idw – Informationsdienst Wissenschaft
Nachrichten, Termine, Experten
Nachrichten, Termine, Experten
A new study from the Humboldt-Universität zu Berlin has found how “ticklishness” is represented in the rat brain. The study has been published on 11th November 2016 in Science.
Of all physical sensations, ticklishness is perhaps the most mysterious. Why do we laugh in response to tickling? Why are certain body parts more ticklish? Why cannot we tickle ourselves? Indeed, the mystery of ticklish perception has been discussed for more than two millennia by great intellectuals including Aristotle and Charles Darwin. Despite such long-standing interest, the mechanism of ticklishness remained elusive.
The new study investigated tickling in rats. Earlier work had shown that young rats respond with 50 kHz ultrasonic “laughter-calls” to tickling by humans. In the novel study rats also reacted enthusiastically to the tickling: they emitted numerous calls. As judged by their calls, rats were most ticklish on the belly and underneath their feet. Rats often performed unsolicited joy jumps (Freudensprünge) after tickling, a behavior that can be seen in joyful subjects in various mammalian species. Rats also played with the researcher’s hand and chased it, and emitted similar calls during play.
The researchers (Shimpei Ishiyama & Michael Brecht) then went on to investigate the response of the rat’s brain to such tickling. Specifically, the investigators studied the rat’s somatosensory cortex, a large brain structure that contains an ordered representation of the body and handles stimuli on the body. In the trunk region of the somatosensory cortex, the researchers observed nerve cells that responded strongly to tickling. Interestingly, the researchers found very similar brain responses during play behaviours as during tickling, even though the rats were not touched by the scientist. Making rats anxious – which reduces ticklishness ¬– also reduced the activity in these cells and suppressed the calls. Remarkably, rats emitted calls just to electric stimulation of the cells in the trunk region of the somatosensory cortex without being tickled. Taken together, these results suggest that activity in the trunk somatosensory cortex represents ticklish sensation.
Professor Michael Brecht, who led the study, says: “The data much look like we identified the ticklish spot in the rat brain. I also find the similarity of brain responses to tickling and play remarkable. Perhaps ticklishness is a trick of the brain that rewards interacting and playing.”
S. Ishiyama & M. Brecht, Neural correlates of ticklishness in the rat somatosensory cortex. Science (2016). http://science.sciencemag.org/cgi/doi/10.1126/science.aah5114
More Informations
https://youtu.be/1ukqZj9xWyk
Kontakt
Prof. Dr. Michael Brecht
Humboldt-Universität zu Berlin
Tel: 030 2093-6770
michael.brecht@bccn-berlin.de
Shimpei Ishiyama HU
None
Merkmale dieser Pressemitteilung:
Journalisten, jedermann
Biologie, Psychologie
überregional
Forschungsergebnisse
Englisch
Shimpei Ishiyama HU
None
Sie können Suchbegriffe mit und, oder und / oder nicht verknüpfen, z. B. Philo nicht logie.
Verknüpfungen können Sie mit Klammern voneinander trennen, z. B. (Philo nicht logie) oder (Psycho und logie).
Zusammenhängende Worte werden als Wortgruppe gesucht, wenn Sie sie in Anführungsstriche setzen, z. B. „Bundesrepublik Deutschland“.
Die Erweiterte Suche können Sie auch nutzen, ohne Suchbegriffe einzugeben. Sie orientiert sich dann an den Kriterien, die Sie ausgewählt haben (z. B. nach dem Land oder dem Sachgebiet).
Haben Sie in einer Kategorie kein Kriterium ausgewählt, wird die gesamte Kategorie durchsucht (z.B. alle Sachgebiete oder alle Länder).
