The mammalian striatum receives its main excitatory input from the two types of cortical pyramidal neurons of layer 5 of the cerebral cortex – those with only intratelencephalic connections (IT-type) and those sending their main axon to the brainstem via the pyramidal tract (PT-type). These two neurons types are present in layer 5 of all cortical regions, and thus they appear to project together to all parts of striatum. These two neuron types, however, differ genetically, morphologically, and functionally, with IT-type neurons conveying sensory and motor planning information to striatum and PT-type neurons conveying an efference copy of motor commands (for motor cortex at least). Anatomical and physiological data for rats, and more recent data for primates, indicate that these two cortical neuron types also differ in their targeting of the two main types of striatal projection neurons, with the IT-type input preferentially innervating direct pathway neurons and the PT-type input preferentially innervating indirect pathway striatal neurons. These findings have implications for understanding how the direct and indirect pathways carry out their respective roles in movement facilitation and movement suppression, and they have implications for understanding the role of corticostriatal synaptic plasticity in adaptive motor control by the basal ganglia.
Keywords: striatum, cortex, spines, synapses, projection neurons
Citation: Reiner A, Hart NM, Lei W and Deng Y (2010) Corticostriatal projection neurons – dichotomous types and dichotomous functions. Front. Neuroanat. 4:142. doi: 10.3389/fnana.2010.00142
Received: 23 June 2010;
Accepted: 29 September 2010;
Published online: 25 October 2010.
Edited by:Jose L. Lanciego, University of Navarra, Spain
Reviewed by:Ann M. Graybiel, Massachusetts Institute of Technology, USA;
Copyright: © 2010 Reiner, Hart, Lei and Deng. This is an open-access article subject to an exclusive license agreement between the authors and the Frontiers Research Foundation, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are credited.
*Correspondence: Anton Reiner, Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, 855 Monroe Ave., Memphis, TN 38163, USA. e-mail: email@example.com; Wanlong Lei, Department of Anatomy, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd 2, Guangzhou 510080, China. e-mail: firstname.lastname@example.org