Middle Age, a Key Time Point for Changes in Birdsong and Human Voice

Voice changes caused by natural aging and neurodegenerative diseases are prevalent in the aging population and diminish quality of life. Most treatments involve behavioral interventions that target the larynx because of a limited understanding of central brain mechanisms. The songbird offers a unique entry point into studying age-related changes in vocalizations because of a well-characterized neural circuitry for song that shares homology to human vocal control areas. Previously we established a translational dictionary for evaluating acoustic features of birdsong in the context of human voice measurements. In the present study. we conduct extensive analyses of birdsongs from young, middle-aged, and old male zebra finches. Our findings show that birdsongs become louder with age, and changes in periodic energy occur at middle age but are transient; songs appear to stabilize in old birds. Furthermore, faster songs are detected in finches at middle age compared with young and old finches. Vocal disorders in humans emerge at middle age, but the underlying brain pathologies are not well identified. The current findings will motivate future investigations using the songbird model to identify possible brain mechanisms involved in human vocal disorders of aging.