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Filter theory indicates that changes in cochlear filter bandwidths are accompanied by changes in cochlear response latencies. Previous reports indicate that otoacoustic emission (OAE) delays are reduced by exciting medial olivocochlear (MOC) efferents with contralateral broad-band noise (CBBN). These delay reductions are consistent with MOC-induced widening of cochlear filters. We quantified the MOC-induced changes in human cochlear filter-related delays using stimulus-frequency and click-evoked OAEs (SFOAE and CEOAEs), recorded with and without MOC activity elicited by 60dB SPL CBBN. MOC-induced delay changes were measured from the slopes of SFOAE phase functions and from cross-correlation of 500Hz-wide CEOAE frequency-band waveform magnitudes. The delay changes measured from CEOAEs and SFOAEs were statistically indistinguishable. Both showed greater delay reductions at lower frequencies (a 5% decrease in the 0.5-2kHz frequency region). These data indicate that cochlear filters are widened 5% by the MOC activity from moderate-level CBBN. Psychophysically, the large changes in cochlear response latencies, implied by the 0.5ms change in OAE delay at low frequencies, would have a profound effect on binaural localization if they were not balanced in the central nervous system, or by the MOC system producing similar changes in both ears., (Copyright 2010 Elsevier B.V. All rights reserved.)

Reconsultation for lower respiratory tract infection (LRTI) is common in general practice, but those who reconsult rarely have more significant illness warranting antibiotics. Knowledge of factors that predict patient-initiated reconsultation may allow clinicians to address specific issues during the initial consultation that could reduce reconsultations. Thirty-three per cent of a cohort of 431 LRTI patients in a randomised controlled trial reconsulted. Excluding 35 patients with GP-requested reconsultation left 28% (112/396) with a patient-initiated reconsultation during 28-day follow-up. Patient-reported dyspnoea and concerns that persisted after the initial consultation independently predicted patient-initiated reconsultation.