Hair Cells: Tricks to enhance response:
• To enhance frequency tuning:
– Mechanical resonance of hair bundles: Like a tuning fork, hair
bundles near base of cochlea are short and stiff, vibrating at high
frequencies; hair bundles near the tip of the cochlea are long and
floppy, vibrating at low frequencies.
– Electrical resonance of cell membrane potential
• Synaptic transmission speed:
– Synaptic density: for speed ?
• Adapting to large displacement:
– Ca2+-driven shift in tip link insertion site, myosin motor on actin in
hair bundles.
PNS Fig 31-5