Insular cortex activity and the evocation of laughter.
The insular cortex is fundamentally involved in the processing of interoceptive information. It has been postulated that the integrative monitoring of the bodily responses to environmental stimuli is crucial for the recognition and experience of emotions. Because emotional arousal is known to be closely coupled to functions of the anterior insula, we suspected laughter to be associated primarily with neuronal activity in this region. An anatomically constrained re-analysis of our imaging data pertaining to ticklish laughter, to inhibited ticklish laughter, and to voluntary laughter revealed regional differences in the levels of neuronal activity in the posterior and mid-/anterior portions of the insula. Ticklish laughter was associated specifically with right ventral anterior insular activity, which was not detected under the other two conditions. Hence, apparently, only laughter that is evoked as an emotional response bears the signature of autonomic arousal in the insular cortex.
Anatomy and Program in Neuroscience, Department of Medicine, University of Fribourg, CH-1700, Fribourg, Switzerland.
Elise
E
Wattendorf
Department of Neurosurgery, University Hospital, University of Basel, CH-4031, Basel, Switzerland.
Birgit
B
Westermann
Functional Imaging Unit, Diagnostic Radiology, University Hospital, University of Greifswald, D-17489, Greifswald, Germany.
Martin
M
Lotze
Anatomy and Program in Neuroscience, Department of Medicine, University of Fribourg, CH-1700, Fribourg, Switzerland.
Klaus
K
Fiedler
Anatomy and Program in Neuroscience, Department of Medicine, University of Fribourg, CH-1700, Fribourg, Switzerland.
Marco R
MR
Celio
D002540:Cerebral Cortex / Q000502:physiology*; D006801:Humans; D007845:Laughter / Q000502:physiology*
anterior insula; autonomic; emotional arousal; fMRI; insular cortex; laughter; positive emotion; tickle