A new study reveals for the first time that activating the brain's visual cortex with a small amount of electrical stimulation actually improves our sense of smell. The finding published in the Journal of Neuroscience by researchers at the Montreal Neurological Institute and Hospital - The Neuro, McGill University and the Monell Chemical Senses Center, Philadelphia, revises our understanding of the complex biology of the senses in the brain.
"It's known that there are separate specialized brain areas for the different senses such as vision, smell, touch and so forth but, when you experience the world around you, you get a coherent picture based on information from all the senses. We wanted to find out how this works in the brain," says Dr. Christopher Pack, lead investigator at The Neuro. "In particular we wanted to test the idea that activation of brain regions primarily dedicated to one sense might influence processing in other senses. What we found was that electrically stimulating the visual cortex improves performance on a task that requires participants to identify the odd odor out of a group of three." This result is interesting because it shows, for the first time, that on a basic level the brain structures involved in different senses are really quite interconnected in everyone - more so than previously understood.
"This 'cross-wiring' of senses has been described in people with synesthesia, a condition in which stimulation of one sense leads to automatic, involuntary experiences in a second sense, causing people to see the colour of numbers, or smell words, or hear odours for example, says Dr. Johan Lundstrom at Monell Chemical Senses Center. "Now this study shows that cross-wiring of the senses exists in all of us, so we could all be considered synesthetic to a degree."
To examine the possibility that activating the visual cortex influences the sense of smell, people were tested on smell tasks before and after application of TMS, a non-invasive method of stimulating targeted brain areas. TMS, or transcranial magnetic stimulation, was directed towards the visual cortex using a protocol that had been previously shown by researchers at The Neuro to improve visual perception. TMS is already widely used in the treatment of certain disease symptoms, and because TMS alters brain activity in a targeted area, it provides a powerful test of the hypothesis that visual cortex activation changes olfactory perception.
The results demonstrate that visual cortex activity is incorporated into the processing of smells, proving for the first time a cross-wiring of the visual and olfactory systems in the brain. Interestingly, the team did not find evidence for similar cross-wiring between olfactory and auditory systems. This suggests that vision may play a special role in binding together information from the different senses, a possibility that the researchers are currently exploring. In addition to Drs. Pack and Lundstrom, the research was carried out by Jahan Jadauji, a Master's student, and Jelena Djordjevic, a clinical neuropsychologist and neuroscientist, both at The Neuro. This collaboration between researchers and clinicians was made possible by The Neuro's integrated research institute and hospital.
This study was funded by a Centre of Excellence in Commercialization and Research grant, the Alfred P. Sloan Foundation, the Swedish Research Council, and the National Sciences and Engineering Research Council, as well as support from Mrs. Anna Engel.
The Montreal Neurological Institute and Hospital:
The Montreal Neurological Institute and Hospital — The Neuro, is a unique academic medical centre dedicated to neuroscience. Founded in 1934 by the renowned Dr. Wilder Penfield, The Neuro is recognized internationally for integrating research, compassionate patient care and advanced training, all key to advances in science and medicine. The Neuro is a research and teaching institute of McGill University and forms the basis for the Neuroscience Mission of the McGill University Health Centre. Neuro researchers are world leaders in cellular and molecular neuroscience, brain imaging, cognitive neuroscience and the study and treatment of epilepsy, multiple sclerosis and neuromuscular disorders. The Montreal Neurological Institute was named as one of the Seven Centres of Excellence in Budget 2007, which provided the MNI with $15 million in funding to support its research and commercialization activities related to neurological disease and neuroscience.
Anita Kar | EurekAlert!
New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)
Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology
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...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy