Structural, Neural and Mental Underpinnings of Rat Ticklishness

The primary objective of this proposal is to determine the structural, neural, and mental underpinnings of rat ticklishness. Tickling, a peculiar and amusing form of social touch, has been discussed by philosophers and scientists for more than two millennia. Despite a historical interest in tickling as a topic, fundamental questions remain unanswered: Why does tickling induce laughter? Why do body parts differ in ticklishness? Why can’t we tickle ourselves? Our previous work suggests that activity in layer 5 of trunk somatosensory cortex might be sufficient for evoking ticklishness in rats. We will build on these findings with three main goals in mind. (i) We will further corroborate that layer 5 of trunk somatosensory cortex harbours the neural substrate of ticklishness using pharmacological and optogenetic blocking techniques. (ii) We will identify the microcircuits mediating ticklishness and attempt to understand why some body parts are preferentially ticklish. (iii) We will ask, in neural terms, what makes tickling fun? We will investigate if rats will voluntarily self-administer ‘electric tickling’, i.e. microstimulation or optogenetic activation of the somatosensory cortex. Our electrical/optogenetic brain stimulation approach will allow imposing the same brain activity without external cues, in the presence of a ‘weak’ cue (a still hand) or in the presence of a ‘strong’ cue (a hand pretending to touch). This way the proposed experiments will elucidate how rats generate the idea of a tickling agent, a mental construct that greatly affects ticklish sensations.

Principal investigators
Brecht, Michael Prof. Dr. (Details) (Animal Physiology/Systems Neurobiology and Neural Computation)

DFG: Sachbeihilfe

Duration of project
Start date: 01/2018
End date: 12/2020

Research Areas
Cognitive Neuroscience, Systemic Neuroscience, Computational Neuroscience, Behaviour

Research Areas
Computational Neuroscience, Neurowissenschaften

Last updated on 2022-08-09 at 15:06