Mechanisms of Locomotory Speed Change: The Pteropod Solution1

• Main Authors: Richard A. Satterlie, Tigran, P. Norekian
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Clione limacina
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.484.6575; http://icb.oxfordjournals.org/content/41/4/1001.full.pdf

SYNOPSIS. Three primary factors contribute to locomotory speed changes in the pteropod mollusk Clione limacina. (1) An increase in cycle frequency of locomotory appendages is associated with a baseline depolarization and enhancement of postin-hibitory rebound in central pattern generator (CPG) interneurons, and a reorga-nization of the CPG through recruitment of additional interneurons. (2) An in-crease in the force of appendage movements is generated through enhancement of activity of active motoneurons, recruitment of additional motoneurons and periph-eral modulation of swim musculature. (3) Changes in biomechanical aspects of appendage movements are presumably achieved, at least in part, through changes in the activity of motoneurons and swim muscle. All changes associated with non-startle swim acceleration are produced by a serotonergic arousal system that acts at all three levels of the swimming system: CPG interneurons, motoneurons and swim musculature.