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The authors refer their results obtained with brainstem-evoked response audiometry (BSERA) and behavioral audiometry in a group of 270 children (aged from 6 months to 12 years) divided into subjects with (group A) and without (group B) reliable audiograms. In group A an agreement between the two methods was found in 77% of cases and a serious discrepancy in 5%. In group B an agreement was found only in 34% of cases, while a serious discrepancy was found in 20% of the children. BSERA was useful because many diagnostic mistakes were avoided. The authors think that BSERA is a reliable technique, as their data show, but in at least 4 cases they found that BSERA gave a hearing level much higher than that obtained with behavioral audiometry or that observed in the children's responses to everyday sounds. Since click gives only partial information of the tonal field and because it is possible to make technical mistakes, the authors believe that BSERA must not be used as the only diagnostic test but that it should be part of a test battery which includes, at least, behavioral audiometry and impedance audiometry.

When two speech messages are presented to normal subjects in a dichotic listening task, the stimuli presented to the right ear are generally reported first and more accurately than signals presented to the left ear. Although a normal Italian speaker produces approximately 100 ms of pre-voicing, we found that the maximum dichotic interference (shown by a slightly larger right-ear advantage and fewer double-correct trials) occurred for stimuli with 30-ms pre-voicing. These data indicate that the duration of pre-voicing is important for intelligibility of Italian stop consonants.

15 normal-hearing, right-handed Italian subjects were tested dichotically with Italian and English stop consonant plus vowel combinations (CVs). The stimuli were modified on a computer-based routine so that the pre-voicing of Italian voiced CVs was 30 ms long. In this condition, a significant right-ear advantage and a consistent lag effect were observed with both Italian and English stimuli. In addition, no significant differences between the two types of stimuli (English and Italian) were observed in the dichotic performances (except when using the 90-ms lag, which resulted in a significant difference in performance).

Air and bone conduction brain stem responses were recorded in 20 adults and 20 infants (16-20 months postconceptional age) with normal hearing. The stimuli were administered using a shielded TDH-39 headphone and a standard B-70A vibrator. Our results show that adults and infants have similar air and bone conduction brain stem thresholds. The comparison of input latency functions obtained with air and bone conduction clicks indicates that the acoustic stimulus generated by the bone vibrator excites more apical regions than that stimulated by the air conduction transient. This is related to the spectrum of the bone conduction click which has an energy peak at 1-2 kHz. Furthermore we found that the difference in latency between adults and infants for air-conducted clicks decreases along with the stimulus intensity and the latencies tend to overlap near the threshold.