Tickling is among the least understood phenomenon in humans as well as animals. In order to better understand it, scientists have analyzed and tested various scenarios on rats. Apparently, they can also be tickled and researchers can see how the brain responds and so they started tickling rats for science.
In an attempt to answer the question of why laughter is the result of tickling and why some persons are more sensitive to it than others in certain areas of their bodies, scientists have developed a new study involving rats which was published Thursday in the journal Science.
Aristotle once thought that humans are the only ticklish animals, but researchers have discovered that rodents experience pleasure when they are being tickled on their bellies and backs and also experience a change of moods. Scientists then implemented electrodes in the rats’ brains to detect the activity of their brains while they are being tickled. They also had a microphone to record their squeaking.
By repeating the tickling in various conditions, scientists were able to pinpoint the ticklish point of the brain, specific neurons in the somatosensory cortex. The part of the brain which registers touch sensations. They also discovered that the rats who were in more stressful situations were not responding to tickling. For example, if exposed to bright lights and strange environments, the rats would not respond to being tickled, a sign that their sensitivity to tickling depends on their moods.
Michael Brecht and his colleagues from the Humboldt University of Berlin, Germany posit that they will see the same area of the brain light up when a person is being tickled, considering the similarity of structure of the brain between rats and people. They consider tickling to have an evolutionary role in social bonding and interaction.
Their research may have also discovered why we aren’t capable of tickling ourselves. They found that after repeating the tickling the rats a number of times, they would develop the expectation of the action. Their brain cells involved in tickling became active a few moments before they would actually be tickled. Brecht thinks that this anticipation only occurs in social interaction with other individuals.
What do you think about tickling rats for science?
Image credit:Shimpei Ishiyama and Michael Brecht / Humboldt University of Berlin/Science