The discovery of stem cells in the adult brain has generated a great deal of excitement in the neurosciences. Thousands of new cells are produced each day in a healthy hippocampus, a key brain area for learning and memory. However, soon after the cells are born, many of them die unless they are exposed to a learning experience. Thus, new neurons in the adult are rescued from death by learning. With this award, a number of important questions about the relationship between learning and neurogenesis will be answered: What do new neurons do once they are rescued from death? Are they used for memory or for acquiring new information? Are new cells retained with each new learning experience and if so, do they then contribute to learning in the future? Also, do the absolute numbers that are born relate to the numbers kept alive by learning? And finally, what physiological mechanisms and brain rhythms keep them alive? To answer these questions, behavioral, electrophysiological, molecular and biochemical techniques will be used. These studies are important because they will identify the critical features of learning that keep new neurons alive and in turn how those new neurons then contribute to optimal learning in the future. The discovery of neurogenesis has transformed the way we think about the adult brain and generated much interest in the public, especially educators of children and young adults. These findings will be disseminated to the public with writings in lay magazines (i.e. Shors, Scientific American, 2009) and public presentations (i.e. Quark Park, a public art installation about science). The project will train postdoctoral, graduate and undergraduate students in this new field of research which intersects biology, psychology, physiology, as well as biomedical and stem cell engineering.
" INTELLECTUAL MERIT ACCOMPLISHMENTS: The brain continues to produce new neurons throughout life. For instance, the hippocampus (a brain region necessary for select learning processes) produces thousands of new neurons each day. However, a significant number of them die and do so within just a few weeks of their birth. With this award, it was determined that the types of skills that keep new cells alive are not limited to those that depend on the hippocampus but rather include those that are difficult to learn, as demonstrated by the number of trials of training or time spent training. For example, animals that require more trials of training to learn, provided that they do learn, retain more new neurons than animals that learn very quickly. Therefore, some degree of effort is necessary to engage the neurons to survive and more effort is necessary to learn a more difficult task. It was also determined that learning itself must occur. Animals that are trained and don't learn do not retain more cells than animals that are not trained. Finally, the task itself must be new; training on a task that is already learned does not keep the new neurons alive. These studies indicate that learning increases the survival of newly-generated cells in the hippocampus as long as the learning experience is new, effortful and successful (Shors, 2014). Once rescued, the vast majority of these cells differentiate into neurons, thereby forming synapses and generating action potentials as they become incorporated into the existing architecture and functional circuitry in the adult brain. BROADER IMPACT ACTIVITIES AND ACCOMPLISHMENTS: A goal of the NSF is to develop new approaches to engage underserved individuals, groups, and communities in science and technology and to involve the public, wherever possible, in research and educational activities. To this end, Dr. Shors and a team of scientists at Rutgers University developed a training program for humans, which evolved from laboratory studies addressing neurogenesis and learning in the adult brain. The program is referred to as MAP Training because it combines "mental and physical" training activities (Curlik and Shors, 2013; Shors et al., 2014). MAP Training was provided to more than 100 students on campus as well as previously homeless young mothers within the local community, producing positive outcomes in their lives. Throughout the award, the Shors laboratory hosted undergraduate students from universities and colleges around the country (including Puerto Rico) as part of the Research in Science and Education (RISE) Program. The program provides 8-10 weeks of laboratory experience to students from underrepresented groups with exceptional academic and societal accomplishments. Most of these students continued with graduate studies in neuroscience and/or psychology. The laboratory trained Rutgers university from 5-10 undergraduates each year as well as 3-4 doctoral students. Graduate students went on to complete post-doctoral training in neuroscience and several secured tenure-track positions at major research institutions. One of the post-doctoral fellows received an INSPIRE award, which supports training in neuroscientific research and teaching at minority-serving institutions, while another former post-doctoral fellow is conducting funded research at the University of Jyväskylä (JyU) in Finland.
