Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

People use handshakes to sniff each other out

03.03.2015

Limp or firm, your handshake conveys subliminal social cues. Now, research reveals it also transmits chemical signals that could explain why the greeting evolved in the first place.

In the study, published in the journal eLife, scientists from Israel's Weizmann Institute of Science found that people use the touch of a handshake to sample and sniff signalling molecules.


Scientists find that people use the touch of a handshake to sample and sniff signaling molecules. A sterile glove was used to identify signaling molecules transmitted via a handshake.

Credit: Frumin et al.

During the experiment, around 280 people were greeted either with or without a handshake. They were filmed using hidden cameras and observed to see how many times they touched their face. One finding of the study was that people constantly sniff their own hands -- keeping a hand at their nose about 22% of the time. Subjects greeted with a handshake significantly increased touching of their faces with their right hand. However, this only seemed to be the case when the subject had been greeted by a person of the same gender.

To check that the observed face-touching was being used as a way to subtly sniff the hand used in handshaking, subjects were fitted with nasal catheters to measure airflow. They found that when a hand was in close proximity to the nose airflow through the nasal passages doubled. In other words, the subject was sniffing.

""It is well-known that we emit odours that influence the behaviour and perception of others but, unlike other mammals, we don't sample those odours from each other overtly," says Professor Noam Sobel, Chair of Neurobiology at the Weizmann Institute of Science.

"Instead, our experiments reveal handshakes as a discreet way to actively search for social chemosignals," he said.

Previous studies have suggested that human chemosignals play a role in mate selection, conveying fear, altering brain activity, and synchronising women's menstrual cycles. To confirm that handshaking is effective at passing on this type of chemical, the scientists analysed the content of sterile gloves used to shake the hands of the subjects. They found that squalene and hexadecanoic acid, both chemicals thought to play a part in social signalling in dogs and rats, were transferred onto the gloves.

"Handshaking is already known to convey a range of information depending on the duration of the gesture, its strength and the posture used," says Professor Sobel. "We argue that it may have evolved to serve as one of a number of ways to sample social chemicals from each other, and that it still serves this purpose in a meaningful albeit subliminal way."

###

Reference

The paper 'A social chemosignalling function for human handshaking' can be freely accessed online at http://dx.doi.org/10.7554/eLife.05154. Contents, including text, figures, and data, are free to re-use under a CC BY 4.0 license.

An Insight article, 'Social chemosignaling: The scent of a handshake,' authored by Gün R. Semin & Ana Rita Farias of the Instituto Universitário, Lisbon, Portugal is available at http://dx.doi.org/10.7554/eLife.06758.

Media contact

Jennifer Mitchell, eLife
j.mitchell@elifesciences.org
+44 (0) 1223 855 373

About eLife Sciences Publications Ltd

eLife is a unique collaboration between the funders and practitioners of research to improve the way important research is selected, presented, and shared. eLife publishes outstanding works across the life sciences and biomedicine -- from basic biological research to applied, translational, and clinical studies. eLife is supported by the Howard Hughes Medical Institute, the Max Planck Society, and the Wellcome Trust. Learn more at elifesciences.org.

Jennifer Mitchell | EurekAlert!

Further reports about: airflow biological research nasal passages

More articles from Studies and Analyses:

nachricht Amputees can learn to control a robotic arm with their minds
28.11.2017 | University of Chicago Medical Center

nachricht The importance of biodiversity in forests could increase due to climate change
17.11.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

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: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>