title: Pinna orientation determines the maximal directional sensitivity of bat auditory neurons.
abstract: The auditory response areas of 192 inferior collicular neurons (IC) of Eptesicus fuscus were studied under free field acoustic stimulation. The boundary of the auditory response area of a neuron expands with stimulus intensity (Fig. 1). However, there is a response center within each neuron's response area at which the neuron has the maximal sensitivity. All response centers of the 192 neurons are located within a limited space of the bat's contralateral auditory space. The position of the response center of a neuron changes with different pinna orientations (Figs. 2 and 3) providing a bat with versatility in maximizing the sensitivity of its echolocation system.
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D002685:Chiroptera; D004431:Ear, External / Q000294:innervation*; D004455:Echolocation / Q000502:physiology*; D005072:Evoked Potentials, Auditory; D007245:Inferior Colliculi / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D009949:Orientation / Q000502:physiology*