and external stimuli. This includes an awareness of sensations such as pain, recognition of our emotions and thoughts, as well as perceiving environmental aspects like light and sounds.
Sigmund Freud's theory states that the conscious mind is analogous to the tip of an iceberg, with the vast majority – our unconscious mind – submerged and hidden from our direct perception. This part of our mind houses repressed memories and desires that influence behavior. Additionally, states of consciousness can vary from full alertness to deep sleep, and also include altered states induced by practices like meditation or the use of substances.