The BROUGHT TO YOUBRAIN BY UQ'S QUEENSLAND BRAIN INSTITUTE
Issue Five THE NATURE OF DISCOVERY
HOW A JELLYFISH lights up THE BIG the brain QUESTIONS in neuroscience
CONTROLLING THE BRAIN with light What we learn from animal brains SPECIAL REPORT: The BROUGHT TO YOUBRAIN BY UQ'S QUEENSLAND BRAIN INSTITUTE
Issue Five THE NATURE OF DISCOVERY THE NATURE OF DISCOVERY
HOW A JELLYFISH lights up THE BIG the brain QUESTIONS in neuroscience DOWNLOAD, READ AND SHARE qbi.uq.edu.au/nature-discovery CONTROLLING THE BRAIN with light What we learn from animal brains
Publisher Professor Pankaj Sah
Editor Carolyn Barry The BROUGHT TO YOUBRAIN BY UQ'S QUEENSLAND BRAIN INSTITUTE Writers Carolyn Barry Issue Five Dr Fiona McMillan Dr Alan Woodruff THE NATURE OF DISCOVERY
Scientific advisers Associate Professor Tim Bredy HOW A Professor Massimo Hilliard JELLYFISH Dr Dhanisha Jhaveri lights up THE BIG Professor Justin Marshall the brain QUESTIONS Professor Fred Meunier in neuroscience Associate Professor Ethan Scott Emeritus Professor Srini Srinivasan Professor Stephen Williams Dr Steven Zuryn
Designer Katharine McKinnon
The Queensland Brain Institute is located at CONTROLLING The University of Queensland, THE BRAIN St Lucia, QLD, 4072 with light [email protected] What we learn from animal brains The Brain Series: The Nature of Discovery was produced by the Queensland Brain Institute, The University of Queensland, April 2020
FACEBOOK TWITTER INSTAGRAM facebook.com/ twitter.com/ instagram.com/ QldBrainInstitute QldBrainInst QldBrainInstitute CONTENTS A MESSAGE FROM CHAPTER 1 PROFESSOR PANKAJ SAH WHY STUDY THE BRAIN? DIRECTOR, QUEENSLAND BRAIN INSTITUTE 02 Why study the brain? 03 Brain basics ur brains are incredible. 04 Key leaps inspired by nature They allow us to interpret our 06 The state of neuroscience Osensory world, understand and create language, control movements, CHAPTER 2 plan for the future, and so much more. They are complex machines that make ANIMAL INSPIRATION us who we are. 08 Flight: learning from nature Each human brain contains around 100 billion neurons with a Animal sleep 09 trillion possible connections, and 10 Animal vision an even larger number of other support cells. Together, these cells CHAPTER 3 and their connections interpret and move information across the brain LIGHTING UP THE BRAIN according to a logic that, until recently, 12 How the jellyfish was unfathomable. Now, decades revolutionised science of research and some incredible discoveries have given us a deeper 13 Lighting up the tiniest parts understanding of the brain. How did of the brain these discoveries come about, and what lessons do they hold for the
CHAPTER 4 future of brain research? HAMILTON PATRICK One important ingredient has CONTROLLING THE BRAIN been scientists’ desire to understand new therapy—simply wanted to 14 Controlling the brain the basic workings of the many understand ‘how things work’. Later, with light diverse organisms that make up the others used their own creativity to natural world. First, as a product of adapt these discoveries to brain 15 The whole brain evolution, the basic molecular and research, with some amazing and 16 Harnessing viruses cellular workings of the brain have often unanticipated findings. 16 The humble roundworm synergies with brains of smaller and This is discovery science, and it has simpler organisms that we can study already given us incredible advances 17 Bacteria unlock the key to in detail. By understanding them in neuroscience and beyond. A study editing the brain's DNA we understand ourselves. Second, of new medicines approved by the evolution has led to organisms that USA’s Food and Drug Administration CHAPTER 5 thrive in diverse environments: (FDA) found that every single one jellyfish that glow, perhaps as a of the 210 new medicines approved FUTURE LEAPS IN protection against predators; algae from 2010-2016 was developed from BRAIN SCIENCE that sense light, controlling their discoveries in fundamental science. 18 Big questions in brain science movement to help in photosynthesis; The benefits of discovery science are 19 Adapting on the go or bacteria that protect themselves broader than new disease treatments. against viruses by quickly slicing up Discovery science will also provide 20 How your brain makes and the invader’s DNA. Scientists are using insights into new architectures for uses energy these developments from nature as information processing and storage, 21 Can we regrow our brains? tools to study the brain. and deliver breakthroughs we can’t 22 Amazing animal abilities As you’ll find throughout this even dream of right now. In this magazine, these and many other magazine, we celebrate scientific natural innovations have had an innovations inspired by nature. CHAPTER 6 enormous impact on what we know Brains are such complex machines— IMPORTANT ISSUES IN SCIENCE about the brain, and all of them curiosity-driven research into their have one thing in common: how inner workings is sure to lead to new Ethical considerations 23 they were discovered. In each case, knowledge in health, technology and 24 Investing in science researchers—driven by curiosity other fields that don’t yet exist. rather than pressure to develop a I hope you enjoy our latest issue.
QBI.UQ.EDU.AU/NATURE-DISCOVERY The BRAIN series 1 CHAPTER 1 WHY STUDY THE BRAIN?
he brain is the complex and mysterious core of who we are: Tit determines our personalities and preferences—why we prefer chocolate over vanilla, or ballet over football—and how we think, act, move and remember. There is no question we have made some major advancements, particularly in the last 40 years. But when it comes to understanding how the brain processes information and produces outcomes, there is much still to learn and many exciting discoveries to come. Definitive answers to so many questions remain: Why do we sleep and dream? Why does dementia only affect certain people as they age? How do our brains store some memories, but discard others? What are the critical elements that affect the brain in the earliest stages of life, and can brain diseases and disorders be delayed or treated? How can we repair injured brains and nerves? What we hope to achieve by unravelling the brain’s secrets can be broadly broken down into three areas: and making new ones. Understanding to reveal how the brain processes how these unique connections are information, and understanding To understand what it is forged and modified will help us truly how each connection fits into larger 1to be human comprehend the link between the networks across the brain. physical brain, our behaviour, and You are your brain. Your brain is the what makes us individuals. To understand and treat very essence of your personality, 3brain diseases and disorders individuality and abilities. Unravelling To understand and how the brain works will help us 2enhance healthy brains Dealing with the tide of neurological understand the basis of human diseases and disorders is one of behaviour and actions. While each By exploring and mapping the the biggest challenges of our time. brain is unique, all healthy human inner workings of how a normal Neuroscience advances in the brains share the same basic structures brain functions and how it can 21st century will revolutionise health and functions. It’s the specific ways instantaneously create new thoughts, care just as the development in which our brain cells communicate learn new things and recall memories, of vaccines and antibiotics did in the that makes each of us different, we can harness that knowledge to past 200 years. To effectively treat and this is influenced by both our enhance brain function. This will brain diseases and disorders, including genetics and interactions with our require identifying and categorising dementia, schizophrenia, depression, environment. With experience, the thousands of types of brain motor neurone disease and many whether physical or emotional, our cells and their connections with one others, we need to understand how brain remodels itself, strengthening another, monitoring and recording the healthy brain functions and what and weakening existing connections their activity patterns in real time makes these processes go awry.
The most exciting part is that by studying how the brain works, we open up numerous possibilities for treating the vast range of mental and neurological
disorders prevalent in our community. WILLIAMS 2. STEPHEN SUAREZ, 1.RODRIGO ISTOCK;
2 The BRAIN series QUEENSLAND BRAIN INSTITUTE Brain basics 1.3-1.4 kg Adult brains weigh 100 billion ~1.3-1.4 kg There are around 20% The brain accounts 100 billion neurons for about 2% of the (brain cells) in the body's weight but average adult uses 20% of brain its energy
The brain has trillions of More intelligent connections species have more between brain folds as this neurons increases the area for connections 100,000 Brain tissue the size of a grain of sand has about 100,000 Folds in the neurons human brain are called sulci (grooves) and 70% The brain uses about gyri (ridges) 70% of a human’s 22,000 genes, mostly to control connections between neurons as we learn and remember
1
What's a brain 2 A-Z disorder? 3 hen the brain is operating Wnormally, all of its parts – including cells, electrical activity 1 Neurons in the hippocampus of the and chemical messengers – work brain. 2 An astrocyte, which supports together to make our bodies and neurons. 3 A Purkinje neuron, which regulates muscle movement. minds function as they should. A brain disorder is anything that Types of brain cells disrupts any of these aspects of eurons are the basic building blocks diversity, it is important to have ways of normal brain function and affects Nof the brain and the nervous system. identifying and distinguishing between quality of life. They send and receive signals, which the different types and their roles. allow us to think, form memories, move Unfortunately, this is not straightforward, our muscles and much more. but some possibilities include considering Neurons have different shapes, sizes a neuron’s shape, location, where its and functions, and while there are three branches project out to, what genes it primary types of neurons in the spinal expresses, and where its inputs begin. cord, the brain is another story. Researchers are still trying to There may be hundreds or thousands determine how to classify neurons. This of specialised types of neurons in is a fundamental step to delving even the mammalian brain. With so much deeper into how the brain operates. ISTOCK; 1.RODRIGO SUAREZ, 2. STEPHEN WILLIAMS 2. STEPHEN SUAREZ, 1.RODRIGO ISTOCK;
QBI.UQ.EDU.AU/NATURE-DISCOVERY The BRAIN series 3 Why study the brain?
Key leaps inspired by nature Our current work in neuroscience wouldn't be possible without these developments in tools, techniques and knowledge.
The nervous system has units 1Santiago Ramón y Cajal had a passion for art but followed his family into medicine. At the time, the prevailing theory was that the nervous system comprised one connected network of tissues. Using Camillo Golgi’s staining technique on microscopic 5 slides of brain cells, Cajal saw through artistic eyes what others could not: that brain tissue was made of individual cells, called neurons. This was a major shift in knowledge of the brain at the time, and Golgi and Cajal were awarded a Nobel Prize for this discovery in 1906.
4
1 Roundworms: a simple model for 4 the nervous system How neurons communicate Sydney Brenner was a geneticist whose 2 Sir Alan Hodgkin and Sir Andrew Huxley studied the neurons of squid, contemporaries included the scientific to show for the first time that signals travel along these nerve cells via luminaries James Watson and Francis Crick, electrical impulses from the movement of charged particles called ions. Sir who first described DNA’s structure as a John Eccles extended this work to explore what happens at the junction double-stranded helix. Brenner, together between two neurons, called a synapse. He showed that chemical signals with John Sulston and Bob Horvitz, turned can produce electrical currents that allow neurons to communicate. The their attention to mapping out the cells trio was awarded the Nobel Prize in 1963 for these discoveries. of a simple organism, the roundworm Caenorhabditis elegans. Their Nobel Shedding light on the visual brain Prize–winning work opened up a new way 3 David Hubel and Torsten Wiesel advanced our understanding of for scientists to study neurons, of which vision. They showed different images to cats and noted which parts of roundworms have just 302. They showed their brains were activated. They devised a way to record the activity of that some neurons are programmed to die, a single neuron and then mapped out the visual cortex of the brain. They and discovered the genes that regulate this made discoveries about how the brain processes visual information. process—which also happens in humans. Importantly, they showed there's a critical period in the early stages of This tiny worm (see p16) can regenerate life when connections of the brain can be changed, and after that, visual damaged neurons, providing a model to
pathways are set. They were awarded a Nobel Prize in 1981. understand their growth and repair. NICK VALMAS/QBI GETTY, GETTY, GETTY, COMMONS, WIKIMEIDA (CLOCKWISE): CREDITS
4 The BRAIN series QUEENSLAND BRAIN INSTITUTE Where memory is Harnessing the gene editing power of bacteria 5stored in the brain 7One of the most significant recent scientific developments has been the Only recently have scientists ability for scientists to easily target and modify DNA at specific places in the started to understand how we genome—known as gene editing. This game-changing technique, called CRISPR, remember things and where came about when Professor Jennifer Doudna and Professor Emmanuelle memories are stored in the Charpentier harnessed a natural defence that bacteria use to slice up and brain, at the level of neurons. destroy viruses that invade them. Neuroscientists are using CRISPR to alter gene Neuroscientist Eric Kandel expression by editing DNA in mammalian brains under a variety of conditions. was awarded the Nobel Prize This may one day help us treat heritable brain disorders such as Huntington's for Physiology in 2000 for his and Alzheimer’s diseases, or to treat brain diseases caused by acquired DNA work in showing that neurons mutations, such as some brain cancers. change their connections when learning occurs. Kandel used a species of sea slug, Aplysia californica, as a simple model for studying what happens to neurons as an organism learns.
7 Optogenetics - 9controlling the brain 8 Optogenetics is the process of using genetic techniques to enable light to turn cells like neurons on and off. This leap in neuroscience came 6 initially from observing proteins in green algae Lighting up the brain that control movement in 6Taking inspiration from response to light. Scientists nature, Professor Martin Chalfie genetically engineer groups wondered if the green glow of neurons they want to study of a jellyfish could be used by inserting light-sensitive to visualise cells in the body. proteins called opsins. When Following the biochemical light is shone on those isolation of green fluorescent Human genome sequenced neurons, they activate. This protein (GFP) by Osamu 8 In 2003, a 13-year project to map the kind of stimulation is much Shimomura, and mapping of whole human genome (3.2 billion base pairs more specific than using its DNA sequence by Doug of DNA) was completed. This key milestone in electrical stimulation, and can Prasher, Chalfie used GFP to science couldn’t have happened without the reveal how neurons connect visualise neurons in worms. development of Taq polymerase, an enzyme and how they contribute to Roger Tsien then developed derived from heat-loving bacteria that were different behaviours. many fluorescent proteins, first found in Yellowstone National Park’s which have been used in myriad famous geysers. The mapping of 23,000 genes ways, including to show how has enabled scientists to link particular genes neurons grow and connect. with normal brain function, and find others that Chalfie, Shimomura, and Tsien play a role in brain diseases and disorders. were recognised with the 2008 Nobel Prize in Chemistry for their
CREDITS (CLOCKWISE): WIKIMEIDA COMMONS, GETTY, GETTY, GETTY, NICK VALMAS/QBI NICK VALMAS/QBI GETTY, GETTY, GETTY, COMMONS, WIKIMEIDA (CLOCKWISE): CREDITS transformational work.
QBI.UQ.EDU.AU/NATURE-DISCOVERY The BRAIN series 5 Why study the brain?
The state of neuroscience today
n 1980, Nobel Prize–winner Sydney amazing advances (see p4) have systems known, and there are many Brenner said: "Progress in science been propelled by scientists who important functions that remain Idepends on new techniques, new are inspired by nature and connect a mystery, such as how memory discoveries and new ideas, probably seemingly unrelated discoveries to is stored, how the brain processes in that order." open new fields of brain research. information, how many types of Despite decades of study, the Nobel laureates Sydney Brenner and neurons exist, and why people limited ability to peer inside a living, Eric Kandel, for instance, recognised develop brain diseases like dementia. working brain has meant that the importance of studying simple Today, with cutting-edge, neuroscientists must continually animals to provide a deeper nature-inspired technologies, we develop new technologies to progress understanding of the human brain. are entering an accelerated era of what we know. Kandel used the California sea hare, discovery about the brain. Scientists Key milestones in understanding A. californica, to study memory, and can now look at the cells inside a the brain include early observations Brenner used the roundworm C. living brain, control the actions of made by the 4th century Greek elegans to study genetics. specific cells with light, and correct philosopher Hippocrates, who The study of the nervous systems errors in the cells responsible for believed the brain to be responsible of simple organisms like roundworms, brain function. Many big questions for intelligence; the amazing drawings and the behaviour of fruit flies, will be answered by scientists who of individual brains cells in the bees, sea slugs, and other animals, turn to nature for inspiration. early 1900s by Cajal, who was able has taught us much about how to identify them thanks to Golgi’s they sleep, see, fly and navigate. Some big questions include: staining technique; and the discovery Harnessing animals' evolutionary • Ho w does the brain encode and of how brain cells talk to each other specialisations has expanded our process information? through chemical signalling in nerve toolbox for neuroscience research— • How is memory stored? cells of animals, by Nobel Prize- for instance, using the glow of a • Ho w do our brains adapt in real time winning Australian neuroscientist Sir jellyfish to light up brain cells. to experiences? John Eccles and colleagues. • Ho w does the brain use energy? The next leaps • How are our brains so efficient? Explosion of neuroscience Although we've made real progress, • What is consciousness? An explosion in our understanding of there is still much to learn. The • Can we regrow or repair our brains? the brain has come in the last 40 or so brain is among the most complex • Can we treat or cure brain diseases? years, and has been accelerating at an unprecedented pace as technology Our brains are the most complex systems on Earth and there
rapidly improves. Importantly, these are many important functions that remain a mystery... ISTOCK CREDITS:
6 The BRAIN series QUEENSLAND BRAIN INSTITUTE CHAPTER 2 ANIMAL INSPIRATION
hough humans are most better understand sensory processing, inspiration for developments in genetically similar to such as how animals see colour and new technology. Take, for instance, Tprimates, with 98 per cent of make sense of visual information; the ability of the mantis shrimp to the same genes, we nevertheless we can learn how animals navigate see polarised light, which humans share many of our genes with the their environment, including through cannot detect without special simplest of organisms—about flight; and by looking at how animals glasses. Scientists are now working 61 per cent with fruit flies, for sleep, we can learn more about our on an underwater navigation example. Despite differences in own sleep behaviours. All of these technique using this process. size and complexity between the animal models and behaviours give us Likewise, understanding how birds human brain and smaller animal important insights into understanding fly in flocks without colliding can brains, the similarities mean that the human brain. help us fly groups of drones or much can be learned from studying As with all discoveries, animal develop better crash-avoidance these simpler models. We can research can also be a source of systems for aircraft. CREDITS: ISTOCK CREDITS: Animal inspiration
Flight: learning from nature's best honeybee can return home research has revealed that budgies are which birds evolved millions of years quickly and precisely after very body aware: while flying through ago, has also been adopted by aircraft Aflying several kilometres from a narrow space, they close their wings pilots to avoid collisions. its hive to find food. A budgie can in advance, but only when the space Combining biology, neuroscience fly rapidly through a dense thicket, is narrower than their wingspan. and engineering, Emeritus Professor avoiding all the branches. How do They also found that budgies flying Srinivasan’s team has designed new these tiny-brained creatures navigate head-on toward each other avoid vision systems to guide the flight so well? How do they avoid collisions? collisions by using a simple rule: each of autonomous aircraft like drones, These are just some of questions that bird veers to its right. This strategy, so they can avoid collisions with Emeritus Professor Srini Srinivasan other aircraft or obstacles in their from UQ’s Queensland Brain Institute environment. has been trying to answer. “We are gaining new knowledge His team has uncovered how bees about how small animals with are able to fly safely through narrow relatively simple nervous systems passages, regulate their flight speed, have evolved elegant strategies for gauge how far they have flown, and guidance and navigation, and are orchestrate smooth, safe landings. incorporating the findings into new More recently, their research has technology,” he says. shown how bees flying in swarms can make coordinated turns to move safely in busy air spaces and avoid collisions with each other. “Bees are very smart,” says Emeritus Professor Srinivasan. “They can learn colours, shapes and smells, detect camouflaged objects, and even fly through complex mazes.” His team also studies how flying
creatures avoid obstacles. Their GETTY CREDITS:
8 The BRAIN series QUEENSLAND BRAIN INSTITUTE Flies sleep like babies
ny animal with a brain sleeps. the flies are sleep deprived, they sleep ASome sleep more than others, but longer and more deeply to catch up. surprisingly, the amount of sleep they Associate Professor Bruno van need is not related to their body size or Swinderen's team at UQ's Queensland brain size. Fruit flies, for instance, have Brain Institute are studying fruit flies sleep patterns that are remarkably similar to further understand which genes are to humans—they sleep mostly at night important for regulating sleep, why we for about 8 to 10 hours, have a midday sleep, what triggers sleep, and what siesta, sleep more when they are young, causes sleep disorders. They are also and sleep in stages of varying intensity, investigating the roles that different such as deeper and lighter sleep, just as stages of sleep have in how the brain humans do. Furthermore, fruit fly sleep functions. These insights may also help is affected by the same stimulants and us understand the mechanisms that sedatives that work on humans, and if support consciousness.
Sleep hours in a day 0 2 4 6 8 10 12 14 16 18
Elderly Adult Baby human human human
Horse Elephant Guppy Dog Fly Tiger Python
The evolution of sleep Ancient cellular sleep functions have been preserved through evolution and in more complex organisms, occur during specific sleep stages. Different sleep functions have developed for organisms with more complex brains, including having different stages of sleep. Sleep-like state for regulating stress and development Full sleep state with sleep switch No sleep
mammals
fish sponges birds
reptiles molluscs
jellyfish flies nematodes
Awake Asleep Awake Asleep Awake Asleep
Electricial recordings from neurons
No brain, Central nervous system, Simple brain, Complex brain,
CREDITS: GETTY CREDITS: simple learning learning via association selective attention consciousness
Increasing brain complexity Animal inspiration
Animal vision: seeing through different eyes
aking sense of all the visual information we receive Mevery second we're awake uses about a quarter of the brain's processing power at any one time. The human eye, our primary sensory organ and source of information, is often seen as highly advanced, so it might be surprising to learn that we may have only a quarter of the colour vision capability of a mantis shrimp and are at least six times slower in visual reaction time than a fly. Mantis shrimp have the most complex retinal visual system known to science, says Professor Justin Marshall, from UQ's Queensland Brain Institute, an expert in animal vision. The crustaceans use polarised light for attracting a mate, with only males reflecting this light. Mantis shrimp also see colour and have 12 input channels, or sensitivities, in their eyes for this. Humans only have red, green and blue, and yet we can distinguish millions of different colours. "How mantis shrimps use colour remains shrouded in mystery," says Professor Marshall, whose research has uncovered these amazing findings. "At the moment, we understand more about how their vision system works than how they use it. There is a lot of exciting research to come." Navigating underwater, Many animals out-perform humans in some form of vision and some, thanks to mantis shrimp including the octopus, can see lobal positioning systems (GPS) are octopuses, which forms of light that humans cannot. Gso commonly used now that most communicate using Octopuses also see polarised light, fitness trackers and smart watches polarised light. The a form of light that humans only see have them embedded. But while scientists have built with the aid of sunglasses and other GPS can be accurate on land, under polarisation sensors that can determine the ocean it’s a different story. “Most the sun’s position in the sky, based on optical devices. Surprisingly, they modern navigation techniques don’t patterns of light underwater. are also completely colour-blind and work underwater,” says Dr Samuel This new method will enable more seem to have swapped colour for Powell from the Marshall lab at UQ’s accurate and cost-effective long- polarised information from the world Queensland Brain Institute. “Satellite- distance navigation, and could enable around them. How do they manage based GPS, for example, only works to navigation at depths up to 200 metres their feats of amazing camouflage, a depth of about 20 cm.” below the ocean’s surface, ideal for blending perfectly with the ocean Dr Powell and colleagues are submarines or submersibles used in devising a new technology to extend exploration and recovery. “Our method navigation capabilities underwater, would allow for real-time navigation …many animals out- taking inspiration from marine underwater with more accurate long- animals including mantis shrimp and distance results, without the need to perform humans in some cephalopods like squid, cuttlefish and resurface periodically,” says Dr Powell.
form of vision… ODONTODACTYLUS MARSHALL LAB/QBI, GETTY, CREDITS: MARSHALL/QBI JUSTIN CALDWELL, / ROY HAVANENSIS
10 The BRAIN series QUEENSLAND BRAIN INSTITUTE floor? And why do some, such as the blue-ringed octopus, use colours they don’t see themselves? These cephalopods are very sensitive to contrast patterns and even the texture of their surrounds; they can mimic their environment almost perfectly and have evolved to ‘know’ the colour of the ocean bed. The iridescent blue of the tiny blue-ringed octopus is likely there to warn animals that can Among the vertebrates, even the Studying how these small-brained see colour that its bite is laden with goldfish with its tiny brain can detect animals can see and process potentially lethal toxins. more colours than a human, and it such complex visual information "Instead of colour, cephalopods can see ultraviolet (UV) wavelengths, helps us understand more about have developed polarisation vision for a range of light that humans cannot how our brains process our visual tasks that mostly remain obscure to normally see. Many reef fish, birds, world. Scientists, inspired by this us," says Professor Marshall. "Some lizards and mantis shrimp use UV vision in nature, are also working certainly communicate with polarised light, some for covert communication on developing better underwater light but the meanings of those among themselves, most likely for navigation and camera technologies. messages are yet to be decoded.” attracting and choosing mates. (See box, opposite).
These are the colour channels present in the visual systems of these animals—in other words, Colour vision the colours on the spectrum that their eyes see.
Stomatopod
Bird
Bee
Reef fish
Human
Dog
Octopus
300 400 500 600 700 UV CHAPTER 3 LIGHTING UP THE BRAIN
ecause the brain is protected in our skulls, it is not easy A truly remarkable development, from a seemingly to study its inner workings. Neuroscientists have relied obscure source, was harnessing the fluorescent glow of Bon recording electrical signals, as well as looking through animals like jellyfish to light up everything, from whole microscopes at stained cells. As advancements in technology animals to individual brain cells. Fluorescence can help have progressed, particularly with imaging techniques like us see some of the smallest molecules inside cells as they MRI, PET and CT scans, scientists have been able to visualise move around to make brain cells work. Scientists can also more of the brain. But while those scans show the brain’s see how neurons talk to each other and how they repair anatomy, blood flow and coarse-grained activity, they don’t themselves after injury. This allows us to understand more provide any insights into how individual neurons or small about how the brain works, how we learn and remember, networks of neurons communicate. and why disorders and diseases occur.
How the humble jellyfish revolutionised brain science
ften in science, being individual cells in other organisms. curious and asking simple At the time, Professor Chalfie was Oquestions can lead to amazing using the tiny roundworm C. elegans discoveries. One such story began (see p16) to study how nerve cells in the 1960s with a scientist, Osamu worked. In a groundbreaking study, Shimomura, asking the question: what he successfully labelled groups of makes a jellyfish glow? Shimomura connected neurons in roundworms, was able to identify the particular and a new era in visualising nervous protein—which he called green system cells began. fluorescent protein (GFP)—from Scientists then used GFP to make the jellyfishAequorea victoria that all kinds of cells glow, from neurons produced its bioluminescent light. to plant cells. But the glow didn’t last
Years later, Professor Martin Chalfie that long, and green wasn’t always The beach scene that Roger Tsien's lab created heard about GFP and wondered if the most ideal colour to work with. with different variations of bioengineered jellyfish genes grown in bacteria. this protein could be used to highlight Enter biochemist Roger Tsien, who QBI WIKIMEDIA COMMONS, GETTY, CREDITS:
12 The BRAIN series QUEENSLAND BRAIN INSTITUTE Neurons are lit up with GFP (green A visual representation fluorescent protein), which was of the movements of derived from a jellyfish. molecules inside neurons at the point where they connect with other Lighting up the neurons. tiniest part of cells ne of the more exciting Odevelopments in neuroscience is using a fluorescent protein from the lobed cactus coral Lobophyllia hemprichii An example of a 'brainbow', where to highlight the workings different neurons are visualised inside a brain cell in real time. Using a highly with coloured fluorescent proteins. sensitive super-resolution microscope to highlight important molecules that transmit signals at the junction (called a synapse) between neurons, Professor Frederic Meunier and his team at UQ’s Queensland Brain Institute have been able to reveal what happens inside living nerve cells. “We can now see molecules organise themselves in real time, viewing the nitty gritty mechanisms that allow neurons to communicate,” says Professor Meunier. “You see molecules moving randomly and then, for a few milliseconds, interacting with each other.” “This is an exciting time, as we’ve opened the door for many more groundbreaking studies that will change our view of how molecules function to make the brain work. This work could further our understanding of memory, learning and neurodegenerative diseases,” he says.
set about improving the brightness of GFP, as well as genetically engineering Using a jellyfish to light up the brain it to express more colours. He also isolated fluorescent proteins from Insert into a virus shell with other animals, to develop a broader 1 3 code to target neurons range of colours. To showcase the array of colours, members of his team Put into a created a multicoloured beach scene (mouse) with bacteria in a petri dish. brain to The use of GFP and other glowing target proteins to light up the inner workings neurons of organisms has revolutionised neuroscience. Before this, scientists weren’t able to see such detail. In brain research, GFP and other proteins have been used to visualise different neurons, to show how Fuse known code Visualise to see the neurons networks form in the brain, to identify 2 for mouse and 4 of interest individual neurons in slices of the jellyfish DNA brain, to study how neurons grow and connect, and to mark neurons affected by plaques that are hallmarks of Alzheimer’s disease. For their transformational work that began with a question about glowing jellyfish, all three scientists were recognised with
CREDITS: GETTY, WIKIMEDIA COMMONS, QBI QBI WIKIMEDIA COMMONS, GETTY, CREDITS: the Nobel Prize in Chemistry in 2008.
QBI.UQ.EDU.AU/NATURE-DISCOVERY The BRAIN series 13 CHAPTER 4 CONTROLLING THE BRAIN
o understand how the brain works at the most basic level, Tneuroscientists need to record the activity of neurons to study how the brain processes information. The next step is to control or alter cells in animal models at will, so we can see and understand the impacts of those changes. Some of the more exciting developments in neuroscience are using ideas from nature to advance our understanding of brain function, such as light-sensitive proteins from algae, defence mechanisms from bacteria, and cargo delivery via viruses.
ur brains are constantly A change in the concentration of Switching on brain cells at will receiving information from all calcium ions is a way of tracking To go one step further than recording Oaround us via our senses, and the activity of neurons. By tracking brain cell activity, Professor generating movements that help us calcium, it is now possible to measure Williams and his team have used a execute our goals. But our brains also thousands of individual cells in animals revolutionary light-based technique have a rich repertoire of internally as they execute specific actions. called optogenetics to study how generated activity—our emotions, Neuroscientists are using a these circuits process information. imaginings and memories—that isn’t cutting-edge technology called For this technique, scientists triggered by what we just heard or two-photon imaging microscopy genetically engineer channels in saw, or the next movement we want to measure these changes. At UQ’s a neuron to respond to light, by to make. How does the brain achieve Queensland Brain Institute, Professor inserting a light-sensitive protein this? By what logic do those millions Stephen Williams and his team use derived from algae (see opposite). and millions of neurons work together this technique to explore the way When a channel is exposed to light of to create a thought, or to convert that dendrites, the fine branch-like a particular wavelength, say blue, it these black squiggles into meaningful extensions of neurons, process opens to let ions pass into the neuron words and sentences, or to hit a cross- information in the brain. They have to generate an electrical signal. court forehand? This is a big question pinpointed that active dendritic Flashing a light can trigger or inhibit in neuroscience, and to answer it, information processing is important neurons expressing light-activated scientists must track brain activity at in brain circuits that are activated at channels with amazing accuracy. the level of individual cells. the moment an animal is engaged Using this technique, Professor A new approach is to measure in a task. The mammalian brain is so Williams’ team has been able to calcium, a key ion involved in a complex that to narrow down neurons identify a system of neurons that were range of critical processes in the from the approximately 70 million active when animals were engaging body, from contracting our muscles, in a mouse brain, to just a single in a task. This 'cholinergic system' to cell growth, memory formation, group—and link it to a behaviour—is is disrupted in diseases of the brain and sending signals along neurons. an incredible advance. that impact cognitive abilities, such as dementia, so future research may ... it is now possible to measure thousands of individual reveal ways to stop this disruption and brain cells in animals as they execute specific actions... slow the progression of brain diseases. MAREK/QBI ROGER GETTY, SCOTT/QBI, ETHAN GETTY, CREDITS:
14 The BRAIN series QUEENSLAND BRAIN INSTITUTE The whole brain o understand how neurons with appropriate behaviours. Twork together to process His team studies the tiny information, scientists can transparent zebrafish, peering monitor how connected into its simple brain using a groups of neurons across the cutting-edge technology called brain activate in response light-sheet microscopy to show to a stimulus. Advances in nearly all of the neurons in their technology have only recently brains at once. enabled researchers to see the To understand how zebrafish activity of networks of neurons make sense of their world, in live animals, in real time. “It the team records brain-wide has always been hard to study activity while presenting these networks, because you images, sound, and motion have to observe the activity of stimuli to the fish. Each stimulus thousands of neurons at the activates different neurons, same time,” says Associate so the scientists can see how Professor Ethan Scott, from different networks are engaged UQ’s Queensland Brain Institute. to process those stimuli. His work focuses on the circuits The scientists can then use and networks of neurons optogenetics (see below) to responsible for animals’ ability stimulate neurons with light to sense the world and respond in very precise ways. They can customise the light patterns projected into the animals’ brains, like a hologram, activating the exact neurons they think are responsible for visual, auditory, and vestibular Different types of neurons are lit up processing (balance) and in the brain of a zebrafish. studying the fishes’ responses. Right: zebrafish swimming.
How optogenetics works
Take gene for 1 light-sensitive 4 Shine blue light on mouse protein
2 Integrate into a virus shell
Blue light Algae controls the brain ho’d have thought that a Whumble slimy algae could progress the next revolution in neuroscience? In the 1990s, scientists observed that electrical signalling Ions in cells of green algae changed in response to light. That kernel of knowledge was used to isolate the 5 Record light-sensitive gene that has opened electrical up a new field in neuroscience activity of research, called optogenetics: using neurons light to control the activity of brain 3 Insert into rodent brain cells in living tissue. CREDITS: GETTY, ETHAN SCOTT/QBI, GETTY, ROGER MAREK/QBI ROGER GETTY, SCOTT/QBI, ETHAN GETTY, CREDITS:
QBI.UQ.EDU.AU/NATURE-DISCOVERY The BRAIN series 15 Controlling the brain
This roundworm (C. elegans) has had a neuron severed with a laser, and a new extension bridges the gap.
Harnessing viruses to repair damaged nerve cells
n the late 1990s, biologists understand how to repair the long, Professor Andrew Fire and cable-like axons of nerve cells, The humble roundworm: a IProfessor Craig Mello were studying which can be damaged by trauma or key player in brain science how genes are expressed, or turned degraded in many brain diseases. on, when they made a remarkable A main challenge has been the discovery about DNA’s single-strand delivery method: how do you get cousin, ribonucleic acid (RNA). these small interfering RNAs into the At the time, it was already well right cells at the right time? For this, known that genes contain the researchers have had help from some instructions for making specific unexpected allies in nature: viruses. proteins—the building blocks of the Decades of research into infectious body’s cells and their functions—and viruses, such as HIV and the herpes that messenger RNA relays those simplex virus, has revealed these instructions to the protein-making viruses can be co-opted to deliver regions of the cell. Professors Fire genetic material into human cells. and Mello and their colleagues found By removing all the harmful genetic he tiny C. elegans, measuring that by exposing cells to an artificial information and leaving the virus shell, Tabout 1 mm long, has done more double-stranded RNA of a specific scientists have effectively turned these for neuroscience than just about any gene, it can interfere with, and viruses into tiny cargo containers that other organism. With just 302 neurons destroy, the normal messenger RNA can deliver synthetic DNA or RNA. and 7000 connections, it has a much simpler nervous system than our of that gene. This process is called Viruses can be made to target complex 100 billion neurons. Professor RNA interference (RNAi) and allows specific cell types at certain times, Hilliard's team has been able to slice scientists to silence specific genes allowing, for example, the delivery of the axon of a single neuron to see as needed. Importantly, Professor RNA to brain cells undergoing repair how C. elegans repairs it. They found Gary Ruvkun and Professor Victor in a particular part of the brain. These it is able to spontaneously repair a Ambros discovered that cells in C. technologies have now become broken nerve by stitching the two elegans also use a similar mechanism, indispensable research tools. halves back together! (See image above). If we can figure out at the via tiny pieces of RNA (microRNA), Associate Professor Tim Bredy is most basic level the signals and to turn off specific genes. At UQ's using virally delivered RNA to try proteins used in that process, we may Queensland Brain Institute, Professor to enhance memory, and Professor be able to apply that to humans to Massimo Hilliard and his team are Jürgen Götz is using the technique to help repair nerve damage.
using RNAi in C. elegans to help find new treatments for dementia. SCIENCEPHOTO ISTOCK, HO/QBI, YAN XUE CREDITS:
16 The BRAIN series QUEENSLAND BRAIN INSTITUTE Tiny worm could hold the key to repairing Bacteria injured nerve cells unlock the key to editing the brain’s DNA ust like many other discoveries, Jthis great advance in neuroscience happened serendipitously in the late 2000s when Professor Jennifer Doudna and Professor Emmanuelle he ability to reconnect nerve Charpentier took interest in the clever cells following an injury is a defence strategies used by bacteria to Thuge goal in science. Humans destroy viruses and other invaders. The cannot do this spontaneously and scientists noted that bacteria, such as it's why damage to the spinal cord is E. coli, and common ‘good’ bacteria in usually permanent. yoghurt, were able to chop up viruses But this ability does exist in nature: with molecular scissors and destroy a number of invertebrate species, their harmful DNA. This curiosity-driven like the microscopic roundworm discovery has enabled scientists to fight Caenorhabditis elegans, are able to against the new coronavirus, where new re-fuse and restore the function of tools are being developed to detect the neurons that have been severed. virus and ward it off. Professor Massimo Hilliard and Translating this idea to neuroscience, his team at UQ's Queensland Brain researchers suspected they may be Institute are studying this amazing able to use the bacteria’s molecular capability in C. elegans in the hope scissors to slice up of one day being able to treat nerve specific sections of injuries, such as paralysis, in people. DNA in animals, They uncovered key information on including humans, how this process is regulated. Neurons and that the cell’s communicate using lengthy, cable- natural DNA repair like structures called axons. In 2015, mechanisms would Professor Hilliard's team discovered lead to changes in the ability of C. elegans to carry out DNA sequence. This powerful gene- a process called axonal fusion, where editing technology, called CRISPR, gives two halves of a cut axon reconnect. researchers the ability to edit parts of “It’s a very efficient process,” the genome, targeting specific regions Professor Hilliard says. “Instead of of interest, like genes that are involved injured nerves having to regrow the in brain development, or genes linked full length to their targets, they are to brain diseases such as dementia or basically just bridging a gap to rejoin Huntington's disease. the nerve and allow it to function Neuroscientists can also use CRISPR again.” (see image, opposite top). to disrupt healthy genes that, when To undergo fusion, the axon still altered, might cause disease. This attached to the cell must first regrow, technique can create disease models then position itself in close proximity that help us understand conditions to its separated axonal fragment. such as Alzheimer’s disease and motor Once the two parts of the axon neurone disease. CRISPR also offers the have reconnected, they fuse their hope of repairing or changing disease- membranes to form a cohesive whole causing genes. with an outer membrane and the inner The challenge is to find which genes material of the cell. are linked to brain development It’s a process that offers promise as and diseases, to target them. Some a potential treatment for people with conditions will be more suitable for nerve injuries, which can cause life- this approach than others; in the
CREDITS: XUE YAN HO/QBI, ISTOCK, SCIENCEPHOTO ISTOCK, HO/QBI, YAN XUE CREDITS: long disabilities. case of disorders like depression or schizophrenia, dozens of genes may contribute to the onset. CHAPTER 5 FUTURE LEAPS IN BRAIN SCIENCE
e have discovered more about the brain in the change, and can adapt to experiences to store memories last 50 years than in the previous 500 years. We and learn, as well as adapt to damage. We have learnt Whave learnt, for example, that certain regions in that electricity and chemical signals are how neurons the brain are associated with particular parts of the body communicate with each other. or with particular skills, such as language. We have learnt In this chapter, we look at some of the big questions that individual cells called neurons are the fundamental in neuroscience yet to be answered, as well as some units of the brain. We have learnt that our brains can interesting potential applications.
Big questions in brain science
How does your How does the brain make and use brain change in energy? real time?
Can we What are the causes regrow parts of brain diseases and disorders? of our brain? How do neurons encode and process information?
How are memories formed, stored and retrieved? Why do we dream?
How does the brain adapt to experience? What and where is consciousness?
How many types of neurons are there and what are their functions? CREDITS: GETTY, QBI, SCIENCE PHOTO QBI, SCIENCE GETTY, CREDITS:
18 The BRAIN series QUEENSLAND BRAIN INSTITUTE A water flea's normal body (right) and a water flea after being explosed to a predator (left) and inheriting a protective horn.
But how is a gene turned up or down after an experience? The answer is by reversibly modifying our DNA. Back in the early 1970s, Russian scientist Professor Boris Vanyushin was studying how learning affects DNA. He found that an increase in chemical tags, called methyl groups, Adapting on the go: that bind directly to DNA was related to the strength of memory. This major the mysterious ways discovery changed the way we think about the relationship between our of epigenetics DNA and experience. We now know that, like a dimmer he DNA code in genes epigenetic change in response to an switch, these tags on DNA can turn inherited from our parents environment, which doesn’t involve a genes up or down depending on the Tgives instructions for much change in the underlying DNA code. circumstance. This was a turning point of the way our physical bodies are Professor Oded Rechavi’s lab at in neuroscience because it revealed made, our risk factors for diseases, Tel Aviv University studies these that our DNA is not our destiny and our personalities, and individual mechanisms in the roundworm implies that our environment can directions for cells to develop into C. elegans (see p16). Their earlier profoundly affect the way our brains particular types—neurons, for work showed that epigenetic changes function, all the way down to our example. But our environment and in worms can produce adaptations genes—and these adaptations can be experiences also have an impact across generations. More recently, passed on to the next generation. on how our bodies and brains they discovered that epigenetic For the past two decades, Associate look and work. The concept that a changes in neurons affect the Professor Timothy Bredy and his gene’s function can be altered by ability of the worm’s offspring and team from UQ’S Queensland Brain experience—by turning it up or down descendants to forage for food. Institute have been investigating how without changing the underlying epigenetics affects memory. They DNA code—is called epigenetics. From simple organisms to the have shown that all four DNA bases of Studies on water fleas have complex human brain the genetic code—A, T, G and C—are demonstrated this epigenetic effect. Researchers are now moving from subject to these chemical tags and These insects grew horns on their studying epigenetics in simple can work together to influence the heads in response to predatory organisms to looking at the complex strength of different kinds of memory. signals in the water and would pass human brain. Epigenetics in the brain, The team has also found underlying these features on to their offspring in principle, changes gene activity in ways in which these tags emerge, as long as the signal was in their response to a variety of experiences, showing that a large part of our environment. As soon as the signals including exposure to drugs of abuse genome doesn’t actively code for were gone, the next generation of or environmental toxins, changes in proteins that make our neurons offspring were born with normal nutritional factors, and simple daily function correctly, but is instead a heads. This is a classic example of an events such as social contact. sophisticated surveillance system that allows the environment to influence This was a very important moment in neuroscience our genes. Their work has important implications for understanding how because it revealed that our DNA is not our destiny and memory works and developing new implies that our environment can profoundly affect the treatments for fear-related anxiety
CREDITS: GETTY, QBI, SCIENCE PHOTO QBI, SCIENCE GETTY, CREDITS: way our brains function disorders like PTSD.
QBI.UQ.EDU.AU/NATURE-DISCOVERY The BRAIN series 19 Future leaps in brain science
A mitochondrion, seen by coloured transmission electron micrograph (TEM). Mitochondria are found inside cells and are the energy powerhouses.
Dr Steven Zuryn, Queensland Brain Institute, UQ am driven Iby curiosity and the thrill of uncovering a hidden piece of nature that's billions of years in the making. By focusing on mitochondria, I want to discover how cells fundamentally interact with their own internal powerhouses. From a biological point of view, it is mitochondria that have Food for thought: how your literally powered the explosion of evolution and complex life which brain makes and uses energy is energetically demanding, resulting in the diverse array of our brain is arguably the some stage, an ancestor of our species we see around us, both hungriest organ in the body, cells fused with one of them. After plant and animal. They need Yconsuming roughly 20 per cent all this time, mitochondria still our cells and our cells need of your energy each day. have their own genome. It’s much them. However, mitochondria Most of that energy is produced smaller than our main genome, and can deteriorate as we age. by tiny structures inside cells called encodes just 37 genes. But each This is why mitochondrial mitochondria, which break down mitochondrion has as many as 10 dysfunction lies at the core complex carbohydrates from our food copies of its genome, and each cell of many human diseases, into simple sugars. contains hundreds to thousands of including inherited mitochondrial “Considering the brain is made up of mitochondria. Consequently, changes diseases and possibly more around 100 billion neurons, that gives in mitochondrial DNA can have a big common age-related diseases you an idea of how much energy the effect on the body. such as dementias and cancer. brain uses and needs to survive, and “We now know that there are Understanding how cells can the mitochondria are responsible for more than 30 diseases caused by adapt and repair mitochondria is important for improving that,” says Dr Steven Zuryn from UQ’s mitochondrial DNA mutations,” says outcomes for people with Queensland Brain Institute. Dr Zuryn. He wants to understand mitochondria-related disorders. Intriguingly, much of what we know how mutations in mitochondrial The next frontier is to about mitochondria originated with DNA change in individual cells and understand the nanoscopic the study of bacterial evolution. throughout the entire body during mechanics of how this Until around two billion years a lifetime. His research is focused on occurs and identify possible ago, mitochondria were separate understanding how these mutations interventions to prevent organisms, much like bacteria. At are passed on, or prevented from mitochondrial damage, or being passed on, from one generation improve damage repair, so “We now know that there to the next. that we can treat disease and, Such explorations could provide are more than 30 diseases ultimately, prolong cell and insight into degenerative brain neuron function in the face of caused by mitochondrial diseases, which have been linked with ageing and disease.
DNA mutations" mitochondrial DNA mutations. QBI LAB, JAVERI PHOTO, SCIENCE CREDITS:
20 The BRAIN series QUEENSLAND BRAIN INSTITUTE Newly generated twin neurons in the adult amygdala. Dr Jhaveri and her team showed for the first time that newborn neurons are found in the adult amygdala, a brain region important for emotions and fear learning.
Can we regrow our brains?
or years, the dominant theory on shows that new neurons also form in Fthe brain’s adaptiveness held that the amygdala, a brain structure central Dr Dhanisha Jhaveri, because the connections were so to emotional processing, and can Queensland Brain complex, they would be impossible integrate into existing brain circuits. to replace once formed. In the 1960s, Intriguingly, they discovered that Institute, UQ however, the first clues about the chronic stress disrupts this process hat really brain’s plasticity began to emerge. and leads to anxiety behaviour in Wmotivates “Joseph Altman showed that new mice. The finding suggests that the me is the fact cells are made in the brains of adult formation of new neurons and their that we have rats,” says Dr Dhanisha Jhaveri, a correct connectivity is important to gone into an senior scientist at UQ’s Queensland healthy brain function. uncharted Brain Institute. Though these early From such curiosity-driven research territory, results were controversial, they were also comes the promise of new opened up followed by an explosion of research treatment avenues. some new doors and there is in subsequent decades, including “Understanding how new neurons a whole new world out there pioneering work by the Institute's form connections could lead to new yet to be discovered. I'm really driven by understanding the founding director, Emeritus anti-depressants or new anti-anxiety fundamental brain mechanisms Professor Perry Bartlett. medications,” says Dr Jhaveri. It that contribute to our cognition “The studies showed that stem cells could also reveal ways to encourage and emotion: production of reside in the adult mouse brain, and brain repair after injury or to reduce new nerve cells, how they are under the right environmental stimuli, the effects of neurodegenerative connected, how their activity is these cells will divide and form conditions like dementia or regulated and how they impact neurons,” says Dr Jhaveri. Parkinson's disease. behaviour. More recently, studies of the Could we ever regrow a whole We require this understanding hippocampus, a part of the brain new brain? Perhaps, says Dr Jhaveri, before we can rationalise and critical for memory, suggest that as but it won’t be as useful as you devise a design or a strategy many as 700 new neurons are added might think. “Instead of regrowing that will help to fix the cells or to this region each day. the whole brain, it will be more the circuits in neurodegenerative Dr Jhaveri’s research, in important to regenerate the right diseases or in cases like anxiety collaboration with Emeritus Professor kind of neurons in the right place or depression.
CREDITS: SCIENCE PHOTO, JAVERI LAB, QBI LAB, JAVERI PHOTO, SCIENCE CREDITS: Bartlett and Professor Pankaj Sah, that make the right connections.”
QBI.UQ.EDU.AU/NATURE-DISCOVERY The BRAIN series 21 Future leaps in brain science
One day we could harness these amazing animal abilities ome animal brains achieve amazing feats like regrowing How do animals tails and limbs and sensing electricity. Neuroscientists regrow tails, limbs Sare working to figure out how they do it to inspire future technologies that can apply to humans. and parts of brains? he ability to regrow whole tails and Tlimbs, and other organs, is limited mostly to worms, echinoderms like starfish, some lizards, and amphibians like newts and salamanders. The axolotl, a salamander, can regrow its legs, lower jaw, tail, large parts of its brain and heart, as well as organs such as the pancreas and kidney. It somehow turns on a process that only usually happens within an embryo. Scientists like Professor Elly Tanaka from the Research Institute of Molecular Pathology in Vienna, Austria, who studies regeneration, are trying to understand which cells regenerate a missing body part and how animals regrow only the missing part. In 2018 the entire genome of the axolotl was sequenced, providing a genetic map that will help unlock which genes are involved in regeneration. One day, humans may be able to regrow missing limbs or reconnect damaged cells in the brain and spinal cord.
How do animals sense electricity? Octopus intelligence lthough closely related to snails and slugs, octopuses Ashow a level of unusual intelligence, setting them apart among the invertebrates. In some respects they are smarter than many mammals, able to perform tasks that would baffle a dog and display more cognitive capability than a cat. Octopuses have been known to grab coconut shells to protect themselves from a shark attack, solve mazes, plan notorious escapes from aquariums and devise creative solutions to getting food or being hunted. Many of the neurons an octopus uses to process information are in its tentacles, in addition to having a centralised brain. Neuroscientists can learn a lot from octopuses, including understanding neural networks, as well as investigating how camouflage could be applied for military use. harks, rays and eels are well known for being able to detect Selectricity, but platypuses, echidnas and bees can do the same. These animals have receptors called ampullae of Lorenzini, which detect electrical currents via pores on their snouts. Animals use electroreception for locating objects around them, often prey, and typically live in environments that are low light – murky rivers, deep in the ocean, or in caves. Some fish even communicate using weak electrical signals, for attracting mates. If this could be harnessed in humans, it could enable the development of electrical interface devices to connect our brains to computers for cognitive enhancement or for augmented reality. CREDITS: GETTY, ISTOCK GETTY, CREDITS:
22 The BRAIN series QUEENSLAND BRAIN INSTITUTE CHAPTER 6 IMPORTANT ISSUES IN SCIENCE
A question of ethics xciting developments in brain Alternate use—or misuse—of science, inspired by nature, neuroscience technology Eare rapidly advancing our While scientific advances may have understanding of the brain. This the noblest of intentions, there will science is important, but, as with all always be the potential for misuse, advancements, there are significant or uses that were not originally ethical implications, and we need considered. to consider the ways in which Brain augmentation technology neuroscience technologies and designed to treat brain dysfunction discoveries are managed and used. —memory enhancement, for instance—may be applied in military Unknown consequences settings to boost soldiers’ capabilities. One of the most significant leaps in Gene editing technology has already neuroscience—using gene-editing gone a step too far in the eyes of technology to alter DNA in neurons many. For example, in 2018, a Chinese (see p17)—has the exciting potential researcher announced, to the great to cure genetic brain diseases like concern of scientists around the Huntington’s. But there are potential world, that he used CRISPR to create unknown effects of making changes to the first gene-edited babies. The a person’s genome that may manifest babies, purportedly had resistance to decades later. Other considerations HIV, but they may also have genetic include whether to make pre-emptive mutations that are life-shortening. changes in an individual’s genome if they might be at high risk of Manipulating the brain developing a brain disorder. Using Scientists can use light to control and bacteria and virus shells to deliver alter neurons, and can use techniques genetic material (see p15) also has and devices—for example, transcranial potential negative effects: the body’s magnetic stimulation, or TMS—to immune defence system may have an change the brain, at least temporarily. The big picture adverse reaction if it determines this These have the potential to affect Research is inherently interconnected foreign material should be eliminated. someone’s personality or identity. with many scientific fields and is How much is a person responsible for not performed in isolation from our Enhancing the brain their actions if their brain is artificially values and policies in society. While Developing treatments for brain altered? In this context, what is the researchers pursue their ideas to diseases and disorders is an important threshold of manipulation below advance science, they do it knowing goal in neuroscience. By definition, which a person’s brain would still be there are potential downsides along this involves enhancing a diseased considered normal? with the benefits. or disordered brain. The next step is how we might enhance normal Important ethical concerns in neuroscience brains. There are upsides to cognitive enhancement: boosting memory or • Treatments that may change • Consent from people who have a intelligence or creativity. But there personality or identity brain disease or disorder are clear downsides too: who will have access to this technology and • Unintended or unknown effects of • How prediction of brain disorders and altering DNA in the brain diseases may impact health insurance how should it be regulated? At what coverage point should cognitive enhancement • How much should we be able to stop? What unintended consequences enhance function? • Anticipating possible alternative use, and misuse, of neuroscience might there be? What kind of • Fair access to technology that technology enhancement crosses a line into unfair enhances brain function
CREDITS: GETTY, ISOCK GETTY, CREDITS: advantage or brain doping?
QBI.UQ.EDU.AU/NATURE-DISCOVERY The BRAIN series 23 Next steps
Investing in the future
he ultimate aim of most molecules are important for neuron passed from one neuron to another research is to improve the communication and repair. and how neurons form networks, but Thuman condition, from working Almost two decades later, our there is still much to be learnt about on treatments for diseases like body of fundamental research the molecular and cellular machinery Alzheimer’s, to improving crop yields is contributing to more than our underlying these processes—with and reaching for the stars. As we have knowledge of how the brain works—it potential impacts on improving explored in this magazine, discovery is also being translated into potential learning and memory, combating and fundamental science research has treatments for currently incurable neurodegenerative diseases, and the potential for significant impact nervous system disorders. QBI is stimulating recovery from brain injury. on our quality of life. It is with these progressing several clinical human The Queensland Brain Institute's foundations that UQ’s Queensland trials, including two clinical safety Discovery Research Endowment Fund Brain Institute was established in trials which are being planned: a trial has been established to embrace 2003, with the premise of focusing of a drug to slow MND progression, the critical role that philanthropic on fundamental discovery science based on 23 years of research by donations play in progressing new, and the aim of leading the world in the Institute's inaugural director, out-of-the-box ideas that lead to neuroscience research. Emeritus Professor Perry Bartlett, and scientific breakthroughs. Our long- The Institute now has a collection a non-invasive ultrasound treatment term hope for the fund, through of internationally respected to improve memory functions in philanthropic support, is to address researchers who routinely have their people living with dementia. unmet needs—supporting young work published in the top scientific Importantly, this clinical research researchers; backing early stage, journals. Our neuroscientists have would not have been possible high-risk, high-reward projects; and made important discoveries, without first understanding how providing seed funding to secure including that new neurons can be these diseases affect the brain government support for larger made in the adult brain, vitamin D at a molecular level, and indeed, initiatives. These niche areas are often plays a critical role in early brain how the neurons and molecules not catered for by government, yet development, and certain signalling involved operate normally. Many of can have an enormous impact on our laboratories are attempting to solving major health issues facing ... discovery and unravel what seem to be relatively society today, including dementia, fundamental science simple processes but are, in fact, depression, anxiety, and stroke. incredibly complex. For example, how Society’s investment in fundamental research has the potential do neurons communicate with each research is an investment in future for significant impacts on other? We have gathered extensive science that may solve some of our our quality of life. knowledge about how information is biggest health and ageing issues. CREDITS: QBI CREDITS:
24 The BRAIN series QUEENSLAND BRAIN INSTITUTE Owning the unknown at the Queensland Brain Institute Our scientists are unlocking the mysteries of the brain to understand and treat disease, improve learning and memory, and inspire technology. Help them discover more. qbi.uq.edu.au/discovery CREDITS: QBI CREDITS: w: qbi.uq.edu.au / e: [email protected] / p: +61 7 3346 6300