Circadian differences in the dichotic processing of voicing.
Male and female adult subjects (N = 112) were tested at two times (morning and afternoon) for time-of-day related shifts in linguistic processing on dichotic listening tasks using (1) a divided-attention paradigm for processing digits (0-9) and (2) a focused-attention paradigm for processing consonant-vowel (CV) combinations which were grouped according to the voiced and unvoiced stop consonants. Time-of-day effects were not evident on digits using the divided-attention paradigm. However, on CVs a predicted two-way interaction for Time-of-Day Voicing-due to superior detection of voiced stimuli in the afternoon-was evident. This effect is consistent with a circadian-linked increase in right hemisphere involvement later in the day. Implications for theory, research and educational applications are discussed.
Morton
L L
LL
University of Windsor, Faculty of Education, Ontario, Canada.
Diubaldo
D
D
D000328:Adult; D001288:Attention; D001921:Brain / Q000502:physiology; D002940:Circadian Rhythm; D004007:Dichotic Listening Tests; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010700:Phonetics; D013067:Speech Perception; D014831:Voice