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My lab team, together with many colleagues at Otago and elsewhere, has been undertaking basic neuroscience research in an attempt to understand the mechanisms of memory storage, with the aim and hope that understanding these normal mechanisms will provide insights into what goes wrong in memory disorders such as Alzheimer’s disease and how to treat them. It is now clear that a fundamental element of memory storage is the experience-dependent changing of the communication between neurons at their synaptic connections. Strengthening some connections while weakening others helps the specific neural circuits activated by experience to become better connected than before and thus more easily reactivated during memory retrieval. Working with ProfessorWarren Tate and Associate Professor JoannaWilliams at Otago, we have been investigating the roles of genes and proteins in memory mechanisms, using animal and cellular models. When changing the structure and function of a nerve cell’s connections, the production of proteins is ramped up by the cell’s molecular machinery, often directed by specific changes in the expression of memory-related genes. Existing and new proteins are modified, shuttled into (or out of) the synaptic contact zones, and the synaptic structures physically change shape as supported and directed by the enzymes manipulating the pool of proteins in the cell. In Alzheimer’s disease, these processes slowly begin to unravel. The processes of synaptic strengthening and enlargement become impaired, while synaptic weakening and shrinking become more prevalent. As these processes begin in some of the key brain regions for storage of personal memories, such as the hippocampus and its connected brain regions, it is no surprise that early signs of Alzheimer’s include impairment of the storage of newmemories. Professor Cliff Abraham, co-director of Brain Research NZ – Ranghau Roro Aotearoa, has research interest in neural mechanisms of memory. He has played a leading role in promoting neuroscience research and teaching at the University of Otago and has promoted neuroscience at a national level by serving as chair of the AustralasianWinter Conference on Brain Research, New Zealand’s annual neuroscience meeting in Queenstown, for 12 years. The brain has evolved to allow animals to move around in their environments and learn from their experiences. Such learning is essential for survival and reproductive success, and so the nervous system has evolved an enormous array of learning mechanisms, termed plasticity mechanisms, to put in its survival toolkit. These plasticity “tools” are not only used for the purposes of learning and memory, but also for the normal development of the nervous system. Is it possible that the same plasticity mechanisms that contribute to normal brain functions, such as learning, and memory, can also be used to recover from brain injury and to fight brain disease? There is now a considerable amount of evidence that this is indeed the case, although the molecular mechanisms of each part of the puzzle are so complicated that it is extremely challenging to put them together for a full understanding. Still, one piece at a time, the international community is making progress. Brain Plasticity: A key to the brain’s resilience against pathology? Professor of Psychology and Co-director of the Brain Research New Zealand - Rangahau Roro Aotearoa. PROFESSOR CLIFF ABRAHAM 4 Headlines