Vol.7, No 1, 2009 pp. 29 - 45
UDC 81 : 78 81 : 801.654
EVOKED POTENTIAL P300 IN METRICAL COGNITION
– A PILOT STUDY
Mihailo Antović
Department of English, Faculty of Philosophy, University of Niš
In this study we conducted ERP measurement of the P300 evoked potential
in three separate tasks. Five musicians and five nonmusicians listened
to sequences in which a series of short tones of the same frequency was
occasionally interrupted by an octave higher tone. In the first task, with
the tempo of one tone in two seconds, the participants counted the higher
tones; in the second task, they repeated the procedure, where the only
difference was the slower tempo - one tone in three seconds; in the third
task, the tempo was significantly faster - four tones in a second, and
the participants were asked to ignore pitch changes and internally sequence
a 4/4 beat and preserve this patterning until the end of the stimulus (about
4 minutes). Results suggest increased P300 latencies in the second and
the third task, especially in the nondominant and dominant temporal areas,
respectively. In the third task, P300 and P600 were recorded in all musicians,
but in none of the nonmusicians. In addition to the conspicuous difference
between musicians and nonmusicians, this suggests that simultaneous perception
of a number of factors prolongs EP latencies, which may provide some neurophysiological
grounds for constraint-based theories in the cognitive sciences of language
and music, such as Optimality Theory. Additionally, pronounced excitation
of the left temporal lobe may reveal some common neurological resources
for metrical tasks in language and music.
Key words: ERP, P300, meter, language, music
EVOCIRANI POTENCIJAL P300 U METRIČKOJ
KOGNICIJI – PILOT STUDIJA
U ovom radu merili smo evocirani potencijal P300 u tri odvojena zadatka.
Pet muzičara i pet nemuzičara slušalo je sekvence u kojima je niz kratkih
tonova iste frekvencije povremeno prekidan za oktavu višim tonom. U prvom
zadatku, pri tempu od jednog tona u dve sekunde, učesnici su brojali visoke
tonove; u drugom zadatku, ponovili su istu proceduru, osim što je tempo
bio sporiji – jedan ton u tri sekunde; u trećem zadatku, tempo je bio
značajno brži – četiri tona u sekundi, a učesnici su zamoljeni da
ignorišu promene tonskih visina i internalizovano izgrade svest o četvoročetvrtinskom
taktu počev od bilo kog tona koji čuju, te da zadrže ovakav metrički
sklop do kraja draži (oko četiri minuta). Rezultati sugerišu porast
latencije potencijala P300 u drugom i trećem zadatku, naročito, i to
redom, u nedominantnim i dominantnim temporalnim zonama. U trećem zadatku,
potencijali P300 i P600 registrovani su kod muzičara, ali ne i kod nemuzičara.
Uz vrlo primetnu razliku između muzičara i nemuzičara, ovo sugeriše
da istovremena aktivnost većeg broja faktora produžava latencije evociranih
potencijala, što ukazuje na neurofiziološku osnovu teorija baziranih
na ograničenjima u kognitivnim istraživanjima jezika i muzike, poput
teorije optimalnosti. Uz to, izražena ekscitacija levog temporalnog režnja
sugeriše da postoje neki zajednički neurološki resursi pri metričkim
zadacima u jeziku i muzici.
Ključne reči: potencijali povezani sa događajem, P300, metrika,
jezik, muzika
