Intelligibility of sentences recorded from the uterus of a pregnant ewe and from the fetal inner ear.

The intelligibility of sentences recorded from the uterus of a pregnant ewe and from the near-term fetal sheep inner ear was judged by 30 listeners. Sentences were presented to the ewe at 95 and 105 dB SPL while sequential recordings of sound with a hydrophone and a cochlear microphonic (CM) with electrodes were made. Recordings were randomized and presented to listeners to judge the intelligibility of sentences processed through the ewe and fetal inner ear.

Fetal central auditory system metabolic response to cochlear implant stimulation.

Objectives: The purpose of this study was to examine the effects of profound auditory deprivation and its treatment by cochlear implantation and stimulation on the metabolic activity of the central auditory system in fetal sheep.

Methods: Six ovine fetuses at 85% to 90% gestation were bilaterally deafened by kanamycin perfusion and unilaterally implanted with cochlear electrode arrays. Half of the implanted animals were stimulated with an extrauterine sound processor, and half were not.