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Inner speech is close to uttered speech | Neuro-patch
There has recently been a paper in eLife by Whitford etal, Neurophysiological evidence of efference copies to inner speech, Dec 2017 doi 10.7554/eLife.28197.001, examining inner speech. They find it very similar to overt speech. When we speak a series of motor commands are prepared and executed by the mouth, throat and vocal cords. Copies of these commands, called efferemce copies are used to predict what the auditory area will hear. This prediction is called the internal forward model. When incoming sounds match the prediction, the auditory area lowers its response to the speech. This efference copy mechanism applies to other motor commands and is why we cannot tickle ourselves. The sensory pattern that will result from an action is predicted so that self-generated sensory input is attenuated compared to input that is not self-generated. In the case of speech, the actual sounds are predicted and when input arrives at the right time that matches the expected sound, the sound is