**2. Recognizing speech acts and action-related networks**

Language is a powerful tool to communicate the speaker's intended action. The neural correlates of speech were examined in a study in which the participants were presented with videos with the same critical utterances [21] embedded in different communicative scenarios (to name or to request the possession of the objects from the conversational partners). Speech (or communicative) acts are various in terms of one's possession of action-related and socio-interactive knowledge, which are considered to be linked with the action perception and prediction in the fronto-central sensorimotor cortex [22], the human homolog of the mirroring system across premotor inferior frontal and anterior inferior parietal cortex [23], and the mentalizing networks [24] over mPFC, ACC, and TPJ. The speech act of naming or requesting something does not differ according to the linguistic utterance used to perform the action or the physical setting during the communicative event (e.g., object and the communicative partners), but in the expectation of the action sequences in which the speech act is embedded (e.g., to point to the target to be named or to fetch the object to fulfill the request) and the intentions and assumptions of communicating partners (e.g., the speaker's desire to obtain the object during request). The request activated the bilateral premotor, the left IFG, and temporo-parietal areas that support the prediction of the subsequent actions following speech and representation of social interactive knowledge. However, the naming activated the left angular gyrus that establishes the referential relationship between a lexical item and the referred targets. A similar study focusing on the indirect request, such as *it is cold in here* used to request to close the window, as compared with the same expression for informing others of the temperature. The visual context that accompanied the utterances differed between the informing (images of a desert landscape) and the requesting (images of a window). Stronger activation in the indirect requests was observed in the fronto-central action system as well as the parietal areas related with the mirror neuron intention understanding; and in the mPFC, TPJ for theory of mind (ToM) processing [24].

Another fMRI study focused on the role of modality-preferential sensorimotor areas in processing meaning of abstract emotion words, such as "love," and mental words, such as "thought" [25]. While the prefrontal cortex (e.g., the dorsal lateral and prefrontal areas) served to activate the multimodal meanings regardless of word types, the sensorimotor regions (e.g., premotor areas, [26]; left posterior IFG and MFG, [27]; rostral part of ACC, [28]) were selectively engaged more in the abstract words. Participants read silently abstract emotional and mental nouns along with concrete action-related words. The regional-of-interest analysis showed that the face motor areas in the left precentral somatotopy was involved when the mental nouns and the face-related action words were encountered, while both the precentral hand and face motor areas were recruited when participants read abstract emotion words [29]. The sensorimotor systems in semantic processing are not restricted to the concrete action words but should be extended to some mental concepts. The causal role of prefrontal regions in the abstract emotion and interpersonal mental words were also demonstrated. For example, patients with a focal lesion of the left supplementary motor area (SMA) showed selective deficit in processing abstract emotional nouns. The interpersonal words (such as "convince," [30]) were found to activate the medial prefrontal, post-cingulate cortex (PCC), and orbitofrontal cortex, areas identified to be involved in mentalizing and social cognition processes. The prefrontal region, especially those which are necessary for integration of social knowledge and one's action, participated in the understanding of communicative (speech) acts.

as indirect response to: *Are you fluent in any foreign languages*? vs. direct response to *What are your plans after graduation*?), activated mPFC, bilateral IFG, bilateral TPJ, and bilateral MTG in both conversation settings. The ventral salience network (dorsal portion of insula and anterior cingulate cortex (ACC)) was additionally involved in certain social scenarios when the participant was addressed directly. These findings suggest that the face-saving indirect languages engage perspective-taking and discourse mechanisms associated with the increased inferential complexity which may be irrelevant to whether the speaker was the first person or third person involved in the comprehension. Moreover, affective processing mechanism which determines whether the participant is the direct recipient of the address, with the regions encoding emotional salience involved when the listener's evaluative process is stronger as the direct addressee toward the indirect reply. These findings suggest that the social inference and selection of the appropriate meaning may serve as crucial mechanisms that draw upon medial prefrontal cortex to resolve any types of unspecified or implicit meanings which are contextualized, including the derivation of the pragmatic implicatures in nonliteral statements.

Language is a powerful tool to communicate the speaker's intended action. The neural correlates of speech were examined in a study in which the participants were presented with videos with the same critical utterances [21] embedded in different communicative scenarios (to name or to request the possession of the objects from the conversational partners). Speech (or communicative) acts are various in terms of one's possession of action-related and socio-interactive knowledge, which are considered to be linked with the action perception and prediction in the fronto-central sensorimotor cortex [22], the human homolog of the mirroring system across premotor inferior frontal and anterior inferior parietal cortex [23], and the mentalizing networks [24] over mPFC, ACC, and TPJ. The speech act of naming or requesting something does not differ according to the linguistic utterance used to perform the action or the physical setting during the communicative event (e.g., object and the communicative partners), but in the expectation of the action sequences in which the speech act is embedded (e.g., to point to the target to be named or to fetch the object to fulfill the request) and the intentions and assumptions of communicating partners (e.g., the speaker's desire to obtain the object during request). The request activated the bilateral premotor, the left IFG, and temporo-parietal areas that support the prediction of the subsequent actions following speech and representation of social interactive knowledge. However, the naming activated the left angular gyrus that establishes the referential relationship between a lexical item and the referred targets. A similar study focusing on the indirect request, such as *it is cold in here* used to request to close the window, as compared with the same expression for informing others of the temperature. The visual context that accompanied the utterances differed between the informing (images of a desert landscape) and the requesting (images of a window). Stronger activation in the indirect requests was observed in the fronto-central action system as well as the parietal areas related with the mirror neuron intention understanding; and in the mPFC,

**2. Recognizing speech acts and action-related networks**

68 Prefrontal Cortex

TPJ for theory of mind (ToM) processing [24].
