A central question in the cognitive neuroscience of language is how meaning is represented and accessed in the brain during language comprehension and production. It has been well established that language and perception interact in the brain and in behavior. For instance, even after the presentation of a single word, semantically related words are processed more quickly (i.e., primed), possibly due to spreading activation of features shared between the two words (Anderson, 1983), and semantic priming occurs across mixed input and target modalities, such that pictures can also prime related words, and vice versa (Sperber et al., 1979). In the domain of action perception, a great deal of research supports the notion that visually perceiving actions and processing language about actions rely on overlapping representations in the mind and brain (Barsalou, 1999; Glenberg and Kaschak, 2002; Bergen et al., 2007). Here, we set out to explore the relationship between processing language about biological motion and visually perceiving it. To this end, we asked how a visual prime depicting biological motion would affect reading times of literal and metaphorical language containing action verbs with either a close or more distant semantic relationship to the prime.

Literal meaning is dependent not only on information stored in semantic memory but also on the physical context, including representations that are grounded in perception and action (Barsalou, 1999). Glenberg and Kaschak (2002) found that when people processed linguistic information about motion directed toward the self (e.g., Close the drawer), compared to away from the self (e.g., Open the drawer), they were faster to respond using a button in that direction (that is, closer to the self, compared to farther away). A subsequent study investigating this action compatibility effect (ACE) further probed its timing and found that when participants did not know which response button they would use prior to reading such sentences, compatibility effects were no longer present (Borreggine and Kaschak, 2006). These findings minimally suggest that processing language about actions can rely upon representations overlapping with those used to process the physical actions themselves but that the timecourse of such activations is sensitive to context.

Other studies have shown that literal language about objects and space can both facilitate (e.g., Stanfield and Zwaan, 2001) and inhibit (e.g., Richardson et al., 2003; Bergen et al., 2007, 2010) similar behavioral responses, largely dependent on the timing between primes and the response measure. Stanfield and Zwaan (2001) had participants read sentences about objects which implied an object's orientation (either horizontal, e.g., John put the pencil in the drawer, or vertical, e.g., John put the pencil in the cup). Next, participants were shown a picture of an object in either a horizontal or vertical orientation and were asked whether it had been mentioned in the preceding sentence. They observed that participants responded more quickly when the object matched the implied orientation of the object mentioned in the sentences.

Bergen et al. (2007) investigated the extent to which visual imagery is used in understanding both literal and metaphorical language and found interference-type effects. After reading a short sentence, participants categorized a shape presented in either the upper or lower part of the screen. When the sentence contained concrete verbs or nouns which were semantically associated with the concepts “up” (e.g., The cork rocketed) vs. “down” (e.g., The glass fell), participants were systematically slower to make a decision about an object presented in the associated part of the screen. These findings support the hypothesis that participants use visual imagery to process literal language about space. Taken together with other behavioral results suggesting that people use mental imagery or simulations when processing information about which effector, or body part, is being used in an action (Bergen et al., 2010), the shape of an object described (Stanfield and Zwaan, 2001), and the axis along which motion occurs (Richardson et al., 2003), these findings suggest people use partially overlapping representations for processing information about physical action and space and linguistic content about action and space.

Functional imaging studies have demonstrated support for this conclusion through comparisons of brain regions involved in sensory perception (e.g., tactile, visual) and motor function with the brain regions involved in processing language whose meaning may be derived using these modalities (Just et al., 2004; Boulenger et al., 2009; Moody and Gennari, 2009; Saygin et al., 2010; Willems et al., 2010). In the domain of motor output, Moody and Gennari (2009) found that a region in premotor cortex was sensitive to the degree of real-world effort required for the action described by a verb in a particular context (e.g., pushing a piano requires more effort than pushing a chair). Interestingly, the anterior inferior frontal gyrus, a region thought to be involved in semantic processing more generally (Demb et al., 1995; Kuperberg et al., 2008) (but not in motor processing, specifically), was also sensitive to the degree of effort. Furthermore, action words read on their own (e.g., kick, lick, etc.) have been shown to preferentially activate motor regions corresponding to the particular effector (Hauk et al., 2004). Using transcranial magnetic stimulation (TMS) to target specific areas of the motor strip, Pulvermüller et al. (2005) also observed selective interference for effector-specific regions in the motor strip for words related to those effectors. These findings suggest a role for the motor system in more general processing of linguistic content about action.

As for perceptual systems, Just et al. (2004) showed that, compared to low imageability sentences, highly imageable language (e.g., sentences like The number eight when rotated 90 degrees looks like a pair of spectacles) modulated activity in the intraparietal sulcus, a brain region thought to play a role in visual attention (Wojciuluk and Kanwisher, 1999) and visual working memory (Todd and Marois, 2004). Higher visual areas such as V5/MT+ have also been implicated in processing language about visual motion (Saygin et al., 2010), though others have found this region either to be unaffected by processing high-motion verbs compared to low-motion (Bedny et al., 2008) or implicated only in a minority of subjects for motion compared to static verbs (Humphreys et al., 2013).

This work converges to suggest that motor production and visual perception of motion are candidates for neurocognitive processes which may contribute to comprehending language about motion. It is now well-established that visually processing others' actions relies on neural mechanisms overlapping with those used for language processing (Rizzolatti et al., 2001; Arbib, 2005). In the present study, we focused in particular on biological motion, which refers to the characteristic movement patterns of animate entities as well as specific stimuli used in vision science to study its perception (see below; Johannson, 1973; Blake and Shiffrar, 2007). Producing and understanding biological motion are important functions for humans, and humans are sensitive to perceiving biological motion even when cues are relatively minimal, as with the point-light displays used in vision science (Johannson, 1973), which are animations showing only points placed over key joints of a moving person. Humans exhibit robust perception of biological motion even in degraded conditions (see Blake and Shiffrar, 2007, for a review).

Studies of biological motion perception using point-light walkers have most consistently implicated the posterior superior temporal sulcus (pSTS) as a key region (Grossman et al., 2000, 2005; Vaina et al., 2001; Beauchamp et al., 2003; Pelphrey et al., 2003; Puce and Perrett, 2003; Saygin, 2007; Vangeneugden et al., 2011; van Kemenade et al., 2012; Gilaie-Dotan et al., 2013). In addition, Kemmerer et al. (2008) found that the pSTS was specifically recruited more during silent reading of biological motion verbs similar to run, e.g., jog, walk, compared to other types of action verbs, implicating involvement of this region in both perception of visual biological motion and comprehension of language about such motion. Studies have also shown involvement of other regions in processing biological motion including parietal cortex, body and motion-sensitive visual areas in lateral temporal cortex (EBA, MT+), other areas in temporal and occipital cortex, and the cerebellum (Vaina et al., 2001; Grossman and Blake, 2002; Servos et al., 2002; Saygin et al., 2004b; Nelissen et al., 2005; Jastorff et al., 2010; Sokolov et al., 2012; Vangeneugden et al., 2014).

Importantly, regions that overlap with classical language areas in inferior frontal/ventral premotor cortex (PMC) have been linked to biological motion processing (Saygin et al., 2004b; Saygin, 2007; Pavlova, 2012; van Kemenade et al., 2012; Gilaie-Dotan et al., 2013). One interpretation of the role of frontal regions is that when people view point-light walkers, they recruit their own motor resources for performing the action, as suggested by proponents of embodied cognition and the “mirror neuron” system (Rizzolatti et al., 2001). That the premotor cortex, a brain region that supports the production of motor acts, is activated during perception of point-light walkers supports the notion that this process of motor simulation occurs even when the action is depicted via motion cues (Saygin et al., 2004b). The relationship between motor processing and biological motion perception is not purely correlational: disruption of processing in these regions due to brain injury or virtual lesions induced by TMS leads to deficits in biological motion perception (Saygin, 2007; van Kemenade et al., 2012). Furthermore, activation in these areas can be modulated in those who are experts at performing actions they are viewing, as in the case of professional dancers (Calvo-Merino et al., 2005; Cross et al., 2006). In the general population, individual differences in biological motion are predicted by individual levels of motor imagery (Miller and Saygin, 2013). Given the overlap between frontal regions involved in processing of visual biological motion on the one hand and language comprehension on the other, it is likely that language comprehension may benefit from recruitment of neurocognitive processes also involved in visual perception of motion.

There is therefore evidence that regions involved in both motor execution and visual biological motion perception can be recruited in understanding the semantics of literal language. Another active area of inquiry is the processing of metaphorical meaning. The range of linguistic use and experience extends far beyond the most literal uses of verbs like throwing and walking to uses in figurative and metaphorical contexts. Conceptual metaphor theory (Lakoff, 1993) proposes that metaphors are understood through a mapping from more concrete source domains (for instance, space) to more abstract target domains (for instance, time, as in, Time is flying by). This theory leads to predictions that the cognitive and neural representation of concrete verbs will be activated when they are used metaphorically due to the mapping from the source to target domains. For instance, in the sentence, The movie was racing to its end, the verb racing might activate brain regions involved in motor execution of running or racing.

Studies directly comparing literal and metaphorical language to investigate whether brain regions and cognitive processes involved in sensory and motor processing are recruited equally for both types of language have found mixed results. Bergen et al. (2007) observed null effects when investigating metaphorical language about space in their spatial interference paradigm. Unlike literal language, where interference effects were observed, metaphorical language related to the spatial concepts “up” (The numbers rocketed) and “down” (The quantity fell) did not lead to interference when participants made decisions about objects located in the upper or lower halves of a computer screen, respectively. These findings suggest no (or lesser) overlap for spatial representations and metaphorical language about space (compared to literal language about space).

However, other studies have provided evidence that non-literal uses of language about space and motion do recruit more general perceptuo-motor representations. For instance, Matlock et al. have argued that when participants read sentences involving fictive motion describing static events using motion verbs, they mentally simulate motion despite no implication of a physical change (Matlock, 2004; Richardson and Matlock, 2007). For instance, Matlock (2004) had participants read stories ending in a sentence containing a fictive motion verb (e.g., The road runs through the valley) and make judgments about whether the sentence made sense given the context. For fictive motion sentences (but not for literal sentences in control experiments, which did not contain fictive motion), the time to make the decision was dependent on properties of the sentence including the speed of travel, the distance traveled, and the ease or difficulty of terrain. These findings minimally suggest that even for language that doesn't imply true motion, individuals access motion-like properties when processing fictive motion verbs.

In a study of metaphorical uses of motion verbs, Wilson and Gibbs (2007) looked at how quickly phrases were read following real or imagined movements made by participants. Across two experiments, participants memorized a set of actions to be performed (Experiment 1) or imagined (Experiment 2) when they viewed particular symbols (e.g., the symbol “and” was paired with the action push). Then, they performed a task in which they viewed a symbol, either performed or imagined the action, and then read metaphorical language either related (e.g., push the argument) or not (e.g., stamp out a fear) to the action. For both performed and imagined actions, participants were faster to read phrases (as measured by the response time of a button press after reading the phrase) when the previous action was congruent with the verb. Wilson and Gibbs interpreted these findings as evidence that processing of metaphorical uses of action verbs relies on representations shared with executing their literal meanings physically. However, if individuals access lexical representations of verbs associated with performed or imagined actions (e.g., activating the word push while performing the action of pushing), this alone could be sufficient to prime reading of the phrase push the argument even if participants do not activate such representations during normal metaphorical language comprehension. An additional limitation of this study is that it provided no literal comparison (e.g., reading phrases liked push the cart, or even reading bare verbs like push). Such comparisons would be informative as to the extent to which such concepts (like push), when used metaphorically, recruit representations overlapping with those used in motor executions.

In the neuroimaging literature, evidence that metaphorical language recruits perceptuo-motor representations is also mixed. Some studies have found no evidence that processing metaphorical language about particular body parts, for instance, recruits brain regions involved in moving those body parts (Aziz-Zadeh et al., 2006; Raposo et al., 2009). One study using word-by-word reading of language (rather than whole-sentence reading) observed a relationship between both literal and idiomatic sentences involving different parts of the body and the corresponding somatotopic regions of the motor strip (Boulenger et al., 2009). For instance, sentences like John grasped the object/idea elicited stronger activity in the finger areas of motor strip while sentences like Pablo kicked the ball/habit elicited stronger activity in the foot areas of motor strip. However, this study involved a limited number of stimuli in each condition with many repetitions across the experiment, which limits the conclusions that can be drawn about typical sentence comprehension.

Other imaging studies have investigated fictive motion sentences, with mixed results. (such as A crack was running along the wall or The pipe goes into the house). One study found no difference in activations in visual motion perception regions for language describing fictive motion and actual motion (Wallentin et al., 2005). Saygin et al. (2010) individually located motion-sensitive areas as well as face-sensitive areas in each participant and compared brain activity in real motion, fictive motion, and static sentences which were presented as audiovisual movies of a person speaking the sentences. They observed a gradient pattern: actual motion sentences elicited the greatest amount of activity in visual motion perception areas, followed by fictive motion sentences and finally static sentences. This pattern of activity was not observed in face-sensitive areas, showing that the effect was indeed related to motion semantics. In another study, literal motion sentences also modulated activity in motion-sensitive areas for American Sign Language, suggesting that the concurrent recruitment of motion processing mechanisms during language processing does not abolish the effect (McCullough et al., 2012). These findings suggest that both literal and figurative language about motion recruits brain regions involved in visual motion perception, though to a lesser extent by the latter than the former.

Bergen (2012) suggests that mixed results in studies investigating recruitment of perceptuo-motor representations during metaphorical language comprehension may be due to the timecourse of processing. In many studies investigating metaphor (e.g., Aziz-Zadeh et al., 2006; Raposo et al., 2009), whole sentences are presented concurrently to the participant, a procedure which may not maintain the temporal precision necessary to observe effects. In other studies using either shorter phrases or word-by-word presentation of metaphorical language, effects have been observed both behaviorally (Wilson and Gibbs, 2007) and in neuroimaging data (Boulenger et al., 2009). Consider the following metaphorical sentence, an example from our materials: The story was ambling toward its conclusion. In natural spoken language, at the point of processing the word ambling, the listener may already have enough information (from having heard, first, The story) to know that the literal use of ambling is inappropriate; stories are abstract and have no legs. However, there are certain similarities that might be mapped out between stories, which cannot amble, and people, who can. A story takes place on a timeline, and people perceive a timeline through which life moves forward. There are therefore systematic relationships between the word ambling used metaphorically and ambling used literally. However, in the case of this metaphorical sentence, it is possible that the full metaphorical meaning might not be understood until the end of the sentence (after having heard toward its conclusion). That is to say, incrementally comprehending the meaning of such a metaphor might operate rather differently than incrementally comprehending the meaning of a similar literal sentence (e.g., The teacher was ambling toward the school). Further, while metaphorical language can recruit brain regions thought to underlie perceptuo-motor representations relevant for the literal use of the language, evidence suggests that these representations may not be as strongly activated for metaphorical language as for literal language (Saygin et al., 2010).

Here, we examined the extent to which processing visual biological motion affected the processing of motion verbs used in both metaphorical and literal contexts. We used short videos of point-light walkers (Johannson, 1973), which display representations of human biological motion, as primes. To determine the effect that recently viewing physical walking motion would have on processing closely-matching verbs (such as ambling, walking) compared to more distantly-matching verbs (such as leaping, catapulting), we also used a control motion condition with inverted, scrambled versions of the point-light walkers. A novel contribution of our approach is that the study fully crosses literal and metaphorical language (using identical verbs) with prime type (presence or absence of an action prime) and match-type of the verb use. Following other behavioral and neuroimaging research, we expected to see facilitation following the point-light walker during self-paced reading for literal sentences containing closely-matching verbs compared to those containing distantly-matching verbs. As for our metaphorical sentences, which used the same verbs as the literal sentences but in different contexts, we predicted that if processing visual biological motion is less involved (on average) when reading metaphorical language, we would observe a smaller difference in (or absence of) facilitation between closely-matching and distantly-matching verbs. Such findings would also indicate that processing metaphorical verbs might rely upon a less precise representation of the motion described by the verb.

In Experiment 2, we sought to replicate and extend the finding from Experiment 1 that the processing of literal and metaphorical language about biological motion was affected by visual processing of biological motion in different ways. We also attempted to tease apart potential effects of visual form and visual motion on language processing. To this end, we randomly assigned half of our participants to view primes that were videos of point light displays (identical to those used in Experiment 1), and the other half saw primes that were static images created from similar displays of either randomly displayed dots or point-light walkers. We predicted that if the visual image of the form of a walker alone is enough to imply motion, then we should see nearly identical processing of language following still images compared to motion videos. If, however, visual form is not sufficient to activate neurocognitive representations of motion that may be accessed in language comprehension, then we may observe no priming effects for the still images (or smaller priming effects). We were also interested in the extent to which the still images might have a different effect on metaphorical and literal language, compared to the motion video clips. For instance, more-specific representations of biological motion might be accessed when processing literal biological motion language (such as The teacher was ambling toward the school.), but less-specific representations of biological motion might be accessed when processing metaphorical biological motion language (like The story was ambling toward its conclusion.). If this is the case, then we might see priming for only the metaphorical sentences following static primes, but not for literal sentences.

In summary, we observed different patterns of reading times for metaphorical compared to literal sentences following biological motion video and (to some extent) still image primes. Across two experiments, for literal sentences, we observed a pattern that may roughly be connected with interference for sentences that contained verbs closely matching the sensorimotor content of the primes. However, in Experiment 1, for metaphorical sentences, we observed a pattern that suggested interference for sentences containing distantly-matching verbs. As for still images, we observed a similar pattern, except that effects were not observed at the verb region of sentences, but rather at a later prepositional phrase at the end of the sentence.

What type of mechanism could cause Close-Match verbs to be processed more slowly in literal sentences but more quickly in the metaphorical sentences? To the extent that an interference-type pattern emerged for the Close-Match verbs in the Literal condition following videos of point-light walkers, this pattern may have been due to difficulty in accessing a precise representation. For instance, if a participant had just read a Literal sentence with the phrase was ambling, she may have attempted to access a recently-activated representation of walking (recently accessed due to the viewing of a video prime of an upright point-light walker). However, if the recently-accessed representation did not constitute a close enough fit with the desired element in memory (e.g., a representation of ambling), the participant may have sensed an error due to a slight mismatch between the recently-accessed walking and the attempted access to ambling.

Relatedly, semantic priming paradigms have demonstrated that for coordinates, that is, categorically related words or pictures which might be used in many similar situations, participants often exhibit interference effects rather than facilitation in picture-naming tasks involving word primes (Alario et al., 2000; Sailor et al., 2009). Semantic priming studies have primarily been conducted using noun coordinates describing objects and animate beings, though one recent study in by Bergen et al. (2010) used pictures and words in a verification task to investigate actions and verbs. Participants were slower to reject mismatching picture-word pairs when the effector typically used to perform the action was the same across the picture and the word (e.g., a picture of someone running and the word kick). Here, the presence of interference for similar types of actions also suggests that people activate overlapping representations in visual and verbal modalities. In our study, the visual prime of a walking action and the verb region of the sentences similarly provide an analog to noun coordinate studies using action/verb coordinates. It is possible that for our literal sentences, residual activation of a walking action led to interference for processing the verb when it closely matched the walking action. For the Distant-Match verbs, it could be that participants were able to better use previously activated sensorimotor features from the walking action, with lack of precise match allowing for facilitation in a way that the closer-matching verbs did not achieve. This might be possible if it was easier to distinguish between the walking action and, e.g., verbs like catapulting, but both share some overall semantic features such as motion. This pattern is roughly analogous to findings from the semantic priming literature showing that semantic associates lead to facilitation under circumstances when semantic coordinates do not (Alario et al., 2000; Sailor et al., 2009). This is not to say that our videos (and static images) of a walking action and Distant-Match verbs like catapulting are in fact semantic associates, but a relationship remains between the two which is substantially different from the relationship between the walking action and our Close-Match verbs.

It is important to note that coordinate interference effects in picture-naming tasks are typically restricted to short priming latencies (Alario et al., 2000; Sailor et al., 2009). In our studies, latency for the presentation of the critical verb following the visual prime was variable, given that participants read each phrase at a self-paced rate, but on average, latencies were much longer (including the time between the prime and beginning to read the sentence as well as the time it took to read the first phrase of the sentence). To our knowledge, no other study has examined the timing dynamics of such priming effects of verbs in sentences.

It is difficult to know precisely why such differences for the Static group emerged later in the sentence. One possibility is that activation of sensorimotor semantic content following images may be slower-acting compared to videos. A related possibility is that videos increase the strength of activation levels (in a spreading-activation-type semantic network, e.g., Anderson, 1983). As for the Static primes, the information might not have been activated strongly enough to create such interference/facilitation effects until further down the line, when the content of the sentence had been processed more fully, possibly during so-called “sentence wrap-up” effects (Just and Carpenter, 1980; Rayner et al., 2000).

As for the Metaphorical sentences, it is unclear why the findings from Experiment 1 did not replicate in the Motion group in Experiment 2. It is possible that Experiment 2 was under-powered and that the numerical difference would be reliable in a larger group. To the extent that the findings from Experiment 1 are replicable, however, it appears that metaphorical language containing biological motion verbs may rely on less-specific sensorimotor representations compared to literal language, as indicated by the fact that interference-type effects were observed for the verbs which distantly, rather than closely, matched the content of the video primes. For the still images (Experiment 2), effects were again observed later in the sentence (as was the case for the Literal sentences), and may therefore reflect a similar phenomenon of either slower-acting or weaker activation of sensorimotor semantic content following images compared to videos.

Though our experimental sentences were matched for many lexical properties, the first noun of the metaphorical sentences was found to be more highly imageable for Close-Match conditions compared to Distant-Match conditions. Imageability is known to be highly correlated with concreteness, both of which are known to affect reading times (for critical word 1 in the experimental and filler items from the present study, imageability and concreteness were highly correlated, r = 88.55, p < 0.001). In general, high concreteness and imageability are thought to be associated with shorter reading times compared to lower concreteness and imageability (Holmes and Langford, 1976; Juhasz and Rayner, 2003), though this may be modulated by individual differences in a tendency to use imagery (Denis, 1982). However, our results indicated that for metaphorical sentences, differences in reading times at the verb region (just subsequent to processing the subject noun region) went in the opposite direction, with the more highly imageable Distant-Match condition leading to longer reading times during the verb region compared to the less highly imageable Close-Match condition. We argue that this pattern indicates a form of facilitation for more closely-matching verbs, which did not themselves differ in mean imageability across the Close- and Distant-match conditions. Given that the differences indicated by the t-test would bias our results in the opposite direction, we do not see this differences as terribly worrisome for our interpretation. However, future studies would do well to more carefully match this property across items.

The possibility that metaphors may be associated with the processing of less precise semantic content—that is, that they are associated with a broad distribution of content from semantic memory compared to literal language—is consistent with popular theories about right-hemisphere language processing. First, data from patients with right-hemisphere compared to left-hemisphere lesions (Winner and Gardner, 1977) and studies of healthy participants using methods from cognitive neuroscience (Mashal and Faust, 2008; Pobric et al., 2008) suggest preferential processing of metaphorical language by the right hemisphere, though not all experimental data support this interpretation (e.g., Coulson and Van Petten, 2007). Second, the right hemisphere may operate over less fine-grained linguistic representations than the left hemisphere. This “coarse coding” hypothesis (Beeman et al., 1994) suggests that there are hemispheric differences in specificity of coding of linguistic information, with the left hemisphere possibly honing in on specific words/concepts while the right hemisphere may activate a broader array of words and/or conceptual content. Our findings are consistent with the notion that broader arrays of semantic content may be activated during the processing of metaphorical language compared to literal language.

Mashal et al. (2007) suggest that the right hemisphere may not necessarily be specialized for metaphorical uses of language, per se, but rather for non-familiar language (similar to the “Graded Salience Hypothesis”; Giora, 1997). In an fMRI study, they observed an increased activation in the right hemisphere for novel metaphors (such as pearl tears), but not for conventional metaphors (such as bright student). Relatedly, the “career of metaphor” hypothesis (Bowdle and Gentner, 2005) proposes that as metaphors age, becoming more and more frequent in production, they become more crystallized so that the original, compositional meaning of their components is lost, and the full meaning of the metaphor is all that is retained. Under this hypothesis, proposals such as Lakoff's (1993) theory of conceptual metaphor are only relevant for new metaphors. That is, novel metaphors are more likely to be interpreted as mappings from a more concrete source domain to the more abstract target domain whereas older metaphors are more fixed in meaning (in the target domain). Recently, an fMRI study by Desai et al. (2011) found imaging evidence to support this hypothesis. They investigated sensorimotor metaphors which were rated as more or less familiar by an independent set of participants. An inverse correlation between familiarity of the metaphor and activation of primary motor areas was observed, such that more familiar metaphors activated these areas to a lesser extent. The authors took these findings as evidence for the (abstract) target of metaphors being “… understood in terms of the base domain through motoric simulations, which gradually become less detailed while still maintaining their roots in the base domain” (p. 10).

The metaphors used in the present studies are likely to be relatively new metaphors, by such definitions, which means that according to proposals like Bowdle and Gentner's (2005) “career of metaphor” theory and Mashal et al. (2007) hypothesis regarding the novelty of metaphors, these are the types of metaphors that are likely to engage the recruitment of sensorimotor representations in their processing. According to these theories, in doing so, they may also be likely to engage a different pattern of brain regions from those engaged when processing literal sentences. Our findings are consistent with a story wherein metaphorical language is processed in a different way from literal language, but still may recruit sensorimotor representations overlapping with the processing of visual biological motion and possibly implied motion (as suggested by the findings from the Static group in Experiment 2).