Gap detection in infants, children, and adults
S E Trehub1, B A Schneider, J L Henderson
1University of Toronto, Mississauga, Ontario, Canada.
Insights
Infants and children can detect brief gaps in sound, with performance improving with age. This study refined gap-detection thresholds in young listeners using Gaussian-enveloped tone pips.
Area of Science:
- Auditory Neuroscience
- Developmental Psychology
- Psychoacoustics
Background:
- Auditory development in infants and children is crucial for language acquisition.
- Gap detection, the ability to perceive brief silent intervals in sound, is a fundamental auditory skill.
- Previous research indicates significant age-related differences in auditory gap detection.
Purpose of the Study:
- To investigate age-related differences in auditory gap detection thresholds.
- To determine the gap-detection abilities of infants (6.5 and 12 months), children (5 years), and adults.
- To assess the impact of Gaussian-enveloped tone pips on gap detection performance.
Main Methods:
- Participants (6.5-month-olds, 12-month-olds, 5-year-olds, adults) discriminated tone pips with varying gap durations.
- A two-alternative forced-choice procedure was used to measure performance.
- Gap-detection thresholds were estimated using a d' = 0.5 criterion.
Main Results:
- 6.5-month-olds performed above chance on most gap durations (except 8 ms); 12-month-olds performed above chance on all tested durations.
- 5-year-olds and adults also exceeded chance levels across all tested gap durations.
- Adults outperformed 5-year-olds on 12 ms and 16 ms gaps; thresholds were 11 ms (infants), 5.6 ms (children), and 5.2 ms (adults).
Conclusions:
- Auditory gap detection is present in infants as young as 6.5 months and improves with age.
- The use of Gaussian-enveloped tone pips may reduce age-related differences compared to previous studies.
- Findings contribute to understanding auditory development and the maturation of temporal processing.
Abstract:
Listeners who were 6.5 months, 12 months, 5 years, and 21 years of age were required to discriminate a pair of 500-Hz, Gaussian-enveloped tone pips from a short 500-Hz tone of the same duration and total energy. Groups of 6.5-month-old infants were tested on a single gap duration: 8, 12, 16, 20, 28, or 40 ms. Groups of 12-month-olds were also tested on a single gap duration: 8, 12, 16, or 20 ms. The 5-year-old children and adults were tested on gap durations of 8, 12, and 16 ms. The mean performance of 6.5-month-olds significantly exceeded chance levels on all gap durations except 8 ms, and that of 12-month-olds was above chance levels on all gap durations. For 5-year-old children and adults, mean performance also exceeded chance levels for all gap durations tested. Adults performed significantly better than 5-year-old children on gap durations of 12 and 16 ms. Gap-detection thresholds, defined by a performance criterion of d' = 0.5, were estimated at 11, 5.6, and 5.2 ms for infants, children, and adults, respectively. It is likely that smaller adult-infant differences in the present study compared to those reported in previous research stem from our use of Gaussian-enveloped tone pips and the consequent minimization of adaptation effects.
