People are adept at recognizing sensations such as sounds or smells, even when many stimuli appear simultaneously. But how the association works between the current event and memory is still poorly understood. Scientists at the Bernstein Center and the Ludwig-Maximilians UniversitÃ t (LMU) MÃ nchen have developed a mathematical model that accurately mimics this process with little computational effort and may explain experimental findings that have so far remained unclear. ( PLoS ONE, September 14, 2011) The so-called 'cocktail party-problem' has already kept scientists busy for decades. How is it possible for the brain to filter familiar voices out of background noise? It is a long-standing hypothesis that we create a kind of sound library in the auditory cortex of the brain during the course of our lives.
Precise diagnosis of disease and developmental syndromes often depends on understanding the genetics underlying them. Most cases of early onset hearing loss are genetic in origin but there are many different forms. Heretofore, it has been difficult to identify the gene responsible for the hearing loss of each affected child, because the critical mutations differ among countries and populations. New research published in BioMed Central's open access journal Genome Biology has identified six critical mutations in Israeli Jewish and Palestinian Arab families. Mutations in one gene, TMC1, was found in 38% of children with genetic hearing loss in the Moroccan Jewish population. Using targeted DNA capture and massively parallel sequencing (MPS), researchers screened 246 deafness-related genes in 11 unrelated individuals, all of whom were diagnosed with deafness that ran in their families.
Neuroscientists at the University of California, Berkeley, are offering hope to the 10 percent of the population who suffer from tinnitus - a constant, often high-pitched ringing or buzzing in the ears that can be annoying and even maddening, and has no cure. Their new findings, published online last week in the journal Proceedings of the National Academy of Sciences, suggest several new approaches to treatment, including retraining the brain, and new avenues for developing drugs to suppress the ringing. "This work is the most clearheaded documentation to this point of what's actually happening in the brain's cortex in ways that account for the ongoing genesis of sound, " said Michael Merzenich, professor emeritus of otolaryngology at UC San Francisco and inventor of the cochlear implant, who was not involved with the research.
A study led by Canadian researchers has found the first evidence that lifelong musicians experience less age-related hearing problems than non-musicians. While hearing studies have already shown that trained musicians have highly developed auditory abilities compared to non-musicians, this is the first study to examine hearing abilities in musicians and non-musicians across the age spectrum - from 18 to 91 years of age. The study was led by Baycrest's Rotman Research Institute in Toronto and is published online in the journal Psychology and Aging, ahead of print publication. Investigators wanted to determine if lifelong musicianship protects against normal hearing decline in later years, specifically for central auditory processing associated with understanding speech. Hearing problems are prevalent in the elderly, who often report having difficulty understanding speech in the presence of background noise.
Researchers at the Johns Hopkins University School of Medicine have found a protein normally involved in blood pressure regulation in a surprising place: tucked within the little "power plants" of cells, the mitochondria. The quantity of this protein appears to decrease with age, but treating older mice with the blood pressure medication losartan can increase protein numbers to youthful levels, decreasing both blood pressure and cellular energy usage. The researchers say these findings, published online during the week of August 15, 2011, in the Proceedings of the National Academy of Sciences, may lead to new treatments for mitochondrial-specific, age-related diseases, such as diabetes, hearing loss, frailty and Parkinson's disease. "We've identified a functional and independently operated system that appears to influence energy regulation within the mitochondria, " explains Jeremy Walston, M.