Dissociation of Morphological and Physiological Changes Associated With Long-Term Memory in Aplysia

• Published in: Journal of neurophysiology 2004-10, Vol.92 (4), p.2628-2632
• Main Authors: Wainwright, Marcy L, Byrne, John H, Cleary, Leonard J
• Format: Article
• Language: English
• Subjects: Animals; Aplysia; Aplysia - anatomy & histology; Aplysia - physiology; Conditioning, Classical - physiology; Ganglia, Invertebrate - cytology; Ganglia, Invertebrate - physiology; Marine; Memory - physiology; Microscopy, Confocal; Nervous System - cytology; Nervous System - growth & development; Nervous System Physiological Phenomena; Neurites - physiology; Neuronal Plasticity; Neurons - physiology; Neurons - ultrastructure; Synapses - physiology
• ISSN: 0022-3077; 1522-1598
• DOI: 10.1152/jn.00335.2004

W. M. Keck Center for the Neurobiology of Learning and Memory, Department of Neurobiology and Anatomy, The University of Texas Medical School at Houston, Houston, Texas 77030 Submitted 2 April 2004; accepted in final form 2 June 2004 Neurite outgrowth is a process commonly thought to contribute to long-term learning by formation of new synaptic contacts. The behavioral effects of long-term sensitization training in Aplysia were restricted to the trained side of the animal as were changes in strength of the sensorimotor synapse. In contrast, training produced varicosity formation on both sides of the animal. Appositions with follower neurons, however, were enhanced only on the trained side. The dissociation of structural and functional correlates suggests that key regulatory steps are downstream from outgrowth, possibly in the targeting of new processes and activation of new synapses. Address for reprint requests and other correspondence: L. J. Cleary, Dept. of Neurobiology and Anatomy, The University of Texas Medical School at Houston, 6431 Fannin St., Houston, TX 77030 (E-mail: len.cleary{at}uth.tmc.edu ).