Neuroscience facts for kids

Neuroscience is the scientific study of the nervous system. This amazing system includes your brain, spinal cord, and all the nerves throughout your body. Scientists in this field want to understand how the nervous system works, what it does, and what happens when things go wrong.

It's a team effort! Neuroscience brings together many different sciences. These include studying the body's functions (physiology), its structure (anatomy), tiny molecules, how living things grow, cells, how we think (psychology), physics, computers, chemistry, medicine, and math. All these areas help us understand the basic parts of nerve cells (called neurons), support cells (called glia), and how they connect in neural circuits. Learning how our brains help us learn, remember, behave, see, and be aware is a huge challenge in science.

Over time, neuroscience has grown a lot. Scientists now use many different ways to study the nervous system. They look at tiny molecules and individual cells. They also use special tools to take pictures of the brain while people are thinking or moving.

Drawing by Santiago Ramón y Cajal (1899) of neurons in the pigeon cerebellum

History of Brain Science

Illustration from Gray's Anatomy (1918) of a lateral view of the human brain, featuring the hippocampus among other neuroanatomical features

The first studies of the nervous system go way back to ancient Egypt. People in the Neolithic period, long ago, even performed trepanation. This was a surgery where they drilled a hole in the skull. They did this to treat head injuries or certain brain conditions, or to relieve pressure. Ancient writings from around 1700 BC show that Egyptians knew some things about brain damage.

Early Egyptians thought the brain was just "cranial stuffing." When preparing bodies for mummification, they often removed the brain. They believed the heart was where intelligence came from. The historian Herodotus wrote that the first step of mummification was to remove the brain through the nostrils.

This idea that the heart was the center of thought changed with the Greek physician Hippocrates. He believed the brain was involved in sensing things. This made sense because our eyes, ears, and tongue are all near the brain. He also thought the brain was where our intelligence lived. Plato agreed that the brain held the thinking part of our soul. However, Aristotle still thought the heart was the center. He believed the brain just cooled the heat from the heart.

This view was common until the Roman physician Galen came along. He was a follower of Hippocrates and treated Roman gladiators. Galen noticed that his patients lost their ability to think when their brains were injured. This showed how important the brain was.

Many thinkers in the Medieval Muslim world also wrote about brain-related medical issues. These included Abulcasis, Averroes, Avicenna, Avenzoar, and Maimonides. Later, in Renaissance Europe, scientists like Vesalius, René Descartes, Thomas Willis, and Jan Swammerdam also made important discoveries about the nervous system.

The Golgi stain first allowed for the visualization of individual neurons.

In the late 1700s, Luigi Galvani showed that muscles and nerves could be excited by electricity. This was a big step! In 1843, Emil du Bois-Reymond proved that nerve signals were electrical. Hermann von Helmholtz then measured how fast these signals traveled. Later, in 1875, Richard Caton found electrical activity in the brains of rabbits and monkeys. Adolf Beck made similar findings in 1890.

Brain studies became much better after the microscope was invented. Also, Camillo Golgi developed a special staining method in the late 1890s. This method used a silver salt to show the amazing details of individual neurons. Santiago Ramón y Cajal used Golgi's technique. This led to the "neuron doctrine," which says that the neuron is the basic working unit of the brain. Golgi and Ramón y Cajal shared the Nobel Prize in Physiology or Medicine in 1906 for their work.

Around the same time, in 1815, Jean Pierre Flourens studied animals by carefully damaging small parts of their brains. He then watched how this affected their movement, senses, and behavior. Later, doctors like Marc Dax (1836) and Paul Broca (1865) worked with patients who had brain damage. They found that specific brain areas were responsible for certain functions, like language. These ideas supported Franz Joseph Gall's theory that different mental tasks happen in specific parts of the brain.

Brodmann's diagram of the cerebral cortex with the areas he identified

John Hughlings Jackson studied patients with epilepsy. He correctly figured out how the brain's motor control area was organized by watching how seizures spread through the body. Carl Wernicke also added to the idea that specific brain parts handle language understanding and speaking. In 1894, Edward Flatau published a brain atlas with photos of fresh brain sections. In 1897, Charles Scott Sherrington gave the name "synapse" to the connection between neurons.

In 1909, Korbinian Brodmann mapped 52 different areas of the cerebral cortex. These are known as Brodmann areas. Even today, modern brain imaging uses Brodmann's maps. They help show that different parts of the brain become active during specific tasks.

In the 20th century, neuroscience became its own important field of study. People like David Rioch, Francis O. Schmitt, and Stephen Kuffler helped make this happen. They brought together different sciences to study the brain. The first dedicated neuroscience department was started in 1964 at the University of California, Irvine.

3-D sensory and motor homunculus models at the Natural History Museum, London

While treating epilepsy, Wilder Penfield created maps of brain functions. He showed where different abilities like movement, sensation, memory, and vision were located. He published his findings in a book in 1950. Penfield and his team are known for creating the "cortical homunculus." This is a visual map of how different body parts are represented in the brain.

Our understanding of neurons became much more detailed in the 20th century. In 1952, Alan Lloyd Hodgkin and Andrew Huxley created a math model. It explained how electrical signals, called "action potentials," travel in neurons. In 1962, Bernard Katz described how signals pass across the tiny gaps between neurons, called synapses. Starting in 1966, Eric Kandel studied how learning and memory change neurons in a sea slug.

Many neuroscience organizations were formed in the 20th century. They provided places for scientists to share their work. Examples include the International Brain Research Organization (IBRO) and the Society for Neuroscience (SFN). Recently, neuroscience has also led to new fields like neuroeconomics (brain and money), neuroeducation (brain and learning), and neuroethics (brain and right/wrong).

Modern Neuroscience: Exploring the Brain

Human nervous system

The scientific study of the nervous system grew a lot in the last half of the 20th century. This was thanks to new tools in molecular biology, electrophysiology (studying electrical signals), and computational neuroscience (using computers to model the brain). These advances let scientists study the nervous system in every way. They look at how it's built, how it works, how it grows, what goes wrong, and how it can be fixed.

For example, we now understand a lot about what happens inside a single neuron. Neurons are special cells that communicate with each other. They send electrical or chemical signals across tiny connections called synapses. Many neurons have a long, thin part called an axon. Axons can reach far parts of the body and quickly carry electrical signals. These signals affect other neurons, muscles, or glands. A nervous system is made when many neurons connect in neural circuits and networks.

The nervous system in animals with backbones, like humans, has two main parts. These are the central nervous system (the brain and spinal cord) and the peripheral nervous system (all the other nerves). In many species, including humans, the nervous system is the most complex system in the body. Most of this complexity is in the brain. The human brain alone has about one hundred billion neurons and one hundred trillion synapses! It has thousands of different parts, all connected in complex ways. Scientists are still trying to understand all these connections. At least one out of three of our genes is mainly active in the brain.

The human brain is very flexible. The connections between its neurons can change throughout our lives. This helps us learn and adapt.

Understanding the brain's complex and changing nature is a huge research challenge. Scientists want to know everything about the nervous system. This includes how it works, how it develops, how it malfunctions, and how it can be changed or repaired. So, they study the nervous system at many levels. These range from tiny molecules and cells to whole systems and how we think. New technologies are always helping us make progress. Advances in electron microscopy, computer science, electronics, functional neuroimaging (brain scans), and genetics have all been very important.

New ways to classify brain cells have come from recording electrical signals. Also, single-cell genetic sequencing and high-quality microscopes have helped. These methods are sometimes combined into one process called patch-sequencing. This allows researchers to learn a lot about different cell types. For instance, they've found that human and mouse brains have similar basic cell types, but with some differences.

How the Brain Works: Different Levels of Study

Tiny Building Blocks: Molecular and Cellular Neuroscience

Photograph of a stained neuron in a chicken embryo

Molecular neuroscience asks how neurons use and respond to tiny molecular signals. It also looks at how axons form complex connections. Scientists use tools from molecular biology and genetics to understand how neurons grow. They also study how changes in genes affect brain functions. The shape, molecular makeup, and electrical properties of neurons are also important. Scientists want to know how these relate to different behaviors.

Cellular neuroscience explores how neurons process signals. These signals can be chemical or electrical. Scientists study how signals are handled by dendrites and somas. They also look at how neurotransmitters and electrical signals process information within a neuron. Dendrites are thin branches that receive signals from other neurons. Axons are long branches that send nerve impulses. Somas are the main cell bodies of neurons, holding the nucleus.

Another big part of cellular neuroscience is studying the development of the nervous system. Questions here include how the nervous system is organized into regions. Scientists also study how axons and dendrites grow. They look at how neurons and glia are created (neurogenesis and gliogenesis) and how neurons move to their correct places.

Computational neurogenetic modeling uses computer models to understand brain functions. It looks at how genes interact at the cellular level.

Brain Networks: Neural Circuits and Systems

Proposed organization of motor-semantic neural circuits for action language comprehension. Adapted from Shebani et al. (2013).

Systems neuroscience focuses on how the brain is built and how it works as it develops. It also studies how large networks of brain parts work together. Besides brain development, this field looks at how the brain processes sensory information. It studies how we use what we've learned to guide our behavior.

Questions in systems neuroscience include how neural circuits form and create functions. These functions include reflexes, combining different senses, motor coordination, daily body rhythms (circadian rhythms), emotional responses, learning, and memory. In short, this research studies how brain connections are made and changed. It also looks at how these connections affect our senses, movement, attention, decision-making, and emotions.

Scientists in this field are interested in how brain circuits affect learning new skills. They also study how specialized brain regions develop and change (neuroplasticity). Creating brain atlases, which are detailed maps of individual brains, is another important area.

Related fields like neuroethology and neuropsychology study how brain structures create specific animal and human behaviors. Neuroendocrinology looks at how the nervous system interacts with hormones. Psychoneuroimmunology studies how the nervous system interacts with the immune system. Even with many advances, we still don't fully understand how neuron networks perform complex thinking and behaviors.

Thinking and Behavior: Cognitive Neuroscience

Cognitive neuroscience asks how our thoughts and feelings are created by brain circuits. New powerful tools like neuroimaging (e.g., fMRI, PET, SPECT), EEG, MEG, electrophysiology, optogenetics, and human genetic analysis help scientists. These tools, combined with smart experiments from cognitive psychology, let researchers explore big questions. They can study how thinking and emotions are linked to specific brain parts.

While many studies look for the brain basis of thinking, recent research shows that brain findings and ideas work together. For example, neuroscience research on empathy has led to discussions in philosophy and psychology. Also, finding different memory systems in the brain has changed how we think about memory. It's not just a perfect copy of the past, but a creative and changing process.

Neuroscience also works with social and behavioral sciences. New fields like neuroeconomics, decision theory, social neuroscience, and neuromarketing study how the brain interacts with its environment. For example, one study used EEG to see how people's brains reacted to stories about energy efficiency.

Brain Models: Computational Neuroscience

Computational neuroscience explores many levels of brain study. These include how the brain develops, its structure, and how it performs thinking functions. Researchers in this field use mathematical models, theories, and computer simulations. They do this to describe and test realistic neurons and nervous systems. For example, biological neuron models are math descriptions of neurons that fire electrical signals. These models can describe how single neurons behave and how neural networks work. Computational neuroscience is often called theoretical neuroscience.

Neuroscience in Healthcare

Helping People: Clinical Neuroscience

Medical fields like neurology, psychiatry, neurosurgery, anesthesiology, neuropathology, and neuroradiology all deal with diseases of the nervous system. These fields diagnose and treat these conditions.

Neurology works with diseases of the central and peripheral nervous systems. Examples include amyotrophic lateral sclerosis (ALS) and stroke. Psychiatry focuses on problems with feelings, behavior, thinking, and perception. Anesthesiology deals with pain and changing consciousness using medicines. Neuropathology studies the changes in the nervous system and muscle diseases, often looking at cells under a microscope. Neurosurgery mainly uses surgery to treat nervous system diseases.

Neuroscience helps develop many neurotherapy methods. These treatments aim to help people with nervous system diseases.

Bridging Research and Care: Translational Neuroscience

An MRI of a human head showing benign familial macrocephaly (head circumference > 60 cm)

Recently, the lines between different medical specialties have become less clear. This is because all are influenced by basic neuroscience research. For example, brain imaging gives doctors clear biological information about brain conditions. This can lead to faster diagnosis, better predictions, and improved tracking of a patient's progress.

Integrative neuroscience tries to combine information from many research levels. The goal is to create a complete model of the nervous system. For instance, brain imaging combined with math models and theories can help us understand brain conditions.

Another important area is brain–computer interfaces (BCIs). These are machines that can communicate with and influence the brain. Scientists are researching them to repair neural systems and restore certain thinking abilities. BCI research uses special technology platforms. These platforms can record brain signals in high detail. They also process these signals in real-time and test them in hospitals and labs.

Main Areas of Neuroscience Study

Modern neuroscience education and research can be grouped into these main areas. They are based on what is being studied and the methods used. However, many neuroscientists work on questions that cover several of these fields.

Careers in Neuroscience: What Can You Do?

The types of jobs for neuroscience graduates depend on their education level.

Bachelor's Level

Master's Level

Advanced Degree

Neuroscience Organizations: Working Together

The largest professional neuroscience group is the Society for Neuroscience (SFN). It's based in the United States but has many members from other countries. Since it started in 1969, the SFN has grown a lot. In 2010, it had over 40,000 members from 83 countries. Its yearly meetings bring together researchers, students, and many companies that supply research products.

Other big neuroscience organizations include the International Brain Research Organization (IBRO) and the Federation of European Neuroscience Societies (FENS). FENS includes 32 national groups, like the British Neuroscience Association. Nu Rho Psi was the first national honor society for neuroscience, founded in 2006. There are also many youth neuroscience societies for college students and early career researchers.

In 2013, the BRAIN Initiative was announced in the US. The International Brain Initiative started in 2017. It now includes more than seven national brain research efforts from different continents.

Sharing Knowledge: Public Education

Neuroscientists also work to share knowledge about the nervous system with the public and government. They do this individually and through large organizations. For example, individual neuroscientists help organize the International Brain Bee. This is a science competition for high school students around the world. In the United States, the Society for Neuroscience created "Brain Facts." They also work with teachers to develop "Neuroscience Core Concepts" for K-12 students. They co-sponsor "Brain Awareness Week" with the Dana Foundation to increase public knowledge about brain research. In Canada, the Canadian National Brain Bee is held every year at McMaster University.

Neuroscience teachers formed a group called Faculty for Undergraduate Neuroscience (FUN) in 1992. They share best teaching practices and help college students present their research.

Neuroscientists also work with education experts to study and improve teaching methods. This new field is called educational neuroscience. Government agencies like the National Institute of Health (NIH) and National Science Foundation (NSF) in the US have funded research on the best ways to teach neuroscience.

Neuroscience in Technology: Engineering Applications

Neuromorphic Computer Chips

Neuromorphic engineering is a field that creates working physical models of neurons. These models are used for useful computing. The way neuromorphic computers calculate is different from regular computers. They are complex systems with many connected parts, not one central processor.

One example is the SpiNNaker supercomputer.

Sensors can also be made smart with neuromorphic technology. The Event Camera's BrainScaleS is an example. It's a brain-inspired supercomputer at Heidelberg University in Germany. It was developed as part of the Human Brain Project. BrainScaleS copies biological neurons and their connections physically. Its silicon components make these model neurons work much faster than real ones, about 864 times faster.

Recent advances in neuromorphic microchip technology have led scientists to create an artificial neuron. This artificial neuron can replace real neurons in certain diseases.

Nobel Prizes for Brain Discoveries

Year	Prize field	Image	Laureate	Lifetime	Country	Rationale
1904	Physiology		Ivan Petrovich Pavlov	1849–1936	Russian Empire	"in recognition of his work on the physiology of digestion, through which knowledge on vital aspects of the subject has been transformed and enlarged"
1906	Physiology		Camillo Golgi	1843–1926	Kingdom of Italy	"in recognition of their work on the structure of the nervous system"
			Santiago Ramón y Cajal	1852–1934	Restoration (Spain)
1911	Physiology		Allvar Gullstrand	1862– 1930	Sweden	"for his work on the dioptrics of the eye"
1914	Physiology		Robert Bárány	1876–1936	Austria-Hungary	"for his work on the physiology and pathology of the vestibular apparatus"
1932	Physiology		Charles Scott Sherrington	1857–1952	United Kingdom	"for their discoveries regarding the functions of neurons"
			Edgar Douglas Adrian	1889–1977	United Kingdom
1936	Physiology		Henry Hallett Dale	1875–1968	United Kingdom	"for their discoveries relating to chemical transmission of nerve impulses"
			Otto Loewi	1873–1961	Austria Germany
1938	Physiology		Corneille Jean François Heymans	1892–1968	Belgium	"for the discovery of the role played by the sinus and aortic mechanisms in the regulation of respiration"
1944	Physiology		Joseph Erlanger	1874–1965	United States	"for their discoveries relating to the highly differentiated functions of single nerve fibres"
			Herbert Spencer Gasser	1888–1963	United States
1949	Physiology		Walter Rudolf Hess	1881–1973	Switzerland	"for his discovery of the functional organization of the interbrain as a coordinator of the activities of the internal organs"
			António Caetano Egas Moniz	1874–1955	Portugal	"for his discovery of the therapeutic value of leucotomy in certain psychoses"
1955	Chemistry		Vincent du Vigneaud	1901–1978	United States	"for his work on biochemically important sulphur compounds, especially for the first synthesis of a polypeptide hormone" (Oxytocin)
1957	Physiology		Daniel Bovet	1907–1992	Italy	"for his discoveries relating to synthetic compounds that inhibit the action of certain body substances, and especially their action on the vascular system and the skeletal muscles"
1961	Physiology		Georg von Békésy	1899–1972	United States	"for his discoveries of the physical mechanism of stimulation within the cochlea"
1963	Physiology		John Carew Eccles	1903–1997	Australia	"for their discoveries concerning the ionic mechanisms involved in excitation and inhibition in the peripheral and central portions of the nerve cell membrane"
			Alan Lloyd Hodgkin	1914–1998	United Kingdom
			Andrew Fielding Huxley	1917–2012	United Kingdom
1967	Physiology		Ragnar Granit	1900–1991	Finland Sweden	"for their discoveries concerning the primary physiological and chemical visual processes in the eye"
			Haldan Keffer Hartline	1903–1983	United States
			George Wald	1906–1997	United States
1970	Physiology		Julius Axelrod	1912–2004	United States	"for their discoveries concerning the humoral transmittors in the nerve terminals and the mechanism for their storage, release and inactivation"
			Ulf von Euler	1905–1983	Sweden
			Bernard Katz	1911–2003	United Kingdom
1973	Physiology		Karl von Frisch	1886–1982	Austria	"for their discoveries concerning organization and elicitation of individual and social behaviour patterns"
			Konrad Lorenz	1903–1989	Austria
			Nikolaas Tinbergen	1907–1988	Netherlands
1977	Physiology		Roger Guillemin	1924–2024	France	"for their discoveries concerning the peptide hormone production of the brain"
			Andrew V. Schally	1926–2024	Poland
1981	Physiology		Roger W. Sperry	1913–1994	United States	"for his discoveries concerning the functional specialization of the cerebral hemispheres"
			David H. Hubel	1926–2013	Canada	"for their discoveries concerning information processing in the visual system"
			Torsten N. Wiesel	1924–	Sweden
1986	Physiology		Stanley Cohen	1922–2020	United States	"for their discoveries of growth factors"
			Rita Levi-Montalcini	1909–2012	Italy
1991	Physiology		Erwin Neher	1944–	Germany	"For their discoveries concerning the function of single ion channels in cells"
			Bert Sakmann	1942–	Germany
1997	Physiology		Stanley B. Prusiner	1942–	United States	"for his discovery of Prions - a new biological principle of infection"
1997	Chemistry		Jens C. Skou	1918–2018	Denmark	"for the first discovery of an ion-transporting enzyme, Na+, K+ -ATPase"
2000	Physiology		Arvid Carlsson	1923–2018	Sweden	"for their discoveries concerning signal transduction in the nervous system"
			Paul Greengard	1925–2019	United States
			Eric R. Kandel	1929–	United States
2003	Chemistry		Roderick MacKinnon	1956–	United States	"for discoveries concerning channels in cell membranes [...] for structural and mechanistic studies of ion channels"
2004	Physiology		Richard Axel	1946–	United States	"for their discoveries of odorant receptors and the organization of the olfactory system"
			Linda B. Buck	1947–	United States
2012	Chemistry		Robert Lefkowitz	1943–	United States	"for studies of G-protein-coupled receptors""
			Brian Kobilka	1955–	United States
2014	Physiology		John O'Keefe	1939–	United States United Kingdom	"for their discoveries of place and grid cells that constitute a positioning system in the brain"
			May-Britt Moser	1963–	Norway
			Edvard I. Moser	1962–	Norway
2017	Physiology		Jeffrey C. Hall	1939–	United States	"for their discoveries of molecular mechanisms controlling the circadian rhythm"
			Michael Rosbash	1944–	United States
			Michael W. Young	1949–	United States
2021	Physiology		David Julius	1955–	United States	"for their discoveries of receptors for temperature and touch"
			Ardem Patapoutian	1967–	Lebanon United States
2024	Physics		John Hopfield	1933–	United States	"for foundational discoveries and inventions that enable machine learning with artificial neural networks"
			Geoffrey Hinton	1947–	United Kingdom

See also

In Spanish: Neurociencia para niños