Development of auditory perception
Onset of hearing
• Week 28 in gestation:
– Evidence from preterm infants
– Auditory stimuli elicit responses
• Changes in heart rate
• Eyeblinks
• Gross motor responses
• Auditory brain stem responses
– Evidence for preferred sounds in newborns
• preferential listening and sucking rates
• Newborns can discriminate sounds
• Suggests auditory learning in utero
Infant auditory preferences
– Newborns prefer mothers' voices to unfamiliar voices
• Sucking rates differ to sound of mothers than other voice
» DeCasper & Fifer (1980) Science
– Evidence that sounds are retained from uterus to perinatal period
• Newborns prefer low-pass filtered version of mothers voice than unfiltered version
– Fifer & Moon, (1985)
Infant auditory preferences
– Newborns prefer familiar story read aloud repeatedly during final weeks of
pregnancy than novel story
– DeCasper & Spence (1986)
– Two-day-olds prefer their native than unfamiliar language.
– Mehler et al. (1988)
– Moon, C., Cooper, R.P. & Fifer, W.P. (1993). Infant Behavior and Development, 16, 495–500.
– Evidence that newborns have extracted prosodic features from auditory input
during last few weeks of prenatal development
Auditory preference not acquired in utero
• Newborns from all language backgrounds prefer to listen to infant-directed (‘motherese’) than
adult-directed speech
– Slow speaking rate
– Small number of words
– Large pitch excursions
• Cooper & Aslin, 1990
– Children with autism do not show this preference
• Kuhl et al. (2005)
• Infants prefer hyperarticulated over normally articulated infant-directed speech
• Cooper & Cooper, (1999)
• Infant directed speech not heard in utero
• Some acoustic patterns intrinsically preferred by newborns
Measuring neural development of audition
Neural development of auditory system
• Auditory capabilities at birth suggests well developed system at birth