neurology

In marathon runners, the myelin content of specific regions of the brain is reversibly reduced, according to a study carried out in the Basque Country. This observation is consistent with animal evidence suggesting that myelin lipids - a substance that surrounds neurons - can act as energy reserves in extreme metabolic conditions, as detailed by the authors in Nature Metabolism. The analysis is based on magnetic resonance imaging of eight men and two women before and after running a marathon. According to the study, the myelin content was fully recovered two months after the race.

An article reviews evidence on the accumulation of microplastics in human brain tissue recently published in Nature Medicine. The authors highlight practical measures to reduce exposure, noting that switching from bottled water to filtered tap water could reduce microplastic intake from 90,000 to 4,000 particles per year. The paper is a commentary in Brain Medicine. 

Results from a cohort study of more than 100,000 people reveal the strong and persistent association of headache diagnoses with attempted and completed suicide. The authors suggest that behavioural health assessment and treatment may be important for these patients. The paper is published today in the journal JAMA Neurology. 

A study in mice reveals that immune cells in the brain 'engulf' microplastics, forming clumps that can cause brain clots. The findings, published in the journal Science Advances, highlight how microplastics can indirectly damage the brain by disrupting blood flow, rather than directly infiltrating brain tissue cells. 

Until now, memories have been explained by the activity of neurons that respond to learning events and control recall. A study published in Nature changes this theory by showing that non-neuronal cells in the brain called astrocytes - star-shaped cells - also store memories and work in concert with clusters of connected neurons called engrams to regulate the storage and retrieval of memories.

Chronic pain is a public health problem that affects almost one in six people in Spain, with very different origins and characteristics. Specialists in psychology and pain explain what it is, how it is treated, what consequences it has for those who suffer from it and how to learn to live with it.

An international team of researchers has conducted a meta-analysis of 137 clinical trials involving nearly 90,000 people to assess the migraine efficacy of 17 available drugs. Their conclusions are that four drugs in the triptan group are more effective and cheaper than newer drugs such as gepants or lasmiditan, and that the efficacy of the latter is comparable to that of paracetamol and most anti-inflammatory drugs. The results are published in The BMJ.

Brain maturation is measured by the thickness of the cortex. It is known that stress accelerates cortical thinning, which is associated with a higher risk of developing neuropsychiatric disorders. A study published in PNAS analyzes MRI data collected from 160 adolescents before COVID-19 and from 130 of them after the measures implemented during the pandemic. The comparison of brain structure before and after reveals accelerated cortical thinning which, measured in terms of equivalent years of brain development, was 4.2 years in girls and 1.4 years in boys.brain maturity

Vision loss and having high cholesterol - the so-called ‘bad’ cholesterol - are risk factors for developing dementia, according to a meta-analysis published in The Lancet. Eliminating these risk factors could reduce dementia cases by 2% and 7% respectively, the study says. Both factors are in addition to 12 others previously mentioned in a 2020 report such as less education, physical inactivity, hearing loss, excessive alcohol consumption, obesity or poor social contact, among others. According to the research, almost half of all dementia cases could be prevented or delayed if these risk factors were controlled.

The European Medicines Agency (EMA) has recommended not granting marketing authorization for Leqembi™ (lecanemab) for the treatment of Alzheimer's disease. The EMA's Committee for Medicinal Products for Human Use (CHMP) considers that its effect in delaying cognitive decline does not outweigh the risk of serious side effects associated with the drug, in particular swelling and possible bleeding in patients' brains. Leqembi™ was approved in 2023 in the United States.