Evidence suggests rhythmic whisker movements in rats are driven by a subcortical central pattern generator(CPG) under control of the whisker motor cortex (wMCx). Additionally, it has been demonstrated thatserotonin (5HT) is necessary for whisking. My goal is to investigate a subset of 5HT neurons in thebrainstem of adult rats that are likely to comprise an integral part of the whisking CPG. I will investigate thecontrol exerted by the wMCx over this putative CPG component and the impact that the resulting CPGmodulation has on whisking frequencies. I propose that the 5HT CPG determines firing frequency of whiskermotor units by regulating the delivery of 5HT to motoneurons in the lateral facial nucleus. I further proposethat 5HT regulates motor unit firing rates by facilitating a persistent inward current in whisker motoneurons(wMNs) in a dose dependent manner. I will investigate the ability of 5HT to facilitate a dose dependent PIC inwhisker motoneurons and its relation to whisker motoneuron firing frequency.
Cramer, Nathan P; Li, Ying; Keller, Asaf (2007) The whisking rhythm generator: a novel mammalian network for the generation of movement. J Neurophysiol 97:2148-58 |
Cramer, Nathan P; Keller, Asaf (2006) Cortical control of a whisking central pattern generator. J Neurophysiol 96:209-17 |
Friedman, Wendy A; Jones, Lauren M; Cramer, Nathan P et al. (2006) Anticipatory activity of motor cortex in relation to rhythmic whisking. J Neurophysiol 95:1274-7 |