The higher-order theory (HOT) of consciousness is often misunderstood. This theoretical paper clarifies HOT's position, distinguishing it from global workspace theory and early sensory models. Critics have accused HOT of overintellectualizing consciousness, but the authors argue that the cognitive requirements for higher-order states are considerably less than often presumed, positioning HOT as intermediate between other views. Most HOT proponents do not equate consciousness with metacognition or confidence. Compared to other theories, HOT can better account for complex everyday experiences like emotions and episodic memories, making it useful for conceptualizing pathological mental states.
Direct pharmacological stimulation of the prefrontal cortex (PFC) restores wakefulness in anesthetized rats, providing causal evidence that the PFC plays a key role in conscious experience. This finding helps resolve debates about the region's importance, as prior evidence was largely correlational.
The word 'consciousness' conflates two distinct types of brain computations: C1, which selects information for global broadcasting and flexible use, and C2, which self-monitors computations to produce a subjective sense of certainty or error. Current machines, despite recent successes, mostly implement computations akin to unconscious processing (C0) in humans. The authors review psychological and neural science of unconscious and conscious computations and outline how these may inspire novel machine architectures.