Neuroscience

By Charles Choi, Inside Science -- Bloodcurdling screams in horror movies often send tingles down people's spines, even though they know such shrieks are fake. Now scientists have discovered the key ingredient of screams that activates the brain's fear circuitry. Inventors may have unknowingly copied this hair-raising acoustic feature into alarms found in cars and houses.

Are wind farms harmful to humans? Some believe so, others refute this; this controversial topic makes emotions run high. To give the debate more objectivity, an international team of experts dealt with the fundamentals of hearing in the lower limit range of the audible frequency range (i.e. infrasound), but also in the upper limit range (i.e. ultrasound). The project, which is part of the European Metrology Research Programme (EMRP), was coordinated by the Physikalisch-Technische Bundesanstalt (PTB). At PTB, not only acoustics experts, but also experts from the fields of biomagnetism (MEG) and functional magnetic resonance imaging (fMRI) were involved in the research activities.

Chronic pain caused by the nerve damage of type 2 diabetes, surgical amputation, chemotherapy and other conditions is especially intractable because it resists painkilling medications.

But in a study on mice, a Duke University team has shown that injections of stem cells from bone marrow might be able to relieve this type of neuropathic pain. The researchers say their findings, which appear July 13 in the Journal of Clinical Investigation, may also advance cell-based therapies in chronic pain conditions, lower back pain and spinal cord injuries.

The team used a type of stem cell known as bone marrow stromal cells (BMSCs), which are known to produce an array of healing factors and can be coaxed into forming most other types of cells in the body.

Researchers have uncovered further evidence of a system in the brain that persistently maintains memories for long periods of time.

Paradoxically, it works in the same way as mechanisms that cause mad cow disease, kuru, and other degenerative brain diseases. 

In four papers published in Neuron and Cell Reports, the laboratory of Eric Kandel at Columbia University Medical Center (CUMC) show how prion-like proteins - similar to the prions behind mad cow disease in cattle and Creutzfeld-Jakob disease in humans - are critical for maintaining long-term memories in mice, and probably in other mammals. 

Two migraine surgery techniques targeting a specific "trigger site" are both highly effective in reducing the frequency and severity of migraine headaches, according to a randomized trial.

Patients with temporal-type migraine derive similar and significant improvement from techniques that relieve pressure on (decompression) or remove a portion of (neurectomy) the nerve responsible for triggering their headaches, reports Bahman Guyuron, MD, Emeritus professor of plastic surgery at Case School of Medicine, Cleveland, and colleagues. 

The brains of people with recurrent depression have a significantly smaller hippocampus (the part of the brain most associated with forming new memories) than healthy individuals, according to a study of nearly 9,000 people called the ENIGMA study.

The researchers say this is the largest international study to compare brain volumes in people with and without major depression. It highlights the need to identify and treat depression effectively when it first occurs, particularly among teenagers and young adults. Using magnetic resonance imaged (MRI) brain scans, and clinical data from 1,728 people with major depression and 7,199 healthy individuals, the study combined 15 datasets from Europe, the USA and Australia. 

In a new study, researchers found that neurons in a specific brain region play a key role in rapidly forming memories about every day events, a finding that may result in a better understanding of memory loss and new methods to fight it in Alzheimer’s and other neurological diseases.

Specifically, the study examined neurons in the medial temporal lobe associated with episodic memory, the brain’s ability to consciously recall experienced events and situations like running into an old school friend at the opera. Episodic memory logs these unique experiences and relies on the very rapid formation of new associations in the brain.

Our brain recognizes objects within milliseconds, even if it only receives rudimentary visual information. Researchers believe that reliable and fast recognition works because the brain is constantly making predictions about objects in the field of view and is comparing these with incoming information.

Only if mismatches occur in this process do higher areas of the brain have to be notified of the error in order to make active corrections to the predictions. Now scientists at the Goethe University have confirmed this hypothesis. Those brain waves that are sent to higher brain areas increase their activity when a predictive error occurs. 

When rats rest, their brains simulate journeys to a desired future such as a tasty treat, finds new UCL research funded by the Wellcome Trust and Royal Society.

The researchers monitored brain activity in rats, first as the animals viewed food in a location they could not reach, then as they rested in a separate chamber, and finally as they were allowed to walk to the food. The activity of specialised brain cells involved in navigation suggested that during the rest the rats simulated walking to and from food that they had been unable to reach.

The study, published in the open access journal eLife, could help to explain why some people with damage to a part of the brain called the hippocampus are unable to imagine the future.

Sleep seems simple enough to define, it is a state of rest and restoration that almost every vertebrate creature must enter regularly in order to survive.

Yet the brain responds differently to stimuli when asleep than when awake, and it is not clear what brain changes happen during sleep.

A key question is why - it is the same brain, same neurons and similar requirements for oxygen so what is the difference between these two states?

In a recent paper, Rodolfo Llinás, a professor of neuroscience at New York University School of Medicine , and colleagues announced that a specific calcium channel plays a crucial role in healthy sleep, a key step toward understanding both normal and abnormal waking brain functions.