Close your eyes and think about the last time you were at the beach. You hear the waves, take in the salty air and feel the sun on your face. Maybe you were happy, perhaps not. We do this without thinking, but how the brain forms, stores and retrieves these kinds of memories on multiple dimensions is a mystery. Neurophysiologist Francesco Battaglia received a scholarship to look for the answers. ‘All things that together compose our memories, from smells, sounds, tastes and images to emotions, are stored in different locations of your brain. And they can be mere centimeters apart’, Battaglia explains. Scientists think that the brain contains a kind of network that connects these locations. Because only in this way can all facets of memories be saved as a single memory. But as of yet, researchers only have a suspicion about how the details of how this works. Francesco Battaglia goes in search of the answers. His study is the first research that examines the entire cortex, the place in our brain where information is received, analysed and interpreted. Previous studies have only looked at portions of the cortex. For the research study, which will last five years, Battaglia received an EU grant of 2.5 million euros. Conscious brain The impetus for the study was a neuroscientific insight from 2001. ‘Neuroscientists discovered that there is a network in the brain that is more active when you sleep than when you are doing nothing. This is called the ‘default mode network’. I think this network is crucial for storing information in the brain’, explains Battaglia. The reason for this is that this network is closely linked to the hippocampus. The hippocampus is located in the core of the brain. This is where the anchor of a memory is tethered. But the hippocampus is no more than an inch across, and its capacity is limited. The information is therefore transported to the much larger cortex on the outer layer of the brain. The information is stored there long term. In his research, Battaglia examines how the hippocampus and the cortex communicate with each other via the default mode network. He expects the network plays a crucial role in synchronising the information in the hippocampus with the cortex. He also suspects that this network plays a significant role in bridging the distances between the different places in the cortex where information is stored. Battaglia hopes to succeed in reconstructing these information networks in our brain with highly accurate data. ‘The individual neurons, that's where the information I need is stored.’ To map this out, Battaglia will use an electron microscope. This allows him to view the brains of living animals in a virtual reality environment. The microscope is an asset to the lab, which can also be used by other researchers. From Alzheimer to identity Battaglia expects the study to provide them with greater insight into memory disorders, such as Alzheimer's and post-traumatic stress disorder. Was he surprised to find that so much happens in our brains when we sleep? ‘No, not at all. Our brain is not a machine that only responds to input. The brain is a creative entity that also functions autonomously. That may explain why we are creative beings.’ With his research, Battaglia hopes to get closer to the answer of who we are. ‘Because our memories make us who we are. After all,’ Battaglia asks, ‘if I take away your memory, what’s left?’