Time Course and Neurophysiological Underpinnings of Metaphor in Literary Context

Conventionality determines the time course of indirect replies comprehension: An ERP study

Indirect language comprehension requires decoding both the literal meaning and the intended meaning of an utterance, in which pragmatic inference is involved. This study tests the role of conventionality in the time course of indirect reply processing by comparing conventional and non-conventional indirect replies with direct reply, respectively. We constructed discourses which consist of a context and a dialogue with one question (e.g., May I buy a necklace for you) and one reply (e.g., I really have too many). The reply utterance was segmented into three phrases and presented orderly for EEG recording, e.g., with the subject as the first phrase (e.g., I), the adverbial as the second phrase (e.g., really), and the predicate as the third phrase (e.g., have too many). Our results showed that for conventional indirect replies, the second phrase elicited a larger anterior negativity, and the third phrase elicited a larger anterior N400 compared with those in direct replies. By contrast, for the non-conventional indirect reply, only the third phrase elicited a larger late negativity than the direct replies. These findings suggest that conventionality determines the time course of the pragmatic inferences for the most relevant interpretation during indirect replies comprehension.

Linguistic signs in action: The neuropragmatics of speech acts

What makes human communication exceptional is the ability to grasp speaker's intentions beyond what is said verbally. How the brain processes communicative functions is one of the central concerns of the neurobiology of language and pragmatics. Linguistic-pragmatic theories define these functions as speech acts, and various pragmatic traits characterise them at the levels of propositional content, action sequence structure, related commitments and social aspects. Here I discuss recent neurocognitive studies, which have shown that the use of identical linguistic signs in conveying different communicative functions elicits distinct and ultra-rapid neural responses. Interestingly, cortical areas show differential involvement underlying various pragmatic features related to theory-of-mind, emotion and action for specific speech acts expressed with the same utterances. Drawing on a neurocognitive model, I posit that understanding speech acts involves the expectation of typical partner follow-up actions and that this predictive knowledge is immediately reflected in mind and brain.

Processing different types of iconicity in Chinese transferred epithet comprehension: An ERP study

Transferred epithet can be regarded as a reflection of semantic markedness since the modifier and the modified conflict with each other and lead to semantic deviation; yet the corresponding processing mechanism is less studied. The present study examined the neurocognitive mechanism of Chinese transferred epithet comprehension by employing ERP technique from the perspective of Iconicity of Markedness. Participants were required to read materials with different types of semantic markedness, namely unmarked linguistic expression (literal sentences) and marked linguistic expression (transferred epithets), and then judge whether the targets were words or pseudo-words. In terms of semantic markedness, the targets are words reflecting the unmarked semantic meaning of literal sentences and marked semantic meaning of transferred epithets respectively. The target words after transferred epithets elicited a larger N400 and a smaller LPC than those in literal sentences. These results suggest that processing sentences with marked and unmarked iconicity involve different neural mechanisms, with the former requiring more cognitive efforts to extract the similarity features.

N400 differences between physical and mental metaphors: The role of Theories of Mind

Whether Theory of Mind (ToM) contributes to metaphor understanding has been largely investigated in language acquisition and decay. Yet we know very little about the role of ToM in real-time processing of metaphors in neurotypical adults. Here, we tested the relationship between ToM and metaphor through Event Related Potentials (ERPs) by capitalizing on the difference between metaphors inviting inferences on physical (Boxers are pandas) vs. mental aspects (Teachers are books). Physical metaphors involved a larger and sustained negativity compared to mental ones. This pattern resembled concreteness effects and suggests that physical metaphors may benefit from both verbal and perceptual information. Moreover, higher scores in the Reading the Mind in the Eyes Test (RMET), but not in the Animation task, were associated with a reduction of the N400 amplitude for both physical and mental metaphors. When exploring the ERP temporal trajectory with Generalized Additive Mixed Modeling, earlier differences between metaphors characterized individuals with higher RMET scores. Among the various ToM components, thus, emotion recognition seems to be involved in the processing of metaphors in general, with an earlier impact on the mental type. These findings highlight the multifaceted nature of metaphor, at the crossroad of language, social and perceptual experience.

Decoding brain activities of literary metaphor comprehension: An event-related potential and EEG spectral analysis

Novel metaphors in literary texts (hereinafter referred to as literary metaphors) seem to be more creative and open-ended in meaning than metaphors in non-literary texts (non-literary metaphors). However, some disagreement still exists on how literary metaphors differ from non-literary metaphors. Therefore, this study explored the neural mechanisms of literary metaphors extracted from modern Chinese poetry by using the methods of Event-Related Potentials (ERPs) and Event-Related Spectral Perturbations (ERSPs), as compared with non-literary conventional metaphors and literal expressions outside literary texts. Forty-eight subjects were recruited to make the semantic relatedness judgment after reading the prime-target pairs in three linguistic conditions. According to the ERPs results, the earliest differences were presented during the time window of P200 component (170–260 ms) in the frontal and central areas, with the amplitude of P200 for literary metaphors more positive than the other two conditions, reflecting the early allocation of attention and the early conscious experience of the experimental stimuli. Meanwhile, significant differences were presented during the time window of N400 effect (430–530 ms), with the waveform of literary metaphors more negative than others in the frontal and central topography of scalp distributions, suggesting more efforts in retrieving conceptual knowledge for literary metaphors. The ERSPs analysis revealed that the frequency bands of delta and theta were both involved in the cognitive process of literary metaphor comprehension, with delta band distributed in the frontal and central scalp and theta band in parietal and occipital electrodes. Increases in the two power bands during different time windows provided extra evidences that the processing of literary metaphors required more attention and effort than non-literary metaphors and literal expressions in the semantic related tasks, suggesting that the cognitive process of literary metaphors was distinguished by different EEG spectral patterns.

Respectfulness-processing revisited: An ERP study of Chinese sentence reading

In Mandarin Chinese, an important manifestation of respectfulness is the use of different forms of second-person pronouns. Jiang et al. (2013) examined the event-related potential (ERP) correlates of processing respectful and plain pronouns in Chinese. However, this study suffered from a few methodological limitations, which restricted both the reliability and functional interpretations of the study’s findings. In the present study, we resolved these limitations and further investigated the neurocognitive mechanisms of processing the respectfulness of pronouns. In the present study, participants read 160 critical Chinese sentences with a second-person pronoun (ni or nin) that was either consistent or inconsistent with its prior sentence context in terms of respectfulness, as well as 240 filler sentences. Unlike the previous study that reported a 300–500 ms negative response (N400) for both types of inconsistent pronouns, a sustained positive response for Nin inconsistent and a sustained negativity response for Ni inconsistent in the late time window, the present study found an N400 response and late sustained negativity for Nin inconsistent, but not for Ni inconsistent. Furthermore, the cluster-based permutation showed a significant negative cluster for Nin inconsistent, extending from 432–622 ms. We related this negative response for Nin inconsistent with recent accounts of the N400 and late negativity. Finally, the absence of the ERP effect for the Ni condition was linked to the role of the pragmatic property of Ni.

The Role of Literal Features During Processing of Novel Verbal Metaphors

When a word is used metaphorically (for example “walrus” in the sentence “The president is a walrus”), some features of that word's meaning (“very fat,” “slow-moving”) are carried across to the metaphoric interpretation while other features (“has large tusks,” “lives near the north pole”) are not. What happens to these features that relate only to the literal meaning during processing of novel metaphors? In four experiments, the present study examined the role of the feature of physical containment during processing of verbs of physical containment. That feature is used metaphorically to signify difficulty, such as “fenced in” in the sentence “the journalist's opinion was fenced in after the change in regime.” Results of a lexical decision task showed that video clips displaying a ball being trapped by a box facilitated comprehension of verbs of physical containment when the words were presented in isolation. However, when the verbs were embedded in sentences that rendered their interpretation metaphorical in a novel way, no such facilitation was found, as evidenced by two eye-tracking reading studies. We interpret this as suggesting that features that are critical for understanding the encoded meaning of verbs but are not part of the novel metaphoric interpretation are ignored during the construction of metaphorical meaning. Results and limitations of the paradigm are discussed in relation to previous findings in the literature both on metaphor comprehension and on the interaction between language comprehension and the visual world.

Affective and psycholinguistic norms for German conceptual metaphors (COMETA)

Figurative expressions have been shown to play a special role in evoking affective responses, as compared to their literal counterparts. This study provides the first database of conceptual metaphors that includes ratings of affective properties beyond psycholinguistic properties. To allow for the investigation of natural reading processes, 64 natural stories were created, half of which contained two or three conceptual metaphors that relied on the same mapping, whereas the other half contained the metaphors' literal counterparts. To allow for tighter control and manipulation of the different properties, 120 isolated sentences were also created, half of which contained one metaphorical word, which was replaced by its literal rendering in the other half. All stimuli were rated for emotional valence, arousal, imageability, and metaphoricity, and the pairs of metaphorical and literal stimuli were rated for their similarity in meaning. A measure of complexity was determined and computed. The stories were also rated for naturalness and understandability, and the sentences for familiarity. Differences between the metaphorical and literal stimuli and relationships between the affective and psycholinguistic variables were explored and are discussed in light of extant empirical research. In a nutshell, the metaphorical stimuli were rated as being higher in emotional arousal and easier to imagine than their literal counterparts, thus confirming a role of metaphor in evoking emotion and in activating sensorimotor representations. Affective variables showed the typical U-shaped relationship consistently found in word databases, whereby increasingly positive and negative valence is associated with higher arousal. Finally, interesting differences between the stories and sentences were observed.

Re-Representing Metaphor: Modeling Metaphor Perception Using Dynamically Contextual Distributional Semantics

In this paper, we present a novel context-dependent approach to modeling word meaning, and apply it to the modeling of metaphor. In distributional semantic approaches, words are represented as points in a high dimensional space generated from co-occurrence statistics; the distances between points may then be used to quantifying semantic relationships. Contrary to other approaches which use static, global representations, our approach discovers contextualized representations by dynamically projecting low-dimensional subspaces; in these ad hoc spaces, words can be re-represented in an open-ended assortment of geometrical and conceptual configurations as appropriate for particular contexts. We hypothesize that this context-specific re-representation enables a more effective model of the semantics of metaphor than standard static approaches. We test this hypothesis on a dataset of English word dyads rated for degrees of metaphoricity, meaningfulness, and familiarity by human participants. We demonstrate that our model captures these ratings more effectively than a state-of-the-art static model, and does so via the amount of contextualizing work inherent in the re-representational process.