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Phonemic restoration effect is a perceptual phenomenon where under certain conditions, sounds actually missing from a speech signal can be restored by the brain and may appear to be heard. The effect occurs when missing phonemes in an auditory signal are replaced with a masking noise, resulting in the brain filling in absent phonemes. The effect can be so strong that some listeners may not even notice that there are phonemes missing. This effect is commonly observed in a conversation with heavy background noise, making it difficult to properly hear every phoneme being spoken. Different factors can change the strength of the effect, including age and gender. This effect is more important to humans than what was initially thought. Linguists have pointed out that at least the English language is full of false starts and extraneous sounds. The phonemic restoration effect is the brain's way of resolving those imperfections in our speech. Without this effect interfering with our language processing, there would be a greater need for much more accurate speech signals and human speech could require much more precision. For experiments, white noise is necessary because it takes the place of these imperfections in speech. One of the most important factors in language is continuity and in turn intelligibility. ==Background== The phonemic restoration effect was first documented in a 1970 paper by Richard M. Warren entitled "Perceptual Restoration of Missing Speech Sounds". The purpose of the experiment was to give a reason to why in background of extraneous sounds, masked individual phonemes were still comprehensible. :''“The state governors met with their respective legislatures convening in the capital city.”'' In his initial experiments, Warren provided the sentence shown and first replaced the first 's' phoneme in legislatures with extraneous noise, in the form of a cough. In a small group of 20 subjects, 19 did not notice a missing phoneme and one person misidentified the missing phoneme. This indicated that in the absence of a phoneme, the brain filled in the missing phoneme. This indicated that through top-down processing. This was a phenomenon that was somewhat known at the time, but no one was able to pinpoint why it was occurring or had labeled it. He again did the same experiment with the sentence: :'“It was found that the wheel was on the axle.”' He replaced the 'wh' sound in wheel and the same results were found. All people tested wrote down wheel. Warren later did much research for next several decades on the subject. Since Warren, much research has been done to test the various aspects of the effect. These aspects include how many phonemes can be removed, what noise is played in replacement of the phoneme, and how different contexts alter the effect. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Phonemic restoration effect」の詳細全文を読む スポンサード リンク
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