What are unshared sensory experiences that occur without external stimuli called?

Unshared sensory experiences that occur without external stimuli are known as hallucinations. Hallucinations involve perceiving things that are not present in the environment, such as hearing voices, seeing things, or feeling sensations without any actual external source causing those perceptions. They can occur in various contexts, including mental health disorders, substance use, or sensory deprivation situations.

Hallucinations differ from other phenomena such as delusions, which are false beliefs that are firmly maintained despite contradictory evidence. Perceptual distortions involve altered perceptions of real external stimuli rather than the perception of nonexistent ones. Sensory overload, on the other hand, occurs when an individual is overwhelmed by excessive sensory input, rather than having a sensory experience that is entirely unshared and disconnected from actual stimuli. Thus, hallucinations are the most accurate term for experiences that happen without any external triggers.