Distinct Corticostriatal and Intracortical Pathways Mediate Bilateral Sensory Responses in the Striatum

Cereb Cortex. 2016 Dec;26(12):4405-4415. doi: 10.1093/cercor/bhw268. Epub 2016 Sep 24.

Abstract

Individual striatal neurons integrate somatosensory information from both sides of the body, however, the afferent pathways mediating these bilateral responses are unclear. Whereas ipsilateral corticostriatal projections are prevalent throughout the neocortex, contralateral projections provide sparse input from primary sensory cortices, in contrast to the dense innervation from motor and frontal regions. There is, therefore, an apparent discrepancy between the observed anatomical pathways and the recorded striatal responses. We used simultaneous in vivo whole-cell and extracellular recordings combined with focal cortical silencing, to dissect the afferent pathways underlying bilateral sensory integration in the mouse striatum. We show that unlike direct corticostriatal projections mediating responses to contralateral whisker deflection, responses to ipsilateral stimuli are mediated mainly by intracortical projections from the contralateral somatosensory cortex (S1). The dominant pathway is the callosal projection from contralateral to ipsilateral S1. Our results suggest a functional difference between the cortico-basal ganglia pathways underlying bilateral sensory and motor processes.

Keywords: barrel cortex; corticostriatal pathways; in vivo whole-cell recordings; sensory integration; sensory striatum.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Afferent Pathways / cytology
  • Afferent Pathways / physiology
  • Animals
  • Corpus Callosum / cytology
  • Corpus Callosum / physiology
  • Corpus Striatum / cytology
  • Corpus Striatum / physiology*
  • Female
  • Functional Laterality / physiology*
  • Male
  • Mice, Inbred C57BL
  • Microelectrodes
  • Motor Cortex / cytology
  • Motor Cortex / physiology*
  • Neuroanatomical Tract-Tracing Techniques
  • Neurons / cytology
  • Neurons / physiology*
  • Patch-Clamp Techniques
  • Somatosensory Cortex / cytology
  • Somatosensory Cortex / physiology*
  • Touch Perception / physiology*
  • Vibrissae / physiology