auditory hallucination

A hallucination is a perception in the absence of a stimulus that is believed to be genuine, ie. the subject experiences an imaginary stimulus as being real. A pseudohallucination is similar to an hallucination in all respects except that of absolute belief in the authenticity of the stimulus. In an illusory experience, a genuine sensation is attributed to an incorrect cause (eg. misinterpreting a coat hanging on a door to be an intruder). A delusional perception is where a genuine perception (ie. correctly sensed and interpreted) is given some additional (and typically bizarre) significance. Hallucinations may occur in any sensory modality—visual, auditory, olfactory, gustatory, tactile, proprioceptive, equilibrioceptive, nociceptive, thermoceptive.
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Hallucination /hal·lu·ci·na·tion/ a sense perception that has no basis in external stimulation.hallu´cinativehallu´cinatory haptic hallucination [more]Auditory hallucination - Community and Resources

Noun
1. illusory auditory perception of strange nonverbal sounds
(synonym) acousma
(hypernym) hallucination