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Many studies use manual action verbs to test whether people use neural systems for controlling manual actions to understand language about those actions. Yet, few of these studies empirically establish how people use their hands to perform the actions described by those verbs, relying instead on explicit self-report measures. Here, participants pantomimed the manual actions described by a large set of Dutch (N = 251) and English (N = 250) verbs, allowing us to approximate the extent to which people use each of their hands to perform these actions. After the pantomime task, participants also provided explicit ratings of each of these actions. The results from the pantomime task showed that most manual actions cannot be described accurately as either "unimanual" or "bimanual." With a few exceptions, unimanual action verbs do not describe actions that are performed with only one hand, and bimanual verbs do not describe actions that are performed by using both hands equally. Instead, individual actions vary continuously in the extent to which people use their non-dominant hand to perform them, and in the extent to which people consistently prefer one hand or the other to perform them. Finally, by comparing participants' implicit behavior to their explicit ratings, we found that participants' self-report showed only limited correspondence with their observed motor behavior. We provide all of our measures in both raw and summary format, offering researchers a precision tool for constructing stimulus sets for experiments on embodied cognition.

Processing the meaning of action language correlates with somatotopic activity in premotor cortex (PMC). A previous neurostimulation study supported a causal contribution of PMC activity to action verb understanding, but the direction of the effect was unexpected: inhibiting PMC made participants respond faster to action verbs. Here we investigated the effects of PMC excitation and inhibition on action verb understanding using tDCS. Right-handed participants received tDCS stimulation with the anodal electrode (presumed to be excitatory) and cathodal electrode (presumed to be inhibitory) placed over left and right PMC, respectively, or with the reverse configuration. After completing the stimulation protocol, participants made lexical decisions on unimanual action verbs (e.g., throw) and abstract verbs (e.g., think). tDCS configuration selectively affected how accurately participants responded to unimanual action verbs. When the anode was positioned over left PMC we observed a relative impairment in performance for right-hand responses (i.e. the hand with which these participants typically perform unimanual actions). By contrast, when the cathode was positioned over left PMC we observed a relative improvement. tDCS configuration did not differentially affect responses to abstract verbs. These complementary effects of excitatory and inhibitory tDCS clarify the functional role of premotor hand areas in understanding action language.

Instrumental music and language are both syntactic systems, employing complex, hierarchically-structured sequences built using implicit structural norms. This organization allows listeners to understand the role of individual words or tones in the context of an unfolding sentence or melody. Previous studies suggest that the brain mechanisms of syntactic processing may be partly shared between music and language. However, functional neuroimaging evidence for anatomical overlap of brain activity involved in linguistic and musical syntactic processing has been lacking. In the present study we used functional magnetic resonance imaging (fMRI) in conjunction with an interference paradigm based on sung sentences. We show that the processing demands of musical syntax (harmony) and language syntax interact in Broca's area in the left inferior frontal gyrus (without leading to music and language main effects). A language main effect in Broca's area only emerged in the complex music harmony condition, suggesting that (with our stimuli and tasks) a language effect only becomes visible under conditions of increased demands on shared neural resources. In contrast to previous studies, our design allows us to rule out that the observed neural interaction is due to: (1) general attention mechanisms, as a psychoacoustic auditory anomaly behaved unlike the harmonic manipulation, (2) error processing, as the language and the music stimuli contained no structural errors. The current results thus suggest that two different cognitive domains-music and language-might draw on the same high level syntactic integration resources in Broca's area.

In Arabic, as in many languages, the future is "ahead" and the past is "behind." Yet in the research reported here, we showed that Arabic speakers tend to conceptualize the future as behind and the past as ahead of them, despite using spoken metaphors that suggest the opposite. We propose a new account of how space-time mappings become activated in individuals' minds and entrenched in their cultures, the temporal-focus hypothesis: People should conceptualize either the future or the past as in front of them to the extent that their culture (or subculture) is future oriented or past oriented. Results support the temporal-focus hypothesis, demonstrating that the space-time mappings in people's minds are conditioned by their cultural attitudes toward time, that they depend on attentional focus, and that they can vary independently of the space-time mappings enshrined in language., (© The Author(s) 2014.)

The QWERTY keyboard mediates communication for millions of language users. Here, we investigated whether differences in the way words are typed correspond to differences in their meanings. Some words are spelled with more letters on the right side of the keyboard and others with more letters on the left. In three experiments, we tested whether asymmetries in the way people interact with keys on the right and left of the keyboard influence their evaluations of the emotional valence of the words. We found the predicted relationship between emotional valence and QWERTY key position across three languages (English, Spanish, and Dutch). Words with more right-side letters were rated as more positive in valence, on average, than words with more left-side letters: the QWERTY effect. This effect was strongest in new words coined after QWERTY was invented and was also found in pseudowords. Although these data are correlational, the discovery of a similar pattern across languages, which was strongest in neologisms, suggests that the QWERTY keyboard is shaping the meanings of words as people filter language through their fingers. Widespread typing introduces a new mechanism by which semantic changes in language can arise.

Does language comprehension depend, in part, on neural systems for action? In previous studies, motor areas of the brain were activated when people read or listened to action verbs, but it remains unclear whether such activation is functionally relevant for comprehension. In the experiments reported here, we used off-line theta-burst transcranial magnetic stimulation to investigate whether a causal relationship exists between activity in premotor cortex and action-language understanding. Right-handed participants completed a lexical decision task, in which they read verbs describing manual actions typically performed with the dominant hand (e.g., "to throw," "to write") and verbs describing nonmanual actions (e.g., "to earn," "to wander"). Responses to manual-action verbs (but not to nonmanual-action verbs) were faster after stimulation of the hand area in left premotor cortex than after stimulation of the hand area in right premotor cortex. These results suggest that premotor cortex has a functional role in action-language understanding.

According to embodied theories of language, people understand a verb like throw, at least in part, by mentally simulating throwing. This implicit simulation is often assumed to be similar or identical to motor imagery. Here we used fMRI to test whether implicit simulations of actions during language understanding involve the same cortical motor regions as explicit motor imagery. Healthy participants were presented with verbs related to hand actions (e.g., to throw) and nonmanual actions (e.g., to kneel). They either read these verbs (lexical decision task) or actively imagined performing the actions named by the verbs (imagery task). Primary motor cortex showed effector-specific activation during imagery, but not during lexical decision. Parts of premotor cortex distinguished manual from nonmanual actions during both lexical decision and imagery, but there was no overlap or correlation between regions activated during the two tasks. These dissociations suggest that implicit simulation and explicit imagery cued by action verbs may involve different types of motor representations and that the construct of "mental simulation" should be distinguished from "mental imagery" in embodied theories of language.

Do neural systems for planning motor actions play a func-tional role in understanding action language? Across multi-ple neuroimaging studies, processing action verbs correlateswith somatotopic activity in premotor cortex (PMC). Yet, onlyone neurostimulation study supports a functional role for PMCin action verb understanding: paradoxically, inhibiting PMCmade people respond faster to action verbs. Here we investi-gated effects of PMC excitation and inhibition on action verbunderstanding using tDCS. Right-handers received excitatoryor inhibitory stimulation to left PMC hand areas, then madelexical decisions on unimanual action verbs and abstract verbs.tDCS polarity selectively affected how accurately participantsresponded to unimanual action verbs. Inhibitory stimulationto left PMC caused a relative improvement in performance forright-hand responses, whereas excitatory left PMC stimulationcaused a relative impairment. tDCS polarity did not differ-entially affect responses to abstract verbs. Premotor areas thatsubserve planning actions also support understanding languageabout these actions.