Inverse zombies, anesthesia awareness, and the hard problem of unconsciousness.

Philosophical p-zombies are imagined beings that behave like humans but lack consciousness, used to challenge physicalist theories of mind. Inverting this concept yields i-zombies: beings that appear unconscious but are actually conscious. A real-world approximation of i-zombies exists in anesthesia awareness, where 1-2 per 1000 patients under general anesthesia become conscious during surgery despite appearing unconscious due to paralysis and intubation. Additionally, 22% of patients in a recent study reported dreaming during anesthesia. P-zombies raise the hard problem of explaining qualia; i-zombies pose the practical problem of detecting qualia. The work compares these concepts and examines the hard problem of unconsciousness through anesthesia awareness.

Study at a glance

Abstract

Philosophical (p-) zombies are constructs that possess all of the behavioral features and responses of a sentient human being, yet are not conscious. P-zombies are intimately linked to the hard problem of consciousness and have been invoked as arguments against physicalist approaches. But what if we were to invert the characteristics of p-zombies? Such an inverse (i-) zombie would possess all of the behavioral features and responses of an insensate being, yet would nonetheless be conscious. While p-zombies are logically possible but naturally improbable, an approximation of i-zombies actually exists: individuals experiencing what is referred to as "anesthesia awareness." Patients under general anesthesia may be intubated (preventing speech), paralyzed (preventing movement), and narcotized (minimizing response to nociceptive stimuli). Thus, they appear--and typically are--unconscious. In 1-2 cases/1000, however, patients may be aware of intraoperative events, sometimes without any objective indices. Furthermore, a much higher percentage of patients (22% in a recent study) may have the subjective experience of dreaming during general anesthesia. P-zombies confront us with the hard problem of consciousness--how do we explain the presence of qualia? I-zombies present a more practical problem--how do we detect the presence of qualia? The current investigation compares p-zombies to i-zombies and explores the "hard problem" of unconsciousness with a focus on anesthesia awareness.