Animacy and propulsion in infancy: Tracking,waving and reaching to self-propelled and induced moving objects

Infants from 16 to 20 weeks were videotaped while being presented with objects traversing a 60 cm distance. Four conditions were tested: (1) induced movement, holding the object; (2) induced movement, pushing the object; (3) self-propelled mechanical movement, object moving by an internal clockwork; (4) self-propelled biological movement, animate object moving by internal impulse. In tracking, the self-propelled but inanimate and mechanically moving object with the more straight and predictable trajectory attracted most visual attention. In arm movements, the self-propelled but relatively unpredictably moving animate object was reliably distinguished from inanimate objects. It appeared that the action system was less dependent on objects taking a straight and predictable course. Emerging with the onset of goal-directed reaches, the distinction of an internal locus of propulsion in objects was overriding the nearly exclusive response towards animacy occurring in waving. Thus, a distinction of different types of object motion could be found in infants’ developing action system.     

Infants' concept of animacy

Nine- and 12-month-old infants' concept of animacy was investigated by exposing them to autonomous motion by an animate and by an inanimate object in a series of three experiments. In the first experiment, increases in negative affect in comparison to a baseline condition were taken to indicate that children considered an event to be anomalous. Results showed that 12-month-old infants consider self-propulsion by a small robot to be anomalous, but not self-propulsion by a human stranger. Experiment 2 indicated that 9- and 12-month-old infants expressed similar affective reactions when the robot's motion was contingent on verbal commands given by the mother, suggesting that these children are aware that it is not appropriate for an inanimate object's movements to be contingent on events occuring at a distance. The third experiment was designed to rule out the possibility that the infants' reactions in Experiment 2 were a function of the incongruity of the mother's behavior rather than due to the violation of the infant's concept of animacy. In this experiment, 12-month-olds' levels of attentiveness are increased when the robot obeyed verbal commands but not when a human stranger did so. These results suggest that infants discriminate animate from inanimate objects on the basis of motion cues by the age of 9 months.     

Infants’ ability to associate motion paths with object kinds

The goal of the present research was to examine whether infants associate different paths of motion with animate beings and inanimate objects. An infant-controlled habituation procedure was used to examine 10–20-month-old infants’ ability to associate a non-linear motion path (jumping) with animals and a linear (rebounding) motion path with vehicles (Experiment 1) and furniture (Experiment 2). During the habituation phase, infants saw a dog jumping over a barrier and either a vehicle or a piece of furniture rebounding off the barrier. In the test phase, infants looked longer when another inanimate object jumped rather than rebounded, but showed no such differential looking in the case of another animate object. The ability to restrict the animate motion path of jumping to animate beings was present by 10 months of age. The present findings support the hypothesis that motion path is associated with the animate–inanimate distinction early in infancy.     

Patterns of 4-month-old infant responses to hidden silent and sounding people and objects

Responses of 4-month-old infants to hidden people and objects were investigated with equated task demands. Twenty-one 4-month-old infants were administered a combined task, in which they were shown a sounding stimulus that continued to sound after hiding, an auditory task, in which sound was the only source of information about the position of the object in space, and a vision task, in which a silent stimulus was shown to the infants prior to hiding. Five infant behaviours were coded: reaching, gazing, body movements, vocalizations and smiles. The infants reached significantly more for hidden objects than for people, to whom they vocalized instead. They further smiled, and moved their bodies more towards their invisible mother than to the other stimuli. Thus infants responded differentially to people and objects whether the stimuli were soundless (so that there was no cue to their presence) or not. This suggested that infants appreciated (a) that an object had been hidden; (b) this object was either animate or inanimate; and (c) different procedures were appropriate for the retrieval of, or for interacting with animate and inanimate objects. Discussion centres on the underlying representational system that allows for such appreciation.     

A nonhuman primate's expectations about object motion and destination: The importance of self-propelled movement and animacy

Human infants have considerable understanding of why objects move and what causes them to take one trajectory over another. Here, we explore the possibility that this capacity is shared with other nonhumans and present results from preferential looking time tests with a New World monkey, the cotton-top tamarin. Experiments examined whether individuals form different expectations about an object's potential capacity to change locations. Test objects were: 1) self-propelled, moving, animate; 2) self-propelled, moving, inanimate; 3) non-self-propelled, moving due to an external agent, inanimate; 4) non-self-propelled, motionless, inanimate. When category 1 objects, either a live mouse or frog, emerged from behind an occluder in a novel location, this did not affect looking time; subjects appeared to expect such changes. In contrast, when the other objects emerged in a novel location following occlusion from view, subjects looked longer than when the object emerged in the location seen prior to occlusion; such locational changes were apparently not expected. Some feature other than self-propelled motion accounts for the tamarins’ looking time responses and at least one candidate feature is whether the object is animate or inanimate.     

The infant's concept of agency: the distinction between social and nonsocial objects

The primary purpose of this study was to examine young infants' discrimination between the abilities of social and nonsocial objects to serve as agents. Thirty-one infants between 8 months and 8 days old and 14 months and 19 days old were studied. The children's communicative skills were evaluated through frustration episodes in which a toy was taken away in order to elicit communicative behaviors toward the mother. Visual fixation time was compared for events in which an inanimate object moved independently and events in which a human being was the agent. Analysis of the magnitude of decrease of attending responses revealed that the older infants took longer to process anomalous events, whereas the younger infants manifested more interest for events in which an animate being played the role of agent. The findings suggest that infants can distinguish between the causal powers of social and nonsocial objects by the end of the first year.     

Effect of target animacy on hand preference in Sichuan snub-nosed monkeys (<Emphasis Type="Italic">Rhinopithecus roxellana</Emphasis>)

Twenty-eight captive Sichuan snub-nosed monkeys (Rhinopithecus roxellana) were involved in the current study. Many individuals showed handedness, with a modest tendency toward left-hand use especially for animate targets, although no group-level handedness was found. There was no significant gender difference in the direction and strength of hand preference for both targets. Females showed a significantly higher overall rate of actions toward animate targets than inanimate targets for both hands, whereas males displayed almost the reversed pattern. There were no significant interactions between lateral hand use and target animacy for either males or females. Most individuals showed rightward or leftward laterality shift trends between inanimate and animate targets. These findings to some extent support the existence of a potential trend concerning a categorical neural distinction between targets demanding functional manipulation (inanimate objects) and those demanding social manipulation (animate objects), even though specialized hand preference based on target animacy has not been fully established in this arboreal Old World monkey species.     

Are human bodies represented differently from other objects? Experience shapes object representations

This study investigated the cognitive organization of the human body representation and its relationship to other object representations. It addressed whether (1) all objects and their parts were organized similarly, (2) animate objects and their parts were organized differently from inanimate objects and their parts, and (3) the human body was organized differently from all other objects. The relations among the parts of three exemplar objects (human body, bear, and bicycle) were examined. Participants performed a series of sorting tasks using stimulus cards illustrating various part and part combinations of these objects; the cards were constructed so that the same strategies could be used to categorize all three objects. Dissimilarity data were analysed using multidimensional scaling techniques. Results indicated that the human body was organized differently from the other objects, and that categorization did not follow the animate–inanimate distinction. Although animate objects were represented more on their visual characteristics and inanimate objects were represented more on functional characteristics, the human body was represented on its ability to perform actions. Representations of the other objects suggested that their organization was embodied in that they appear to be shaped by how the human body interacts, or doesn't interact, with the object.     

Infant's Inductive Generalization of Bodily,Motion, and Sensory Properties to Animals and People

It has been proposed that infants can form global categories such as animate and inanimate objects (Mandler, 2004). The inductive generalization paradigm was used to examine inferences made by infants about the bodily, motion, and sensory capabilities of people and animals. In Experiment 1, 14-month-old infants generalized bodily and sensory properties from dogs to cats and vice-versa. In Experiment 2, 16- and 20-month-olds generalized motion and sensory properties modeled with a person more often to mammals than to vehicles. Findings from Experiment 3 indicated that motion properties are generalized broadly to people and mammals but that by 20 months of age, infants may be beginning to attribute sensory properties preferentially to people more than to animals.     

The animacy advantage for free-recall performance is not attributable to greater mental arousal

People often demonstrate better memory for animate concepts (e.g., lion and sailor) than for inanimate concepts (e.g., hammer and mountain). Researchers have attributed this effect to an adaptive memory mechanism that favours information relevant for survival, including information about living things. In the present experiment, we examined the hypothesis that people demonstrate better free-recall performance for animate than inanimate words because animate words tend to be associated with greater mental arousal than inanimate words, a factor that was not controlled for in previous experiments on this topic. To this end, we matched animate and inanimate word lists on mental arousal (and several other factors), and compared participants’ free-recall performance for the two word types. We were able to replicate past findings that participants’ free-recall of animate words exceeds their free-recall of inanimate words, but we found no support for the possibility that the effect stems from differences in mental arousal between animate and inanimate concepts, as this effect maintained even when the word lists were matched on mental arousal. The present results therefore indicate that mental arousal cannot explain the effects of animacy on free-recall performance.     

4~7岁儿童依据对繁殖的朴素理解区分植物和非生物的认知发展

以152名4~7岁儿童为被试,采用访谈和判断选择任务探查他们对植物繁殖的认知。结果发现,①4~7岁儿童对植物繁殖的认知可分为不理解、部分理解和确切理解三种水平,儿童在入学后7岁能依据对植物繁殖的朴素理解区分植物与非生物;②通过降低材料难度和任务形式要求的难度,可以有效地发掘年幼儿童的认知潜能,即大部分6岁学前儿童就能够理解植物繁殖;③任务难度的改变对处于部分理解水平的5、6儿童影响更为显著：使他们在选择任务上的认知成绩优于访谈任务,对有明显果实和种子植物的认知优于无明显果实和种子植物的认知     

Conservation of Physical Attributes of Animate and Inanimate Objects

Children's (N = 83 boys and girls in kindergarten and first grade) responses to a series of conservation tasks (number, length, mass, weight) which had animate and inanimate referent objects, in two experiments, showed significant differences in the proportions of conservation between animate and inanimate objects. Physical attributes were conserved more easily with inanimate objects than with animate objects, and significant conservation differences between various animate objects were found also.     

Children's reasoning about physics within and across ontological kinds

Reasoning about seven physics principles within and across ontological kinds was examined among 188 5- and 7-year-olds and 59 adults. Individuals in all age groups tended to appropriately generalize what they learned across ontological kinds. However, children also showed sensitivity to ontological kind in their projections: when learning principles with reference to people they were more likely to assume that the principles apply to another person than to an inanimate object, and when learning with reference to an inanimate object they were more likely to assume that the principles apply to another inanimate object than to a person. Five-year-olds, but not 7-year-olds, projected concepts learned about people to a greater extent than principles learned about inanimate objects, closely paralleling the findings of Carey for the biological domain (Carey, S. (1985). Conceptual change in childhood. Cambridge, MA: MIT Press). Results from a separate sample of 22 5-year-olds suggest that the primary findings cannot be explained by response perseveration. The present findings indicate that children understand physics principles that apply to both animate and inanimate objects, but distinguish between these ontological kinds.     

Privileged detection of conspecifics: Evidence from inversion effects during continuous flash suppression

The rapid visual detection of other people in our environment is an important first step in social cognition. Here we provide evidence for selective sensitivity of the human visual system to upright depictions of conspecifics. In a series of seven experiments, we assessed the impact of stimulus inversion on the detection of person silhouettes, headless bodies, faces and other objects from a wide range of animate and inanimate control categories. We used continuous flash suppression (CFS), a variant of binocular rivalry, to render stimuli invisible at the beginning of each trial and measured the time upright and inverted stimuli needed to overcome such interocular suppression. Inversion strongly interfered with access to awareness for human faces, headless human bodies, person silhouettes, and even highly variable body postures, while suppression durations for control objects were not (inanimate objects) or only mildly (animal faces and bodies) affected by inversion. Furthermore, inversion effects were eliminated when the normal body configuration was distorted. The absence of strong inversion effects in a binocular control condition not involving interocular suppression suggests that non-conscious mechanisms mediated the effect of inversion on body and face detection during CFS. These results indicate that perceptual mechanisms that govern access to visual awareness are highly sensitive to the presence of conspecifics.     

Young infants’ reasoning about physical events involving inert and self-propelled objects

The present research examined whether 5- to 6.5-month-old infants would hold different expectations about various physical events involving a box after receiving evidence that it was either inert or self-propelled. Infants were surprised if the inert but not the self-propelled box: reversed direction spontaneously (Experiment 1); remained stationary when hit or pulled (Experiments 3 and 3A); remained stable when released in midair or with inadequate support from a platform (Experiment 4); or disappeared when briefly hidden by one of two adjacent screens (the second screen provided the self-propelled box with an alternative hiding place; Experiment 5). On the other hand, infants were surprised if the inert or the self-propelled box appeared to pass through an obstacle (Experiment 2) or disappeared when briefly hidden by a single screen (Experiment 5). The present results indicate that infants as young as 5 months of age distinguish between inert and self-propelled objects and hold different expectations for physical events involving these objects, even when incidental differences between the objects are controlled. These findings are consistent with the proposal by Gelman, R. (1990). First principles organize attention to and learning about relevant data: Number and the animate–inanimate distinction as examples. Cognitive Science, 14, 79–106, Leslie, A. M. (1994). ToMM, ToBY, and Agency: Core architecture and domain specificity. In L. A. Hirschfeld & S. A. Gelman (Eds.), Mapping the mind: Domain specificity in cognition and culture (pp. 119–148). New York: Cambridge University Press, and others that infants endow self-propelled objects with an internal source of energy. Possible links between infants’ concepts of self-propelled object, agent, and animal are also discussed.     

Why is a verb like an inanimate object? Grammatical category and semantic category deficits

Semantic category effects, such as difficulties in naming animate things relative to inanimate objects, have been explained in terms of the relative weightings of perceptual and functional features within the semantic representations of these concepts. We argue that grammatical category deficits, such as difficulties in naming nouns relative to verbs, can be explained within the same framework. We hypothesize that verb concepts are richer in functional than sensory features and present a model of the semantic representations of animate nouns, inanimate nouns, and verbs. The model demonstrates that sensory feature damage results in a deficit for naming living things but spares verb naming, and functional feature damage results in a deficit for naming inanimate objects and verbs. We then report the assessment results of two patient groups. In accordance with the model's predictions, the "verb spared" patients were consistently worse at naming living things than inanimate objects, and their definitions of both living and nonliving items were lacking in sensory information. We conclude that damage to sensory features in semantic representations causes difficulties in naming concrete nouns relative to action verbs, and within the grammatical category of nouns, animate items will be more severely affected. Imageability was shown to be a strong predictor of naming performance in the "verb deficit" patients, and when this variable was controlled no class effect remained. Production of definitions revealed no differential damage to sensory or functional features, and no consistent effect of animacy in naming was shown. While the model suggests that verb deficits might occur in patients for whom functional features are damaged relative to sensory features, we conclude that the "verb deficit" shown in our patients (and potentially in many previously reported cases) was an artifact of the lower imageability of verbs in confrontation naming tasks.     

Development of categorization in infancy: advancing forward to the animate/inanimate level

Three experiments are reported on the development of object categorization skills during the second year of life. Experiment 1 examined whether 14- and 18-month-old infants were capable of performing categorization at the animate/inanimate (A/I) level using a sequential touching task. The 18-month-olds were significantly above chance and the 14-month-olds were also approaching above-chance significance, which is the highest level of inclusiveness ever tested in infancy. In Experiments 2 and 3, 14-month-old infants participated in a sequential touching task in which the part features of animate and inanimate objects were modified, allowing for a test of partonomic (i.e., legs and wheels) vs. taxonomic (i.e., animates and inanimates) categorization. Infants did not favor partonomic categorization, suggesting that A/I categories are not formed solely based on object parts such as legs and wheels.     

Infant perception of causal motion produced by humans and inanimate objects

Both the movements of people and inanimate objects are intimately bound up with physical causality. Furthermore, in contrast to object movements, causal relationships between limb movements controlled by humans and their body displacements uniquely reflect agency and goal-directed actions in support of social causality. To investigate the development of sensitivity to causal movements, we examined the looking behavior of infants between 9 and 18 months of age when viewing movements of humans and objects. We also investigated whether individual differences in gender and gross motor functions may impact the development of the visual preferences for causal movements. In Experiment 1, infants were presented with walking stimuli showing either normal body translation or a “moonwalk” that reversed the horizontal motion of body translations. In Experiment 2, infants were presented with unperformable actions beyond infants’ gross motor functions (i.e., long jump) either with or without ecologically valid body displacement. In Experiment 3, infants were presented with rolling movements of inanimate objects that either complied with or violated physical causality. We found that female infants showed longer looking times to normal walking stimuli than to moonwalk stimuli, but did not differ in their looking time to movements of inanimate objects and unperformable actions. In contrast, male infants did not show sensitivity to causal movement for either category. Additionally, female infants looked longer at social stimuli of human actions than male infants. Under the tested circumstances, our findings indicate that female infants have developed a sensitivity to causal consistency between limb movements and body translations of biological motion, only for actions with previous visual and motor exposures, and demonstrate a preference toward social information.     

Effects of face and inanimate-object contexts on stimulus–response compatibility

Prior studies have shown that a left–right spatial compatibility effect occurs for vertically oriented stimuli relative to a background context of a face rotated 90° clockwise or counterclockwise from upright. For stimuli presented at the location of the eyes, the mapping of the right eye to a right response and the left eye to a left response, as would be viewed by the participant, yields better performance than does the opposite mapping. An issue of current interest in social cognition is whether animate objects are processed differently from inanimate ones. We investigated this issue in two experiments in which we compared the compatibility effects obtained with inanimate objects to those obtained with animate, face stimuli. The results showed left–right compatibility effects from the participant’s perspective for vehicles and faces from frontal and profile views, as well as for a road sign. Our findings indicate that coding of stimulus location relative to an external frame of reference is not restricted to face backgrounds.     

Mapping Words to the World in Infancy: Infants' Expectations for Count Nouns and Adjectives

Three experimentsdocumentthat 14-month-old infants'construal of objects (e.g., purple animals) is influenced by naming, that they can distinguish between the grammatical form noun and adjective, and that they treat this distinction as relevant to meaning. In each experiment, infants extended novel nouns (e.g., "This one is a blicket") specifically to object categories (e.g., animal), and not to object properties (e.g., purple things). This robust noun-category link is related to grammatical form and not to surface differences in the presentation of novelwords (Experiment 3). Infants'extensions of novel adjectives (e.g., "This one is blickish") were more fragile: They extended adjectives specifically to object properties when the property was color (Experiment 1), but revealed a less precise mapping when the property was texture (Experiment 2). These results reveal that by 14 months, infants distinguish between grammatical forms and utilize these distinctions in determining the meaning of novel words.