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4 Headlines Questions on memory with Dr Owen Jones Dr Owen Jones is a Research Fellow in the Department of Psychology at the University of Otago. He was recently awarded a Neurological Foundation project grant in the 2022A grant round for a study into frontotemporal dementia. What part of our brain is used for memory? Memories are formed and stored in circuits that span multiple brain regions. A study in 2019 looked at brain lesions that cause retrograde amnesia (inability to form new memories). Over 95% of the lesions that caused amnesia involved damage to the hippocampus, so it's reasonable to assume this area is heavily involved in memory. The type of memory will influence where it is formed and stored. For example, your short-term working memory is thought to rely heavily on the prefrontal cortex, and your memory of how to perform certain movements or procedures will rely heavily on your midbrain. How are memories formed? A great question! It's believed memories are formed and stored by changing the connections (synapses) between nerve cells. If cells are highly active during learning, their connections will strengthen, and this allows information to be stored and recalled. There are other things too, but changes in synapse strength are the best understood memory mechanism. Why can we not remember when we are born? There are different theories on this. First, ‘infantile amnesia’ might reflect the fact that we don't develop language in our first year of life, so we don't have the appropriate tools to describe our experiences (and therefore store them away as memories). A newer theory is that we produce new brain cells at a prolific rate during the first couple of years of life, and the new brain cells keep ‘overwriting’ the information stored in the old ones. How and why did memory evolve? Memory is ancient. Even single cell organisms like bacteria have some forms of simple memory that help them adapt to changes in their environment. All early animals developed circuits for simple ‘reinforcement’ memory based on reward or punishment. Then we see memory based on map-like representations in the brain in early vertebrates, which would be beneficial for navigation as well as other things. By the time we get to primates we see brain regions capable of advanced feature memory (item, location, colour, shape, size, etc) that allow for more complex memories of events. Human memory reflects hundreds of millions of years of adaptations, each conferring its own advantages. What exciting new research is happening in understanding memory? Several lines of inquiry have gathered steam recently. One interesting question is whether memory deficits in conditions such as Alzheimer's disease are due to the loss of memories, or whether they are still there but cannot be accessed or recalled. Another issue that's attracting more and more interest is the role of ‘glial’ cells in forming, maintaining, and retrieving memories. These cells used to just be considered support cells, with neurons (nerve cells) doing all the important information storage. Nowadays we're not so sure. Are memories reliable? Not always, no. We like to think of our memories as perfect video clips, but in reality, our memories are constructed rather than recorded. There are plenty of experiments that A closer look at: MEMORY In each Headlines this year we take a closer look at a particular feature of neurology impacting Kiwis. In this edition we look at memory. M emory is one of the most important fields of study in neuroscience. Many brain disorders, from dementias such as Alzheimer's to stroke and traumatic brain injury, result in memory loss. Problems with memory are extremely distressing for people experiencing them and for their families. Understanding how our brain forms and stores memories is a key goal for neurological research as it is essential in designing effective treatments to stave off, or even restore memory decline. In this edition we talk to Dr Owen Jones a Research Fellow in the Department of Psychology, University of Otago, about memory and how it works. We also visit two groundbreaking Neurological Foundation- funded research projects that are investigating memory to better understand how to treat memory-related brain diseases and injuries. Enjoy!