Higher-order thalamic relays burst more than first-order relays.

نویسندگان

  • E J Ramcharan
  • J W Gnadt
  • S M Sherman
چکیده

There is a strong correlation between the behavior of an animal and the firing mode (burst or tonic) of thalamic relay neurons. Certain differences between first- and higher-order thalamic relays (which relay peripheral information to the cortex versus information from one cortical area to another, respectively) suggest that more bursting might occur in the higher-order relays. Accordingly, we recorded bursting behavior in single cells from awake, behaving rhesus monkeys in first-order (the lateral geniculate nucleus, the ventral posterior nucleus, and the ventral portion of the medial geniculate nucleus) and higher-order (pulvinar and the medial dorsal nucleus) thalamic relays. We found that the extent of bursting was dramatically greater in the higher-order than in the first-order relays, and this increased bursting correlated with lower spontaneous activity in the higher-order relays. If bursting effectively signals the introduction of new information to a cortical area, as suggested, this increased bursting may be more important in corticocortical transmission than in transmission of primary information to cortex.

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عنوان ژورنال:
  • Proceedings of the National Academy of Sciences of the United States of America

دوره 102 34  شماره 

صفحات  -

تاریخ انتشار 2005