Research in the Laboratory of Comparative Psychoacoustics is aimed at understanding how animals communicate with one another using sound and whether there are parallels with how humans communicate with one another using speech and language. Birds such as songbirds and parrots, like humans, rely on hearing and learning to develop a normal vocal repertoire. We often study budgerigars (parakeets), canaries, zebra finches, and other small birds. For instance, we have specific projects on vocal learning and vocal development in budgerigars, the regeneration of auditory hair cells and recovery of hearing and the vocalizations in small birds following hearing damage, and the effect of noise on hearing. Other studies focus on how small birds localize sounds, how they perceive complex sounds such as bird vocalizations and human speech, and how the bird ear functions.