Weekly Neuroscience Update

Neuron_cluster.width-800

TDP-43 inclusions are found in cells in the central nervous system. Image Credit: M. Oktar Guloglu, Wikimedia Commons

A team of researchers is fishing for a new method to treat neurodegenerative disorders. Its tactic? Bait dysfunctional proteins and prevent them from joining together into the kind of toxic globs found in almost every patient with ALS or frontotemporal dementia (FTD).

A ‘hit-and-run’ interaction between two proteins could be an important trigger for cell death, according to new research.

Biomedical engineers at Duke University have developed an automated process that can trace the shapes of active neurons as accurately as human researchers can, but in a fraction of the time.

Zapping the brains of people over 60 with a mild electrical current improved a form of memory enough that they performed like people in their 20s, a new study found.

Laughter really could be the best medicine when it comes to brain surgery. Neuroscientists at Emory University School of Medicine used electrical stimulation to activate a focal pathway in the brain and trigger laughter, which is immediately followed by a sense of calm and contentment. The technique was used while conducting diagnostic monitoring for seizure diagnosis on an epilepsy patient, with the effects later used to successfully undergo awake brain surgery on the same patient.

38 new genes have been implicated in hearing loss. One of the genes, SPNS2, has been linked to childhood deafness.

Increased kynurenic acid production has been implicated in the pathology of schizophrenia. The findings provide a new target for cell-specific treatments that help reduce the production of kynurenic acid and reduce symptoms of schizophrenia.

Scientists have pinpointed a group of cells in the brain whose activity could help explain the ability to share another’s pain.

Imbalanced communication between the hippocampus and amygdala may lead to the inability to distinguish between negative memories that have overlapping features. The findings could provide new treatment options for those with PTSD.

Finally this week, a new study reports that music synchronizes brainwaves across listeners with strong effects of repetition, familiarity and training.

Weekly Neuroscience Update

5ca4c9efcbd6e.jpg

How well-connected a particular brain network is, and how successfully memories are formed, may determine which patients with post-traumatic stress disorder benefit from behavioral therapy, researchers have found.

A new paper discusses the potential of deep brain stimulation in the treatment of Parkinson’s disease, OCD, Tourette syndrome and other disorders.

Reduced blood capillaries in the back of the eye may be a new, noninvasive way to diagnose early cognitive impairment, the precursor to Alzheimer’s disease in which individuals become forgetful, reports a newly published study.

Animal-assisted therapy can foster social competence in patients with brain injuries and increase their emotional involvement during therapy. 

CGRP, a protein associated with migraine pain, appears to act differently between sexes. Researchers say a female-specific mechanism of downstream CGRP receptor activation is likely to contribute to the higher prevalence of migraine in women.

A new model sheds light on the evolutionary origins of empathy and other associated phenomena. 

A team of scientists has shown that when deep-brain stimulation is applied to a specific brain region, it improves patients’ cognitive control over their behavior by increasing the power of a specific low-frequency brain rhythm in their prefrontal cortex.

Researchers have increased understanding of how computing technology could be used to help people with depression remember happy memories.

A study has found that childhood trauma is linked to abnormal connectivity in the brain in adults with major depressive disorder (MDD). The paper, published this week in Proceedings of the National Academy of Sciences (PNAS), is the first data-driven study to show symptom-specific, system-level changes in brain network connectivity in MDD.

Finally this week, the findings of an EEG study on two-month-old babies reveal the impact of maternal stress on early neurodevelopment.

Weekly Neuroscience Update

memory-fades-over-time-neurosciencneews

Much like opaque filters we apply to pictures on social media, the vibrancy of our memories dims and fades over time. The image reflects 12 levels of visual salience, or vibrancy, used to rate how memories fade. The image is credited to Psychological Science.

Low-level visual information fades in memory over time. However, negative emotion increases subjective memory vividness.

Musical training produces lasting improvements to a cognitive mechanism that helps individuals be more attentive and less likely to be distracted by irrelevant stimuli while performing demanding tasks.

Neurobiologists have studied the formation of inhibitory synapses, a complex process that occurs when the brain adapts. 

The synesthesia effect of being able to ‘hear’ silent movements may depend upon disinhibition of signaling between the visual and auditory brain regions. A new study found musicians are more likely to experience the ‘visual ear’ phenomena than those with no musical training.

Using OCT angiography to quantify capillary changes in the back of the eye can help in the detection, and monitor the progression, of Alzheimer’s disease.

Polygenetic risk scores calculated from adults can be used to identify children and adolescents who may be at greater risk of developing depression, even before clinical symptoms have emerged.

An uncommon variant of the PDE11A gene impacts both quality and duration of sleep. 

Scientists have discovered the key brain region for navigating well-known places, helping explain why brain damage seen in early stages of Alzheimer’s disease can cause such severe disorientation.

Finally this week, a team of researchers has found what they describe as a link between the “locus of control” in adolescents and their use of tobacco and alcohol.

Weekly Neuroscience Update

robot-eyes-motor-impairment-neurosciencneews.jpg

Robotic body surrogates can help people with profound motor deficits interact with the world. Here, Henry Evans, a California man who helped Georgia Tech researchers with improvements to a web-based interface, uses the robot to shave himself.  

People with profound motor deficits reported an improved quality of life while using robotic body surrogates.

A new study reports babies’ brains are sensitive to different emotional tones they hear in voices. Researchers suggest maternal interactions may help to shape the same brain region adults use for emotional processing.

Researchers are finding new evidence that exercise — even low-intensity, casual physical activity — can boost brain health in the short- and long-term.

The brain chemical serotonin, a neurotransmitter is long known for its role in passing signals between neurons in the brain, can also regulate expression of genes within neurons in an unexpected way, according to research conducted by neuroscientists at the Icahn School of Medicine at Mount Sinai and published on March 13 in the journal Nature.

New patterns of brain aging across the human lifespan have been revealed by scientists analysing microstructural changes in the brain’s white matter.

According to researchers, there is an optimum amount of dopamine that should be present within the brain. This optimum amount can help improve cognitive performance on tasks, researchers report.

Oxford University scientists have discovered a brain process common to sleep and aging in research that could pave the way for new treatments for insomnia.

Finally this week, a new review, which appears in The BMJ journal, examines the benefits of non-invasive brain stimulation for treating major depression and finds that the technique is a valid alternative to existing treatments.

How Experience Shapes Your Brain #BrainAwarenessWeek

Early experiences affect the development of brain architecture, which provides the foundation for all future learning, behaviour, and health.

Brains are built over time, from the bottom up.

The basic architecture of the brain is constructed through a process that begins early in life and continues into adulthood.

Simpler circuits come first and more complex brain circuits build on them later.

Brain architecture is comprised of billions of connections between individual neurons across different areas of the brain.

These connections enable lightning-fast communication among neurons that specialise in different kinds of brain functions. The early years are the most active period for establishing neural connections, but new connections can form throughout life and unused connections continue to be pruned.

The interactions of genes and experience shape the developing brain.

Genes provide the basic blueprint, but experiences influence how or whether genes are expressed. Together, they shape the quality of brain architecture and establish either a sturdy or a fragile foundation for all of the learning, health, and behaviour that follow.

Although genes provide the blueprint for the formation of brain circuits, these circuits are reinforced by repeated use.

A major ingredient in this developmental process is the interaction between children and their parents and other caregivers in the family or community.

In the absence of responsive caregiving—or if responses are unreliable or inappropriate—the brain’s architecture does not form as expected, which can lead to disparities in learning and behavior.

HCDC_Levitt-Plasticity-Curve_SHARE-768x540

It is easier and less costly to form strong brain circuits during the early years than it is to intervene or “fix” them later.

Cognitive, emotional, and social capacities are inextricably intertwined throughout the life course.

The brain is a highly integrated organ and its multiple functions operate in coordination with one another. Emotional well-being and social competence provide a strong foundation for emerging cognitive abilities, and together they are the bricks and mortar of brain architecture.


Adapted from The Center on the Developing Child at Harvard University

Center on the Developing Child at Harvard University

Weekly Neuroscience Update

20190304-brain-niaaa.jpg

NIH scientists present a new method for combining measures of brain activity (left) and glucose consumption (right) to study regional specialization and to better understand the effects of alcohol on the human brain.

Assessing the patterns of energy use and neuronal activity simultaneously in the human brain improves our understanding of how alcohol affects the brain, according to new research by scientists at the National Institutes of Health.

A new study reports teens with high levels of depression display poorer working memory in tests than those with low symptoms.

Eating a diet rich in fruits and vegetables, moderate in nuts, fish and alcohol and low in meat and full-fat dairy is associated with better cognitive performance in middle age, according to researchers.

A team of researchers has identified, for the first time, the cell types, areas and biological processes in the brain that mediate the genetic risk of insomnia.

Scientists report EEG technology has the ability to study activity of areas deep inside the brain, such as the thalamus and nucleus accumbens. The findings will help shed new light on disorders that affect these brain regions, such as Parkinson’s disease and OCD.

Researchers have identified a pathway near the midbrain where neural messages for taste and pain converge, a new study reports.

A new study reveals how blood vessels help protect the brain during inflammation. The findings could help in the development of new treatments for neurodegenerative and autoimmune diseases.

Choosing to forget something might take more mental effort than trying to remember it, scientists have discovered through neuroimaging.

According to researchers, keeping both physically and mentally active during middle age can significantly reduce the risk of developing dementia during old age. The study found women who participated in mental activities were 46% less likely to develop dementia, and those who were physically active at a 52% reduced risk.

Finally this week, a new study reveals women have higher activation in sensory areas of the brain associated with pain compared to males when witnessing another person suffering.

 

 

 

 

How Does Neurotransmission Work? #BrainAwarenessWeek

download - 2019-03-13T081122.475

How do brain cells communicate with one another to produce thoughts, feelings, and behavior?

They signal to one another using a process called neurotransmission.

But the transmission of these important chemical messages could not occur without unique cellular structures called receptors (a molecule in cells that serves as a docking station for another molecule).

Neurotransmission begins when one brain cell releases a neurochemical into the synapse (the space in between neurons.) But for a neighboring cell to “pick up” the message, that neurochemical must bind with one of its receptors.

When an electrical signal reaches the end of a neuron, it triggers the release of tiny sacs that had been inside the cells. Called vesicles, the sacs hold chemical messengers such as dopamine or serotonin.

860_main_neurotransmitterexplainer_0

This drawing shows a synapse — the space between two cells. The chemical messenger dopamine is inside the top cell. Receptors on the bottom cell are waiting to receive it.
NATIONAL INSTITUTE ON DRUG ABUSE

As it moves through a nerve cell, an electrical signal will stimulate these sacs. Then, the vesicles move to — and merge with — their cell’s outer membrane. From there, they spill their chemicals into the synapse.

Those freed neurotransmitters then float across the gap and over to a neighboring cell. That new cell has receptors pointing toward the synapse. These receptors contain pockets, where the neurotransmitter needs to fit.

It’s a bit like a game of catch. The first cell releases the neurochemical into the synapse and the receiving cell must catch it before it can read it and respond. The receptor is the
part of the cell that does the catching.

Signals for all of our sensations — including touch, sight and hearing — are relayed this way. So are the nerve signals that control movements, thoughts and emotions.

Each cell-to-cell relay in the brain takes less than a millionth of a second. And that relay will repeat for as far as a message needs to travel.

In recent years, researchers have learned that receptors are just as important as neurotransmitters in maintaining a healthy brain. In fact, studies have demonstrated that receptors play an important role in mood, learning, and social bonds. Receptors also mediate structural plasticity or remodeling of brain circuits that may result in changes to the number and type of synapses.

This short video discusses synaptic transmission in a simple and clear way.


 

Adapted from Dana Alliance for Brain Initiatives

As The World Wide Web Turns 30, How Is The Internet Changing Your Brain? #BrainAwarenessWeek

This day 30 years ago signaled the birth of the World Wide Web, ushering in the information age and revolutionizing life as we know it.

1_w2mB1iX1D6iOSihkS8nXzg.jpeg

Former physicist Tim Berners-Lee invented the World-Wide Web as an essential tool for High Energy Physics (HEP) at CERN from 1989 to 1994. Together with a small team he conceived HTML, http, URLs, and put up the first server and the first wysiwyg (what you see is what you get) browser and html editor. (Photo: CERN)

Vague but exciting.”

This was how Sir Tim Berners-Lee’s boss responded when the 33-year-old British physicist submitted his proposal for a decentralized system of information management on March 12, 1989.

Today there are over 4.4 billion internet users worldwide, growing at a rate of more than 11 new users per second. Internet user growth has accelerated in the past year, with more than 366 million new users coming online since January 2018.

This is your brain on the internet

The Internet takes advantage of the two most important features within the human brain – that social behaviour elicits pleasure and that vision triggers memories and emotions deep within our unconscious minds.

The first feature is that social activity triggers a nerve pathway deep in our subconscious – the mesolimbic dopamine pathway – also called the reward pathway, releasing a chemical called dopamine which bathes the brain’s pleasure centres – similar to other activities with intrinsic value such as food, sex and getting money.

Getting high on social activity

People like talking about themselves on social media because it has intrinsic value by generating a warm emotion of being part of something important. In other words, we like sharing because it is enjoyable for its own sake as a social activity. In this way sharing is deeply sensory – we humans literally ‘get high’ on social activity.

reward_pathway_jpeg

The image to the left is a view of the human brain cut down the middle. The reward pathway – shown in red – is activated by a rewarding stimulus.

The major structures in the reward pathway are highlighted: the ventral tegmental area (VTA), the nucleus accumbens and the prefrontal cortex.

The VTA sends information along its connections to both the nucleus accumbens and the prefrontal cortex. The neurons of the VTA contain the neurotransmitter dopamine which is released in the nucleus accumbens and in the prefrontal cortex. The pathway shown here is not the only pathway activated by rewards, other structures are involved too, but only this part of the pathway is shown for simplicity

The power of online images

The second feature worth noting is that over 70% of the human brain is dedicated to vision which means that our brains think in terms of visual images.

In fact, the visual system is the first to mature in the human brain so that by the age of five, children are able to compete on visual games with their grandparents …and win!

This explains why social networks like Instagram that use images are so popular.

The internet and the brain share common features

Ed Bullmore, professor of psychiatry at the University of Cambridge, has noted how the human brain and the internet have quite a lot in common.

“They are both highly non-random networks with a “small world” architecture, meaning that there is both dense clustering of connections between neighbouring nodes and enough long-range short cuts to facilitate communication between distant nodes, ” he points out.

Both the internet and the brain have a wiring diagram dominated by a relatively few, very highly connected nodes or hubs; and both can be subdivided into a number of functionally specialised families or modules of nodes. – Ed Bullmore

Berner Lee’s thoughts on the world wide web today

While the invention of the world wide web has changed our world in many positive ways, there is a dark side that has recently emerged.

In an open letter to mark the anniversary, Berner Lee questioned what it has become on the 30th anniversary of its creation, noting democracy and privacy were now under serious threat.

But he added it wasn’t too late to straighten the ship’s course.

“If we give up on building a better web now, then the web will not have failed us. We will have failed the web,” he wrote. “It’s our journey from digital adolescence to a more mature, responsible and inclusive future.”

We could equally apply these words to the neurobiology of internet usage. Whether the internet is changing our minds for the better or not is a debate that coalesced around Nicholas Carr’s book published a decade ago The Shallows: What the Internet Is Doing to Our Brains).  Carr argues that the internet is making us “more stupid” as we are losing the ability to concentrate and remember.

Perhaps the question is less about how the internet is changing our brains, but more accurately how is it changing our thinking.

But that’s a debate for another day.

Since we’re not going to dismantle the world wide web any time soon, the most important question is: how should we respond?

How Does Your Brain Work? #BrainAwarenessWeek

To mark Brain Awareness Week, a global campaign to increase public awareness of the progress and benefits of brain research, which runs from 11-17 March 2019, I will be posting a series of articles on the nature of the brain.

Your brain is a multilayered web of billions of nerve cells arranged in patterns that coordinate thought, emotion, behaviour, movement and sensation.

A complicated highway system of nerves connects your brain to the rest of your body so communication can occur in split seconds. Think about how fast you pull your hand back from a hot stove.

The outermost layer, the cerebral cortex (the “gray matter” of the brain), is a fraction of an inch thick but contains 70 percent of all neurons. Deep folds and wrinkles in the brain increase the surface area of the gray matter, so more information can be processed.

Your brain’s hemispheres are divided into four lobes.

bn00033-lobes-of-the-brain

  • The frontal lobes control thinking, planning, organizing, problem-solving, short-term memory and movement.
  • The parietal lobes interpret sensory information, such as taste, temperature and touch.
  • The occipital lobes process images from your eyes and link that information with images stored in memory.
  • The temporal lobes process information from your senses of smell, taste and sound. They also play a role in memory storage.

The cerebrum is divided into two halves (hemispheres) by a deep fissure. The hemispheres communicate with each other through a thick tract of nerves, called the corpus callosum, at the base of the fissure. In fact, messages to and from one side of the body are usually handled by the opposite side of the brain.

Slide1oo.jpg

Beneath the cortex are areas such as the basal ganglia, which controls movement; the limbic system, central to emotion; and the hippocampus, a keystone of memory.
The primitive brainstem regulates balance, coordination and life-sustaining processes such as breathing and heartbeat.

Throughout the brain, nerve cells (neurons) communicate with one another through interlocking circuits. Neurons have two main types of branches coming off their cell bodies. Dendrites receive incoming messages from other nerve cells. Axons carry outgoing signals from the cell body to other cells — such as a nearby neuron or muscle cell.

Complete_neuron_cell_diagram_en.svg

Interconnected with each other, neurons are able to provide efficient, lightning-fast communication. When a neuron is stimulated, it generates a tiny electrical current, which passes down a fiber, or axon. The end of the axon releases neurotransmitters —chemicals that cross a microscopic gap, or synapse — to stimulate other neurons nearby.

what-are-neurotransmitters-QBI.jpg

Neurotransmitters: Queensland Brain Inst.

Neurotransmitters pass through the synapse, the gap between two nerve cells, and attach to receptors on the receiving cell. This process repeats from neuron to neuron, as the impulse travels to its destination — a web of communication that allows you to move, think, feel and communicate.

While all the parts of your brain work together, each part is responsible for a specific function — controlling everything from your heart rate to your mood.


Sources

Dana Alliance for Brain Initiatives

Mayo Clinic