Neuroscience

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.

Males and females process pain using different cells, a new study with mice suggests.
The findings could help researchers develop the next generation of medications for chronic pain—the most prevalent health condition humans face.

“Research has demonstrated that men and women have different sensitivity to pain and that more women suffer from chronic pain than men, but the assumption has always been that the wiring of how pain is processed is the same in both sexes,” says co-senior author Jeffrey Mogil, professor of pain studies at McGill University and director of the Alan Edwards Centre for Research on Pain.

Researchers have found physical differences in the brains of people who respond emotionally to others' feelings, compared to those who respond more rationally.

The work led by Robert Eres from the Monash University School of Psychological Sciences, pinpointed correlations between grey matter density and cognitive and affective empathy. The study looked at whether people who have more brain cells in certain areas of the brain are better at different types of empathy.

Diabetes is a known risk factor for cognitive decline and dementia, age-related conditions that affect memory and thinking skills.

Cognitive behavioral therapy (CBT) can change the brain function of people with Tourette syndrome, said researchers at the Institut universitaire en santé mentale de Montréal and the University of Montreal at the First World Congress on Tourette Syndrome and Tic Disorders in London.

By Michael Greshko, Inside Science - Quantum mechanics governs the quirky, counterintuitive way the world works at the small scales of atoms and subatomic particles.