Hearing Sensitivity in the Golden Treefrog Polypedates leucomystax from Vietnam
Poster Number
26
Format
Poster Presentation
Faculty Mentor Name
Marcos Gridi-Papp
Faculty Mentor Department
Biological Sciences
Abstract/Artist Statement
For sound stimuli to be perceived by the brain, they have to transmitted across several structures in the ears. In order to unveil general principles of auditory design, our lab is conducting comparative studies of natural variation in auditory morphology and hearing sensitivity. This study is focused on hearing performance in the South Asian common treefrog (Polypedates leucomystax), as a representative of the family Rachophoridae for which auditory information is very scarce. Auditory responses to pure tones at various frequencies are being quantified with two methods: 1) The vibration of the eardrum is measured with a laser vibrometer, in order to assess the function of the mechanical portions of the ear; and 2) Since frogs cannot be trained to press a button when they hear a sound, we employ neurophysiological recordings to determine which sounds elicit neural responses at the brain. A tungsten electrode is positioned among neurons in the torus semicircularis, an auditory center located in the optic lobe. Sound tones are then played at various intensities and frequencies to stimulate neural response. The data are currently being collected and the preliminary results indicate that the hearing sensitivity of this frog matches closely those of similar-sized treefrogs in the New World, despite their significant geographic and phylogenetic distance.
Location
Grave Covell
Start Date
21-4-2012 10:00 AM
End Date
21-4-2012 12:00 PM
Hearing Sensitivity in the Golden Treefrog Polypedates leucomystax from Vietnam
Grave Covell
For sound stimuli to be perceived by the brain, they have to transmitted across several structures in the ears. In order to unveil general principles of auditory design, our lab is conducting comparative studies of natural variation in auditory morphology and hearing sensitivity. This study is focused on hearing performance in the South Asian common treefrog (Polypedates leucomystax), as a representative of the family Rachophoridae for which auditory information is very scarce. Auditory responses to pure tones at various frequencies are being quantified with two methods: 1) The vibration of the eardrum is measured with a laser vibrometer, in order to assess the function of the mechanical portions of the ear; and 2) Since frogs cannot be trained to press a button when they hear a sound, we employ neurophysiological recordings to determine which sounds elicit neural responses at the brain. A tungsten electrode is positioned among neurons in the torus semicircularis, an auditory center located in the optic lobe. Sound tones are then played at various intensities and frequencies to stimulate neural response. The data are currently being collected and the preliminary results indicate that the hearing sensitivity of this frog matches closely those of similar-sized treefrogs in the New World, despite their significant geographic and phylogenetic distance.