ASET Colloquium
Using the restricted neuronal networks of an invertebrate to understand how coordinated rhythmic activity in produced by the nervous system
by Prof. Ronald L. Calabrese (Department of Biology, Emory University, USA)
Friday, December 19, 2014
from
to
(Asia/Kolkata)
at AG-66
at AG-66
Description |
Understanding how rhythmic motor patterns are generated and coordinated by central pattern generating neuronal networks (CPGs) has been one of the major advances of the past 20 years in neuroscience. Owing to the relative simplicity of the nervous systems of invertebrates, their analysis, both physiological and computational, has contributed significantly to this understanding. In my lab we have used the leech heartbeat CPG to participate in this analysis. The two longitudinal heart tubes of medicinal leeches are innervated in each midbody segment (3–18) by the ipsilateral member of a single bilateral pair of heart motor. The heart motor neurons fire rhythmically in a coordinated pattern because they are inhibited ipsilaterally by a set of four bilateral pairs of identified of premotor heart interneurons that are members of the rhythmically active heartbeat CPG. The fictive motor pattern for heartbeat is bilaterally asymmetric: motor neurons on one side fire in a rear-to-front progression (peristaltic), whereas those on the other fire in near synchrony (synchronous) and there is side-to-side coordination of the two patterns. The asymmetry is not permanent, but rather the motor neurons of the two sides change roles (patterns) every 20–40 heartbeat cycles. The temporal pattern of the activity of the premotor interneurons has been described quantitatively and, like that of the motor neurons, is bilaterally asymmetric with strict side-to-side coordination and regular side-to-side switches of peristaltic and synchronous patterns. In this talk, we will explore how the basic rhythm is generated by network motifs of mutually inhibitory interneurons (so- called half-center oscillators) in the CPG and how the two alternating coordination modes are generated and switched. 1: Lamb DG, Calabrese RL. Neural circuits controlling behavior and autonomic functions in medicinal leeches. Neural Syst Circuits. 2011 Sep 28;1(1):13. doi: 10.1186/2042-1001-1-13. PubMed PMID: 22329853; PubMed Central PMCID: PMC3278399. REVIEW 2: Kristan WB Jr, Calabrese RL, Friesen WO. Neuronal control of leech behavior. Prog Neurobiol. 2005 Aug;76(5):279-327. Epub 2005 Nov 2. Review. PubMed PMID: 16260077. REVIEW |
Material: | |
Organised by | Dr. Satyanarayana Bheesette |
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