Calibration.

In human speech, the mind must constantly monitor the feedback information from both the speaker's own hearing and the proprioceptive senses which enable the mind to control muscles and create the desired sounds. Thus, the speaker is constantly "calibrating" the feedback to control speech. To change a tense, the speaker may change "run" to "ran," or change the person from "he" to "she," and so on. These "word" changes are achieved by precise control of the muscles used to produce speech.

We "calibrate" our speech frequently as we talk. This is why we can misuse a word, verb tense, or some other part of the initial sentence, and still make corrections in the remaining words of the sentence so that the listener does not hear our mistake.

Thus, in Figure 4, human speech is represented as the interplay between the mind, the mouth, and its related organs (represented in the figure by the tongue), two feedback systems, and conscious calibration as the speaker constructs each sentence. In addition, calibration is continuously taking place within the control center—the mind. However, because it is acting on feedback from hearing and the proprioceptive senses, I am showing calibration as acting on the source of the feedback.

When children learn their mother tongue, their natural ability to hear and mimic adult speech builds complex proprioceptive response patterns. A French-speaking child effortlessly learns to make nasal sounds. An English-speaking child learns to put her tongue between her teeth and make the "th" sound. A Chinese-speaking child learns to mimic the important tones which change the meaning of words. Each of these unique sounds requires learned muscle control within the mouth.

I make no apology for the intricacy of this explanation. The neurological feedback and resulting control of the muscles involved in speech is extremely complex. The mind is involved in a far greater task than simply remembering vocabulary and organizing words into meaningful sentences.