In neuroscience, synaptic plasticity is the ability of synapses to strengthen or weaken over time, in response to increases or decreases in their activity. Since memories are postulated to be represented by vastly interconnected neural circuits in the brain, synaptic plasticity is one of the important neurochemical foundations of learning and memory.
A neurochemical is a small organic molecule or peptide that participates in neural activity. The science of neurochemistry studies the functions of neurochemicals.
A neural circuit is a population of neurons interconnected by synapses to carry out a specific function when activated. Multiple neural circuits interconnect with one another to form large scale brain networks.
Activity-dependent plasticity is a form of functional and structural neuroplasticity that arises from the use of cognitive functions and personal experience; hence, it is the biological basis for learning and the formation of new memories. Activity-dependent plasticity is a form of neuroplasticity that arises from intrinsic or endogenous activity, as opposed to forms of neuroplasticity that arise from extrinsic or exogenous factors, such as electrical brain stimulation- or drug-induced neuroplasticity. The brain's ability to remodel itself forms the basis of the brain's capacity to retain memories, improve motor function, and enhance comprehension and speech amongst other things. It is this trait to retain and form memories that is associated with neural plasticity and therefore many of the functions individuals perform on a daily basis. This plasticity occurs as a result of changes in gene expression which are triggered by signaling cascades that are activated by various signaling molecules during increased neuronal activity.
Nonsynaptic plasticity is a form of neuroplasticity that involves modification of ion channel function in the axon, dendrites, and cell body that results in specific changes in the integration of excitatory postsynaptic potentials and inhibitory postsynaptic potentials. Nonsynaptic plasticity is a modification of the intrinsic excitability of the neuron. It interacts with synaptic plasticity, but it is considered a separate entity from synaptic plasticity. Intrinsic modification of the electrical properties of neurons plays a role in many aspects of plasticity from homeostatic plasticity to learning and memory itself. Nonsynaptic plasticity affects synaptic integration, subthreshold propagation, spike generation, and other fundamental mechanisms of neurons at the cellular level. These individual neuronal alterations can result in changes in higher brain function, especially learning and memory. However, as an emerging field in neuroscience, much of the knowledge about nonsynaptic plasticity is uncertain and still requires further investigation to better define its role in brain function and behavior.
Developmental plasticity is a general term referring to changes in neural connections during development as a result of environmental interactions as well as neural changes induced by learning. Much like neuroplasticity, or brain plasticity, developmental plasticity is specific to the change in neurons and synaptic connections as a consequence of developmental processes. A child creates most of these connections from birth to early childhood. There are three primary methods by which this may occur as the brain develops, but critical periods determine when lasting changes may form. Developmental plasticity may also be used in place of the term phenotypic plasticity when an organism in an embryonic or larval stage can alter its phenotype based on environmental factors. However, a main difference between the two is that phenotypic plasticity experienced during adulthood can be reversible, whereas traits that are considered developmentally plastic set foundations during early development that remain throughout the life of the organism.
Thomas Christian Südhof, ForMemRS, is a German-American biochemist known for his study of synaptic transmission. Currently, he is a professor in the School of Medicine in the Department of Molecular and Cellular Physiology, and by courtesy in Neurology, and in Psychiatry and Behavioral Sciences at Stanford University.
The NAS Award in the Neurosciences is awarded by the U.S. National Academy of Sciences "in recognition of extraordinary contributions to progress in the fields of neuroscience, including neurochemistry, neurophysiology, neuropharmacology, developmental neuroscience, neuroanatomy, and behavioral and clinical neuroscience." It was first awarded in 1988.
Malleability of intelligence describes the processes by which intelligence can increase or decrease over time and is not static. These changes may come as a result of genetics, pharmacological factors, psychological factors, behavior, or environmental conditions. Malleable intelligence may refer to changes in cognitive skills, memory, reasoning, or muscle memory related motor skills. In general, the majority of changes in human intelligence occur at either the onset of development, during the critical period, or during old age.
Stephen J Smith is Meritorious Investigator at the Allen Institute for Brain Science [1] and Emeritus Professor of Molecular and Cellular Physiology at Stanford University [2]. He held faculty and Howard Hughes Medical Institute positions at the Yale University School of Medicine 1980-1989. He served 1990-2014 as a Stanford Professor, teaching many courses in synaptic physiology and cellular microscopy while mentoring many students and fellows [3]. He also taught in many expert workshops and summer courses at the Woods Hole Marine Biological Laboratory and the Cold Spring Harbor Laboratory.
Addiction is a state characterized by compulsive engagement in rewarding stimuli, despite adverse consequences. The process of developing an addiction occurs through instrumental learning, which is otherwise known as operant conditioning.
Guoping Feng is a Chinese-American neuroscientist. He is the Poitras Professor of Neuroscience at the McGovern Institute for Brain Research in the Department of Brain and Cognitive Sciences at MIT and member of the Stanley Center for Psychiatric Research at Broad Institute. He is most notable for studying the synaptic mechanisms underlying psychiatric disease. In addition to developing many genetic-based imaging tools for the study of molecular mechanisms in the brain, he has generated and characterized rodent models of obsessive-compulsive disorder, autism spectrum disorders, and schizophrenia. Feng has also shown that some autism-like behaviors can be corrected in adult mice by manipulating the expression of the SHANK3 gene.
Sergiu P. Pașca is a Romanian-American scientist and physician at Stanford University in California. Pașca is a Professor of Psychiatry and Behavioral Sciences at Stanford University and the Bonnie Uytengsu and Family Director of Stanford Brain Organogenesis, a neuroscientist and stem cell biologist and currently a New York Stem Cell Foundation Robertson Investigator. He is part of the Stanford Neurosciences Institute, Stanford Bio-X and a fellow of the ChEM-H Institute at Stanford. Pașca was listed among New York Times Visionaries in Medicine and Sciences, and he is the recipient of the 2018 Vilcek Award for Creative Biomedical Promise from the Vlicek Foundation. In 2022, he gave a TED talk on reverse engineering the human brain in the laboratory
Christian Lüscher is a Swiss neurobiologist and full professor at the Department of Basic Neurosciences of the University of Geneva. He is also an attending in neurology at the Geneva University Hospital. Lüscher is known for his contributions in the field addiction, particularly for establishing links of causality between the drug-evoked synaptic plasticity and adaptive behavior in mice.
Hans Thoenen was a Swiss neurobiologist best known for his work on neurotrophins.
Priya Rajasethupathy is a neuroscientist and assistant professor at the Rockefeller University, leading the Laboratory of Neural Dynamics and Cognition.
HollisT. Cline is an American neuroscientist and the Director of the Dorris Neuroscience Center at the Scripps Research Institute in California. Her research focuses on the impact of sensory experience on brain development and plasticity.
Ilana B. Witten is an American neuroscientist and professor of psychology and neuroscience at Princeton University. Witten studies the mesolimbic pathway, with a focus on the striatal neural circuit mechanisms driving reward learning and decision making.
Kanaka Rajan is a neuroscientist and associate professor in the Department of Neuroscience and Friedman Brain Institute at the Icahn School of Medicine at Mount Sinai in New York City. Rajan trained in engineering, biophysics, and neuroscience, and has pioneered novel methods and models to understand how the brain processes sensory information. Her research seeks to understand how important cognitive functions — such as learning, remembering, and deciding — emerge from the cooperative activity of multi-scale neural processes, and how those processes are affected by various neuropsychiatric disease states. The resulting integrative theories about the brain bridge neurobiology and artificial intelligence.
Marina Elizabeth Wolf is an American neuroscientist and Professor of Behavioral Neuroscience at Oregon Health & Science University. Previously she served as Professor and Chair of the Department of Neuroscience in the Chicago Medical School at Rosalind Franklin University of Medicine and Science. She has been a pioneer in studying the role of neuronal plasticity in drug addiction. Her laboratory is particularly interested in understanding why individuals recovering from substance use disorder remain vulnerable to drug craving and relapse even after long periods of abstinence.
