Neural Correlates of Contrast and Humor: Processing Common Features of Verbal Irony

Abstract

Irony is a kind of figurative language used by a speaker to say something that contrasts with the context and, to some extent, lends humor to a situation. However, little is known about the brain regions that specifically support the processing of these two common features of irony. The present study had two main aims: (i) investigate the neural basis of irony processing, by delivering short ironic spoken sentences (and their literal counterparts) to participants undergoing fMRI; and (ii) assess the neural effect of two irony parameters, obtained from normative studies: degree of contrast and humor appreciation. Results revealed activation of the bilateral inferior frontal gyrus (IFG), posterior part of the left superior temporal gyrus, medial frontal cortex, and left caudate during irony processing, suggesting the involvement of both semantic and theory-of-mind networks. Parametric models showed that contrast was specifically associated with the activation of bilateral frontal and subcortical areas, and that these regions were also sensitive to humor, as shown by a conjunction analysis. Activation of the bilateral IFG is consistent with the literature on humor processing, and reflects incongruity detection/resolution processes. Moreover, the activation of subcortical structures can be related to the reward processing of social events.

Altered Neural Activity during Irony Comprehension in Unaffected First-Degree Relatives of Schizophrenia Patients—An fMRI Study

“…We found a left temporal lobe activation with a local maximum in the left TP, a cluster which reaches the posterior STS (Uchiyama et al, 2006 ; Shibata et al, 2010 ), as well as activations in the right STS (a cluster which reaches the right TP), in the bilateral DMPFC (BA 10), with a local maximum in the left hemisphere (Uchiyama et al, 2006 ; Wang et al, 2006a , b ; Wakusawa et al, 2007 ; Shibata et al, 2010 ), and in the bilateral posterior cingulum, with a local maximum in the left hemisphere. In several studies, some of these areas were found active not only in irony, but also in ToM processing (Cavanna and Trimble, 2006 ; Abu-Akel and Shamay-Tsoory, 2011 ; Spreng and Mar, 2012 ), which is in line with the assumption of previous studies and a meta-analysis that ToM network is active while someone is understanding verbal irony (Bohrn et al, 2012 ; Spotorno et al, 2012 ; Obert et al, 2016 ; Van Ackeren et al, 2016 ).…”

“…Since irony is a special figure of thought, depending upon different cognitive operations, many studies found activations in some typical regions of the ToM network (Uchiyama et al, 2006 ; Wang et al, 2006b ; Shamay-Tsoory and Aharon-Peretz, 2007 ; Wakusawa et al, 2007 ; Rapp et al, 2010 , 2012 ; Shibata et al, 2010 ; Bohrn et al, 2012 ; Spotorno et al, 2012 ; Bosco et al, 2017b ), as well as of the semantic and executive system (Eviatar and Just, 2006 ; Rapp et al, 2010 , 2012 ; Spotorno et al, 2012 ; Bosco et al, 2017b ). In line with previous suggestions (Spotorno et al, 2012 ; Obert et al, 2016 ) Van Ackeren et al ( 2016 ) demonstrated using connectivity analysis that ToM and language networks interact while interpreting indirect speech acts.…”

“…More specifically, BOLD responses in the left pars triangularis of the IFG (BA 45) have been classically detected during semantic processing of speech (Özyürek, 2014 ). In addition, in previous studies this region has been considered to play a role in semantic processing of irony (Rapp et al, 2012 ; Obert et al, 2016 ; Bosco et al, 2017b ).…”

“…The SG also activated the pars triangularis of the left IFG. This region has been considered to play a semantic role in irony processing (Rapp et al, 2012 ; Obert et al, 2016 ). It is presumed that the left IFG is involved in the recognition of contradictory information between the context and the non-literal sentence meaning, and it works together with the right IFG, which is responsible for the detection of the incongruity between the statement and the prosody (Obert et al, 2016 ).…”

“…The RG showed activations in the posterior part of the left STG, in the right STS and in the pars triangularis of left IFG during understanding the ironic statement. BOLD responses in the left STG and in the left IFG were observed during semantic processing (Giora et al, 2000 ; Uchiyama et al, 2006 ; Wang et al, 2006b ; Shamay-Tsoory and Aharon-Peretz, 2007 ), and during the semantic integration process in irony interpretation (Rapp et al, 2012 ; Obert et al, 2016 ). In addition, STS was also found to contribute to irony processing, explained as a higher-order linguistic processing (Shibata et al, 2010 ).…”