- Email: [email protected]
Language and the Construction of Time through Space
Alternatively, MNs themselves may play an instructive role in determining the pattern of locomotor output. Consistent with this idea, mutation in the limb MN determinant Foxp1 in mice leads to a loss of limb-specific output patterns, including the ability to reciprocally control extensor and flexor muscles [10]. Moreover, MNs of both vertebrates and invertebrates have been shown to retrogradely influence locomotor CPG output patterns [10,11].
programs among bilaterians, suggest Speakers of different languages that additional conserved features of think about time differently in motor networks await to be discovered. accordance with the spatial meta-
MN subtype identity also appears to play an instructive role in shaping connections within spinal premotor networks. Conversion of hypaxial MNs to a limb MN fate in mice, through mutation in the Hoxc9 gene, causes dramatic changes in the specificity of connections between MNs, spinal interneurons, and proprioceptive sensory neurons [12]. These changes in premotor input pattern appear to be a consequence in the altered position and dendritic architecture of the transformed MN populations. Although it is currently unknown whether these premotor connectivity alterations affect CPG function, their presence demonstrates that MNs play a critical role in shaping the connectivity and output patterns of locomotor circuits.
References 1. Jung, H. and Dasen, J.S. (2015) Evolution of patterning systems and circuit elements for locomotion. Dev. Cell 32, 408–422
Acknowledgments Work in the Dasen lab is supported by grants from the NIH (NINDS R01 NS062822, R21 NS099933). 1
Neuroscience Institute, Department of Neuroscience and Physiology, NYU School of Medicine, New York, NY 10016, USA *Correspondence: [email protected] (J.S. Dasen).
phors common in their languages. Furthermore, learning new spatial metaphors in language instills new non-linguistic representations of time, suggesting that language can play a causal role in constructing mental timelines.
https://doi.org/10.1016/j.tins.2018.07.013
2. Katz, P.S. (2016) Evolution of central pattern generators and rhythmic behaviours. Philos. Trans. R. Soc. Lond. B Biol. Sci. 371, 20150057 3. Arendt, D. (2018) Animal evolution: convergent nerve cords? Curr. Biol. 28, R225–R227 4. Kiehn, O. (2016) Decoding the organization of spinal circuits that control locomotion. Nat. Rev. Neurosci. 17, 224–238 5. Hagglund, M. et al. (2013) Optogenetic dissection reveals multiple rhythmogenic modules underlying locomotion. Proc. Natl. Acad. Sci. U. S. A. 110, 11589–11594 6. Marder, E. et al. (2015) Robust circuit rhythms in small circuits arise from variable circuit components and mechanisms. Curr. Opin. Neurobiol. 31, 156–163 7. Gao, S. et al. (2018) Excitatory motor neurons are local oscillators for backward locomotion. eLife 7, e29915 8. Sakurai, A. and Katz, P.S. (2017) Artificial synaptic rewiring demonstrates that distinct neural circuit configurations underlie homologous behaviors. Curr. Biol. 27, 1721–1734 9. Jung, H. et al. (2018) The ancient origins of neural substrates for land walking. Cell 172, 667–682 10. Dasen, J.S. (2017) Master or servant? Emerging roles for motor neuron subtypes in the construction and evolution of locomotor circuits. Curr. Opin. Neurobiol. 42, 25–32
Comparative studies have revealed both 11. Wright, T.M. and Calabrese, R.L. (2011) Contribution of motoneuron intrinsic properties to fictive motor pattern highly conserved and divergent mechageneration. J. Neurophysiol. 106, 538–553 nisms contributing to the development 12. Baek, M. et al. (2017) Columnar-intrinsic cues shape and functional properties of locomotor premotor input specificity in locomotor circuits. Cell Rep. 21, 867–877 rhythms. Whether early nervous systems contained circuit elements that are still used in modern species for locomotor control remains to be determined. Special Issue: Time in the Brain Recent methods for sequencing large numbers of neuronal types, in conjunc- Forum tion with comparisons across multiple species, should allow us to infer what common circuit elements contribute to the establishment of locomotor behaviors. The prevalence of locomotor CPGs in animals, as well as shared early Lera Boroditsky1,* patterning and MN specification
Language and the Construction of Time through Space
What is the role of language in constructing our representations of time? Time is a central topic of conversation in many languages. In English, the word ‘time’ is the most frequent noun, with other temporal words such as ‘day’ and ‘year’ also ranking in the top ten [1]. Do the ways we talk about time help construct the ways we think about it? In English, talk about time strongly overlaps with talk about space, with many of the same words and constructions used to talk about both domains [2]. Just as we might say that a saucer flew by, we can say that a day flew by. We can push forward a wheelbarrow or a meeting, believe that a wall or a semester is behind us, or worry that a moose or a birthday is approaching. Prior work has demonstrated that people do not just talk about time using spatial words; they also appear to use specific spatial representations when thinking about time. For example, English metaphors commonly place events on a horizontal mental timeline with the future in front (e.g., ‘looking forward to the year ahead of us’) and the past behind (e.g., ‘the worst is behind us’). Correspondingly, English speakers show evidence of horizontal front-back mental timelines. For example, they are faster to move their arm forward to indicate that an event is in the future and pull their arm back to indicate the past than for the reverse mapping [3]. They are also
Trends in Neurosciences, October 2018, Vol. 41, No. 10
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faster to judge that a word refers to the future if it is shown in front of an image of a person than if it is shown behind that person [4]. These findings suggest that English speakers mentally represent time in a way that accords with the front-back metaphors for time in the English language. The question is whether patterns in language actually play any role in constructing these mental representations. Patterns in language may simply reflect representations that have emerged through other means. Perhaps all humans develop the same front-back representations of time due to commonalities in physical experience and/or innate predispositions. To test this possibility, it is possible to compare representations of time in speakers of different languages. When languages rely on different spatial metaphors for time, do their speakers develop correspondingly different mental timelines? It turns out that while using spatial language to talk about time is very common across languages, languages differ considerably in the specific spatial words and constructions that are reused for time. For example, in English, as mentioned, metaphors typically put the past behind and the future in front. In Aymara, a language spoken in the Andes, the reverse is true. Past events are said to be in front and future events behind [5]. This pattern in language is also reflected in co-speech gestures. Aymara speakers gesture behind them when talking about future events and in front of them when talking about past events (compared to, e.g., Spanish speakers from the same region, who place the future in front both in gesture and in metaphors, as in English). Other cross-linguistic differences have been observed on the vertical axis. Unlike English, Mandarin commonly relies both on horizontal (front/back) and on vertical 652
(up/down) terms. In Mandarin, earlier events are said to be ‘up’ and later events are ‘down’, and such vertical metaphors are more systematic, productive, and frequent in Mandarin than in English. Correspondingly, Mandarin speakers are more likely to create vertical representations for time than are English speakers, including in non-linguistic tasks [6,7]. For example, Mandarin speakers are more likely than English speakers to place events on the vertical axis when pointing in space and more likely to arrange temporal progression picture sequences vertically. Furthermore, several features of language experience modulate the results. Mandarin-English bilinguals are more likely to arrange time vertically if they are more fluent in Mandarin, if they are tested in Mandarin (as opposed to in English), and if the instructions explicitly include vertical metaphors in Mandarin. That is, both long-term and immediate aspects of experience with vertical metaphors moderate how likely an individual is to arrange time vertically. Even in tasks that do not involve any linguistic stimuli or responses, Mandarin speakers still show an active earlier-is-up association between time and space that corresponds with linguistic metaphors in Mandarin. For example, in studies from our group [6,7], at each trial participants were shown two images, one after the other (e.g., Julia Roberts in her 20s followed by either a younger or an older Julia). The subject’s job was to indicate whether the second image shows a conceptually earlier or later time point compared to the first image. The response keys were arranged so that the ‘earlier’ key is either above the ‘later’ key, or below it. The keys were not labeled with words, and the images contained no language. Even in these non-linguistic tasks, Mandarin speakers show an implicit earlier-isup association; they are faster when the earlier key is above the later key than if the positions are reversed. English speakers
Trends in Neurosciences, October 2018, Vol. 41, No. 10
tested on the same task show either a significantly weaker effect than Mandarin speakers, or no evidence of a spatial association on the vertical axis. So far, we have established that speakers of different languages represent time differently in ways that correspond with patterns of metaphor in their respective languages. Beside metaphor, there are, of course, many other potential sources for establishing space-time mappings. For example, in addition to front-back representations of time, English speakers also represent time on the left-right axis. These representations place earlier events on the left and later events on the right. These left-right patterns emerge from practices associated with reading and writing and reverse for people who read language written from right to left. For example, speakers of Hebrew and Arabic show right-to-left mental timelines (e.g., [8,9]). More generally, finding correlations between space-time mappings in language and patterns in thinking cannot tell us whether language actually plays a causal role in constructing particular representations of time. For one thing, language is only one part of culture, and it is possible that patterns in metaphors and in language arise because of some other set of underlying cultural differences that are outside of language. How then, can we establish whether patterns in metaphorical language can indeed shape how people think? In one set of studies, Hendricks and Boroditsky [10] taught English speakers new metaphors for time. One group learned to say things like ‘Tuesday is above Wednesday’ (placing earlier events above), and the other group learned to say things like ‘Tuesday is below Wednesday’ (placing later events above). Participants then completed a non-linguistic time judgment task, the same as had been used in prior cross-linguistic work with English, Mandarin, and Hebrew speakers. Indeed, the
results showed that learning new metaphors in language created new spacetime associations. Furthermore, once learned, the new space-time associations became established beyond the linguistic system and were not susceptible to verbal interference. Representations newly learned from linguistic metaphor behaved just like those on the left-right axis that participants had acquired through years of visuospatial experience. This was true with respect to both verbal and visual interference. In other words, learning to talk about time in a new way created new non-linguistic representations of time.
depends on the set of spatial representa- Acknowledgments tions that are cognitively available (either Work in the Boroditsky lab is supported by the in the moment or in the cultural cognitive McDonnell Foundation and NSF BCS award repertoire more generally). For example, 1547901. stroke patients with left spatial neglect 1University of California, San Diego, CA, USA also neglect the culturally set ‘left’ side of time (for left-to-right reading patients, *Correspondence: [email protected] (L. Boroditsky). https://doi.org/10.1016/j.tins.2018.08.004 the left is the past) [11]. And speakers of languages that rely on cardinal or abso- References lute directions to represent space (e.g., 1. Boroditsky, L. (2011) How languages construct time. In Space, Time and Number in the Brain: Searching for the north, south, east, west in lieu of left/right) Foundations of Mathematical Thought (1st edn) (Dehaene, S. and Brannon, E., eds), pp. 333–341, Elsevier have been shown to arrange time in absolute space (e.g., proceeding east to west, 2. Clark, H. (1973) Space, time, semantics, and the child. In Cognitive Development and the Acquisition of Language rather than say left to right with respect to (Moore, T.E., ed.), pp. 27–64, Academic Press 3. Sell, A.J. and Kaschak, M.P. (2011) Processing time shifts the body) [12]. affects the execution of motor responses. Brain Lang. 117, 39–44
People in different cultures or groups have been shown to differ in whether they think of time as stationary or moving, limited or open ended, as distance or quantity, horizontal or vertical, oriented from left to right, right to left, front to back, back to front, or in cardinal space (e.g., East to West) [1]. How people conceptualize time appears to depend on how the languages they speak tend to talk about time, on the current linguistic context (what language is being spoken), and also on the particular metaphors being used to talk about time in the moment. It is notable that to represent time, people around the world so commonly rely on space. Beyond language and gesture, we spatialize time in cultural artifacts like graphs, timelines, orthography, clocks, sundials, hourglasses, and calendars. Indeed, how people think about time
One of the great mysteries of the human mind is our sophisticated ability for abstract reasoning. How are we able to think about things we can never see or touch? How do we come to represent and reason about domains like time, number, love, or justice when our experience of the world is physical, that is, accomplished through sensory perception and motor action. The ability to cognitively transcend the physical is one of the very hallmarks of human intelligence. The work described here offers a possible solution to this broader mystery. Representations of relatively more abstract notions (like time) can be constructed, in part, through analogical extensions from more experience-based domains (like space), with specific analogical mappings encouraged by patterns in culture, including those embedded in language.
4. Torralbo, A. et al. (2006) Flexible conceptual projection of time onto spatial frames of reference. Cogn. Sci. 30, 745– 757 5. Núñez, R.E. and Sweetser, E. (2006) With the future behind them: convergent evidence from Aymara language and gesture in the crosslinguistic comparison of spatial construals of time. Cogn. Sci. 30, 401–450 6. Boroditsky, L. et al. (2010) Do English and Mandarin speakers think about time differently? Cognition 118, 123–129 7. Fuhrman, O. et al. (2011) How linguistic and cultural forces shape conceptions of time: English and Mandarin time in 3D. Cogn. Sci. 35, 1305–1328 8. Tversky, B. et al. (1991) Crosscultural and developmentaltrends in graphic productions. Cogn. Psychol. 23, 515– 557 9. Fuhrman, O. and Boroditsky, L. (2010) Cross-cultural differences in mental representations of time: evidence from an implicit nonlinguistic task. Cogn. Sci. 34, 1430–1451 10. Hendricks, R.K. and Boroditsky, L. (2017) New space-time metaphors foster new mental representations of time. Top. Cogn. Sci. 9, 800–818 11. Saj, A. et al. (2014) Patients with left spatial neglect also neglect the “left side” of time. Psychol. Sci. 25, 207–214 12. Boroditsky, L. and Gaby, A. (2010) Remembrances of times east: absolute spatial representations of time in an Australian Aboriginal community. Psychol. Sci. 21, 16351639
Trends in Neurosciences, October 2018, Vol. 41, No. 10
653
programs among bilaterians, suggest Speakers of different languages that additional conserved features of think about time differently in motor networks await to be discovered. accordance with the spatial meta-
MN subtype identity also appears to play an instructive role in shaping connections within spinal premotor networks. Conversion of hypaxial MNs to a limb MN fate in mice, through mutation in the Hoxc9 gene, causes dramatic changes in the specificity of connections between MNs, spinal interneurons, and proprioceptive sensory neurons [12]. These changes in premotor input pattern appear to be a consequence in the altered position and dendritic architecture of the transformed MN populations. Although it is currently unknown whether these premotor connectivity alterations affect CPG function, their presence demonstrates that MNs play a critical role in shaping the connectivity and output patterns of locomotor circuits.
References 1. Jung, H. and Dasen, J.S. (2015) Evolution of patterning systems and circuit elements for locomotion. Dev. Cell 32, 408–422
Acknowledgments Work in the Dasen lab is supported by grants from the NIH (NINDS R01 NS062822, R21 NS099933). 1
Neuroscience Institute, Department of Neuroscience and Physiology, NYU School of Medicine, New York, NY 10016, USA *Correspondence: [email protected] (J.S. Dasen).
phors common in their languages. Furthermore, learning new spatial metaphors in language instills new non-linguistic representations of time, suggesting that language can play a causal role in constructing mental timelines.
https://doi.org/10.1016/j.tins.2018.07.013
2. Katz, P.S. (2016) Evolution of central pattern generators and rhythmic behaviours. Philos. Trans. R. Soc. Lond. B Biol. Sci. 371, 20150057 3. Arendt, D. (2018) Animal evolution: convergent nerve cords? Curr. Biol. 28, R225–R227 4. Kiehn, O. (2016) Decoding the organization of spinal circuits that control locomotion. Nat. Rev. Neurosci. 17, 224–238 5. Hagglund, M. et al. (2013) Optogenetic dissection reveals multiple rhythmogenic modules underlying locomotion. Proc. Natl. Acad. Sci. U. S. A. 110, 11589–11594 6. Marder, E. et al. (2015) Robust circuit rhythms in small circuits arise from variable circuit components and mechanisms. Curr. Opin. Neurobiol. 31, 156–163 7. Gao, S. et al. (2018) Excitatory motor neurons are local oscillators for backward locomotion. eLife 7, e29915 8. Sakurai, A. and Katz, P.S. (2017) Artificial synaptic rewiring demonstrates that distinct neural circuit configurations underlie homologous behaviors. Curr. Biol. 27, 1721–1734 9. Jung, H. et al. (2018) The ancient origins of neural substrates for land walking. Cell 172, 667–682 10. Dasen, J.S. (2017) Master or servant? Emerging roles for motor neuron subtypes in the construction and evolution of locomotor circuits. Curr. Opin. Neurobiol. 42, 25–32
Comparative studies have revealed both 11. Wright, T.M. and Calabrese, R.L. (2011) Contribution of motoneuron intrinsic properties to fictive motor pattern highly conserved and divergent mechageneration. J. Neurophysiol. 106, 538–553 nisms contributing to the development 12. Baek, M. et al. (2017) Columnar-intrinsic cues shape and functional properties of locomotor premotor input specificity in locomotor circuits. Cell Rep. 21, 867–877 rhythms. Whether early nervous systems contained circuit elements that are still used in modern species for locomotor control remains to be determined. Special Issue: Time in the Brain Recent methods for sequencing large numbers of neuronal types, in conjunc- Forum tion with comparisons across multiple species, should allow us to infer what common circuit elements contribute to the establishment of locomotor behaviors. The prevalence of locomotor CPGs in animals, as well as shared early Lera Boroditsky1,* patterning and MN specification
Language and the Construction of Time through Space
What is the role of language in constructing our representations of time? Time is a central topic of conversation in many languages. In English, the word ‘time’ is the most frequent noun, with other temporal words such as ‘day’ and ‘year’ also ranking in the top ten [1]. Do the ways we talk about time help construct the ways we think about it? In English, talk about time strongly overlaps with talk about space, with many of the same words and constructions used to talk about both domains [2]. Just as we might say that a saucer flew by, we can say that a day flew by. We can push forward a wheelbarrow or a meeting, believe that a wall or a semester is behind us, or worry that a moose or a birthday is approaching. Prior work has demonstrated that people do not just talk about time using spatial words; they also appear to use specific spatial representations when thinking about time. For example, English metaphors commonly place events on a horizontal mental timeline with the future in front (e.g., ‘looking forward to the year ahead of us’) and the past behind (e.g., ‘the worst is behind us’). Correspondingly, English speakers show evidence of horizontal front-back mental timelines. For example, they are faster to move their arm forward to indicate that an event is in the future and pull their arm back to indicate the past than for the reverse mapping [3]. They are also
Trends in Neurosciences, October 2018, Vol. 41, No. 10
651
faster to judge that a word refers to the future if it is shown in front of an image of a person than if it is shown behind that person [4]. These findings suggest that English speakers mentally represent time in a way that accords with the front-back metaphors for time in the English language. The question is whether patterns in language actually play any role in constructing these mental representations. Patterns in language may simply reflect representations that have emerged through other means. Perhaps all humans develop the same front-back representations of time due to commonalities in physical experience and/or innate predispositions. To test this possibility, it is possible to compare representations of time in speakers of different languages. When languages rely on different spatial metaphors for time, do their speakers develop correspondingly different mental timelines? It turns out that while using spatial language to talk about time is very common across languages, languages differ considerably in the specific spatial words and constructions that are reused for time. For example, in English, as mentioned, metaphors typically put the past behind and the future in front. In Aymara, a language spoken in the Andes, the reverse is true. Past events are said to be in front and future events behind [5]. This pattern in language is also reflected in co-speech gestures. Aymara speakers gesture behind them when talking about future events and in front of them when talking about past events (compared to, e.g., Spanish speakers from the same region, who place the future in front both in gesture and in metaphors, as in English). Other cross-linguistic differences have been observed on the vertical axis. Unlike English, Mandarin commonly relies both on horizontal (front/back) and on vertical 652
(up/down) terms. In Mandarin, earlier events are said to be ‘up’ and later events are ‘down’, and such vertical metaphors are more systematic, productive, and frequent in Mandarin than in English. Correspondingly, Mandarin speakers are more likely to create vertical representations for time than are English speakers, including in non-linguistic tasks [6,7]. For example, Mandarin speakers are more likely than English speakers to place events on the vertical axis when pointing in space and more likely to arrange temporal progression picture sequences vertically. Furthermore, several features of language experience modulate the results. Mandarin-English bilinguals are more likely to arrange time vertically if they are more fluent in Mandarin, if they are tested in Mandarin (as opposed to in English), and if the instructions explicitly include vertical metaphors in Mandarin. That is, both long-term and immediate aspects of experience with vertical metaphors moderate how likely an individual is to arrange time vertically. Even in tasks that do not involve any linguistic stimuli or responses, Mandarin speakers still show an active earlier-is-up association between time and space that corresponds with linguistic metaphors in Mandarin. For example, in studies from our group [6,7], at each trial participants were shown two images, one after the other (e.g., Julia Roberts in her 20s followed by either a younger or an older Julia). The subject’s job was to indicate whether the second image shows a conceptually earlier or later time point compared to the first image. The response keys were arranged so that the ‘earlier’ key is either above the ‘later’ key, or below it. The keys were not labeled with words, and the images contained no language. Even in these non-linguistic tasks, Mandarin speakers show an implicit earlier-isup association; they are faster when the earlier key is above the later key than if the positions are reversed. English speakers
Trends in Neurosciences, October 2018, Vol. 41, No. 10
tested on the same task show either a significantly weaker effect than Mandarin speakers, or no evidence of a spatial association on the vertical axis. So far, we have established that speakers of different languages represent time differently in ways that correspond with patterns of metaphor in their respective languages. Beside metaphor, there are, of course, many other potential sources for establishing space-time mappings. For example, in addition to front-back representations of time, English speakers also represent time on the left-right axis. These representations place earlier events on the left and later events on the right. These left-right patterns emerge from practices associated with reading and writing and reverse for people who read language written from right to left. For example, speakers of Hebrew and Arabic show right-to-left mental timelines (e.g., [8,9]). More generally, finding correlations between space-time mappings in language and patterns in thinking cannot tell us whether language actually plays a causal role in constructing particular representations of time. For one thing, language is only one part of culture, and it is possible that patterns in metaphors and in language arise because of some other set of underlying cultural differences that are outside of language. How then, can we establish whether patterns in metaphorical language can indeed shape how people think? In one set of studies, Hendricks and Boroditsky [10] taught English speakers new metaphors for time. One group learned to say things like ‘Tuesday is above Wednesday’ (placing earlier events above), and the other group learned to say things like ‘Tuesday is below Wednesday’ (placing later events above). Participants then completed a non-linguistic time judgment task, the same as had been used in prior cross-linguistic work with English, Mandarin, and Hebrew speakers. Indeed, the
results showed that learning new metaphors in language created new spacetime associations. Furthermore, once learned, the new space-time associations became established beyond the linguistic system and were not susceptible to verbal interference. Representations newly learned from linguistic metaphor behaved just like those on the left-right axis that participants had acquired through years of visuospatial experience. This was true with respect to both verbal and visual interference. In other words, learning to talk about time in a new way created new non-linguistic representations of time.
depends on the set of spatial representa- Acknowledgments tions that are cognitively available (either Work in the Boroditsky lab is supported by the in the moment or in the cultural cognitive McDonnell Foundation and NSF BCS award repertoire more generally). For example, 1547901. stroke patients with left spatial neglect 1University of California, San Diego, CA, USA also neglect the culturally set ‘left’ side of time (for left-to-right reading patients, *Correspondence: [email protected] (L. Boroditsky). https://doi.org/10.1016/j.tins.2018.08.004 the left is the past) [11]. And speakers of languages that rely on cardinal or abso- References lute directions to represent space (e.g., 1. Boroditsky, L. (2011) How languages construct time. In Space, Time and Number in the Brain: Searching for the north, south, east, west in lieu of left/right) Foundations of Mathematical Thought (1st edn) (Dehaene, S. and Brannon, E., eds), pp. 333–341, Elsevier have been shown to arrange time in absolute space (e.g., proceeding east to west, 2. Clark, H. (1973) Space, time, semantics, and the child. In Cognitive Development and the Acquisition of Language rather than say left to right with respect to (Moore, T.E., ed.), pp. 27–64, Academic Press 3. Sell, A.J. and Kaschak, M.P. (2011) Processing time shifts the body) [12]. affects the execution of motor responses. Brain Lang. 117, 39–44
People in different cultures or groups have been shown to differ in whether they think of time as stationary or moving, limited or open ended, as distance or quantity, horizontal or vertical, oriented from left to right, right to left, front to back, back to front, or in cardinal space (e.g., East to West) [1]. How people conceptualize time appears to depend on how the languages they speak tend to talk about time, on the current linguistic context (what language is being spoken), and also on the particular metaphors being used to talk about time in the moment. It is notable that to represent time, people around the world so commonly rely on space. Beyond language and gesture, we spatialize time in cultural artifacts like graphs, timelines, orthography, clocks, sundials, hourglasses, and calendars. Indeed, how people think about time
One of the great mysteries of the human mind is our sophisticated ability for abstract reasoning. How are we able to think about things we can never see or touch? How do we come to represent and reason about domains like time, number, love, or justice when our experience of the world is physical, that is, accomplished through sensory perception and motor action. The ability to cognitively transcend the physical is one of the very hallmarks of human intelligence. The work described here offers a possible solution to this broader mystery. Representations of relatively more abstract notions (like time) can be constructed, in part, through analogical extensions from more experience-based domains (like space), with specific analogical mappings encouraged by patterns in culture, including those embedded in language.
4. Torralbo, A. et al. (2006) Flexible conceptual projection of time onto spatial frames of reference. Cogn. Sci. 30, 745– 757 5. Núñez, R.E. and Sweetser, E. (2006) With the future behind them: convergent evidence from Aymara language and gesture in the crosslinguistic comparison of spatial construals of time. Cogn. Sci. 30, 401–450 6. Boroditsky, L. et al. (2010) Do English and Mandarin speakers think about time differently? Cognition 118, 123–129 7. Fuhrman, O. et al. (2011) How linguistic and cultural forces shape conceptions of time: English and Mandarin time in 3D. Cogn. Sci. 35, 1305–1328 8. Tversky, B. et al. (1991) Crosscultural and developmentaltrends in graphic productions. Cogn. Psychol. 23, 515– 557 9. Fuhrman, O. and Boroditsky, L. (2010) Cross-cultural differences in mental representations of time: evidence from an implicit nonlinguistic task. Cogn. Sci. 34, 1430–1451 10. Hendricks, R.K. and Boroditsky, L. (2017) New space-time metaphors foster new mental representations of time. Top. Cogn. Sci. 9, 800–818 11. Saj, A. et al. (2014) Patients with left spatial neglect also neglect the “left side” of time. Psychol. Sci. 25, 207–214 12. Boroditsky, L. and Gaby, A. (2010) Remembrances of times east: absolute spatial representations of time in an Australian Aboriginal community. Psychol. Sci. 21, 16351639
Trends in Neurosciences, October 2018, Vol. 41, No. 10
653