Talk:Jeffress model

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    The "Jeffress model" entry is an informative, succinct, and balanced account of this classic model. What I particularly enjoyed are the quite extensive conceptual links that are made to other temporal correlation models (auditory and nonauditory). One may disagree with the statement that "neuroanatomy and neurophysiology has largely confirmed the basic premises of the basic model". However, the text acknowledges the ongoing debate regarding actual neuronal implementation and provides references to it. Moreover, biological plausibility (or lack thereof) does not affect the conceptual, neurocomputational virtues of Jeffress' model.

    The text could be improved in a couple of places.

    The statement that there "may" be skewing of best interaural delays to sounds on one side (with the reference to Campbell and King 2004) is really a vast understatement. The contralateral bias of this distribution is a consistent finding in virtually all reports of neurons sensitive to interaural time differences, at different anatomical levels and in different species.

    Another inaccuracy regards the statement that spherical cells "produce trains of action potentials that replicate the input spike trains almost on a spike-by-spike basis as well as preserving spike timing". It appears that the output spike trains of these cells differs quite substantially from their inputs, in a way that make spike times more reliable markers for azimuthal position.

    Figure 3 just shows a grid "interaural time difference" vs. "frequency": something appears to be missing from this figure. Also, I think the x-label is misleading and should be "neural delay" or "internal delay" or "matching delay" rather than interaural time difference, which is the stimulus variable that is mapped by virtue of the range of neural delays. The figures could be made more tutorial by actually showing peaks of neural excitation in Figs. 1 or 2: was that perhaps intended for Fig. 3?

    I find the comments (both in the main text and in note 2) on the loci where Jeffress put his network misleading in their phrasing. This is of little importance scientifically, but Jeffress' 1948 comments, combined with his "disavowal" 10 years later (Jeffress, JASA 1958), are a nice historical anecdote. In his original 1948 paper Jeffress definitely considered the superior olive as a candidate locus because of its anatomical connections. He rejected this possibility based on evidence for phase-locking to the two ears and their "equal representation" at the level of the lateral lemniscus, which is above the superior olive. The finding in 1957/1958 of binaural interaction at the level of the lateral lemniscus and superior olive showed that Jeffress' original hunch regarding the superior olive was correct.

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