Final answer:
The maximum firing frequency of a primary afferent neuron is determined by its refractory period, which is influenced by the properties of sodium channels on the neuronal membrane. This concept is related to the pitch perception theories, where hair cells on the basilar membrane detect different frequency sounds.
Step-by-step explanation:
The top of a sensory cell's dynamic range can be limited by the firing frequency of the primary afferent neuron. The maximum frequency at which a neuron can fire is set by the refractory period. This is due to the neuronal membrane's sodium channels' properties, which reach a point where a cell cannot fire any faster. Understanding this concept connects to the place theory of pitch perception, wherein different portions of the basilar membrane are sensitive to sounds of different frequencies. Hair cells on the basilar membrane convert the mechanical movement caused by sound waves into neural signals, which are sent to the brain. However, each hair cell can only fire up to a certain frequency due to its refractory period. Higher sound frequencies are coded by hair cells situated closer to the base of the cochlea, while lower frequencies are detected by those towards the apex.