The LGN and pulvinar (a massive but generally mysterious and ignored thalamic relay) are examples of two different types of relay: the LGN is a first order relay, transmitting information from a subcortical source (retina), while the pulvinar is mostly a higher order relay, transmitting information from layer 5 of one cortical area to another area. First and higher order thalamic relays can also be recognized for the somatosensory and auditory thalamic systems, and this division of thalamic relays can also be extended beyond sensory systems. Most of thalamus is comprised of higher order relays. Higher order relays seem especially important to general corticocortical communication, and this view challenges and extends the conventional view that such communication is based mainly on direct corticocortical connections. In this sense, any new information reaching a cortical area, whether from a subcortical source or another cortical area, benefits from a thalamic relay. Thus the thalamus is not just a simple relay responsible for getting peripheral information to cortex. Instead it both provides a behaviorally relevant, dynamic control over the nature of information relayed, and it also plays a key role in basic corticocortical communication.