TitleLearning increases the survival of newborn neurons provided that learning is difficult to achieve and successful
NameCurlik, II, Daniel (author), Shors, Tracey J (chair), Otto, Timothy (internal member), Matzel, Louis (internal member), Rutgers University, Graduate School - New Brunswick,
DescriptionProcesses of learning can increase the survival of new neurons generated in the adult hippocampal formation (Gould et al., 1999; Shors, 2009). However, only some types of learning are effective. Recent studies demonstrate that animals that learn the conditioned response (CR), but require more trials to do so, rescue more new neurons than animals that quickly acquire the CR, or those that fail to acquire the CR. These studies altered task parameters to modify the number of trials required to learn a conditioned response. Here we asked whether pharmacological manipulations that decrease or increase learning would decrease and increase, respectively, the number of cells that remain in the hippocampus after training. To answer this question, we first prevented learning with the competitive NMDA receptor antagonist (±)-3-(2-Carboxypiperazin-4-yl)propyl-1-phosphonic acid (CPP). Administration of the NMDA receptor antagonist CPP each day before training prevented acquisition of the trace eyeblink response, and the subsequent increase in neuronal survival. Second, we facilitated learning with the cognitive enhancer d-cycloserine (DCS), a compound that increases NMDA receptor activity via its actions at the glycine binding site. Administration of the NMDA receptor partial agonist DCS each day before training increased the number of learned responses and the number of cells that survived. Animals that successfully acquired the CR early in training possessed more cells than those exposed to unpaired stimuli but those that learned later in training retained even more newborn neurons. DCS & CPP did not alter performance or cell number when administered after training. These results demonstrate that NMDA receptor activation modifies learning and as a consequence, alters the number of surviving neurons in the hippocampus. Moreover, they demonstrate that associative learning increases neuronal survival provided that the learning is both difficult to achieve and successful .
NoteIncludes bibliographical references
Noteby Daniel M. Curlik II
CollectionGraduate School - New Brunswick Electronic Theses and Dissertations
Organization NameRutgers, The State University of New Jersey
RightsThe author owns the copyright to this work.