MSO and LSO neurons have opposite optimal interaural phase responses
Evidence
Low-frequency binaural neurons in the MSO are considered maximally activated by IPDs in the range 45–90°, consistent with their reception of excitatory inputs from both ears. High-frequency neurons in the LSO receive excitatory and inhibitory input from the two ears receptively—as such maximum activity occurs when the sounds at the two ears are presented out of phase. — Dijk, Pim van, Physiology, Psychoacoustics and…, 2947
Low-frequency binaural neurons in the MSO and midbrain (inferior colliculus) are maximally activated by IPDs in the range 45–90° (see Grothe et al. 2010 for review). This is consistent with their delay sensitivity being generated by largely excitatory inputs from the two ears. Conversely, those in the LSO appear to be excited by one ear, and inhibited by the other (Grothe et al. 2010 ). Consequently, maximum activity is generated in this (high-frequency) pathway when the sounds at the two ears are out of phase with each other (here, when the signal is switched from 0° to 180°). The IPM-FR, therefore, appears able to distinguish between these two pathways based on the preferred IPDs employed to evoke the response. — Dijk, Pim van, Physiology, Psychoacoustics and…, 2949
Categorization
- DEFINE: The excitatory-excitatory vs. excitatory-inhibitory wiring explains each nucleus’s preferred ITD range.
- XREF: Connects to classic auditory neuroscience knowledge of the MSO coincidence detector (Jeffress model) and LSO as IE neuron. — connects to: Low- and high-frequency binaural brainstem pathways prefer opposite interaural phase ranges; Best-aligned inferior colliculus activation pairs correspond to maximum BIC amplitude. — Dijk, Pim van, Physiology, Psychoacoustics and…, 1451
- SHARE: Worth sending to anyone in auditory neuroscience/bioacoustics: the neat E-E vs. E-I wiring asymmetry that flips peak ITD preference.
- corroborated: 3 independent passages support this claim — Dijk, Pim van, Physiology, Psychoacoustics and…, 2947; Dijk, Pim van, Physiology, Psychoacoustics and…, 2949