BACKGROUND Asymmetric reduction of the P3 event-related potential (ERP) has provided evidence of left temporal lobe dysfunction in schizophrenia. Prior studies have been limited by reliance on simple target detection (oddball) tasks with pure tones. This study investigated the time course and topography of ERPs to binaural syllables or complex tones in dichotic listening tasks. METHODS Event-...

Binaural sensitivity is an important contributor to the ability to understand speech in adverse acoustical environments such as restaurants and other social gatherings. The ability to accurately report on binaural percepts is not commonly measured, however, as extensive training is required before reliable measures can be obtained. Here, we investigated the use of auditory evoked potentials (AE...

Interaural time difference (ITD; the delay between arrival of sound at the 2 ears) is one of the primary cues for localization of sound in the azimuthal (left-right) dimension. Its use, however, is limited to tone frequencies below 1,500 Hz in part due to the ambiguity of leading and lagging high-frequency waveforms and the reduced ability of peripheral auditory neurons to phase-lock at high fr...

Under binaural listening conditions, the detection of target signals within background masking noise is substantially improved when the interaural phase of the target differs from that of the masker. Neural correlates of this binaural masking level difference (BMLD) have been observed in the inferior colliculus and temporal cortex, but it is not known whether degeneration of the inferior collic...

Introduction Release from masking, or the masking level difference (MLD), is a phenomenon in which the binaural auditory system can take advantage of interaural phase differences to improve the detection of signals in a background of noise. The MLDphenomenon can be observed for both tonal and speech signals at or near threshold levels. Similarly, intelligibility of speech presented at suprathre...

Binaural pitch fusion is the fusion of dichotically presented tones that evoke different pitches between the ears. In normal-hearing (NH) listeners, the frequency range over which binaural pitch fusion occurs is usually <0.2 octaves. Recently, broad fusion ranges of 1-4 octaves were demonstrated in bimodal cochlear implant users. In the current study, it was hypothesized that hearing aid (HA) u...

Forward-masked intensity discrimination was measured as a function of level in experiments designed to reveal insights into the mechanism(s) underlying the midlevel elevation of the Weber fraction. The standard and maskers were 1.0-kHz tones that were separated by 100 ms. Performance was measured for listeners with normal hearing using an adaptive procedure. In experiment 1, intensity discrimin...

The combined selectivity for amplitude modulation frequency (AMF) and interaural time difference (ITD) was investigated for single units in the auditory midbrain of the grassfrog. Stimuli were presented by means of a closed sound system. A large number of units was found to be selective for AMF (95%) or ITD (85%) and mostly, these selectivities were intricately coupled. At zero ITD most units s...