The thalamus is more than just a relay

SM Sherman - Current opinion in neurobiology, 2007 - Elsevier
Current opinion in neurobiology, 2007Elsevier
The lateral geniculate nucleus and pulvinar are examples of two different types of relay: the
former is a first order relay, transmitting information from a subcortical source (retina), while
the latter is mostly a higher order relay, transmitting information from layer 5 of one cortical
area to another cortical area. First and higher order thalamic relays can also be recognized
for much of the rest of thalamus, and most of thalamus seems to be comprised of higher
order relays. Higher order relays seem especially important to general corticocortical …
The lateral geniculate nucleus and pulvinar are examples of two different types of relay: the former is a first order relay, transmitting information from a subcortical source (retina), while the latter is mostly a higher order relay, transmitting information from layer 5 of one cortical area to another cortical area. First and higher order thalamic relays can also be recognized for much of the rest of thalamus, and most of thalamus seems to be comprised of higher order relays. Higher order relays seem especially important to general corticocortical communication, and this challenges and extends the conventional view that such communication is based on direct corticocortical connections.
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