Stimulus, Response, and Observer Variables in the Auditory Screening of Newborn Infants

Abstract

Behavioral responses of 144 healthy neonates to actual and simulated presentations of three different high-frequency sounds of 85 dB SPL were studied. Stimuli were a narrow-band noise centered at 2000 Hz, a narrow-band noise centered at 3150 Hz, and a pure tone increasing and decreasing in frequency between 2000 and 4000 Hz. A masking noise which prevented knowledge of stimulus events was presented to one member of each observer pair. Results indicated that an observer’s judgments of infant behavior may be significantly influenced by knowledge of stimulus events. More responses were observed with the narrow-band noise centered at 2000 Hz; the most frequently observed responses were strong whole-body movements. A decrement in response strength tended to occur with repeated stimulation. Neither positive nor false positive responses were related to sex, anomalies, gestation period, birth weight, age at test, or body temperature. The inherent complexities of infant screening are discussed in relation to a signal detection paradigm.