The importance of gesture in children's spatial reasoning

On average, men outperform women on mental rotation tasks. Even boys as young as 4 1/2 perform better than girls on simplified spatial transformation tasks. The goal of our study was to explore ways of improving 5-year-olds' performance on a spatial transformation task and to examine the strategies children use to solve this task. We found that boys performed better than girls before training and that both boys and girls improved with training, whether they were given explicit instruction or just practice. Regardless of training condition, the more children gestured about moving the pieces when asked to explain how they solved the spatial transformation task, the better they performed on the task, with boys gesturing about movement significantly more (and performing better) than girls. Gesture thus provides useful information about children's spatial strategies, raising the possibility that gesture training may be particularly effective in improving children's mental rotation skills.     

Children's creation of algorithms: simulations and gestures

Experiments showed that children are able to create algorithms, that is, sequences of operations that solve problems, and that their gestures help them to do so. The theory of mental models, which is implemented in a computer program, postulates that the creation of algorithms depends on mental simulations that unfold in time. Gestures are outward signs of moves and they help the process. We tested 10-year-old children, because they can plan, and because they gesture more than adults. They were able to rearrange the order of 6 cars in a train (using a siding), and the difficulty of the task depended on the number of moves in minimal solutions (Experiment 1). They were also able to devise informal algorithms to rearrange the order of cars when they were not allowed to move the cars, and the difficulty of the task depended on the complexity of the algorithms (Experiment 2). When children were prevented from gesturing as they formulated algorithms, the accuracy of their algorithms declined by13% (Experiment 3). We discuss the implications of these results.     

Gesturing during mental problem solving reduces eye movements,especially for individuals with lower visual working memory capacity

Non-communicative hand gestures have been found to benefit problem-solving performance. These gestures seem to compensate for limited internal cognitive capacities, such as visual working memory capacity. Yet, it is not clear how gestures might perform this cognitive function. One hypothesis is that gesturing is a means to spatially index mental simulations, thereby reducing the need for visually projecting the mental simulation onto the visual presentation of the task. If that hypothesis is correct, less eye movements should be made when participants gesture during problem solving than when they do not gesture. We therefore used mobile eye tracking to investigate the effect of co-thought gesturing and visual working memory capacity on eye movements during mental solving of the Tower of Hanoi problem. Results revealed that gesturing indeed reduced the number of eye movements (lower saccade counts), especially for participants with a relatively lower visual working memory capacity. Subsequent problem-solving performance was not affected by having (not) gestured during the mental solving phase. The current findings suggest that our understanding of gestures in problem solving could be improved by taking into account eye movements during gesturing.     

Gesture changes thought by grounding it in action

When people talk, they gesture. We show that gesture introduces action information into speakers' mental representations, which, in turn, affect subsequent performance. In Experiment 1, participants solved the Tower of Hanoi task (TOH1), explained (with gesture) how they solved it, and solved it again (TOH2). For all participants, the smallest disk in TOH1 was the lightest and could be lifted with one hand. For some participants (no-switch group), the disks in TOH2 were identical to those in TOH1. For others (switch group), the disk weights in TOH2 were reversed (so that the smallest disk was the heaviest and could not be lifted with one hand). The more the switch group's gestures depicted moving the smallest disk one-handed, the worse they performed on TOH2. This was not true for the no-switch group, nor for the switch group in Experiment 2, who skipped the explanation step and did not gesture. Gesturing grounds people's mental representations in action. When gestures are no longer compatible with the action constraints of a task, problem solving suffers.     

Spontaneous gestures influence strategy choices in problem solving

Do gestures merely reflect problem-solving processes, or do they play a functional role in problem solving? We hypothesized that gestures highlight and structure perceptual-motor information, and thereby make such information more likely to be used in problem solving. Participants in two experiments solved problems requiring the prediction of gear movement, either with gesture allowed or with gesture prohibited. Such problems can be correctly solved using either a perceptual-motor strategy (simulation of gear movements) or an abstract strategy (the parity strategy). Participants in the gesture-allowed condition were more likely to use perceptual-motor strategies than were participants in the gesture-prohibited condition. Gesture promoted use of perceptual-motor strategies both for participants who talked aloud while solving the problems (Experiment 1) and for participants who solved the problems silently (Experiment 2). Thus, spontaneous gestures influence strategy choices in problem solving.     

The Role of Gesture in Supporting Mental Representations: The Case of Mental Abacus Arithmetic

People frequently gesture when problem‐solving, particularly on tasks that require spatial transformation. Gesture often facilitates task performance by interacting with internal mental representations, but how this process works is not well understood. We investigated this question by exploring the case of mental abacus (MA), a technique in which users not only imagine moving beads on an abacus to compute sums, but also produce movements in gestures that accompany the calculations. Because the content of MA is transparent and readily manipulated, the task offers a unique window onto how gestures interface with mental representations. We find that the size and number of MA gestures reflect the length and difficulty of math problems. Also, by selectively interfering with aspects of gesture, we find that participants perform significantly worse on MA under motor interference, but that perceptual feedback is not critical for success on the task. We conclude that premotor processes involved in the planning of gestures are critical to mental representation in MA.     

Individual differences in mental rotation: what does gesture tell us?

Gestures are common when people convey spatial information, for example, when they give directions or describe motion in space. Here, we examine the gestures speakers produce when they explain how they solved mental rotation problems (Shepard and Meltzer in Science 171:701–703, 1971). We asked whether speakers gesture differently while describing their problems as a function of their spatial abilities. We found that low-spatial individuals (as assessed by a standard paper-and-pencil measure) gestured more to explain their solutions than high-spatial individuals. While this finding may seem surprising, finer-grained analyses showed that low-spatial participants used gestures more often than high-spatial participants to convey “static only” information but less often than high-spatial participants to convey dynamic information. Furthermore, the groups differed in the types of gestures used to convey static information: high-spatial individuals were more likely than low-spatial individuals to use gestures that captured the internal structure of the block forms. Our gesture findings thus suggest that encoding block structure may be as important as rotating the blocks in mental spatial transformation.     

Central executive involvement in children's spatial memory

Previous research with adults found that spatial short-term and working memory tasks impose similar demands on executive resources. We administered spatial short-term and working memory tasks to 8- and 11-year-olds in three separate experiments. In Experiments 1 and 2 an executive suppression task (random number generation) was found to impair performances on a short-term memory task (Corsi blocks), a working memory task (letter rotation), and a spatial visualisation task (paper folding). In Experiment 3 an articulatory suppression task only impaired performance on the working memory task. These results suggest that short-term and working memory performances are dependent on executive resources. The degree to which the short-term memory task was dependent on executive resources was expected to be related to the amount of experience children have had with such tasks. Yet we found no significant age-related suppression effects. This was attributed to differences in employment of cognitive strategies by the older children.     

Central executive involvement in children's spatial memory

Previous research with adults found that spatial short-term and working memory tasks impose similar demands on executive resources. We administered spatial short-term and working memory tasks to 8- and 11-year-olds in three separate experiments. In Experiments 1 and 2 an executive suppression task (random number generation) was found to impair performances on a short-term memory task (Corsi blocks), a working memory task (letter rotation), and a spatial visualisation task (paper folding). In Experiment 3 an articulatory suppression task only impaired performance on the working memory task. These results suggest that short-term and working memory performances are dependent on executive resources. The degree to which the short-term memory task was dependent on executive resources was expected to be related to the amount of experience children have had with such tasks. Yet we found no significant age-related suppression effects. This was attributed to differences in employment of cognitive strategies by the older children.     

Speech and gesture in spatial language and cognition among the Yucatec Mayas

In previous analyses of the influence of language on cognition, speech has been the main channel examined. In studies conducted among Yucatec Mayas, efforts to determine the preferred frame of reference in use in this community have failed to reach an agreement (Bohnemeyer & Stolz, 2006; Levinson, 2003 vs. Le Guen, 2006, 2009). This paper argues for a multimodal analysis of language that encompasses gesture as well as speech, and shows that the preferred frame of reference in Yucatec Maya is only detectable through the analysis of co-speech gesture and not through speech alone. A series of experiments compares knowledge of the semantics of spatial terms, performance on nonlinguistic tasks and gestures produced by men and women. The results show a striking gender difference in the knowledge of the semantics of spatial terms, but an equal preference for a geocentric frame of reference in nonverbal tasks. In a localization task, participants used a variety of strategies in their speech, but they all exhibited a systematic preference for a geocentric frame of reference in their gestures.     

Co‐thought gestures in children's mental problem solving: Prevalence and effects on subsequent performance

Co‐thought gestures are understudied as compared to co‐speech gestures yet, may provide insight into cognitive functions of gestures that are independent of speech processes. A recent study with adults showed that co‐thought gesticulation occurred spontaneously during mental preparation of problem solving. Moreover, co‐thought gesturing (either spontaneous or instructed) during mental preparation was effective for subsequent solving of the Tower of Hanoi under conditions of high cognitive load (i.e., when visual working memory capacity was limited and when the task was more difficult). In this preregistered study ( https://osf.io/dreks/ ), we investigated whether co‐thought gestures would also spontaneously occur and would aid problem‐solving processes in children (N = 74; 8–12 years old) under high load conditions. Although children also spontaneously used co‐thought gestures during mental problem solving, this did not aid their subsequent performance when physically solving the problem. If these null results are on track, co‐thought gesture effects may be different in adults and children.     

Do sequence-space synaesthetes have better spatial imagery skills? Maybe not

Sequence-space synaesthesia is a type of visuo-spatial imagery in which numbers or calendar units are experienced to occupy locations in space. Previous studies have claimed that these synaesthetes (1) have stronger self-reported visual (but not spatial) imagery and (2) perform unusually well on mental rotation tasks that are usually taken to reflect spatial (but not visual) imagery. To further investigate whether this form of synaesthesia is related to spatial imagery, we compared synaesthetes to controls on the Object Spatial Imagery Questionnaire, a paper folding test and a mental rotation task. The synaesthetes did not differ from controls in self-reported spatial imagery, but showed a strong trend to report better visual imagery, replicating previously reported data patterns. Consistent with this, their paper folding and mental rotation performance was no better than controls. We also confirmed that, in our pooled sample, performance on both these tasks was positively correlated with self-reported spatial imagery. We suggest our data are more consistent with the view that sequence-space synaesthesia is related to visual than to spatial imagery, and we suggest reasons why previous studies may have found superior mental rotation performance.     

Time does not flow without language: Spatial distance affects temporal duration regardless of movement or direction

Much evidence has suggested that people conceive of time as flowing directionally in transverse space (e.g., from left to right for English speakers). However, this phenomenon has never been tested in a fully nonlinguistic paradigm where neither stimuli nor task use linguistic labels, which raises the possibility that time is directional only when reading/writing direction has been evoked. In the present study, English-speaking participants viewed a video where an actor sang a note while gesturing and reproduced the duration of the sung note by pressing a button. Results showed that the perceived duration of the note was increased by a long-distance gesture, relative to a short-distance gesture. This effect was equally strong for gestures moving from left to right and from right to left and was not dependent on gestures depicting movement through space; a weaker version of the effect emerged with static gestures depicting spatial distance. Since both our gesture stimuli and temporal reproduction task were nonlinguistic, we conclude that the spatial representation of time is nondirectional: Movement contributes, but is not necessary, to the representation of temporal information in a transverse timeline.     

Serial gesturing by wild chimpanzees: its nature and function for communication

Chimpanzees at Budongo, Uganda, regularly gesture in series, including ‘bouts’ of gesturing that include response waiting and ‘sequences’ of rapid-fire gesturing without pauses. We examined the distribution and correlates of 723 sequences and 504 bouts for clues to the function of multigesture series. Gesturing by older chimpanzees was more likely to be successful, but the success rate of any particular gesture did not vary with signaller age. Rather, older individuals were more likely to choose successful gestures, and these highly successful gestures were more often used singly. These patterns explain why bouts were recorded most in younger animals, whereas older chimpanzees relied more on single gestures: bouts are best interpreted as a consequence of persistence in the face of failure. When at least one gesture of a successful type occurred in a sequence, that sequence was more likely to be successful; overall, however, sequences were less successful than single gestures. We suggest that young chimpanzees use sequences as a ‘fail-safe’ strategy: because they have the innate potential to produce a large and redundant repertoire of gestures but lack knowledge of which of them would be most efficient. Using sequences increases the chance of giving one effective gesture and also allows users to learn the most effective types. As they do so, they need to use sequences less; sequences may remain important for subtle interpersonal adjustment, especially in play. This ‘Repertoire Tuning’ hypothesis explains a number of results previously reported from chimpanzee gesturing.     

Gesture Helps,Only If You Need It: Inhibiting Gesture Reduces Tip-of-the-Tongue Resolution for Those With Weak Short-Term Memory

People frequently gesture when a word is on the tip of their tongue (TOT), yet research is mixed as to whether and why gesture aids lexical retrieval. We tested three accounts: the lexical retrieval hypothesis, which predicts that semantically related gestures facilitate successful lexical retrieval; the cognitive load account, which predicts that matching gestures facilitate lexical retrieval only when retrieval is hard, as in the case of a TOT; and the motor movement account, which predicts that any motor movements should support lexical retrieval. In Experiment 1 (a between-subjects study; N = 90), gesture inhibition, but not neck inhibition, affected TOT resolution but not overall lexical retrieval; participants in the gesture-inhibited condition resolved fewer TOTs than participants who were allowed to gesture. When participants could gesture, they produced more representational gestures during resolved than unresolved TOTs, a pattern not observed for meaningless motor movements (e.g., beats). However, the effect of gesture inhibition on TOT resolution was not uniform; some participants resolved many TOTs, while others struggled. In Experiment 2 (a within-subjects study; N = 34), the effect of gesture inhibition was traced to individual differences in verbal, not spatial short-term memory (STM) span; those with weaker verbal STM resolved fewer TOTs when unable to gesture. This relationship between verbal STM and TOT resolution was not observed when participants were allowed to gesture. Taken together, these results fit the cognitive load account; when lexical retrieval is hard, gesture effectively reduces the cognitive load of TOT resolution for those who find the task especially taxing.     

Mental rotation: cross-task training and generalization

It is well established that performance on standard mental rotation tasks improves with training (Peters et al., 1995), but thus far there is little consensus regarding the degree of transfer to other tasks which also involve mental rotation. In Experiment 1, we assessed the effect of mental rotation training on participants' Mental Rotation Test (MRT) scores. Twenty-eight participants were randomly assigned to one of three groups: a "One-Day Training," "Spaced Training," or "No Training" group. Participants who received training achieved higher scores on the MRT, an advantage that was still evident after 1 week. Distribution of training did not affect performance. Experiment 2 assessed generalization of mental rotation training to a more complex mental rotation task, laparoscopic surgery. Laparoscopic surgical skills were assessed using Fundamentals of Laparoscopic Surgery (FLS) tasks. Thirty-four participants were randomly assigned to a "Full Mental Rotation Training, MRT and FLS," "MRT and FLS," or "FLS-only" group. MRT results from Experiment 1 were replicated and mental rotation training was found to elicit higher scores on the MRT. Further, mental rotation training was found to generalize to certain laparoscopic surgical tasks. Participants who obtained mental rotation training performed significantly better on mental-rotation dependent surgical tasks than participants who did not receive training. Therefore, surgical training programs can use simple computer or paper-based mental rotation training instead of more expensive materials to enhance certain aspects of surgical performance of trainees.     

Co-speech iconic gestures and visuo-spatial working memory

Three experiments tested the role of verbal versus visuo-spatial working memory in the comprehension of co-speech iconic gestures. In Experiment 1, participants viewed congruent discourse primes in which the speaker's gestures matched the information conveyed by his speech, and incongruent ones in which the semantic content of the speaker's gestures diverged from that in his speech. Discourse primes were followed by picture probes that participants judged as being either related or unrelated to the preceding clip. Performance on this picture probe classification task was faster and more accurate after congruent than incongruent discourse primes. The effect of discourse congruency on response times was linearly related to measures of visuo-spatial, but not verbal, working memory capacity, as participants with greater visuo-spatial WM capacity benefited more from congruent gestures. In Experiments 2 and 3, participants performed the same picture probe classification task under conditions of high and low loads on concurrent visuo-spatial (Experiment 2) and verbal (Experiment 3) memory tasks. Effects of discourse congruency and verbal WM load were additive, while effects of discourse congruency and visuo-spatial WM load were interactive. Results suggest that congruent co-speech gestures facilitate multi-modal language comprehension, and indicate an important role for visuo-spatial WM in these speech–gesture integration processes.     

A lateralization of function approach to sex differences in spatial ability: a reexamination

The current study assessed the lateralization of function hypothesis (Rilea, S. L., Roskos-Ewoldsen, B., & Boles, D. (2004). Sex differences in spatial ability: A lateralization of function approach. Brain and Cognition, 56, 332–343) which suggested that it was the interaction of brain organization and the type of spatial task that led to sex differences in spatial ability. A second purpose was to evaluate explanations for their unexpected findings on the mental rotation task. In Experiment 1, participants completed the Water Level, Paper Folding, and mental rotation tasks (using an object-based or self-based perspective), presented bilaterally. Sex differences were only observed on the Water Level Task; a right hemisphere advantage was observed on Water Level and mental rotation tasks. In Experiment 2, a human stick figure or a polygon was mentally rotated. Men outperformed women when rotating polygons, but not when rotating stick figures. Men demonstrated a right hemisphere advantage when rotating polygons; women showed no hemisphere differences for either stimulus. Thus, hemisphere processing, task complexity, and stimulus type may influence performance for men and women across different spatial measures.