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Infants' memory for sets of frequencies
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lliFANTS' t£M)RY FUR SETS OF
FR~UENCIES
Annabel J. Cohen University of Tcronto Recent evidence reveals that infants respond to gl obal, attri hrt es of musical sequences such as the pattern of ups and downs (contour) and frequency range. The purpose of the pr-esent, research was to exanine infants' ability to retain specff'Lc infcrmation about, a set of three pitches. Infants were pr esented with random crderi ngs of the three tones of the maja- triad (252, 330, and 392 Hz). Contrasting sequences contaired a set of three notes, each differing fran one of the crigirel tones by one cr two semitones. Infants can solve such a task only if they are able to retain precise infcnnation about the frequency of the set of tones, in which case a sequence with new tones would be per cedved to differ. If infants encode and retai n only the contour of the crigiral sequence, then they wcold be tnabl e to perf'orm the task since the contour of standard and contrasting sequences woold provide irrelevant infcnnation. Tones were 200 msec in duration willi 200-msec intertone intervals. After the infant reached a trai ning criterion of four consecutive correct r esponse s, the test trials began: 15 change trials and 15 no-change trials, in quasi-random crder. The subjects were 15, full-term infants fran 8 to 11 months of age. Mean .,d', calculated fran the Iro~rtion of headturns on change and no-change trials, was significantly greater than 0.0, indicating discrimiretion of the contrasting frequency set fran the baokgrcmd frequency set. Thus, infants can categorize sequences on the bast s of frequency alone. These findings extend earlier evidence of infants' ability to retain contour.
lliFANTS' t£M)RY FUR SETS OF
FR~UENCIES
Annabel J. Cohen University of Tcronto Recent evidence reveals that infants respond to gl obal, attri hrt es of musical sequences such as the pattern of ups and downs (contour) and frequency range. The purpose of the pr-esent, research was to exanine infants' ability to retain specff'Lc infcrmation about, a set of three pitches. Infants were pr esented with random crderi ngs of the three tones of the maja- triad (252, 330, and 392 Hz). Contrasting sequences contaired a set of three notes, each differing fran one of the crigirel tones by one cr two semitones. Infants can solve such a task only if they are able to retain precise infcnnation about the frequency of the set of tones, in which case a sequence with new tones would be per cedved to differ. If infants encode and retai n only the contour of the crigiral sequence, then they wcold be tnabl e to perf'orm the task since the contour of standard and contrasting sequences woold provide irrelevant infcnnation. Tones were 200 msec in duration willi 200-msec intertone intervals. After the infant reached a trai ning criterion of four consecutive correct r esponse s, the test trials began: 15 change trials and 15 no-change trials, in quasi-random crder. The subjects were 15, full-term infants fran 8 to 11 months of age. Mean .,d', calculated fran the Iro~rtion of headturns on change and no-change trials, was significantly greater than 0.0, indicating discrimiretion of the contrasting frequency set fran the baokgrcmd frequency set. Thus, infants can categorize sequences on the bast s of frequency alone. These findings extend earlier evidence of infants' ability to retain contour.