Susan Wagner Cook

Gesturing makes learning last

The gestures children spontaneously produce when explaining a task predict whether they will subsequently learn that task. Why? Gesture might simply reflect a childs readiness to learn a particular task. Alternatively, gesture might itself play a role in learning the task. To investigate these alternatives, we experimentally manipulated childrens gesture during instruction in a new mathematical concept. We found that requiring children to gesture while learning the new concept helped them retain the knowledge they had gained during instruction. In contrast, requiring children to speak, but not gesture, while learning the concept had no effect on solidifying learning. Gesturing can thus play a causal role in learning, perhaps by giving learners an alternative, embodied way of representing new ideas. We may be able to improve childrens learning just by encouraging them to move their hands.

Gesturing Gives Children New Ideas About Math

How does gesturing help children learn? Gesturing might encourage children to extract meaning implicit in their hand movements. If so, children should be sensitive to the particular movements they produce and learn accordingly. Alternatively, all that may matter is that children move their hands. If so, they should learn regardless of which movements they produce. To investigate these alternatives, we manipulated gesturing during a math lesson. We found that children required to produce correct gestures learned more than children required to produce partially correct gestures, who learned more than children required to produce no gestures. This effect was mediated by whether children took information conveyed solely in their gestures and added it to their speech. The findings suggest that body movements are involved not only in processing old ideas, but also in creating new ones. We may be able to lay foundations for new knowledge simply by telling learners how to move their hands.

Making Children Gesture Brings Out Implicit Knowledge and Leads to Learning

Speakers routinely gesture with their hands when they talk, and those gestures often convey information not found anywhere in their speech. This information is typically not consciously accessible, yet it provides an early sign that the speaker is ready to learn a particular task (S. Goldin-Meadow, 2003). In this sense, the unwitting gestures that speakers produce reveal their implicit knowledge. But what if a learner was forced to gesture? Would those elicited gestures also reveal implicit knowledge and, in so doing, enhance learning? To address these questions, the authors told children to gesture while explaining their solutions to novel math problems and examined the effect of this manipulation on the expression of implicit knowledge in gesture and on learning. The authors found that, when told to gesture, children who were unable to solve the math problems often added new and correct problem-solving strategies, expressed only in gesture, to their repertoires. The authors also found that when these children were given instruction on the math problems later, they were more likely to succeed on the problems than children told not to gesture. Telling children to gesture thus encourages them to convey previously unexpressed, implicit ideas, which, in turn, makes them receptive to instruction that leads to learning.

The Role of Gesture in Learning: Do Children Use Their Hands to Change Their Minds?

Adding gesture to spoken instructions makes those instructions more effective. The question we ask here is why. A group of 49 third and fourth grade children were given instruction in mathematical equivalence with gesture or without it. Children given instruction that included a correct problem-solving strategy in gesture were significantly more likely to produce that strategy in their own gestures during the same instruction period than children not exposed to the strategy in gesture. Those children were then significantly more likely to succeed on a posttest than children who did not produce the strategy in gesture. Gesture during instruction encourages children to produce gestures of their own, which, in turn, leads to learning. Children may be able to use their hands to change their minds.

Consolidation and Transfer of Learning After Observing Hand Gesture

Children who observe gesture while learning mathematics perform better than children who do not, when tested immediately after training. How does observing gesture influence learning over time? Children (n = 184, ages = 7-10) were instructed with a videotaped lesson on mathematical equivalence and tested immediately after training and 24 hr later. The lesson either included speech and gesture or only speech. Children who saw gesture performed better overall and performance improved after 24 hr. Children who only heard speech did not improve after the delay. The gesture group also showed stronger transfer to different problem types. These findings suggest that gesture enhances learning of abstract concepts and affects how learning is consolidated over time.

Gestures, but not meaningless movements, lighten working memory load when explaining math

Gesturing is ubiquitous in communication and serves an important function for listeners, who are able to glean meaningful information from the gestures they see. But gesturing also functions for speakers, whose own gestures reduce demands on their working memory. Here we ask whether gestures beneficial effects on working memory stem from its properties as a rhythmic movement, or as a vehicle for representing meaning. We asked speakers to remember letters while explaining their solutions to math problems and producing varying types of movements. Speakers recalled significantly more letters when producing movements that coordinated with the meaning of the accompanying speech, i.e., when gesturing, than when producing meaningless movements or no movement. The beneficial effects that accrue to speakers when gesturing thus seem to stem not merely from the fact that their hands are moving, but from the fact that their hands are moving in coordination with the content of speech.

Pronuclear formation in starfish eggs inseminated at different stages of meiotic maturation: Correlation of sperm nuclear transformations and activity of the maternal chromatin

Changes in sperm nuclei incorporated into starfish, Asterina miniata, eggs inseminated at different stages of meiosis have been correlated with the progression of meiotic maturation. A single, uniform rate of sperm expansion characterized eggs inseminated at the completion of meiosis. In oocytes inseminated at metaphase I and II the sperm nucleus underwent an initial expansion at a rate comparable to that seen in eggs inseminated at the pronuclear stage. However, in oocytes inseminated at metaphase I, the sperm nucleus ceased expanding by meiosis II and condensed into chromosomes which persisted until the completion of meiotic maturation. Concomitant with the formation and expansion of the female pronucleus, sperm chromatin of oocytes inseminated at metaphase I enlarged and developed into male pronuclei. Condensation of the initially expanded sperm nucleus in oocytes inseminated at metaphase II was not observed. Instead, the enlarged sperm nucleus underwent a dramatic increase in expansion commensurate with that taking place with the maternal chromatin to form a female pronucleus. Fusion of the relatively large female pronucleus and a much smaller male pronucleus was observed in eggs fertilized at the completion of meiotic maturation. In oocytes inseminated at metaphase I and II, the male and female pronuclei, which were similar in size, migrated into juxtaposition, and as separate structures underwent prophase. The chromosomes in each pronucleus condensed, intermixed, and became aligned on the metaphase palate of the mitotic spindle in preparation for the first cleavage division. These observations demonstrate that the time of insemination with respect to the stage of meiotic maturation has a significant effect on sperm nuclear transformations and pronuclear morphogenesis.

Hippocampal declarative memory supports gesture production: Evidence from amnesia.

Spontaneous co-speech hand gestures provide a visuospatial representation of what is being communicated in spoken language. Although it is clear that gestures emerge from representations in memory for what is being communicated (De Ruiter, 1998; Wesp, Hesse, Keutmann, & Wheaton, 2001), the mechanism supporting the relationship between gesture and memory is unknown. Current theories of gesture production posit that action - supported by motor areas of the brain - is key in determining whether gestures are produced. We propose that when and how gestures are produced is determined in part by hippocampally-mediated declarative memory. We examined the speech and gesture of healthy older adults and of memory-impaired patients with hippocampal amnesia during four discourse tasks that required accessing episodes and information from the remote past. Consistent with previous reports of impoverished spoken language in patients with hippocampal amnesia, we predicted that these patients, who have difficulty generating multifaceted declarative memory representations, may in turn have impoverished gesture production. We found that patients gestured less overall relative to healthy comparison participants, and that this was particularly evident in tasks that may rely more heavily on declarative memory. Thus, gestures do not just emerge from the motor representation activated for speaking, but are also sensitive to the representation available in hippocampal declarative memory, suggesting a direct link between memory and gesture production.

Gestures make memories, but what kind? Patients with impaired procedural memory display disruptions in gesture production and comprehension

Hand gesture, a ubiquitous feature of human interaction, facilitates communication. Gesture also facilitates new learning, benefiting speakers and listeners alike. Thus, gestures must impact cognition beyond simply supporting the expression of already-formed ideas. However, the cognitive and neural mechanisms supporting the effects of gesture on learning and memory are largely unknown. We hypothesized that gestures ability to drive new learning is supported by procedural memory and that procedural memory deficits will disrupt gesture production and comprehension. We tested this proposal in patients with intact declarative memory, but impaired procedural memory as a consequence of Parkinsons disease (PD), and healthy comparison participants with intact declarative and procedural memory. In separate experiments, we manipulated the gestures participants saw and produced in a Tower of Hanoi (TOH) paradigm. In the first experiment, participants solved the task either on a physical board, requiring high arching movements to manipulate the discs from peg to peg, or on a computer, requiring only flat, sideways movements of the mouse. When explaining the task, healthy participants with intact procedural memory displayed evidence of their previous experience in their gestures, producing higher, more arching hand gestures after solving on a physical board, and smaller, flatter gestures after solving on a computer. In the second experiment, healthy participants who saw high arching hand gestures in an explanation prior to solving the task subsequently moved the mouse with significantly higher curvature than those who saw smaller, flatter gestures prior to solving the task. These patterns were absent in both gesture production and comprehension experiments in patients with procedural memory impairment. These findings suggest that the procedural memory system supports the ability of gesture to drive new learning.

Gamete Interactions and the Initiation of Egg Activation in Sea Urchins

The earliest perceivable response of echinoid eggs to the fertilizing sperm is a transient depolarization, the activation or fertilization potential (Steinhardt et al., 1971; Jaffe, 1976; Chambers and de Armendi, 1979). This change in electrical activity involves the appearance of sperm associated ion channels, which depolarize the plasma membrane, as well as the opening of voltage-dependent calcium channels (Chambers and de Armendi, 1979). These changes constitute Phase 1 (Lynn et al., 1988; Chambers, 1989). In voltage clamped eggs, sperm which induce Phase 1 either enter or fail to enter the egg. If sperm penetration occurs, the inward current of Phase 1, initiating Phase 2, continues to increase; if sperm penetration fails to occur the inward current is abruptly severed. During Phase 2 a large, rapid and transient increase in intracellular free calcium (Steinhardt and Epel, 1974; Steinhardt et al., 1977; Whitaker and Steinhardt, 1982; Jaffe, 1983) propagates in the form of a wave from the point of gamete interaction to the opposite pole of the egg (Eisen et al., 1984; Swan and Whitaker, 1986; Yoshimoto et al., 1987). This wave of increased intracellular calcium is initiated following a latent period (Phase 1) of approximately 12 sec and stimulates the egg from its quiescent state to proliferation and embryogenesis (Chambers, 1989).