Hemispheric asymmetry and pun comprehension: when cowboys have sore calves

Humor in autism spectrum disorders: A systematic review

OBJECTIVES

Humor is essential to social relationships. Its use and understanding appear to be impaired in people with Autism Spectrum Disorder (ASD). The main objective was to review the existing literature on the detection, understanding and use of humor in persons with ASD. The secondary objective involved exploring assessment scales and specific intervention tools.

METHODS

A systematic review of the literature was carried out on all available French and English scientific papers about humor - including irony - in persons with ASD up to November 2021. We extracted 552 references and included 43 articles from six databases.

RESULTS

Studies suggest that those with ASD can detect audiovisual and written humor. Understanding humor was impaired in writing and when using pure auditory stimuli and non-verbal cartoons. For irony, the results indicated a lower detection of quality and less understanding in speaking but not in writing. Regarding its use, in terms of expression, people with ASD use benevolent humor less often and do not consider humor as a key source of satisfaction with life, as opposed to the control group.

CONCLUSIONS

It appears that it would be worthwhile to develop standardized humor detection and assessment tools specific to persons with ASD. Practical strategies that focus on humor ability could be worth developing, either individually or in groups.

tDCS of right-hemispheric Wernicke's area homologue affects contextual learning of novel lexicon

Numerous studies have shown robust evidence of the right hemisphere's involvement in the language function, for instance in the processing of intonation, grammar, word meanings, metaphors, etc. However, its role in lexicon acquisition remains obscure. We applied transcranial direct current stimulation (tDCS) over the right-hemispheric homologue of Wernicke's area to assess its putative involvement in the processing of different types of novel semantics. After receiving 15 min of anodal, cathodal, or sham (placebo) tDCS, three groups of healthy participants learnt novel concrete and abstract words in the context of short stories. Learning outcomes were assessed using a battery of tests immediately after this contextual learning session and 24 h later. As a result, an inhibitory effect of cathodal tDCS and a facilitatory effect of anodal tDCS were found for abstract word acquisition only. We also found a significant drop in task performance on the second day of the assessment for both word types in all the stimulation groups, suggesting no significant influence of tDCS on the post-learning consolidation of new memory traces. The results suggest an involvement of Wernicke's right-hemispheric counterpart in initial encoding (but not consolidation) of abstract semantics, which may be explained either by the right hemispheres direct role in processing lexical semantics or by an indirect impact of tDCS on contralateral (left-hemispheric) cortical areas through cross-callosal connections.

Contextual Support for Less Salient Homophones and Pun Humor Appreciation: Evidence From Eye Movements in Reading Chinese Homophone Puns

Punning is an important means of creating humorous effects by intentionally exploiting semantic ambiguity. Previous psycholinguistic research on puns has mainly focused on the process of meaning retrieval in homograph puns, while it is still not entirely clear how readers dynamically utilize contextual information to understand homophone puns. In the current investigation, 68 native Chinese participants were recruited to read three types of experimental sentences while their eye movements were recorded: (1) the homophone-pun sentences where the less salient homophone was visually presented, (2) the homophone-salient sentences where the salient homophone was used, and (3) the homophone-error sentences where the critical context noun in the homophone puns was replaced with an unrelated word. Humor rating results of the homophone puns and the homophone-salient sentences demonstrated that the less salient homophones rather than the salient ones elicited much larger humor responses when presented visually in the same potential pun context. In addition, the reverse fixation pattern in the homophone area and the spill-over region also suggested that meanings of the salient homophones were more recoverable even when not presented visually. Statistical analyses of the homophone puns and the homophone-error sentences showed that the semantic relatedness between the critical context noun and the less salient homophone could significantly predict the humor rating scores of Chinese readers. Taken together, less salient homophones need to receive more contextual support to balance out the advantages of salient homophones before generating a humorous pun interpretation.

Uncover the Offensive Side of Disparagement Humor: An fMRI Study

Disparagement humor is a kind of humor that denigrates, belittles an individual or a social group. In the aim to unveil the offensive side of these kinds of jokes, we have run an event-related fMRI study asking 30 healthy volunteers to judge the level of fun of a series of verbal stimuli that ended with a sentence that was socially inappropriate but funny (disparagement joke -DJ), socially inappropriate but not funny (SI) or neutral (N). Behavioral results showed disparagement jokes are perceived as funny and at the same time offensive. However, the level of offense in DJ is lower than that registered in SI stimuli. Functional data showed that DJ activated the insula, the SMA, the precuneus, the ACC, the dorsal striatum (the caudate nucleus), and the thalamus. These activations suggest that in DJ a feeling of mirth (and/or a desire to laugh) derived from the joke (e.g., SMA and precuneus) and the perception of the jokes’ social inappropriateness (e.g., ACC and insula) coexist. Furthermore, DJ and SI share a common network related to mentalizing and to the processing of negative feelings, namely the medial prefrontal cortex, the putamen and the right thalamus.

The Effect of Salience on Chinese Pun Comprehension: A Visual World Paradigm Study

The present study adopted the printed-word visual world paradigm to investigate the salience effect on Chinese pun comprehension. In such an experiment, participants listen to a spoken sentence while looking at a visual display of four printed words (including a semantic competitor, a phonological competitor, and two unrelated distractors). Previous studies based on alphabetic languages have found robust phonological effects (participants fixated more at phonological competitors than distractors during the unfolding of the spoken target words), while controversy remains regarding the existence of a similar semantic effect. A recent Chinese study reported reliable semantic effects in two experiments using this paradigm, suggesting that Chinese participants could actively map the semantic input from the auditory modality with the semantic information retrieved from printed words. In light of their study, we designed an experiment with two conditions: a replication condition to test the validity of using the printed-word world paradigm in Chinese semantic research, and a pun condition to assess the role played by salience during pun comprehension. Indeed, global analyses have revealed robust semantic effects in both experimental conditions, where participants were found more attracted to the semantic competitors than to the distractors with the emergence of target words. More importantly, the local analyses from the pun condition have shown that the participants were more attracted to the semantic competitors related to the salient meaning of the ambiguous word in a pun than to those related to the less salient meanings within 200 ms after target word offset. This finding suggests that the salient meaning of the ambiguous word in a pun is activated and assessed faster than its less salient counterpart. The initial advantage observed in the present study is consistent with the prediction of the graded salience hypothesis rather than the direct access model.

The N400 elicited by homonyms in puns: Two primes are not better than one

To comprehend a pun involving a homonym (e.g., The prince with a bad tooth got a crown), both meanings of the homonym must be accessed and selected. Previous ERP studies have shown that the N400 reflects lexicosemantic processing, but none have directly investigated the N400 elicited by homonyms in the unique context of puns. Here, N400 priming effects showed that the dual context of puns (e.g., the primes prince and tooth) did not facilitate homonym processing in comparison to single dominant biasing (e.g., The prince with a bad leg got a crown) or subordinate biasing (e.g., The adult with a bad tooth got a crown) conditions. However, homonyms did elicit a less negative N400 (i.e., priming) in the pun condition in comparison to the neutral context condition (e.g., The adult with a bad leg got a crown). These findings are interpreted in terms of the dominant advantage and subordinate bias effect posited by the reordered access model of homonym processing, and in terms of N400 amplitude as an index of how consistently various sources of semantic featural information converge on one lexical item, even when two lexical items must be activated for comprehension.

Listening to Puns Elicits the Co-Activation of Alternative Homophone Meanings during Language Production

Recent evidence suggests that lexical-semantic activation spread during language production can be dynamically shaped by contextual factors. In this study we investigated whether semantic processing modes can also affect lexical-semantic activation during word production. Specifically, we tested whether the processing of linguistic ambiguities, presented in the form of puns, has an influence on the co-activation of unrelated meanings of homophones in a subsequent language production task. In a picture-word interference paradigm with word distractors that were semantically related or unrelated to the non-depicted meanings of homophones we found facilitation induced by related words only when participants listened to puns before object naming, but not when they heard jokes with unambiguous linguistic stimuli. This finding suggests that a semantic processing mode of ambiguity perception can induce the co-activation of alternative homophone meanings during speech planning.

Arithmetic memory networks established in childhood are changed by experience in adulthood

Adult bilinguals show stronger access to multiplication tables when using the language in which they learned arithmetic during childhood (LA+) than the other language (LA-), implying language-specific encoding of math facts. However, most bilinguals use LA+ throughout their life, confounding the impact of encoding and use. We tested if using arithmetic facts in LA- could reduce this LA- disadvantage. We measured event related brain potentials while bilingual teachers judged the correctness of multiplication problems in each of their languages. Critically, each teacher taught arithmetic in either LA+ or LA-. Earlier N400 peak latency was observed in both groups for the teaching than non-teaching language, showing more efficient access to these facts with use. LA+ teachers maintained an LA+ advantage, while LA- teachers showed equivalent N400 congruency effects (for incorrect versus correct solutions) in both languages. LA- teachers also showed a late positive component that may reflect conflict monitoring between their LA+ and a strong LA-. Thus, the LA- disadvantage for exact arithmetic established in early bilingual education can be mitigated by later use of LA-.

Event-related potentials indicate context effect in reading ambiguous words

The aim of the study was a comparison of lexical and contextual factors in understanding ambiguous words in German. First, a sample of native speakers selected 56 words having maximally strong differences between a dominant and a subordinate meaning. After this, another sample from the same population was visually presented with sentences that activated dominant or subordinate meanings of the words and were accompanied by probes associated with dominant or subordinate meanings. This resulted in a crossed design with two factors: sentence dominant vs. sentence subordinate and probe dominant vs. probe subordinate. An analysis of event-related brain potentials revealed a large, long-lasting and highly-significant N400 wave whenever the meaning of the probe was incongruent with the meaning of the sentence and the lack of this wave whenever the two meanings were congruent. In the typical N400 space and time, the effect was independent of whether the lexical word meaning was dominant or subordinate. At other sites and times, however (e.g., at lateral frontal electrodes F7/F8, and after 700ms), the congruence effect was significant after dominant sentences only. The data indicate that lexical factors have a rather limited influence on the activation of a particular meaning of ambiguous words. A strong context can virtually override even a very strong difference in the preference for different meanings.

Structural asymmetry of anterior insula: behavioral correlates and individual differences

The current study investigated behavioral correlates of structural asymmetry of the insula, and traditional perisylvian language regions, in a large sample of young adults (N=200). The findings indicated (1) reliable leftward surface area asymmetry of the anterior insula, (2) association of this asymmetry with divided visual field lateralization of visual word recognition, and (3) modulation of the correlation of structural and linguistic asymmetry by consistency of hand preference. Although leftward asymmetry of cortical surface area was observed for the anterior insula, pars opercularis and triangularis, and planum temporale, only the anterior insula asymmetry was associated with lateralized word recognition. We interpret these findings within the context of recent structural and functional findings about the human insula. We suggest that leftward structural lateralization of earlier developing insular cortex may bootstrap asymmetrical functional lateralization even if the insula is only a minor component of the adult language network.

"The archeologist's career ended in ruins": hemispheric differences in pun comprehension in autism

Appropriate interpretation of figurative language involves inferring the speaker's intent by integrating word meaning with context. In disorders like autism, understanding intended and contextual meanings in language may pose a challenge. Such difficulties are prevalent even when individuals exhibit otherwise fluent language ability (Szatmari et al., 1990). A pun is a rhetorical technique in which a speaker deliberately invokes multiple meanings through a word or phrase likely resulting in a joke. Comprehending puns may involve identifying multiple meanings of a word, embedding it in right contexts, and understanding the underlying humor. This fMRI study investigated the brain responses associated with figures of speech like puns. In the fMRI scanner, participants read sentences containing puns (e.g. To write with a broken pencil is pointless) and control sentences (literal meaning) presented in a blocked design format. The participants' task was to silently read and understand one meaning (in the literal condition) or two meanings (in the pun condition). Participants with autism, relative to typical controls, showed an increase in overall activation while comprehending sentences containing puns, particularly within the right hemisphere as well as in relatively posterior brain areas. Overall, there was reduced response in left hemisphere areas, reduced response to humor, and more distributed recruitment of regions in autism relative to control participants. We also examined the relationship between symptom severity in autism and verbal ability with brain responses to pun comprehension finding negative and positive correlations respectively. Overall, the results from the present study suggest that individuals with autism resort to altered neural routes in comprehending language in general, and figurative language in particular.

The role of the right hemisphere in speech act comprehension

In this research the role of the RH in the comprehension of speech acts (or illocutionary force) was examined. Two split-screen experiments were conducted in which participants made lexical decisions for lateralized targets after reading a brief conversation remark. On one-half of the trials the target word named the speech act performed with the preceding conversation remark; on the remaining trials the target did not name the speech act that the remark performed. In both experiments, lexical decisions were facilitated for targets representing the speech act performed with the prior utterance, but only when the target was presented to the left visual field (and hence initially processed by the RH) and not when presented to the right visual field. This effect occurred at both short (Experiment 1: 250 ms) and long (Experiment 2: 1000 ms) delays. The results demonstrate the critical role played by the RH in conversation processing.

Stop laughing! Humor perception with and without expressive suppression

The neurophysiological study of emotion regulation focused on the strategy of reappraisal-i.e., the cognitive reinterpretation of a stimulus. Reappraisal reduces emotional expression, the experience of both negative and positive feelings, and the amplitude of an event-related potential (ERP)-the late positive potential (LPP). In contrast, the strategy of expressive suppression (ES), being the inhibition of emotional expression, has been reported to reduce subjective feelings of positive, but not negative emotion, and has not yet been investigated with ERPs. We focused on the LPP to assess the correlates of ES in the context of humor perception. Twenty-two female participants rated sequences of humorous (H) and non-humorous (NH) pictures, while their zygomaticus muscle was recorded. A spontaneous (SP) condition, in which participants attended naturally to the pictures, resulted in higher ratings of funniness, increased smiling, and increased LPP amplitude for H compared to NH stimuli. An ES condition, in which participants suppressed their facial reactions, resulted in reduced smiling, without affecting subjective ratings. LPP amplitude did not differ between H and NH stimuli during ES, suggesting equal allocation of processing resources to both stimuli. These results suggest that, similarly to reappraisal, ES modifies the way the brain processes positive emotional stimuli.

Summing it up: semantic activation processes in the two hemispheres as revealed by event-related potentials

The coarse coding hypothesis suggests that semantic activation is broader in the right hemisphere, affording it an advantage over the left hemisphere for the activation of distantly related concepts or multiple meanings of lexically ambiguous words. Behavioral studies investigating coarse coding have yielded mixed results, perhaps in part because such measures sum across multiple processing stages. To more directly tap into the semantic activation processes that are the focus of the coarse coding hypothesis, the current study combined a visual half-field summation-priming paradigm with the measurement of event-related potentials (ERPs). Two primes converged onto a lateralized, unambiguous target (e.g., lion-stripes-tiger) or diverged onto different meanings of a lateralized, ambiguous target (e.g., kidney-piano-organ); in both cases, the primes were related to one another only through the target. In two experiments, participants either made lexical decisions to the targets or made a semantic-relatedness judgment between primes and target. Priming was measured as reductions in the amplitude of the N400, an ERP component that has been specifically linked to meaning activation and that showed semantic-level priming patterns in both of the tasks used in the present study. Counter to the predictions of the coarse coding hypothesis, equivalent N400 summation priming was observed for targets in the two visual fields, in both types of triplets and in both experiments. Thus, the current results fail to support the hypothesis that semantic activation patterns differ in the two hemispheres and point, instead, to other sources for observed asymmetries in verbal processing.

The divided visual world paradigm: eye tracking reveals hemispheric asymmetries in lexical ambiguity resolution

Eye tracking was combined with the visual half-field procedure to examine hemispheric asymmetries in meaning selection and revision. In two experiments, gaze was monitored as participants searched a four-word array for a target that was semantically related to a lateralized ambiguous or unambiguous prime. Primes were preceded by a related or unrelated centrally-presented context word. In Experiment 1, unambiguous primes were paired with concordant weakly-related context words and strongly-related targets that were similar in associative strength to discordant subordinate-related context words and dominant-related targets in the ambiguous condition. Context words and targets were reversed in Experiment 2. A parallel study involved the measurement of event-related potentials (ERPs; Meyer, A. M., and Federmeier, K. D., 2007. The effects of context, meaning frequency, and associative strength on semantic selection: distinct contributions from each cerebral hemisphere. Brain Res. 1183, 91-108). Similar to the ERP findings, gaze revealed context effects for both visual fields/hemispheres when subordinate-related targets were presented: initial gaze revealed meaning activation when an unrelated context was utilized, whereas later gaze also revealed activation in the discordant context, indicating that meaning revision had occurred. However, eye tracking and ERP measures diverged when dominant-related targets were presented: for both visual fields/hemispheres, initial gaze indicated the presence of meaning activation in the discordant context, and, for the right hemisphere, discordant context information actually facilitated gaze relative to unrelated context information. These findings are discussed with respect to the activeness of the task and hemispheric asymmetries in the flexible use of context information.

Theoretical Considerations for Understanding "Understanding" by Adults With Right Hemisphere Brain Damage

This article reviews and evaluates leading accounts of narrative comprehension deficits in adults with focal damage to the right cerebral hemisphere (RHD). It begins with a discussion of models of comprehension, which explain how comprehension proceeds through increasingly complex levels of representation. These models include two phases of comprehension processes, broad activation of information as well as pruning and focusing interpretation of meaning based on context. The potential effects of RHD on each processing phase are reviewed, focusing on factors that range from relatively specific (e.g., how the right versus the left hemisphere activate word meanings; how the right hemisphere is involved in inferencing) to more general (the influence of cognitive resource factors; the role of suppression of contextually-irrelevant information). Next, two specific accounts of RHD comprehension difficulties, coarse coding and suppression deficit, are described. These have been construed as opposing processes, but a possible reconciliation is proposed related to the different phases of comprehension and the extent of meaning activation. Finally, the article addresses the influences of contextual constraint on language processing and the continuity of literal and nonliteral language processing, two areas in which future developments may assist our clinical planning.

What's "right" in language comprehension: ERPs reveal right hemisphere language capabilities

Although the term "nonverbal" is often applied to the right cerebral hemisphere (RH), a growing body of work indicates that the RH can comprehend language and, indeed, that it makes critical contributions to normal language functions. Reviewed here are studies that have examined RH language capabilities by combining visual half-field presentation methods with event-related potential (ERP) measures. Because they afford temporal and functional specificity and can be obtained as participants simply process language for meaning, ERPs provide especially valuable insights into RH language functions. Such studies suggest that the RH appreciates word and message-level meaning information, and that it may play a particularly important role in the processing of relatively unpredictable semantic relationships. In addition, this work suggests that patterns observed for everyday language processing may often be an emergent property of multiple, distinct mechanisms operating in parallel as the left and right hemispheres jointly comprehend language.

Multiple priming of lexically ambiguous and unambiguous targets in the cerebral hemispheres: the coarse coding hypothesis revisited

The coarse coding hypothesis postulates that the cerebral hemispheres differ in their breadth of semantic activation, with the left hemisphere activating a narrow, focused semantic field and the right weakly activating a broader semantic field. In support of coarse coding, studies investigating priming for multiple senses of a lexically ambiguous word have reported a right hemisphere benefit. However, studies of mediated priming have failed to find a right hemisphere advantage for processing distantly linked, unambiguous words. To address this debate, the present study made use of a multiple priming paradigm in which two primes either converged onto the single meaning of an unambiguous, lexically associated target (LION-STRIPES-TIGER) or diverged onto different meanings of an ambiguous target (KIDNEY-PIANO-ORGAN). In two experiments, participants either made lexical decisions to lateralized targets (Experiment 1) or made a semantic relatedness judgment between primes and targets (Experiment 2). In both tasks, for both ambiguous and unambiguous triplets we found equivalent priming strengths and patterns across the two visual fields, counter to the predictions of the coarse coding hypothesis. Priming patterns further suggested that both hemispheres made use of lexical level representations in the lexical decision task and semantic representations in the semantic judgment task.