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How are memories created in the brain? I’ve been working on this for 45 years, so I’ll give you the short version. At the most basic level, memories are formed through changes in the connections between nerve cells, which are called synapses. These connections are modifiable, or “plastic” – they can strengthen or weaken over time. When we experience something, relevant networks of neurons become active. The synapses between them can grow stronger, making it easier to reactivate that same network later when we want to recall that information. Some connections strengthen, others weaken, and that reshapes how information flows through the brain. Why do some memories stick while others disappear? There are a few key factors. First, attention. If you’re not paying attention, you’re unlikely to remember it. Second, repetition. I tell my students that repetition is the mother of memory. Third, emotional significance. Events that are emotionally engaging tend to stick, possibly because they are also frequently rehearsed. And fourth, how deeply you process the information. If you connect it to things you already know, you’re much more likely to retain it. What was your earliest memory? Old memories don’t come with timestamps, so it’s almost impossible to knowwhich one came first. But one early memory has always stayed with me. My family was visiting friends who had a speedboat, and we were sitting on a steep bank above a river while my sister was water skiing. Somehow, I started sliding down the bank, closer and closer to the water. It was quite frightening. I was scrambling to stop myself but couldn’t, and eventually I ended up stuck, heart racing, unable to climb back up. In the end, my father came sliding down and rescued me. It was quite an emotional experience, and it’s stayed with me ever since. Why does Alzheimer’s seem to affect short-term memory first? It’s often described as a short-termmemory problem, but that’s not quite accurate. Short-termmemory itself is usually still functioning. The real issue is with consolidation – the process of transferring information from short-term into long-term storage. In conditions like Alzheimer’s, that process is impaired, so newmemories aren’t effectively stored. Should we worry about everyday forgetfulness as we age? Not necessarily. Things like forgetting why you walked into a room or struggling to recall names are very common. And many factors not related to neurological disease can cause memory problems, such as some medications, depression, and sleep loss. There’s no need to worry if you forget where you parked your car, but if you forget you had a car in the first place, that’s a different matter. The key question is whether it’s getting progressively worse. Normal ageing might involve a gradual decline, but disease-related changes tend to show a much steeper trajectory and become noticeable to others as well. Are younger people experiencing more memory problems today? There is some evidence that younger people are reporting more memory issues, particularly since the pandemic. But it’s probably not because the brain’s memory mechanisms have changed. Another defining moment of Cliff’s career was receiving the RutherfordMedal, New Zealand’s highest scientific honour. “I was surprised, but incredibly honoured. To be recognised among that group of previous winners was very humbling.” The award reflects a philosophy he has carried throughout his career, drawn fromNew Zealand scientist Lord Ernest Rutherford: “We don’t have a lot of money, so we’ll have to think.” The lack of money to sustain high- quality neuroscience in New Zealand remains top-of- mind for Cliff as he enters retirement. When the Government did not renew the funding for brain research under its Centre of Research Excellence initiative, it signalled a shift in research funding priorities for years to come. “Neurological diseases have a very high cost to society, but the investment in research doesn’t match that,” says Cliff. “Of course you don’t get every grant you apply for. But the success rate has gone down quite substantially. “Saying that, when I arrived in New Zealand, there were only a small number of researchers working in neuroscience. Now there are many big teams, adding to the competition,” he says. “Still, neuroscience in New Zealand is very strong and will carry on.” While time with family will take priority, he expects to remain connected to our neuroscience community, supporting ongoing research, advising where he can – and perhaps adding a final piece or two to the jigsaw. Cliff with two longstanding colleagues, Dr Owen Jones (left) and Dr Bruce Mockett. The story of memory: Q+A with Cliff Piecing it together: Cliff has always enjoyed puzzles, leading to his fascination for howwe formmemories. Cliff shares some parting thoughts on page 9  “There’s no need to worry if you forget where you parked your car, but if you forget you had a car in the first place, that’s a different matter.” 6 Headlines 7 Headlines