Show Tag: mso

Select Other Tags

LSO, MSO, and DCN converge in the central nucleus of the IC (ICC).

In mammals, different neurons in the medial superior olive (MSO) are tuned to different ITDs.

The model of biological computation of ITDs proposed by Jeffress extracts ITDs by means of delay lines and coincidence detecting neurons:

The peaks of the sound pressure at each ear lead, via a semi-mechanical process, to peaks in the activity of certain auditory nerve fibers. Those fibers connect to coincidence-detecting neurons. Different delays in connections from the two ears lead to coincidence for different ITDs, thus making these coincidence-detecting neurons selective for different angles to the sound source.

The granularity of representations of ITDs and ILDs in MSO and LSO reflects the fact that ITD and ILD are most useful for auditory localization in different frequency ranges: ITDs for high frequencies are less densely represented in MSO and ITDS are less densely represented in LSO.

Liu et al. model the LSO and MSO as well as the integrating inferior colliculus.

Their system can localize sounds with a spatial resolution of 30 degrees.

Liu et al.'s model of the IC includes a Jeffress-type model of the MSO.

Jeffress' model has been extremely successful, although neurophysiological evidence is scarce (because the MSO apparently is hard to study).

Jeffress' model predicts a spatial map of ITDs in the MSO.

Jeffress' model predicts a spatial map of ITDs in the MSO. Recent evidence seems to suggest that this map indeed exists.

Rucci et al.'s system comprises artificial neural populations modeling MSO (aka. the nucleus laminaris), the central nucleus of the inferior colliculus (ICc), the external nucleus of the inferior colliculus (ICx), the retina, and the superior colliculus (SC, aka. the optic tectum). The population modeling the SC is split into a sensory and a motor subpopulation.

In Rucci et al.'s system, the MSO is modeled by computing Fourier transforms for each of the auditory signals. The activity of the MSO neurons is then determined by their individual preferred frequency and ITD and computed directly from the Fourier-transformed data.

Recent neurophysiological evidence seems to contradict the details of Jeffress' model.