title: Characteristics of synaptic connections between rodent primary somatosensory and motor cortices.
abstract: The reciprocal connections between primary motor (M1) and primary somatosensory cortices (S1) are hypothesized to play a crucial role in the ability to update motor plans in response to changes in the sensory periphery. These interactions provide M1 with information about the sensory environment that in turn signals S1 with anticipatory knowledge of ongoing motor plans. In order to examine the synaptic basis of sensorimotor feedforward (S1-M1) and feedback (M1-S1) connections directly, we utilized whole-cell recordings in slices that preserve these reciprocal sensorimotor connections. Our findings indicate that these regions are connected via direct monosynaptic connections in both directions. Larger magnitude responses were observed in the feedforward direction (S1-M1), while the feedback (M1-S1) responses occurred at shorter latencies. The morphology as well as the intrinsic firing properties of the neurons in these pathways indicates that both excitatory and inhibitory neurons are targeted. Differences in synaptic physiology suggest that there exist specializations within the sensorimotor pathway that may allow for the rapid updating of sensory-motor processing within the cortex in response to changes in the sensory periphery.
authors: Neuropsychology PhD Subprogram (Psychology), The Graduate Center, CUNY, New York, USA.
authors: Mary
authors: M
authors: Rocco-Donovan
authors: Raddy L
authors: RL
authors: Ramos
authors: Sandra
authors: S
authors: Giraldo
authors: Joshua C
authors: JC
authors: Brumberg
mesh_terms: D000818:Animals; D001931:Brain Mapping; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology*; D025461:Feedback, Physiological; D066298:In Vitro Techniques; D051379:Mice; D009044:Motor Cortex / Q000166:cytology / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D018408:Patch-Clamp Techniques; D013003:Somatosensory Cortex / Q000166:cytology / Q000502:physiology*; D013569:Synapses / Q000502:physiology*; D014738:Vibrissae / Q000502:physiology