Posts tagged brain
Articles and news from the latest research reports.
Making Memories: Drexel Researchers Explore the Anatomy of Recollection
What was your high school mascot? Where did you put your keys last night? Who was the first president of the United States?
Groups of neurons in your brain are currently sending electromagnetic rhythms through established pathways in order for you to recall the answers to each of these questions. Researchers in Drexel’s School of Biomedical Engineering, Science and Health Systems are now getting a rare look inside the brain to discover the exact pattern of activity that produces a memory.
Dr. Joshua Jacobs, a professor in Drexel’s School of Biomedical Engineering, Science and Health Systems, is analyzing data accumulated from 60 epilepsy patients who have had electrodes implanted on their brains in order to determine the causes of their epileptic episodes.
"When performing seizure mapping, surgeons implant electrodes in many brain areas, while searching for seizure activity,” Jacobs said. “Thus, there many electrodes end up being in normal brain tissue, and they measure neuronal activity that reflects normal brain function – this is the function that we’re studying to learn about the nature of working memory."
![Hallucinations with Oliver Sacks, November 9, 8 P.M. EST [Live]
The renown neurologist talks about how the brain creates hallucinations — watch this hour-long discussion live and send questions to him via Twitter (using the hashtag #AskOliver to @WorldSciFest).
The conversation, at Cooper Union in New York City, will canvass the rich cultural history and contemporary science of the hallucinatory experience and will also touch on Sacks’ own early psychedelic forays that helped convince him to dedicate his life to neurology and to write about the myriad riddles of the human mind.
Can’t wait? Listen to the Nature podcast interview with Sacks by Kerri Smith, Nature’s podcast editor. Sacks recounts some interesting drug-induced trips, including one in which he has a philosophical discussion with a spider.](http://40.media.tumblr.com/tumblr_md8lgm6Gsm1rog5d1o1_500.jpg)
Hallucinations with Oliver Sacks, November 9, 8 P.M. EST [Live]
The renown neurologist talks about how the brain creates hallucinations — watch this hour-long discussion live and send questions to him via Twitter (using the hashtag #AskOliver to @WorldSciFest).
The conversation, at Cooper Union in New York City, will canvass the rich cultural history and contemporary science of the hallucinatory experience and will also touch on Sacks’ own early psychedelic forays that helped convince him to dedicate his life to neurology and to write about the myriad riddles of the human mind.
Can’t wait? Listen to the Nature podcast interview with Sacks by Kerri Smith, Nature’s podcast editor. Sacks recounts some interesting drug-induced trips, including one in which he has a philosophical discussion with a spider.
(Source: scientificamerican.com)
Flipping on the Lights to Halt Seizures
Targeted light transmission to genetically altered brain cells stops seizures cold.
Strobe lights can trigger epileptic seizures. Now imagine a light that stops a seizure a split second after it starts.
By applying pulses of light to genetically altered nerve cells deep in rat brains, researchers at Stanford and Pierre and Marie Curie University in France have done just that. Their results, which showed for the first time how a part of the brain called the thalamus is involved with epileptic seizures, were published in Nature Neuroscience.
The study could point toward new targets for epilepsy treatment, says Ed Boyden, associate professor and leader of the Synthetic Biology Group at MIT. Boyden was not involved in the work. Some ideas “might emerge immediately from knowing new targets to insert deep brain stimulation electrodes,” a type of device already used to help people with epilepsy, Boyden says.
The latest research looked at a kind of seizure that sometimes follows damage to the cerebral cortex, the outer part of the brain, from strokes or head injuries. Previous reports had hinted that the cortex might also communicate during a seizure with the thalamus, the brain’s message relay center.
In the current study, experiments with rats confirmed that the thalamus propagates seizure activity originating in the cortex. To see if the thalamus could be a target for treating seizures, Jeanne Paz, the paper’s lead author, and her colleagues turned to optogenetics, a technology that lets researchers use light to turn brain cells on and off.
For the “genetics” part, they used a virus to insert the DNA code for a light-sensitive protein into thalamus cells of rats. When exposed to light, the protein interferes with these cells’ ability to communicate.
The researchers then developed a light source that would turn on only when a rat had a seizure. To detect seizures, they implanted electrodes into the rats’ brains. When these electrodes registered a seizure starting, light from a laser was aimed directly at the genetically altered thalamus cells. The result, the researchers found, was that flipping on the light immediately stopped the seizure activity, proving that the thalamus is needed to keep seizures going.
“We’re excited that just a brief light exposure was enough to stop the seizure,” says John Huguenard, Stanford professor of neurology and neurological sciences and an author of the study.
However, Huguenard says, an optogenetics-based brain implant to control seizures is a long way off because of the unknown risks of altering a person’s DNA with a virus. “I would want to be cautious,” he says.
(Source: technologyreview.com)
Measuring Metabolism Can Predict the Progress of Alzheimer’s with 90% Accuracy
When it comes to Alzheimer’s disease, scientists usually — and understandably — look to the brain as their first center of attention. Now researchers at Tel Aviv University say that early clues regarding the progression of the disease can be found in the brain’s metabolism.
In very early stages of the disease, before any symptoms appear, metabolic processes are already beginning to change in the brain, says PhD candidate Shiri Stempler of TAU’s Sackler Faculty of Medicine. Working with Profs. Eytan Ruppin and Lior Wolf of TAU’s Blavatnik School of Computer Science, Stempler has developed predictor models that use metabolic information to pinpoint the progression of Alzheimer’s. These models were 90 percent accurate in predicting the stage of the disease.
Published in the journal Neurobiology of Aging, the research is the first step towards identifying biomarkers that may ensure better detection and analysis of the disease at an early stage, all with a simple blood test. It could also lead to novel therapies. “We hope that by studying metabolism, and the alterations to metabolism that occur in the very early stages of the disease, we can find new therapeutic strategies,” adds Stempler.
Musical Training as a Framework for Brain Plasticity: Behavior, Function, and Structure
Musical training has emerged as a useful framework for the investigation of training-related plasticity in the human brain. Learning to play an instrument is a highly complex task that involves the interaction of several modalities and higher-order cognitive functions and that results in behavioral, structural, and functional changes on time scales ranging from days to years. While early work focused on comparison of musical experts and novices, more recently an increasing number of controlled training studies provide clear experimental evidence for training effects. Here, we review research investigating brain plasticity induced by musical training, highlight common patterns and possible underlying mechanisms of such plasticity, and integrate these studies with findings and models for mechanisms of plasticity in other domains.
How connections in the brain must change to form memories could help to develop artificial cognitive computers
Exactly how memories are stored and accessed in the brain is unclear. Neuroscientists, however, do know that a primitive structure buried in the center of the brain, called the hippocampus, is a pivotal region of memory formation. Here, changes in the strengths of connections between neurons, which are called synapses, are the basis for memory formation. Networks of neurons linking up in the hippocampus are likely to encode specific memories.
Grid cell firing patterns signal environmental novelty by expansion
The hippocampal formation plays key roles in representing an animal’s location and in detecting environmental novelty to create or update those representations. However, the mechanisms behind this latter function are unclear. Here, we show that environmental novelty causes the spatial firing patterns of grid cells to expand in scale and reduce in regularity, reverting to their familiar scale as the environment becomes familiar. Simultaneously recorded place cell firing fields remapped and showed a smaller, temporary expansion. Grid expansion provides a potential mechanism for novelty signaling and may enhance the formation of new hippocampal representations, whereas the subsequent slow reduction in scale provides a potential familiarity signal.
Young brain develops activity peaks while it is still growing
After a short period of growth, cultured networks of neurons regularly exhibit major activity in the absence of external stimulation. These “bursts” are entirely related to growth. At this stage, they have little to do with learning behaviour, as the network is still too young to sustain a process of memory formation. This has now for the first time been simulated for networks ranging in size from 10,000 to 50,000 neurons. The simulations provide insight into the role of the growth process in initial activity. Researchers at the University of Twente’s MIRA Institute recently published details of this work in PLOS ONE.
Brain study provides new insight into why haste makes waste
Why do our brains make more mistakes when we act quickly?
A new study demonstrates how the brain follows Ben Franklin’s famous dictum, “Take time for all things: great haste makes great waste.”
The research – conducted by Research Assistant Professor Richard Heitz and Jeffrey Schall, Ingram Professor of Neuroscience, at Vanderbilt University – has found that the brain actually switches into a special mode when pushed to make rapid decisions.
The study was published Nov. 7 in the journal Neuron.
How your brain likes to be treated at revision time
If you’re a student, you rely on one brain function above all others: memory.
These days, we understand more about the structure of memory than we ever have before, so we can find the best techniques for training your brain to hang on to as much information as possible. The process depends on the brain’s neuroplasticity, its ability to reorganise itself throughout your life by breaking and forming new connections between its billions of cells.
How does it work? Information is transmitted by brain cells called neurons. When you learn something new, a group of neurons activate in a part of the brain called the hippocampus. It’s like a pattern of light bulbs turning on.
Your hippocampus is forced to store many new patterns every day. This increases hugely when you are revising. Provided with the right trigger, the hippocampus should be able to retrieve any pattern. But if it keeps getting new information, the overworked brain might go wrong. That’s what happens when you think you’ve committed a new fact to memory, only to find 15 minutes later that it’s disappeared again.
So what’s the best way to revise? Here are seven top tips to get information into your brain and keep it there.