Memory is, in many ways, what makes us human. Each of us has the genetic makeup that endows us with the uniquely human capacity for complex learning and memory, abstractions, symbols, language and conscious thought. Our individual differences as human beings emerge from an interaction of genetics, environment, and experience from which we store countless memories that provides us with the ability to explore, interpret, and analyze what we know as “life”.
Memory occurs in stages. First, we focus our attention on what is interesting, what is most relevant to our motivations and goals. Then we start to store information that will help us achieve our goals in the future. During this process of learning, the storage of information becomes more and more permanent, until ultimately we form memories that can last throughout our entire lifetimes, allowing us to recall events that occurred many decades earlier in our experience.
Human memory is associative. Associations are the links or relationships that are formed between the pieces of information occurring repeatedly in our experience. These may be faces connected with names, names connected with places or numbers connected with times of our lives. Information that becomes associated in memory can also provide details within an image, such as the features of eyes, mouth, nose and hair that together construct a familiar face, a place or a name.
More than 100 years of neuroscience research has revealed the brain to be a miraculous assembly of millions of nerve cells or neurons that are connected together at billions of junctions called synapses. We also now know that memories are stored by changing the strengths of these synaptic connections. Memory storage also involves changes in the actual structure of the synapses, sometimes forming more of special types of synapses that are made on small, mushroom-shaped protrusions, or spines that proliferate throughout the numerous branches of each neuron. Researchers at Blanchette Rockefeller Neurosciences Institute (BRNI) and scientists around the world are still deciphering the fine details of the chemical and molecular processes by which memories are formed and stored.
At BRNI, our primary basic research focuses on the molecular pathways of memory- - identification and understanding of those molecular events responsible for the changes of synaptic connections that store the associations learned from experience. BRNI observations have demonstrated that synaptic changes during memory involve not only changes of molecular signaling and structure but also the sequence of functions responsible for the transfer of information across the synapse. These include chemical receptors, ionic channels within synaptic membranes, and regulatory proteins.
In recent years, these same molecular signaling pathways that change synapses to store memories have been found to change during diseases of memory such as Alzheimer’s disease. In fact, the loss of synapses that can be measured in the brains of Alzheimer’s patients has been shown by a number of laboratories to be the only brain change to be closely correlated with the loss of memory and cognitive functions in a patient’s life experience. It is not surprising, therefore, that drugs developed at BRNI to enhance synaptic formation, i.e. synaptogenesis, show a remarkable capacity in animal models, to prevent and reverse the loss of synapses as well as the other changes of proteins that are toxic to the brain in Alzheimer’s disease.
Thus, a comprehensive and deep understanding of molecular events that regulate synapses during memory formation have provided new insights into diseases of synapses, not only in Alzheimer’s disease, but stroke, traumatic brain injury (TBI) and aging itself. This understanding has also guided the development of highly potent and specific drugs, our primary applied research, with the promise of creating a new era of therapeutics to rescue the dying neurons and synapses in our aging years.