Space in Hand and Mind: Gesture and Spatial Frames of Reference in Bilingual Mexico.

Speakers of many languages prefer allocentric frames of reference (FoRs) when talking about small-scale space, using words like "east" or "downhill." Ethnographic work has suggested that this preference is also reflected in how such speakers gesture. Here, we investigate this possibility with a field experiment in Juchitán, Mexico. In Juchitán, a preferentially allocentric language (Isthmus Zapotec) coexists with a preferentially egocentric one (Spanish). Using a novel task, we elicited spontaneous co-speech gestures about small-scale motion events (e.g., toppling blocks) in Zapotec-dominant speakers and in balanced Zapotec-Spanish bilinguals. Consistent with prior claims, speakers' spontaneous gestures reliably reflected either an egocentric or allocentric FoR. The use of the egocentric FoR was predicted-not by speakers' dominant language or the language they used in the task-but by mastery of words for "right" and "left," as well as by properties of the event they were describing. Additionally, use of the egocentric FoR in gesture predicted its use in a separate nonlinguistic memory task, suggesting a cohesive cognitive style. Our results show that the use of spatial FoRs in gesture is pervasive, systematic, and shaped by several factors. Spatial gestures, like other forms of spatial conceptualization, are thus best understood within broader ecologies of communication and cognition.

The career of measurement.

Units as they exist today are highly abstract. Meters, miles, and other modern measures have no obvious basis in tangible phenomena and can be applied broadly across domains. Historical examples suggest, however, that units have not always been so abstract. Here, we examine this issue systematically. We begin by analyzing linear measures in the Oxford English Dictionary (OED) and in an ethnographic database that spans 114 cultures (HRAF). Our survey of both datasets shows, first, that early length units have mostly come from concrete sources-body parts, artifacts, events, and other tangible phenomena-and, second, that they have often been tied to particular contexts. Measurement units have thus undergone a shift from highly concrete to highly abstract. How did this shift happen? Drawing on historical surveys and case studies-as well as data from the OED and HRAF-we next propose a reconstruction of how abstract units might have evolved gradually through a series of overlapping stages. We also consider the cognitive processes that underpin this evolution-in particular, comparison. Finally, we discuss the cognitive origins of units. Units are not only slow to emerge historically, they are also slow to be acquired developmentally, and mastering them appears to have cognitive consequences. Taken together, these observations suggest that units are not inevitable intuitions, but are best thought of as culturally evolved cognitive tools. By analyzing the career of measurement in detail, we illustrate how such tools-abstract as they are today-can arise from concrete, often bodily origins.

The Preference for Pointing With the Hand Is Not Universal.

Pointing is a cornerstone of human communication, but does it take the same form in all cultures? Manual pointing with the index finger appears to be used universally, and it is often assumed to be universally preferred over other forms. Non-manual pointing with the head and face has also been widely attested, but it is usually considered of marginal significance, both empirically and theoretically. Here, we challenge this assumed marginality. Using a novel communication task, we investigated pointing preferences in the Yupno of Papua New Guinea and in U.S. undergraduates. Speakers in both groups pointed at similar rates, but form preferences differed starkly: The Yupno participants used non-manual pointing (nose- and head-pointing) numerically more often than manual pointing, whereas the U.S. participants stuck unwaveringly to index-finger pointing. The findings raise questions about why groups differ in their pointing preferences and, more broadly, about why humans communicate in the ways they do.

When Gesture Becomes Analogy.

Analogy researchers do not often examine gesture, and gesture researchers do not often borrow ideas from the study of analogy. One borrowable idea from the world of analogy is the importance of distinguishing between attributes and relations. Gentner (, ) observed that some metaphors highlight attributes and others highlight relations, and called the latter analogies. Mirroring this logic, we observe that some metaphoric gestures represent attributes and others represent relations, and propose to call the latter analogical gestures. We provide examples of such analogical gestures and show how they relate to the categories of iconic and metaphoric gestures described previously. Analogical gestures represent different types of relations and different degrees of relational complexity, and sometimes cohere into larger analogical models. Treating analogical gestures as a distinct phenomenon prompts new questions and predictions, and illustrates one way that the study of gesture and the study of analogy can be mutually informative.

Where Does the Ordered Line Come From? Evidence From a Culture of Papua New Guinea.

Number lines, calendars, and measuring sticks all represent order along some dimension (e.g., magnitude) as position on a line. In high-literacy, industrialized societies, this principle of spatial organization- linear order-is a fixture of visual culture and everyday cognition. But what are the principle's origins, and how did it become such a fixture? Three studies investigated intuitions about linear order in the Yupno, members of a culture of Papua New Guinea that lacks conventional representations involving ordered lines, and in U.S. undergraduates. Presented with cards representing differing sizes and numerosities, both groups arranged them using linear order or sometimes spatial grouping, a competing principle. But whereas the U.S. participants produced ordered lines in all tasks, strongly favoring a left-to-right format, the Yupno produced them less consistently, and with variable orientations. Conventional linear representations are thus not necessary to spark the intuition of linear order-which may have other experiential sources-but they nonetheless regiment when and how the principle is used.

Uphill and Downhill in a Flat World: The Conceptual Topography of the Yupno House.

Speakers of many languages around the world rely on body-based contrasts (e.g., left/right) for spatial communication and cognition. Speakers of Yupno, a language of Papua New Guinea's mountainous interior, rely instead on an environment-based uphill/downhill contrast. Body-based contrasts are as easy to use indoors as outdoors, but environment-based contrasts may not be. Do Yupno speakers still use uphill/downhill contrasts indoors and, if so, how? We report three studies on spatial communication within the Yupno house. Even in this flat world, uphill/downhill contrasts are pervasive. However, the terms are not used according to the slopes beyond the house's walls, as reported in other groups. Instead, the house is treated as a microworld, with a "conceptual topography" that is strikingly reminiscent of the physical topography of the Yupno valley. The phenomenon illustrates some of the distinctive properties of environment-based reference systems, as well as the universal power and plasticity of spatial contrasts.

Spatial analogies pervade complex relational reasoning: Evidence from spontaneous gestures.

How do people think about complex phenomena like the behavior of ecosystems? Here we hypothesize that people reason about such relational systems in part by creating spatial analogies, and we explore this possibility by examining spontaneous gestures. In two studies, participants read a written lesson describing positive and negative feedback systems and then explained the differences between them. Though the lesson was highly abstract and people were not instructed to gesture, people produced spatial gestures in abundance during their explanations. These gestures used space to represent simple abstract relations (e.g., increase) and sometimes more complex relational structures (e.g., negative feedback). Moreover, over the course of their explanations, participants' gestures often cohered into larger analogical models of relational structure. Importantly, the spatial ideas evident in the hands were largely unaccompanied by spatial words. Gesture thus suggests that spatial analogies are pervasive in complex relational reasoning, even when language does not.

The Continuity of Metaphor: Evidence From Temporal Gestures.

Reasoning about bedrock abstract concepts such as time, number, and valence relies on spatial metaphor and often on multiple spatial metaphors for a single concept. Previous research has documented, for instance, both future-in-front and future-to-right metaphors for time in English speakers. It is often assumed that these metaphors, which appear to have distinct experiential bases, remain distinct in online temporal reasoning. In two studies we demonstrate that, contra this assumption, people systematically combine these metaphors. Evidence for this combination was found in both directly elicited (Study 1) and spontaneous co-speech (Study 2) gestures about time. These results provide first support for the hypothesis that the metaphorical representation of time, and perhaps other abstract domains as well, involves the continuous co-activation of multiple metaphors rather than the selection of only one.

Gesture for Linguists: A Handy Primer.

Humans communicate using language, but they also communicate using gesture - spontaneous movements of the hands and body that universally accompany speech. Gestures can be distinguished from other movements, segmented, and assigned meaning based on their forms and functions. Moreover, gestures systematically integrate with language at all levels of linguistic structure, as evidenced in both production and perception. Viewed typologically, gesture is universal, but nevertheless exhibits constrained variation across language communities (as does language itself ). Finally, gesture has rich cognitive dimensions in addition to its communicative dimensions. In overviewing these and other topics, we show that the study of language is incomplete without the study of its communicative partner, gesture.

The tangle of space and time in human cognition.

Everyday concepts of duration, of sequence, and of past, present, and future are fundamental to how humans make sense of experience. In culture after culture, converging evidence from language, co-speech gesture, and behavioral tasks suggests that humans handle these elusive yet indispensable notions by construing them spatially. Where do these spatial construals come from and why do they take the particular, sometimes peculiar, spatial forms that they do? As researchers across the cognitive sciences pursue these questions on different levels--cultural, developmental--in diverse populations and with new methodologies, clear answers will depend upon a shared and nuanced set of theoretical distinctions. Time is not a monolith, but rather a mosaic of construals with distinct properties and origins.

Contours of time: topographic construals of past, present, and future in the Yupno valley of Papua New Guinea.

Time, an everyday yet fundamentally abstract domain, is conceptualized in terms of space throughout the world's cultures. Linguists and psychologists have presented evidence of a widespread pattern in which deictic time-past, present, and future-is construed along the front/back axis, a construal that is linear and ego-based. To investigate the universality of this pattern, we studied the construal of deictic time among the Yupno, an indigenous group from the mountains of Papua New Guinea, whose language makes extensive use of allocentric topographic (uphill/downhill) terms for describing spatial relations. We measured the pointing direction of Yupno speakers' gestures-produced naturally and without prompting-as they explained common expressions related to the past, present, and future. Results show that the Yupno spontaneously construe deictic time spatially in terms of allocentric topography: the past is construed as downhill, the present as co-located with the speaker, and the future as uphill. Moreover, the Yupno construal is not linear, but exhibits a particular geometry that appears to reflect the local terrain. The findings shed light on how, our universal human embodiment notwithstanding, linguistic, cultural, and environmental pressures come to shape abstract concepts.

Number concepts without number lines in an indigenous group of Papua New Guinea.

BACKGROUND: The generic concept of number line, which maps numbers to unidimensional space, is a fundamental concept in mathematics, but its cognitive origins are uncertain. Two defining criteria of the number line are that (i) there is a mapping of each individual number (or numerosity) under consideration onto a specific location on the line, and (ii) that the mapping defines a unidimensional space representing numbers with a metric--a distance function. It has been proposed that the number line is based on a spontaneous universal human intuition, rooted directly in brain evolution, that maps number magnitude to linear space with a metric. To date, no culture lacking this intuition has been documented. METHODOLOGY/PRINCIPAL FINDINGS: By means of a number line task, we investigated the universality proposal with the Yupno of Papua New Guinea. Unschooled adults did exhibit a number-to-space mapping (criterion i) but, strikingly, despite having precise cardinal number concepts, they located numbers only on the endpoints, thus failing to use the extent of the line. The produced mapping was bi-categorical and metric-free, in violation of criterion ii. In contrast, Yupnos with scholastic experience used the extent of the segment according to known standards, but they did so not as evenly as western controls, exhibiting a bias towards the endpoints. CONCLUSIONS/SIGNIFICANCE: Results suggest that cardinal number concepts can exist independently from number line representations. They also suggest that the number line mapping, although ubiquitous in the modern world, is not universally spontaneous, but rather seems to be learned through--and continually reinforced by--specific cultural practices.