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History of Brain Disease Research: 6 Incredible Advancements

History of Brain Disease Research

One research discovery has the potential to drive many more breakthroughs. Below we explore six groundbreaking discoveries that have changed the course of brain disease research and treatment.


At the American Brain Foundation, we support and fund research that works toward finding cures for all brain diseases. What’s most exciting is that a single breakthrough in brain disease research often has greater implications. This applies not just in unlocking new treatments, but also for opening up new understandings in other research areas.

This type of progress is what informs and upholds our philosophy of “Cure One, Cure Many.” To show the incredible impact of brain disease research, we’re sharing some of the most important historical advancements and discoveries about the brain—all made possible by research.

Fluid Biomarkers

Fluid biomarkers are chemical indicators in our blood, bodily fluids, or tissues. They can give doctors and researchers important information about how the body is functioning. They act as measurable signs of normal or abnormal biological processes. Additionally, they can indicate the presence of diseases, health risks, even the extent of a person’s responses to treatment.

Fluid biomarkers in cerebrospinal fluid (CSF) and blood plasma have become important for the early detection and diagnosis of neurodegenerative diseases like Alzheimer’s. Biomarkers help researchers measure changes in the brain and better understand various risk factors. They can also be helpful in selecting people who fit certain criteria for a clinical trial or research study.

Prior to the early 2000s, the only way to diagnose Alzheimer’s or other forms of dementia was through an autopsy. With advancements in research, doctors can now look for fluid biomarkers related to dementia while people are still alive. This development can improve diagnosis and treatment options. Four fluid biomarkers have been developed into tests to help support an Alzheimer’s diagnosis. While these are typically measured in CSF, new breakthroughs have made it possible to also use blood samples.

As researchers learn more about biomarkers, they can better track the onset and progression of neurodegenerative diseases. Consequently, they can measure the effectiveness of specific treatments. The hope is to make this type of testing and tracking more accessible in doctors’ offices and other clinical settings. Current biomarker research is working to improve early detection, diagnosis, and treatment of Alzheimer’s. It can also pave the way for new discoveries related to other types of dementia.

Brain Imaging and Mapping

Functional brain imaging and mapping technology has evolved over time thanks to new discoveries in cognitive neuroscience. Brain imaging helps scientists understand how our brain functions to support different mental activities. In addition, imaging technology can detect diseases like Parkinson’s and epilepsy. Current types of brain imaging technology include positron emission tomography (PET), functional magnetic resonance imaging (fMRI), electroencephalography (EEG), electrocorticography (ECoG), magnetoencephalography (MEG), and optical imaging with near-infrared spectroscopy (NIRS).

The invention of the EEG in 1929 revolutionized brain research by giving scientists the ability to measure electrical activity in the brain. Early brain imaging efforts also involved looking at brain blood flow and its connection to brain function and behavior. This research was motivated by the idea that when nerve cells in a certain part of the brain become active, there would be an increased blood supply to that area. Newer technology such as PET and MRI scans became available in the 1970s. Over time, they offered improved diagnostic capabilities and contributed to a deeper understanding of the brain.

First used in 1992, fMRI technology has presented another leap forward for researchers working to understand how complex mental processes are handled by different areas of the brain. Researchers are able to use fMRI to produce images showing what happens in the brain as people think and complete certain tasks. This has allowed us to map different functions to distinct parts of the brain. These more nuanced mapping capabilities have also opened up additional discoveries. For example, we now understand that different parts of the brain interact to complete different actions. We also recognize that certain networks within the brain become active for specific tasks. A deeper understanding of these interconnections will expand the possibilities for brain disease research.

Brain imaging technology is an area that continues to rapidly develop. Current research is exploring real-time 3D imaging as a way to further develop scientists’ understanding of how and where in the brain’s physical structure cognitive processes emerge. Researchers at Stanford are currently developing inexpensive technology for optical recordings of neurons, which could make brain mapping accessible on a larger scale and lead to a wave of new discoveries.

Neural Implants and Deep Brain Stimulation

Neural implants are devices that are surgically attached to the brain’s surface or cortex in order to stimulate, block, or monitor certain important signals between neurons. The implants emit constant electrical impulses that can stimulate certain brain functions. They can also cause neurons to communicate in a specific way. Their current use is treating various brain diseases, including therapies like deep brain stimulation and vagus nerve stimulation. In addition, they have uses in rehabilitation and communication with prosthetic limbs.

Deep brain stimulation (DBS) is a form of therapy in which electrodes are surgically placed in the brain to help manage the symptoms of a disease. The development of the neurostimulator was born from the success of the cardiac pacemaker. Adapting the pacemaker’s technology, neurosurgeons initially pursued neurostimulation as a way to treat chronic pain. But over time research uncovered a variety of other potential benefits to the technology.

In 2002, deep brain stimulation was approved by the Food and Drug Administration for treating Parkinson’s disease. That success prompted researchers to explore other uses. Since then, DBS received approval for the treatment of conditions like dystonia, epilepsy, and essential tremor. It is currently in clinical trials for the treatment of Tourette syndrome and psychiatric disorders like depression.

Researchers have also been exploring the therapeutic effects of neural implants on the vagus nerve. This nerve sends messages between important organs and the brain stem. Studies are underway to determine how vagus nerve stimulation could be used to treat stroke, epilepsy, migraine, and many other conditions. Brain imaging studies also offer promise for improving the performance of neural implants. This is because more complex understandings of how neurons communicate will allow doctors to adapt and expand neurostimulation treatments.

Genome Mapping

An incredible feat of scientific research, the Human Genome Project outlined our entire genetic blueprint. Between 1990 and 2003, an international team of researchers worked to sequence and map the DNA sequence of the human genome. Having a complete sequence of our genome gives researchers a clearer understanding of how our bodies function and evolve. Studies have been able to connect specific genes to an increased risk of developing certain diseases. Such connections offered a powerful tool for the early diagnosis of brain disease. For example, in 1997, the National Human Genome Research Institute discovered a genetic abnormality responsible for causing some cases of Parkinson’s disease.

The initial goal was to complete the sequence and create physical and genetic maps of the human genome. But scientists have since sequenced and mapped some animals as well. In recent years researchers have also expanded to more advanced drafts of mouse and rat genomes and variable bases of the human genome.

Now, scientists continue to study how different parts of the genome work together. They also look at how our genetic make-up relates to our health and common diseases. The hope is that genome-based research will help develop better diagnostic tools and treatments. Once it’s possible to perform detailed individualized analysis, healthcare professionals will be able to use specific insights to reduce an individual’s health risks and recommend more personalized health interventions.

Animal Models

Because we share many biological characteristics with certain animals, studying them can help us better understand some of our own cognitive processes, brain chemistry, and responsiveness to drug treatment. Animal models have become an important part of biomedical research—with the use of mouse models specifically growing since the 1990s. Along the way, scientists have discovered how to manipulate animal genomes to add (transgenic) or eliminate (knockout) specific genes.

In 1995, scientists created the first transgenic mouse model with a gene mutation for an inherited form of early-onset Alzheimer’s disease. This helped confirm and deepen researchers’ understandings of how specific beta-amyloid plaques may form and contribute to Alzheimer’s symptoms. Mouse models presented challenges in adequately modeling complex neurological diseases. So more research is necessary to understand how we might apply treatments that have been effective in mice to humans.

Despite those difficulties, animal models have contributed to discoveries in Alzheimer’s, Parkinson’s, and other neurodegenerative diseases. They have helped us gain a better understanding of how these diseases develop and progress. They also helped test the effectiveness of potential treatments and therapies.

As we move into the future, models will likely become more humanized to provide more accurate insights. In some cases, scientists may insert genetic material from humans into animal models so they more closely mimic human conditions. They may also create new models from different animal species. With the common goal of advancing our understanding of health and disease, researchers will look to explore how resources and knowledge can be applied across different animal models and related studies.

Discovery of Glial Cells

For many years scientists assumed the many brain cells that were not neurons were simply structural filler. These cells, called glia, are distinct from neurons, and over time their role has become clearer. Initially, it appeared that glial cells existed only to support neurons, but today research is exploring the more active role they play in brain communication and memory.

In the early 20th century, scientists discovered that people with certain brain conditions showed common, distinct patterns in glial cell formation and activity. They also found that even though glial cells don’t have axons—which means they don’t carry an electrical signal—their charge can change when exposed to a firing neuron. By the 1980s and 1990s, research sparked another breakthrough. Researchers found glial cells play an active role in sending and receiving signals to neurons and other glia.

Thanks to this progression of research discoveries, we know glial cells are involved in many important cognitive processes. They regulate brain communications, respond to injuries and infections, and support learning and memory.

For example, when specific types of glial cells overproduce a certain protein, it can result in the breakdown of synapses. This disrupts the connections between neurons and impairing memory retention. Glial cell research can impact our understanding of diseases marked by synapse loss. This will further our understanding of Alzheimer’s, amyotrophic lateral sclerosis, and multiple sclerosis.

As these six major research breakthroughs show, one discovery can lead to many more, with applications across multiple different forms of brain disease. Just as the parts of the brain are interconnected, different brain diseases may share common causes and potential treatments. When we learn more about one type of disease, it offers insight into others.

The American Brain Foundation believes that when we find the cure to one brain disease, we will find cures to many others. Learn more about the groundbreaking brain disease research we fund, or donate today to support the cures and treatments of tomorrow.