Using gated sinusoidal stimuli (tone bursts), frequency-specific auditory brainstem responses (ABR) have been recorded in mice. The gating function represents a filter with a constant narrow bandwidth in the investigated frequency range 2-31.5 kHz. The ABR thresholds found in the CBA/CBA mouse using this technique were in close agreement with those previously reported in the literature concerning mice. The ABR thresholds were analysed in 2-18-month-old animals showing a slight impairment of ABR thresholds with increasing age. The individual variations in ABR thresholds were small.