Spectrotemporal alterations and syllable stereotypy in the vocalizations of mouse genetic models of speech-language disorders

Specific language impairment (SLI) and developmental dyslexia (DD) are common speech-language disorders exhibiting a range of phonological and speech motor deficits. Recently, mouse genetic models of SLI (Foxp2) and DD (Dcdc2) have been developed and promise to be powerful tools in understanding the biological basis of these diseases. Surprisingly, no studies of the adult vocalizations—which exhibit the most elaborate and complex call structure—have been performed in these mouse strains. Here, we analyze the male ultrasonic courtship song of Dcdc2 knockout mice and Foxp2 heterozygous knockout mice and compare it to the song of their C57BL/6J background littermates. Preliminary analysis indicates considerable difference between the three groups. For example, Foxp2 heterozygous knockout song contains less frequency modulation and has a reduced syllable inventory in comparison to that of wildtype littermates. The call production and phonological deficits exhibited by these mouse models are reminiscent of the symptoms observed in humans with these disorders.