The findings settle a controversy in earlier studies that failed to establish the auditory region, called the planum temporale, as responsible for perception of auditory space by default.
The researchers, led by Dr. Leon Y. Deouell, of the Psychology Department and the Interdisciplinary Center for Neural Computation of the Hebrew University, and colleagues from the University of California, Berkeley, and the Weizmann Instititue of Science published their findings in the Sept. 20 issue of the journal Neuron, published by Cell Press. Working with Deouell on the project were Aaron S. Heller of University of California, Berkeley; Prof. Rafael Malach of the Weizmann Institute of Science; and Prof. Mark D’Esposito and Prof. Robert T. Knight of the University of California, Berkeley
Studies by other researchers had shown that the planum temporale was activated when people were asked to perform tasks in which they located sounds in space. However, many researchers believed that the region was responsible only for intentional processing of such information. And, in fact, previous studies had failed to establish that the planum temporale was responsible for automatic, nonintentional representation of spatial location.
Previous research done by Dr. Deouell and others has shown that some patients with brain damage may be specifically impaired in this function. Understanding how the normal brain machinery for this function is organized may help to understand why it breaks down and eventually how to mend it.
In their work, Deouell and colleagues used an improved experimental design that enabled them to more sensitively determine the brain’s auditory spatial location center. For example, they presented their human subjects with sounds against a background of silence, used headphones that more accurately reproduced sound location, and used noise with a rich spectrum, which has been shown to be more readily locatable in space. They also used sounds recorded from microphones placed in each subject’s own ears, and then played the same sounds back, thus tailoring the sounds specifically to the subjects’ own head and ears.
In their experiments, they presented bursts of the noise to the volunteers wearing the headphones while the subjects’ brains were scanned by functional magnetic resonance imaging. In this widely used brain-scanning technique, harmless magnetic fields and radio waves are used to image blood flow in brain regions, which reflects brain activity in those locations.
The subjects were instructed to ignore the sounds. And, to divert their attention, they either watched a movie with the sound turned off or were given a simple button-pushing task.
When the position of the noise bursts was varied in space, the researchers found that the planum temporale in the subjects’ brain was, indeed, activated. What’s more, the greater the number of distinct sound locations subjects heard during test runs, the greater the activity in the planum temporale.
The researchers thus concluded that their experiments “suggest that neurons in this region represent, in a nonintentional or preattentive fashion, the location of sound sources in the environment.”
Jerry Barach | The Hebrew University of Jerusal
Bergamotene - alluring and lethal for Manduca sexta
21.04.2017 | Max-Planck-Institut für chemische Ökologie
How to color a lizard: From biology to mathematics
13.04.2017 | Université de Genève
The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.
The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
29.05.2017 | Life Sciences
29.05.2017 | Physics and Astronomy
29.05.2017 | Statistics