Visual impressions of active and inanimate resistance to impact from a moving object

ABSTRACT

Images of moving objects presented on computer screens may be perceived as animate or inanimate. A simple hypothesis, consistent with much research evidence, is that objects are perceived as inanimate if there is a visible external contact from another object immediately prior to the onset of motion, and as animate if that is not the case. Evidence is reported that is not consistent with that hypothesis. Objects (targets) moving on contact from another object (launcher) were perceived as actively resisting the impact of the launcher on them if the targets slowed rapidly. Rapid slowing is consistent with the laws of mechanics for objects moving in an environment that offers friction and air resistance. Despite that, ratings of inanimate motion were lower than ratings of active resistance for objects that slowed rapidly. The results are consistent with the hypothesis that there is a perceptual impression of active (animate) resistance that is evoked by the kinematic pattern of rapid slowing from an initial speed after contact from another object.     

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.     

Animacy increases second target reporting in a rapid serial visual presentation task

Attentional blink occurs when two target items, T1 and T2, are presented within brief moments of each other in a series of rapidly presented items and participants fail to report T2. The purpose of the present study was to examine the effect of characteristics of T2 on T2 reporting. Participants (N = 67) completed 4 blocks of 40 trials. Each trial consisted of 15 images, two of which were designated as T1 and T2. T2 was manipulated in three ways: animacy (animate or inanimate), threat (threatening or nonthreatening), and lag (200 ms or 400 ms after T1). The results indicated that more T2s were reported at the longer lag and that animate objects were reported more often than inanimate objects at both lags. Threat did not have a significant effect on T2 reporting although it interacted with lag: threatening objects were reported more frequently than nonthreatening objects at lag 2 but this trend reversed at lag 4. The results were consistent with the animate monitoring hypothesis, which claims that animate objects, because of their importance in ancestral environments, attract attention more easily than inanimate objects. Animate objects appear to capture attention more easily than inanimate objects as second targets in a rapid serial visual presentation task. This result is similar to animacy advantages reported with other attention tasks and with memory tasks.     

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.     

Animacy,perceptual load,and inattentional blindness

Inattentional blindness is the failure to notice unexpected objects in a visual scene while engaging in an attention-demanding task. We examined the effects of animacy and perceptual load on inattentional blindness. Participants searched for a category exemplar under low or high perceptual load. On the last trial, the participants were exposed to an unexpected object that was either animate or inanimate. Unexpected objects were detected more frequently when they were animate rather than inanimate, and more frequently with low than with high perceptual loads. We also measured working memory capacity and found that it predicted the detection of unexpected objects, but only with high perceptual loads. The results are consistent with the animate-monitoring hypothesis, which suggests that animate objects capture attention because of the importance of the detection of animate objects in ancestral hunter–gatherer environments.     

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.     

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.     

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.     

The Role of Animacy in Children's Interpretation of Relative Clauses in English: Evidence From Sentence–Picture Matching and Eye Movements

Subject relative clauses (SRCs) are typically processed more easily than object relative clauses (ORCs), but this difference is diminished by an inanimate head-noun in semantically non-reversible ORCs (“The book that the boy is reading”). In two eye-tracking experiments, we investigated the influence of animacy on online processing of semantically reversible SRCs and ORCs using lexically inanimate items that were perceptually animate due to motion (e.g., “Where is the tractor that the cow is chasing”). In Experiment 1, 48 children (aged 4;5–6;4) and 32 adults listened to sentences that varied in the lexical animacy of the NP1 head-noun (Animate/Inanimate) and relative clause (RC) type (SRC/ORC) with an animate NP2 while viewing two images depicting opposite actions. As expected, inanimate head-nouns facilitated the correct interpretation of ORCs in children; however, online data revealed children were more likely to anticipate an SRC as the RC unfolded when an inanimate head-noun was used, suggesting processing was sensitive to perceptual animacy. In Experiment 2, we repeated our design with inanimate (rather than animate) NP2s (e.g., “where is the tractor that the car is following”) to investigate whether our online findings were due to increased visual surprisal at an inanimate as agent, or to similarity-based interference. We again found greater anticipation for an SRC in the inanimate condition, supporting our surprisal hypothesis. Across the experiments, offline measures show that lexical animacy influenced children's interpretation of ORCs, whereas online measures reveal that as RCs unfolded, children were sensitive to the perceptual animacy of lexically inanimate NPs, which was not reflected in the offline data. Overall measures of syntactic comprehension, inhibitory control, and verbal short-term memory and working memory were not predictive of children's accuracy in RC interpretation, with the exception of a positive correlation with a standardized measure of syntactic comprehension in Experiment 1.     

Target animacy influences chimpanzee handedness

We employed a bottom-up, quantitative method to investigate great ape handedness. Our previous investigation of gorillas (Gorilla gorilla gorilla) demonstrated that contextual information influenced an individual’s handedness toward target objects. Specifically, we found a significant right-hand bias for unimanual actions directed toward inanimate target objects but not for actions directed to animate target objects (Forrester et al. in Anim Cogn 14(6):903–907, 2011). Using the identical methodological technique, we investigated the spontaneous hand actions of nine captive chimpanzees (Pan troglodytes) during naturalistic, spontaneous behavior. We assessed both the frequencies and proportions of lateralized hand actions directed toward animate and inanimate targets employing focal follow video sampling. Like the gorillas, the chimpanzees demonstrated a right-handed bias for actions directed toward inanimate targets, but not toward animate targets. This pattern was evident at the group level and for the majority of subjects at the individual level. We postulate that a right-hand bias for only inanimate targets reflects the left hemisphere’s dominant neural processing capabilities for objects that have functional properties (inanimate objects). We further speculate that a population-level right-hand bias is not a human-unique characteristic, but one that was inherited from a common human-ape ancestor.     

Goal attribution to schematic animals: do 6‐month‐olds perceive biological motion as animate?

Infants are sensitive to biological motion, but do they recognize it as animate? As a first step towards answering this question, two experiments investigated whether 6‐month‐olds selectively attribute goals to shapes moving like animals. We habituated infants to a square moving towards one of two targets. When target locations were switched, infants reacted more to movement towards a new goal than a new location – but only if the square moved non‐rigidly and rhythmically, in a schematic version of bio‐mechanical movement older observers describe as animal‐like ( Michotte, 1963 ). Goal attribution was specific to schematic animal motion: It did not occur if the square moved rigidly with the same rhythm as the animate stimulus, or if the square had the same amount of non‐rigid deformation, but in an inanimate configuration. The data would seem to show that perception of schematic animal motion is linked to a system for psychological reasoning from infancy. This in turn suggests that 6‐month‐olds may already interpret biological motion as animate.     

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.     

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.     

Giving Meaning to Movement: A Developmental Study

Recently, researchers have been investigating the effects of kinematics stimulus properties on pattern perception and recognition. However, the stimulus properties that are used to discriminate animate from inanimate objects have received relatively little attention. Earlier research has indicated that the external movement of artificially generated objects is perceived as animate by observers of all ages. In this investigation, children in Grades 1,4, and 7 and university adults were asked to describe what they saw after viewing computer-generated displays of two circular objects that exhibited variations of external and internal movement. We predicted that observers would incorporate and integrate the salient kinematic properties of the objects in a display into a coherent narrative and that their ability to achieve matches among the properties of objects in a display and the properties of objects described in the narrative would increase with age. Moreover, because of their relative insensitivity to the actual properties of objects in the display, we predicted that younger observers would make more animate attributions for nonmoving objects and fewer animate attributions for moving objects than would older observers. The result supported these predictions.     

Are visual features of a looming or receding object processed in a capacity-free manner?

Numerous experiments have examined whether moving stimuli capture spatial attention but none have sought to determine whether visual features of looming and receding objects are extracted in a capacity-free manner. The current experiment (N = 28) used the task-choice procedure originated by Besner and Care (2003) to examine this possibility. Stimuli were presented in 3D space by manipulating retinal disparity. Results indicate that features of an object are extracted in a capacity-free manner for both looming and receding objects for participants who consciously perceive motion but not for participants who do not consciously perceive motion. These results suggest that the cognitive system is biased to process potentially animate objects, perhaps because of the evolutionary advantage this cognitive ability may provide.     

Chasing perception in domestic cats and dogs

Animal Cognition - Chasing motion is often used to study the perception of inanimate objects as animate. When chasing interaction and independent motions between two agents are displayed...     

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.     

Adaptive memory: Animacy effects persist in paired-associate learning

Recent evidence suggests that animate stimuli are remembered better than matched inanimate stimuli. Two experiments tested whether this animacy effect persists in paired-associate learning of foreign words. Experiment 1 randomly paired Swahili words with matched animate and inanimate English words. Participants were told simply to learn the English “translations” for a later test. Replicating earlier findings using free recall, a strong animacy advantage was found in this cued-recall task. Concerned that the effect might be due to enhanced accessibility of the individual responses (e.g., animates represent a more accessible category), Experiment 2 selected animate and inanimate English words from two more constrained categories (four-legged animals and furniture). Once again, an advantage was found for pairs using animate targets. These results argue against organisational accounts of the animacy effect and potentially have implications for foreign language vocabulary learning.     

Distinct processing for pictures of animals and objects: evidence from eye movements

Many studies have suggested that emotional stimuli orient and engage attention. There is also evidence that animate stimuli, such as those from humans and animals, cause attentional bias. However, categorical and emotional factors are usually mixed, and it is unclear to what extent human context influences attentional allocation. To address this issue, we tracked participants' eye movements while they viewed pictures with animals and inanimate images (i.e., category) as focal objects. These pictures had either negative or neutral emotional valence, and either human body parts or nonhuman parts were near the focal objects (i.e., context). The picture's valence, arousal, position, size, and most of the low-level visual features were matched across categories. The results showed that nonhuman animals were more likely to be attended to and to be attended to for longer times than inanimate objects. The same pattern held for the human contexts (vs. nonhuman contexts). The effects of emotional valence, category, and context interacted. Specifically, in images with a negative valence, focal animals and objects with human context had comparable numbers of gaze fixations and gaze duration. These results highlighted the attentional bias to animate parts of a picture and clarified that the effects of category, valence, and picture context interacted to influence attentional allocation.     

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.