Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scents will not rouse us from slumber, says new Brown University study

18.05.2004


While sound can disrupt sleep, scents cannot. People cannot rely on their sense of smell to awaken them to the danger of fire, according to a new Brown University study.



Study participants easily detected odors when awake and in the early transition into sleep (Stage One sleep) but, once asleep, did not. The findings indicate a significant alteration of perceptual processing as a function of sleep.

“Human olfaction appears insufficiently sensitive and reliable to act as a sentinel system,” said Rachel S. Herz, visiting assistant professor of psychology and an author of a study titled “Minimal Olfactory Perception During Sleep: Why Odor Alarms Will Not Work for Humans,” published in a recent issue of the journal Sleep.


Researchers studied the effects of two scents – the pleasurable peppermint and offensive pyridine – on six participants in their early 20s.

Over two nights, participants wore an elastic chinstrap to encourage nose breathing. Researchers presented odors through a tube attached to an air-dilution device. The odors were tested during moderately deep Stage Two sleep, deep Stage Four sleep and REM (rapid eye movement) sleep.

No one responded to peppermint during sleep. Responses to the intense and noxious pyridine were infrequent and did not wake any participants in the deepest stage of sleep. Pyridine is a component of coal tar and used as a herbicide for firewood, and thus a likely byproduct of many real fires, according to the authors.

However, sound woke the participants regardless of the sleep stage. A moderately loud auditory tone produced arousal from sleep virtually every time the scents did not.

Most odors stimulate people’s trigeminal nerve to some degree, which is relevant to detection of the scent. Both odors used in the study were of comparable trigeminal strength even though one was pleasant and the other aversive at high concentrations.

“As the saying goes,” said the paper’s co-author Mary A. Carskadon, “we ‘wake up and smell the coffee,’ not the other way around.” Carksadon is a professor of psychiatry and human behavior in the Brown Medical School and director of chronobiology at E.P. Bradley Hospital.

The research was supported by a Grass Foundation Trustee Grant and approved by the Institutional Review Board of the E.P. Bradley Hospital.

Kristen Cole | Brown University
Further information:
http://www.brown.edu/Administration/News_Bureau/2003-04/03-139.html

More articles from Studies and Analyses:

nachricht Obstructing the ‘inner eye’
07.07.2017 | Friedrich-Schiller-Universität Jena

nachricht Drone vs. truck deliveries: Which create less carbon pollution?
31.05.2017 | University of Washington

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

Im Focus: Laser-cooled ions contribute to better understanding of friction

Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision

Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

NASA looks to solar eclipse to help understand Earth's energy system

21.07.2017 | Earth Sciences

Stanford researchers develop a new type of soft, growing robot

21.07.2017 | Power and Electrical Engineering

Vortex photons from electrons in circular motion

21.07.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>