Publication Date:
2013-07-03
Description:
The thalamocortical (TC) projection to layer 4 (L4) is thought to be the main route by which sensory organs communicate with cortex. Sensory information is believed to then propagate through the cortical column along the L4--〉L2/3--〉L5/6 pathway. Here, we show that sensory-evoked responses of L5/6 neurons in rats derive instead from direct TC synapses. Many L5/6 neurons exhibited sensory-evoked postsynaptic potentials with the same latencies as L4. Paired in vivo recordings from L5/6 neurons and thalamic neurons revealed substantial convergence of direct TC synapses onto diverse types of infragranular neurons, particularly in L5B. Pharmacological inactivation of L4 had no effect on sensory-evoked synaptic input to L5/6 neurons. L4 is thus not an obligatory distribution hub for cortical activity, and thalamus activates two separate, independent "strata" of cortex in parallel.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4203320/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4203320/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Constantinople, Christine M -- Bruno, Randy M -- NS069679/NS/NINDS NIH HHS/ -- R01 NS069679/NS/NINDS NIH HHS/ -- T32 HD007430/HD/NICHD NIH HHS/ -- New York, N.Y. -- Science. 2013 Jun 28;340(6140):1591-4. doi: 10.1126/science.1236425.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Neuroscience and Kavli Institute for Brain Science, Columbia University, New York, NY 10032, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23812718" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
*Evoked Potentials, Somatosensory
;
Neocortex/cytology/drug effects/*physiology
;
Neurons/drug effects/physiology
;
Rats
;
Rats, Wistar
;
Synapses/drug effects/physiology
;
Thalamus/cytology/drug effects/*physiology
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
