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In a preregistered experiment, we tested whether interfering with primary motor cortex (M1) activation can change how people construe meaning from language. Participants were presented with sentences describing motor actions and asked to choose between a concrete and an abstract interpretation of their meaning. Prior to this task, participants' M1 was disrupted using repetitive transcranial magnetic stimulation (rTMS). The results suggested strong evidence against the idea that M1-rTMS affects meaning construction. Additional analyses and experiments suggest that the absence of effect cannot be accounted for by failure to inhibit M1, lack of task validity, or lack of power to detect a small effect. These results do not support a causal role for primary motor cortex in building meaning from action language.

How does thinking differ across cultures? Previously, we reported that Chinese people tend to think more abstractly than Caucasian Americans, as indexed by their propensity to construe actions either abstractly or concretely (Singh et al., 2019). Here we provide further evidence for the cultural diversity of abstract thought: We report action construal data from Japan and South Korea, and compare them to our previous Chinese and American data. Chinese, Japanese, and South Korean patterns of action construal all differed significantly from one another. Whereas Chinese participants construed actions more abstractly than American participants, South Koreans did not differ from Americans, and Japanese participants construed actions less abstractly than Americans. The diversity of these East Asian data challenges the assumption that people from China, Japan, and South Korea have a unified “Eastern” cognitive style. Furthermore, these results challenge the longstanding generalization that Westerners think more abstractly than non-Westerners.

According to a large body of research, the left and right cerebral hemispheres are specialized for different frequencies, in vision and audition, but the cause of this specialization is unknown. Here, we tested whether hemispheric asymmetries in visual perception can be explained by asymmetries in people’s tendency to perform high- and low-frequency actions with their dominant and nondominant hands, respectively (the Action Asymmetry Hypothesis [AAH]). In a large, preregistered, online study, participants (N = 1008) judged low- and high-frequency shapes presented in the left and right visual hemifields. Overall, the typical hemispheric asymmetry for high vs. low visual frequencies, which we found in right handers, was significantly reduced in left handers. Hemispheric asymmetries for high-spatial-frequency stimuli were completely reversed between right and left handers. These results provide initial support for the AAH: Frequency asymmetries in perception may be explained by frequency asymmetries in action.

People are more likely to gesture when their speech is disfluent. Why? According to an influential answer to this question, people gesture when they are disfluent because gestures facilitate speech production (Krauss & Hadar, 1999). Here, we propose an alternative explanation: People may gesture when their speech is less fluent because gestures serve as a pragmatic signal by commenting on problems with speaking. If so, when the listener cannot see the speaker, the speaker’s pragmatic motivation to gesture more during disfluencies should disappear. As predicted, we showed that people were more likely to gesture when their speech is disfluent only when the listener can see their gestures, but not when the listener cannot see their gestures. These results suggest that people gesture more when speaking is difficult, not because gestures facilitate speech, but rather because gestures comment on speakers’ difficulty with presenting an utterance for the listener.

We investigated the influence of the COVID-19 pandemic on young people’s value temporal focus, religiosity, and time spatialization. Samples of young participants from eight cultures (Americans, Spaniards, Serbs, Bosniaks, Croats, Moroccans, Turks, and Chinese) collected before the pandemic (N = 497, mean age = 21.09) were matched with samples collected during the first confinement period (N = 497, mean age = 20.96). Our results in study 1 showed that during the pandemic, young adults were less religious, more future-focused, and placed the future in front to of them in a greater extent. In study 2, using the whole sample collected during the pandemic (N = 893, mean age = 21.94), we observed that the more affected the participants were by the pandemic, the greater their future focus, the lower their religiosity, and the greater their tendency to locate the future in front. These pattern of results held in most cultures.

Using space to think about time appears to be a human universal, but the specifics of people’s space-time mappings vary across individuals and groups. What determines how people spatialize time in their minds? Here we hypothesized that motor experience contributes to individuals’ space-time mappings, independent of linguistic and cultural factors. Many everyday motor actions require using the hands in a particular sequence (e.g., positioning a nail with the nondominant hand before swinging the hammer with the dominant hand), establishing a correlation between space (left hand, right hand) and time (earlier action, later action) that reverses with handedness. These action sequences reinforce Westerners’ typical left-to-right mental timeline for right-handers, but contradict this timeline for left-handers. Accordingly, we find that right-handers associate leftward space with earlier times and rightward space with later times more strongly than left-handers, for whom cultural and bodily experiences present contrasting relationships between space and time.

Are left handers more creative than right handers? In both popular belief and scientific literature, left-handedness is linked with higher creativity. Here, we evaluate whether left handers are better at divergent thinking, and whether left handers are overrepresented in creative professions, in a qualitative review supported by meta-analysis. We argue that plausible mechanisms for a creativity-handedness link can be found within influential theories of the neural basis of creativity. However, our meta-analysis does not find evidence that left or mixed handers are better at divergent thinking; in fact, right handers score slightly higher on the Alternate Uses Test. Additionally, we conclude that while left and mixed handers may be overrepresented in Art and Music, they are underrepresented in creative professions in general. We find that although both right and left handers tend to believe that left handers are more creative, this belief is not supported by the available empirical evidence.

According to a long-standing dogma, Westerners are more capable of thinking abstractly than East Asians. Here, we challenge this generalization by comparing US and Chinese adults in a paradigm case of abstract thinking: analogy. Chinese and American participants completed the most difficult set of Raven’s (2003) Standard Progressive Matrices (SPM), a widely used test of analogical reasoning. For each item, participants attempted to discern the analogical relationships between parts of an incomplete matrix to identify the correct way to complete it. Chinese participants produced significantly more correct answers on the SPM, indicating more successful analogical reasoning. We replicated this result with a second sample of Chinese participants. This cross-cultural difference remained significant when demographic factors were controlled. We predicted this difference, reasoning that East Asian’s sensitivity to context gives them an advantage over Westerners in various kinds of abstract thinking.

Why do people gesture when they speak? According to one influential proposal, the Lexical Retrieval Hypothesis (LRH), gestures facilitate speech production by helping people find the right spatial words. Do gestures also help speakers find the right words when they talk about abstract concepts that are spatialized metaphorically? If so, gesture prevention should increase disfluencies during speech about both literal and metaphorical space. We sought to conceptually replicate the finding that gesture prevention increases disfluencies in speech about literal space, which has been interpreted as evidence for the LRH, and to extend this pattern to speech about metaphorical space. Our large dataset provided no evidence that gestures facilitate speech production, even for speech about literal space. Upon reexamining past research, we conclude that there is, in fact, no reliable evidence that preventing gestures makes speech more disfluent. These findings challenge long-held beliefs about why people gesture when they speak.

People from Western and East Asian cultures exhibit systematic differences in perception, attention, and cognition. Why do people from these cultures think differently? According to an influential proposal, psychological differences between Westerners and East Asians reflect, and may derive from, differences between ancient Greek and ancient Chinese philosophies. Here, we critique this proposal in two ways. First, we argue that the way ancient Greek philosophy is represented in the cultural psychology literature is skewed, highlighting differences between ancient Greek and Chinese beliefs, and obscuring similarities. Second, we argue that no causal mechanism has been offered by which ancient philosophies could give rise to modern cross-cultural differences.

Information in speech appears in bursts. To optimize speech perception, the brain aligns these bursts of information with slow rhythms in neural excitability (

Is numerosity an abstraction that arises downstream of basic perceptual processing, or does the brain process numerosity like a primary perceptual feature such as color or motion? Here, we tested whether visual cortex computes number automatically, even when number is task-irrelevant and is being processed unconsciously. We recorded electroencephalography while subjects watched dotcloud stimuli that alternated in numerical content at 15 Hz, under one of three conditions: judging numerosity, judging convex hull, or making no judgments. Under all three conditions, we observed oscillatory activity at 15 Hz in early visual cortex. The strength of this signal depended on the numerical content of the stimuli in all three conditions and did not differ significantly across the conditions. Results show that number can be computed spontaneously by visual cortex, even when participants are attending to non-numerical information, consistent with the proposal that number is a primary perceptual attribute of visual stimuli.

What role does the motor system play in language understanding? Here we show that effector-specific motor interferencecan change how people interpret language about actions. An action like voting can be understood in terms of its concretedetails (writing marks on a ballot) or its abstract significance (influencing an election). If neural circuits for performingmotor actions enable people to mentally represent an actions concrete details, then occupying these circuits with a sec-ondary motor task should make the actions details harder to represent. Consistent with this hypothesis, in two experiments(N=180), tapping a complex rhythm with either the hands or the feet increased the proportion of abstract interpretations ofphrases describing actions with the same effector. Thus, meaningless motor activity causes qualitative changes in languagecomprehension: Performing different actions can lead to different understandings of the same words and phrases.

The Temporal Focus Hypothesis proposes that a person’s tendency to conceptualize either the past or the future as beinglocated in front of them depends on their temporal focus: the balance of attention paid to the past (tradition) and thefuture (progress). How general is the TFH and to what extent can cultures and subcultures be placed on a single linerelating time spatialization and temporal focus in spite of stark differences in language, religion, history, and economicdevelopment? Data from 10 Western and Middle Eastern (sub)cultural groups (N=1198) were used to derive a linearmodel relating aggregated temporal focus and proportion of future-in-front responses. This model then successfully fittednine independently collected (sub)cultural groups in China and Vietnam (N=841). A logistic mixed model computedover the whole dataset (N=2039) showed that the group-level relation arose at the individual level and allowed precisequantification of its influence. Temporal focus shapes how people around the world think of time in spatial terms.

From early in life, people implicitly associate time, number,and other abstract conceptual domains with space. Accord-ing to the Generalized Magnitude System proposal, these men-tal mappings reflect a common neural system for represent-ing various magnitudes, and share a common spatial organiza-tion. In a test of this proposal, here we measured mappings ofsize, time, and number in the Tsimane’, an indigenous Ama-zonian group with few of the cultural practices (like readingand math) that spatialize size, time, and number in the expe-rience of industrialized adults. On three spatial axes, the Tsi-mane’ systematically arranged imagistic stimuli according totheir magnitudes, but they showed no directional preferencesoverall and individuals often mapped different domains in op-posite directions. The results are inconsistent with predictionsof the Generalized Magnitude System proposal but can be ex-plained by Hierarchical Mental Metaphor Theory, accordingto which mental mappings initially reflect a set of correlationsobservable in the natural world.

Is the human representation of time symmetrical or asymmetrical toward the past and the future? Some studies suggestthat we perceive the future as being closer, more attended and more valued than the past (indicating a future asymmetry).By contrast, asymmetries toward the past have been found in past-focused cultures. Yet, available evidence is still limitedand mixed. In the present work we searched for asymmetry in several temporal tasks (temporal distance, time discounting,temporal depth, and self-continuity) in a set of cultures that vary widely in their temporal focus (American, Spanish,Turkish, Chinese, Moroccan, Serbian, Bosniak and Croatian; total N=1075). The results supported an overall asymmetrytoward the future in all tasks, although it failed to be significant in most cultures when considered on their own. However,only self-continuity showed variations that can be explained by the contrast between past-focused versus future-focusedcultures.

Why do people use space to think about time more than vice versa? On one account, a spacetime asymmetry in languagegives rise to the spacetime asymmetry in thought. If so, children should learn that polysemous words like long and shorthave primarily spatial meanings on the basis of language statistics. Yet usage statistics from which children could inferthe primacy of space are not obviously available in adult-to-child speech: Instead, caregivers use long and short moreoften in temporal senses than spatial senses (Casasanto & Ksa, 2019). Here we corroborate this result using word2vec, avector space model that reflects the co-occurrence structure of words. We show that the spacetime asymmetry is also notavailable in this semantic space: more words surrounding long and short are temporal than spatial. Rather than emergingfrom language, the spacetime asymmetry may reflect perceptual or conceptual asymmetries that precede the acquisition ofspatio-temporal language.

People implicitly map numbers onto space, but what aspect of numbers do people spatialize? When cardinality (i.e. mag-nitude; 5 objects) is pitted against ordinality (i.e., sequential position; the 5th object), people show an implicit ordinalitymapping, at least in lateral space. We hypothesized that if people spatialize numerical magnitude at all, they should do soon the vertical axis, according to the way they talk about numbers (i.e. low, high). Participants memorized sequences ofrandomized numbers (e.g. 85913) and then classified them (as small or large) using two response keys, oriented either lat-erally or vertically. Participants showed reliable ordinality mappings on both axes; they were faster to press the left/upperkey for numbers earlier in the memorized sequence and the right/bottom key for later numbers, regardless of numbersmagnitudes. People map exact numbers onto both lateral and vertical space according to their ordinality.

When people understand language about their own actions they activate premotor regions they use to perform these actions.Do people understand language about other peoples actions by imagining how they perform these actions themselves, orhow they perceive others performing them? Here, we recorded BOLD fMRI while left- and right-handers read about andthen imagined their own unimanual actions (e.g. you write) or others actions (e.g. she writes). When imagining theirown manual actions, participants preferentially activated PMC circuits controlling their dominant hand. By contrast, whenimagining others actions, participants PMC activity reflected both how they perform actions themselves and how theytypically see actions performed by right-handers (about 90% of people they see). Language-induced motor imagery forour own actions reflects how we use our own bodies, whereas imagery for others actions also reflects how others use theirbodies, even if their bodies differ from our own.

Why do people use space to talk about time, and to think about time, more than vice versa? On one proposal, this space-time asymmetry arises from the greater perceptual availability of space. Alternatively, a space-time asymmetry in languagecould give rise to the space-time asymmetry in thought during early language acquisition. If this language-first view iscorrect, then parents should use space-time words (e.g., long) more often in their spatial senses than in their temporalsenses, imparting to children the primacy of the spatial senses. More generally, childrens space-time word use shouldreflect the statistics of parental input. Results of a corpus analysis contradict both predictions: English speaking adultsused polysemous words more often in their temporal senses than in their spatial senses, whereas young children showedthe opposite pattern, in the same conversations. Asymmetries between space and time appear to precede and guide theacquisition of spatio-temporal language.

How do humans compute approximate number? According to one influential theory, approximate number representationsarise in the intraparietal sulcus and are amodal (independent of any sensory modality). Alternatively, approximate numbermay be computed initially within sensory systems. We tested for approximate number representations in the visual systemusing steady state visual evoked potentials (SSVEPs). We recorded EEG from human subjects while they viewed dotcloudspresented at 30 Hz. Alternating the dotcloud numerosity at 15 Hz evoked a 15 Hz SSVEP detectable over the occipital lobe(Oz). The SSVEP amplitude increased as the numerical difference between dotclouds increased, indicating that subjectsvisual systems were differentiating dotclouds on the basis of their numerical ratios. Critically, subjects were unable toconsciously discriminate dotcloud numerosity, indicating the rapid presentation disrupted reentrant feedback to visualcortex. Approximate number appears to be computed within the visual system, independently of higher-order areas suchas the intraparietal sulcus.

Do some cultures think more abstractly than others? According to tests of formal logic and rule-based reasoning, Western-ers tend to think more abstractly than East Asians. Yet, rule-based reasoning is only one type of abstract thinking. Moregenerally, thinking abstractly involves discerning relationships and seeing the big picture. Here we argue that previous testsof attention, perception, and memory can be interpreted as showing that East Asians tend to think more abstractly thanWesterners. To test this hypothesis directly we gave a validated measure of abstract thinking (Vallacher & Wegner, 1989)to Chinese and US individuals. Participants chose either abstract or concrete definitions of events. Across six indepen-dent national samples (total N=1,798), Chinese participants tended to construe events more abstractly, and US participantsmore concretely. Within China, more independent (Western-like) groups chose more concrete definitions. Together, theseresults challenge the generalization that Westerners have a greater propensity for abstract thought.

People use space to conceptualize abstract domains like timeand number. This tendency may be a cognitive universal, butthe specifics of people’s implicit space-time and space-numberassociations vary across cultures. How does culture shape ourabstract concepts? In Western cultures, both time and numbersare arranged in people’s minds along an imaginary horizontalline, from left to right, but in other cultures the directions of themental timeline (MTL) and mental number line (MNL) arereversed. The directions of both the MTL and MNL have longbeen assumed to depend on the direction in which people readand write text. Here we argue that this assumption is false, andshow that the MTL and MNL are shaped by different aspectsof cultural experience. In a training experiment, participantsspatialized time and numbers in opposite directions across theirfingers. Training changed the MTL and MNL in oppositedirections, as predicted by a general principle called theCORrelations in Experience (CORE) principle: peoplespatialize abstract conceptual domains in their minds accordingto the ways these domains are spatialized in their experience.

After viewing Black males faces, US participants are typically faster to categorize weapons and slower to categorize tools than afterviewing White male faces, revealing the activation of implicit stereotypes linking Black males with violent crime. Here we testedwhether hearing Black male voices speaking in African American Vernacular English (AAVE) activates these same threat-relatedstereotypes. In a national US sample, participants were faster to categorize weapons compared to tools after hearing race-neutralnames spoken in AAVE than after hearing them spoken in Standard American English (SAE). Like Black faces, Black voices canactivate violent stereotypes, affecting visual discrimination of objects.

Sports are a microcosm of society. A nations sports reflect its peoples values, and contribute to their social identity. Herewe investigated whether countries previously identified as individualistic versus collectivistic tend to excel in individualsports versus team sports, respectively. Individual sports like golf require athletes to focus on personal goals, whereasteam sports like hockey require players to cooperate and to focus on collective goals. We analyzed the rate of Olympicmedals won in individual versus team sports by 11 countries: 5 Western countries identified previously by sociologicaland psychological research as individualistic, and 6 East Asian or Eastern European countries identified as collectivistic.Paradoxically, results showed that individualistic countries won a greater proportion of medals in team sports, whereascollectivistic countries won more medals in individual sports. Findings support the view that cultural mindsets and valueorientations are domain-specific, not monolithic.

Spontaneous gestures suggest that English speakers tend to conceptualize time on the lateral (left-right) axis, even thoughthey use sagittal (front-back) space-time metaphors in language. Here we tested a skeptical explanation for this counterin-tuitive finding: Perhaps participants in previous gesture studies were biased to spatialize time laterally because the stimuliwere presented in left-to-right text? We randomly assigned English speakers to read stories about the past and future,or to listen to the same stories, and then to retell the stories to their partners. Regardless of the presentation modality,participants made systematic use of the lateral axis but not the sagittal axis, contrary to predictions based on linguisticmetaphors. English speakers preferential use of the lateral axis for time cannot be explained by exposure to written textin the experimental setting, but may result from long-term exposure to English orthography, among other cultural artifactsand practices that spatialize time laterally.

People implicitly associate different emotions with differentlocations in left-right space. Which dimensions of emotion dothey spatialize? Across many studies people spatializeemotional valence, mapping positive emotions onto theirdominant side of space and negative emotions onto their non-dominant side. Yet, other results suggest a contradictorymapping of emotional intensity (a.k.a., emotional magnitude),according to which people associate more intense emotionswith the right and less intense emotions with the left, regardlessof valence. To resolve this apparent contradiction, we firsttested whether people implicitly spatialize whicheverdimension of emotion they attend to. Results showed thepredicted valence mapping, but no intensity mapping. We thentested an alternative explanation of findings previouslyinterpreted as showing an intensity mapping; these data mayreflect a left-right mapping of spatial magnitude, not emotion.People implicitly spatialize emotional valence, but there is noclear evidence for an implicit lateral mapping of emotionalintensity.

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.

People conceptualize both time and numbers as unfoldingalong a horizontal line, either from left to right or from rightto left. The direction of both the mental timeline (MTL) andthe mental number line (MNL) are widely assumed to dependon the direction of reading and writing within a culture.Although experimental evidence supports this assumptionregarding the MTL, there is no clear evidence that readingdirection determines the direction of the MNL. Here wetested effects of reading experience on the direction of boththe MTL and MNL. Participants read English text eithernormally (from left to right) or mirror-reversed (from right toleft). After normal reading, participants showed the space-time associations and space-number associations typical ofWesterners. After mirror reading, participants’ space-timeassociations were significantly reduced but their space-number associations were unchanged. These results suggestthat the MTL and MNL have different experiential bases.Whereas the MTL can be shaped by reading experience, theMNL is shaped by other culture-specific practices throughwhich people experience numbers arrayed in left-right space.

People implicitly associate different emotions with different locations in left-right space. Which aspects of emotion do they spatialize, and why? Across many studies people spatialize emotional valence, mapping positive emotions onto their dominant side of space and negative emotions onto their non-dominant side, consistent with theories of metaphorical mental representation. Yet other results suggest a conflicting mapping of emotional intensity (a.k.a., emotional magnitude), according to which people associate more intense emotions with the right and less intense emotions with the left -- regardless of their valence; this pattern has been interpreted as support for a domain-general system for representing magnitudes. To resolve the apparent contradiction between these mappings, we first tested whether people implicitly map either valence or intensity onto left-right space, depending on which dimension of emotion they attend to (Experiments 1a, b). When asked to judge emotional valence, participants showed the predicted valence mapping. However, when asked to judge emotional intensity, participants showed no systematic intensity mapping. We then tested an alternative explanation of findings previously interpreted as evidence for an intensity mapping (Experiments 2a, b). These results suggest that previous findings may reflect a left-right mapping of spatial magnitude (i.e., the size of a salient feature of the stimuli) rather than emotion. People implicitly spatialize emotional valence, but, at present, there is no clear evidence for an implicit lateral mapping of emotional intensity. These findings support metaphor theory and challenge the proposal that mental magnitudes are represented by a domain-general metric that extends to the domain of emotion.