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parallels cortical physiological findings of a larger mismatch response to changes in the upper note of a polyphonic
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Enhancement to music II, Linguistic transfer I: Cello and speech. Musacchia et al 2007.52 Musicians show enhanced pro- cessing to speech, not just music. In a design that tested musicians’ responses to both music and speech, more evi- dence of selective enhancement in musicians’ subcortical processing emerged. Two stimuli, a bowed cello note and a “da,” revealed a musician enhancement. Musicians’ phase- locked responses to the fundamental frequencies of both stimuli were enhanced and the extent of enhancement corre- lated with years of musical practice. This evidence of superi- or processing in the brainstem in musicians was the first indication of transfer to the speech domain. This study also investigated visual contributions to brainstem auditory pro- cessing because of musicians’ known ability to better process
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musicians, along with faster timing for an onset peak occur- ring at about 12 ms (Fig. 5). Thus processing of both music and speech and audiovisual interaction in the auditory brain- stem appears to benefit from musical experience.
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A second finding is that the combination-tone responses, absent in the stimuli, also were enhanced in musi- cians, providing evidence that these responses probably are of a central origin, and not a result of cochlear non-linearities propagated up to the midbrain.
melody.
Here, the two auditory stimuli were presented along with videos of the cello being bowed and a man speaking the syllable. In this presentation mode, similar phase-locking enhancements were seen in
Linguistic transfer II, Tonal languages. Wong et al., 2007. In tonal languages, a single phonetic combination, like “ma,” has various meanings depending on the inflection with which it is spoken. In Mandarin, “ma” spoken with a high, level pitch, means “mother.” Spoken with a dipping (down then up) pitch, it means “horse.” Two other inflections, falling and rising, produce two additional words and these four tones round out the Mandarin repertoire. Other languages have even more tonal markers. It has been demonstrated that pitch-tracking to Mandarin words by the auditory brainstem is more accurate in native Mandarin speakers,49 likely due to years of tuning engendered by the importance of pitch to their native language. We were interested to see if pitch track- ing to Mandarin syllables is improved in individuals whose auditory systems were tuned to pitch for non-linguistic rea- sons. Non-tonal-language-speaking musicians were chosen for this investigation. Pitch, for musicians, is a critical dimen- sion of their art, and both their auditory systems and their cognitive centers have been extensively honed to it. Brainstem responses to the syllable “mi” with high-level, ris- ing and dipping tones were measured. Accuracy of pitch
dual-domain audiovisual stimuli.
Fig. 4. Musicians have enhanced brainstem representation of the harmonics of the higher note in a chord. No encoding differences were seen at response frequencies corre-
sponding to the two notes comprising the chord (G and E, labeled with musical notes). However, musicians have enhanced encoding at integer harmonics of the higher note
(black arrows). Certain combination tones (not present in the chord) also are also more strongly represented in the musician response (gray arrows). Modified from Lee et
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al., 2009.
Fig. 5. Whether a “da” is heard by itself or with an accompanying video of its speaker uttering it, the evoked brainstem response is larger in musicians (red). This was the
first evidence of linguistic transfer of the musician advantage. Modified from Musacchia et al., 2007.
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Musician’s Auditory World 19