Inner voice

Internal monologue, also known as inner voice, internal speech, or verbal stream of consciousness, is thinking in words. It also refers to the semi-constant internal monologue some people have with themselves at a conscious or semi-conscious level (see Default mode network). Much of what people consciously report "thinking about" may be thought of as an internal monologue, or a conversation with oneself. Some of this can be considered as speech rehearsal. A similar term, interior monologue, is used in literary criticism.

When reading, some people's internal monologue moves their muscles slightly as if they were speaking; this is called subvocalizing. In some medical or mental conditions there is uncertainty about the source of internal sentences, and if someone describes hearing an internal monologue this may be an hallucination, or caused by schizophrenia.

In the philosophy of language there is research on internal speech in relation to the building and use of phrases in the creation of a person's own idiom and the importance of language in the process of thinking.

In literary criticism there is a similar term, interior monologue. This, sometimes, is used as a synonym for stream of consciousness: a narrative mode or method that attempts to depict the multitudinous thoughts and feelings which pass through the mind. However, the Oxford Dictionary of Literary Terms suggests, that "they can also be distinguished psychologically and literarily. In a psychological sense, stream of consciousness is the subject‐matter, while interior monologue is the technique for presenting it". And for literature, "while an interior monologue always presents a character's thoughts 'directly', without the apparent intervention of a summarizing and selecting narrator, it does not necessarily mingle them with impressions and perceptions, nor does it necessarily violate the norms of grammar, or logic—but the stream of consciousness technique also does one or both of these things".

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