Weekly Neuroscience Update

this way, that wayWellcome Trust researchers have discovered how the brain assesses confidence in its decisions. The findings explain why some people have better insight into their choices than others.

Meanwhile, a study conducted by researchers at the University of Granada Group of Neuropsychology and Clinical Psychoneuroimmunology has demonstrated that cortisol levels in saliva are associated with a person’s ability to make good decisions in stressful situations.

Your brain has at least four different senses of location – and perhaps as many as 10. And each is different, according to new research from the Kavli Institute for Systems Neuroscience.

A month of daily transcranial magnetic stimulation targeting the supplemental motor area (SMA) results in lasting improvements in symptoms of Tourette syndrome, show study findings.

Researchers have used brain imaging technology to show that young people with a known genetic risk of bipolar but no clinical signs of the condition have clear and quantifiable differences in brain activity when compared to controls.

Researchers have found the first proof that a chemical in the brain called glutamate is linked to suicidal behavior, offering new hope for efforts to prevent people from taking their own lives.

Neurobiologists at the Research Institute of Molecular Pathology (IMP) in Vienna investigated how the brain is able to group external stimuli into stable categories. They found the answer in the discrete dynamics of neuronal circuits. The journal Neuron publishes the results in its current issue.

Photo Credit: photo credit: Lori Greig via photopin cc

Slow protein clearance ‘clue to Alzheimer’s’

Amyloid plaques build up in the brains of people with Alzheimer's disease. Image: BBC Health

The BBC News website this week reports on the latest research to suggest that people with Alzheimer’s disease clear a damaging protein from their brains more slowly than those who are healthy. With an ageing population,  dementia, including Alzheimer’s, is currently seen as one of the main health challenges in Ireland the UK.

Amyloid plaques are one of the hallmarks of Alzheimer’s disease. Amyloid is a general term for protein fragments that the body produces normally. Beta amyloid is a protein fragment snipped from an amyloid precursor protein. In a healthy brain, these protein fragments are broken down and eliminated. For some reason, in Alzheimer’s disease, the fragments accumulate to form hard, insoluble plaques.

The findings from this study suggests that people with Alzheimer’s disease clear the damaging protein from their brains 30% more slowly than those who are healthy suggesting that  it is the poor clearance of the protein, not the build-up, that is the problem. Admittedly it’s a small study – just 24 people were looked at, but exciting, and could help the understanding of the disease.

Not meaning to blow my own trumpet (ahem!) but in 2008 my research group showed how the amyloid protein might be toxic in higher concentration …by inappropriately increasing the concentrations of a neurotransmitter called glutamate in the hippocampus – a brain region long associated with Alzheimer’s disease*. It’s well known that high concentrations of glutamate can damage local nerve cells and thus impair the functioning of the hippocampus.

It’s exciting to see the pieces of evidence coming together as the search for an effective treatment for dementia continues apace.

*  O’Shea S.D., Smith I.M., McCabe O.M., Cronin M.M., Walsh D.M., O’Connor W.T. Sensors. 2008; 8(11):7428-7437.