Spatiotemporal Configuration Research Articles

The Acoustic Codes: How Animal Sign Processes Create Sound-Topes and Consortia via Conflict Avoidance

In this essay we argue for the possibility to describe the co-presence of species in a community as a consortium built by acoustic codes, using mainly the examples of bird choruses. In this particular case, the consortium is maintained via the sound-tope that different bird species create by singing in a chorus. More generally, the formation of acoustic codes as well as cohesive communicative systems (the consortia) can be seen as a result of plastic adaptational behaviour of the specimen who can solve and avoid conflicts both with conspecifics and with other species in the vicinity. Thus, sign-relations appear to resolve potential conflicts, and as a foundation for symbiotic aggregations. The spatio-temporal configuration of consortia—their chronotope—includes several eco-fields as respective to different functions of the participating organisms. Biological study is combined with a semiotic approach that, as we suggest, should be more often used together to effectively describe ecological processes.

Seismicity patterns along the Ecuadorian subduction zone: new constraints from earthquake location in a 3-D a priori velocity model

To improve earthquake location, we create a 3-D a priori P-wave velocity model (3-DVM) that approximates the large velocity variations of the Ecuadorian subduction system. The 3-DVM is constructed from the integration of geophysical and geological data that depend on the structural geometry and velocity properties of the crust and the upper mantle. In addition, specific station selection is carried out to compensate for the high station density on the Andean Chain. 3-D synthetic experiments are then designed to evaluate the network capacity to recover the event position using only P arrivals and the MAXI technique. Three synthetic earthquake location experiments are proposed: (1) noise-free and (2) noisy arrivals used in the 3-DVM, and (3) noise-free arrivals used in a 1-DVM. Synthetic results indicate that, under the best conditions (exact arrival data set and 3-DVM), the spatiotemporal configuration of the Ecuadorian network can accurately locate 70 per cent of events in the frontal part of the subduction zone (average azimuthal gap is 289° ± 44°). Noisy P arrivals (up to ± 0.3 s) can accurately located 50 per cent of earthquakes. Processing earthquake location within a 1-DVM almost never allows accurate hypocentre position for offshore earthquakes (15 per cent), which highlights the role of using a 3-DVM in subduction zone. For the application to real data, the seismicity distribution from the 3-D-MAXI catalogue is also compared to the determinations obtained in a 1-D-layered VM. In addition to good-quality location uncertainties, the clustering and the depth distribution confirm the 3-D-MAXI catalogue reliability. The pattern of the seismicity distribution (a 13 yr record during the inter-seismic period of the seismic cycle) is compared to the pattern of rupture zone and asperity of the Mw = 7.9 1942 and the Mw = 7.7 1958 events (the Mw = 8.8 1906 asperity patch is not defined). We observe that the nucleation of 1942, 1958 and 1906 events coincides with areas of positive Simple Bouguer anomalies and areas where marine terraces are still preserved on the coastal morphology. From north to south: (1) the 1958 rupture zone is almost aseismic and is attributed to a zone of high coupling; (2) south of the Galera alignment (perpendicular to the trench), the 1942 rupture zone presents moderate seismicity, deeper on the seismogenic interplate zone, and abutting on the Jama cluster (to the south). This cluster is facing the Cabo Pasado cap and positive Bouguer anomalies on the overriding margin. We suspect that this cluster reflects a zone of local asperity (partial coupling). South of the Jama cluster, the spherical aseismic zone in the Bahia area is interpreted as having a low seismic coupling (steady creep motion or slow slip events). We suspect that the site that generated the three M > 7 events (1896, 1956 and 1998) correspond to a small patch of strong coupling. To the south, in the Manta-Puerto Lopez zone, the seismicity is mainly organized in earthquake swarms (1998, 2002, 2005). Although slow slip events have been observed in the area (Vallée et al. submitted), we infer from the coastline shape, the marine terraces and the high positive Bouguer anomalies that the seismicity here might reveal a significant amount of seismic coupling.

Domain-specific perceptual causality in children depends on the spatio-temporal configuration, not motion onset

Humans, even babies, perceive causality when one shape moves briefly and linearly after another. Motion timing is crucial in this and causal impressions disappear with short delays between motions. However, the role of temporal information is more complex: it is both a cue to causality and a factor that constrains processing. It affects ability to distinguish causality from non-causality, and social from mechanical causality. Here we study both issues with 3- to 7-year-olds and adults who saw two computer-animated squares and chose if a picture of mechanical, social or non-causality fit each event best. Prior work fit with the standard view that early in development, the distinction between the social and physical domains depends mainly on whether or not the agents make contact, and that this reflects concern with domain-specific motion onset, in particular, whether the motion is self-initiated or not. The present experiments challenge both parts of this position. In Experiments 1 and 2, we showed that not just spatial, but also animacy and temporal information affect how children distinguish between physical and social causality. In Experiments 3 and 4 we showed that children do not seem to use spatio-temporal information in perceptual causality to make inferences about self- or other-initiated motion onset. Overall, spatial contact may be developmentally primary in domain-specific perceptual causality in that it is processed easily and is dominant over competing cues, but it is not the only cue used early on and it is not used to infer motion onset. Instead, domain-specific causal impressions may be automatic reactions to specific perceptual configurations, with a complex role for temporal information.

The slope of the psychometric function and non-stationarity of thresholds in spatiotemporal contrast vision

The slope of the two-interval, forced-choice psychometric function (e.g. the Weibull parameter, β) provides valuable information about the relationship between contrast sensitivity and signal strength. However, little is known about how or whether β varies with stimulus parameters such as spatiotemporal frequency and stimulus size and shape. A second unresolved issue concerns the best way to estimate the slope of the psychometric function. For example, if an observer is non-stationary (e.g. their threshold drifts between experimental sessions), β will be underestimated if curve fitting is performed after collapsing the data across experimental sessions. We measured psychometric functions for 2 experienced observers for 14 different spatiotemporal configurations of pulsed or flickering grating patches and bars on each of 8days. We found β≈3 to be fairly constant across almost all conditions, consistent with a fixed nonlinear contrast transducer and/or a constant level of intrinsic stimulus uncertainty (e.g. a square law transducer and a low level of intrinsic uncertainty). Our analysis showed that estimating a single β from results averaged over several experimental sessions was slightly more accurate than averaging multiple estimates from several experimental sessions. However, the small levels of non-stationarity (SD≈0.8dB) meant that the difference between the estimates was, in practice, negligible.

An Interactive Mapping Tool to Assess Individual Mobility Patterns in Neighborhood Studies

As their most critical limitation, neighborhood and health studies published to date have not taken into account nonresidential activity places where individuals travel in their daily lives. However, identifying low-mobility populations residing in low-resource environments, assessing cumulative environmental exposures over multiple activity places, and identifying specific activity locations for targeting interventions are important for health promotion. Daily mobility has not been given due consideration in part because of a lack of tools to collect locational information on activity spaces. Thus, the first aim of the current article is to describe VERITAS (Visualization and Evaluation of Route Itineraries, Travel Destinations, and Activity Spaces), an interactive web mapping application that can geolocate individuals' activity places, routes between locations, and relevant areas such as experienced or perceived neighborhoods.The second aim is to formalize the theoretic grounds of a contextual expology as a subdiscipline to better assess the spatiotemporal configuration of environmental exposures. Based on activity place data, various indicators of individual patterns of movement in space (spatial behavior) are described. Successive steps are outlined for elaborating variables of multiplace environmental exposure (collection of raw locational information, selection/exclusion of locational data, defining an exposure area for measurement, and calculation). Travel and activity place network areas are discussed as a relevant construct for environmental exposure assessment. Finally, a note of caution is provided that these measures require careful handling to avoid increasing the magnitude of confounding (selective daily mobility bias).

Towards optimized population control efficiency in space and time: A modelling framework adapted to a colonial waterbird

The double-crested cormorant is a native North American waterbird that recently underwent a dramatic population expansion. Population control efforts in the USA and Canada attempt to mitigate cormorant damages to natural resources and aquaculture. However, there is currently no coordination among the various stakeholders involved in management activities as well as no attempt to optimize population control efficiency. In this paper, we present for the first time a spatially explicit stage-structured metapopulation model parameterized for the cormorant. We developed simulation tools to get insights into the efficiency gain that can be expected from a better planning of management activities in both space and time. A case study is presented, in which we randomized where (on which colonies) and when (which years) a pre-determined amount of management activities would occur on 4 or 8 of 16 active colonies arranged on a 4×4 or 2×8 spatial grid over a period of 8 years, including 2 or 4 management years. We calculated two indices measuring the location of management activities, namely the average date of management years and the average degree of peripherality of colonies undertaking management, together with two indices measuring the resulting correlation of management activities, i.e., the degree of clustering of management activities both in space and time. Different spatio-temporal configurations of management activities generally yielded different metapopulation trajectories. Room for improving management efficiency increased with the intensity of management activities. However, the greatest efficiency gains are to be expected when colonies are far from carrying capacity, while the majority of management operations are undertaken when colonies are near or at carrying capacity. Locations of management activities in space and time appeared more important than resulting spatio-temporal correlations to explain the dispersion of metapopulation trajectories. When colonies were far from their individual carrying capacity, management was more efficient when applied earlier (a consequence of delayed reproductive maturity) and to more central colonies (due to greater immigration). The situation was more complex when colonies were closer to or at carrying capacity. Our modelling framework is flexible enough to allow more complex scenarios to be investigated in the future.

Many Europes: Rethinking multiplicity

This article advances a non-reductionist theorization of Europe as ‘multiplicity’. As an object and category of political reality, Europe is made (and re-made) within specific spatio-temporal configurations. For this reason, the first section argues that Europe should be approached as an instance of ‘historical ontology’. This counters a reductionist tendency to ‘fix’ Europe with definitive political and cultural characteristics or historical trajectories. The second and third sections of the article interrogate a few of the ontological ‘lines of flight’ taken by contemporary Europe. The article discusses Europe’s multiplicity through its fields, imaginaries and ways of being in the world. Such a preliminary sketch of European multiplicity is not meant to be exhaustive. Rather, it suggests a new ethos in the study of European politics that privileges historicism, practice, and Europe’s recursive relationship to the world/globe.

Object-based maintenance of temporal attention in rapid serial visual presentation

The visual system dynamically modulates attention to identify a target embedded in a rapid sequence of nontargets. Typically, the accuracy of target identification increases as the number of preceding items increases and is maintained at this increased level: Known as the attentional awakening phenomenon. In this study, we investigated the temporal characteristics of the visual system that contribute to maintaining attentional state throughout a trial. In Experiment 1, we initially demonstrated that the enhanced state of attention was reset after a gap of 500–1000 ms that was inserted in the sequence. In Experiment 2, we found that the attentional state was maintained when the temporally separated sequences were encapsulated by a continuous sequence of random dots. In the following experiments, we systematically manipulated the spatiotemporal configurations of random dots (or used a different object) and found that the attentional state was maintained as long as the object continuity was maintained.

Mechanisms of direction selectivity in cat primary visual cortex as revealed by visual adaptation.

In contrast to neurons of the lateral geniculate nucleus (LGN), neurons in the primary visual cortex (V1) are selective for the direction of visual motion. Cortical direction selectivity could emerge from the spatiotemporal configuration of inputs from thalamic cells, from intracortical inhibitory interactions, or from a combination of thalamic and intracortical interactions. To distinguish between these possibilities, we studied the effect of adaptation (prolonged visual stimulation) on the direction selectivity of intracellularly recorded cortical neurons. It is known that adaptation selectively reduces the responses of cortical neurons, while largely sparing the afferent LGN input. Adaptation can therefore be used as a tool to dissect the relative contribution of afferent and intracortical interactions to the generation of direction selectivity. In both simple and complex cells, adaptation caused a hyperpolarization of the resting membrane potential (-2.5 mV, simple cells, -0.95 mV complex cells). In simple cells, adaptation in either direction only slightly reduced the visually evoked depolarization; this reduction was similar for preferred and null directions. In complex cells, adaptation strongly reduced visual responses in a direction-dependent manner: the reduction was largest when the stimulus direction matched that of the adapting motion. As a result, adaptation caused changes in the direction selectivity of complex cells: direction selectivity was reduced after preferred direction adaptation and increased after null direction adaptation. Because adaptation in the null direction enhanced direction selectivity rather than reduced it, it seems unlikely that inhibition from the null direction is the primary mechanism for creating direction selectivity.

Monitoring forest plant biodiversity changes and developing conservation strategies: a study from Camili Biosphere Reserve Area in NE Turkey

This study was carried out in forestland of Camili Biosphere Reserve (CBR) area in NE Turkey. It was designed to evaluate the consequences of disturbances on changes in secondary forest succession from 1985 to 2005 for monitoring forest plant biodiversity changes and developing conservation strategies. The successional stages were mapped using Geographic Information System (GIS), Global Positioning System (GPS), aerial photos and high resolution satellite images (IKONOS). The results showed that stable stage decreased about 77.96% over the last 20-year time period. Although 701.6 ha conifer forests existed in competition and reaction stages in 1985, none existed in 2005. In overall, about 33.23% of the area decreased, 42.36% did not change and 24.41% increased in different seral stages. Consequently, 8.83% of the area decreased as a whole to indicate that the forest has been developing from stable to nudation stage, that is to say, retrogressive succession is going on in the area. Forest structure and its relationship with plant biodiversity along with its changes over time were determined using FRAGSTATS. We also investigated spatio-temporal configuration of six secondary forest successional stages and generated structural diversity measures. These measures revealed that the landscape has been fragmented, posing a danger to lose the important components of plant biodiversity. Sustainable management of such degraded forests is of crucial importance for plant biodiversity conservation. In conclusion, the study contributes to the development of a framework for effective conservation of plant biodiversity through plant biodiversity integrated Multiple Use Forest Management (MUFM) plans by using the successional stages and plant biodiversity changes.

From swarm robotics to smart materials

Swarm intelligence refers to the phenomenon of a system of spatially distributed individuals that coordinate their actions in a decentralized and self-organized manner, so as to exhibit complex collective behavior. Such systems tend to have large numbers of individual agents that interact with each other in simple ways. This allows swarm-intelligent systems to be inherently robust and flexible. As these principles are scale-free, systems with these properties can range in size from the nano to the macro scale. Swarm-intelligent systems are common throughout nature. Examples are bacteria colonies, neural networks, social insects, and flocks/herds of vertebrates. In addition, humans have produced a variety of (artificial) swarm systems ranging from swarm-based optimization algorithms to sensor networks, swarms of robots, and smart materials. In each of these natural or artificial systems, populations of agents change their spatiotemporal configuration solely based on the agents’ local interactions with each other and the environment. This special issue on ‘‘Swarm Robotics’’ provides an overview of recent results and trends in this emerging field. Contributions to this special issue range from programming paradigms for swarming systems to specific distributed algorithms and modular robotic systems. The unifying theme of these works is individual simplicity: complex global behavior emerges from purely local interactions and simple local rules. Examples covered in this special issue range from spatial behaviors such as flocking and dispersion, computational behaviors such as shortest-path routing and collective decisions, up to full-body behaviors of modular robot ensembles. In their paper, ‘‘Composable continuous-space programs for robotic swarms’’, Bachrach, Beal, and McLurkin present the functional programming language Proto that allows individual behavior to be described by expressions over a global field. By computing the global field not only from local measurements but also based on data received from other swarm members within the local neighborhood, previous state, and control logic, Proto allows complex swarming behaviors to be composed with highly compact code. Proto code is then compiled into op-codes for the Proto Virtual Machine, which needs to provide abstractions for sensing, actuation, estimation of the geometric relations between neighboring swarm members, and local communication. Algorithms such as shortest-path routing are demonstrated on a swarm of 40 miniature mobile robots, as well as in computer simulations. In their paper, ‘‘Collective decision-making based on social odometry’’, Gutierrez, Campo, Monasterio-Huelin, Magdalena, and Dorigo investigate a novel collective decision-making mechanism using a colony of mobile robots that accomplish a foraging task. The robots are required to establish a path from a central place to the closest of multiple resource sites. To reach a consensus, they make use of social odometry. The latter mechanism enables the robots to estimate the position of resource sites by exchanging and aggregating odometry-based positional information and confidence levels. The collective decisionmaking mechanism is successfully validated by experiment N. Correll (&) Department of Computer Science, University of Colorado at Boulder, 430 UCB, Boulder, CO 80309, USA e-mail: nikolaus.correll@colorado.edu

Mesoproterozoic carbonate systems in the Borden Basin, Nunavut

Existing stratigraphic nomenclature, lithologic descriptions, and geological interpretations for an economically important Mesoproterozoic dolostone in the Milne Inlet Graben, Borden Basin, Nunavut, do not adequately portray its unusual facies or their spatio-temporal configuration. Four new stratigraphic units are introduced to replace this dolostone, formerly known as the Society Cliffs Formation. In the southeastern half of the graben, the Iqqittuq Formation represents a distally steepened ramp that grades northwestward into deep-water mudstone that is indistinguishable from that of the underlying Arctic Bay Formation. The overlying Angmaat Formation represents a rimmed, restricted peritidal platform that grades northwestward across a tepee – cortoid shoal barrier into the unusual, deep-water dolo-laminite of the Nanisivik Formation. Deep-water carbonate mounds up to hundreds of metres thick and kilometres in areal dimensions belong to the Ikpiarjuk Formation; these mounds are geometrically equivalent to upper Arctic Bay Formation mudstone, Iqqittuq Formation outermost ramp, and part of the Nanisivik Formation dolostone. The Iqqittuq, Nanisivik, and Ikpiarjuk formations conformably overlie mudstone of the Arctic Bay Formation. The Angmaat and Nanisivik formations are unconformably overlain by mudstone of the lower Victor Bay Formation. These new, formal, mappable stratigraphic entities were deposited in two time stages, and their three-dimensional configuration depicts an unusual, tectonically influenced basin that was also affected by high-amplitude eustatic cyclicity in shallow water.

Modelling multi-species response to landscape dynamics: mosaic cycles support urban biodiversity

The importance of the spatial as well as the temporal structure of habitat patches for urban biodiversity has been recognised, but rarely quantified. In dynamic environments the rate of habitat destruction and recreation (i.e. the landscape turnover rate), the minimum amount of potential habitat, its spatial configuration as well as the environmental conditions determining habitat quality are crucial factors for species occurrence. We analysed species responses to environmental parameters and to the spatio-temporal configuration of urban brownfield habitats in a multi-species approach (37 plant and 43 insect species). Species presence/absence data and soil parameters, site age, vegetation structure and landscape context were recorded by random stratified sampling at 133 study plots in industrial areas in the city of Bremen (Germany). Based on the field data, we predicted species occurrences by species distribution models using a multi-model inference approach. Predicted species communities were driven by successional age both at the scale of a single building lot and at the landscape scale. Minimum average succession time of brownfield habitats required to support all and especially regionally rare species depended on the proportion of available open space; the larger the potential habitat area the faster the acceptable turnover. Most plant, grasshopper, and leafhopper species modelled could be maintained at an intermediate turnover rate (mean age of 10–15 years) and a proportion of open sites of at least 40%. Our modelling approach provides the opportunity of inferring optimal spatio-temporal landscape configurations for urban conservation management from patch scale species-environment relationships. The results indicate that urban planning should incorporate land use dynamics into the management of urban biodiversity.

Elimination of spiral waves and spatiotemporal chaos by the pulse with a specific spatiotemporal configuration

Spiral waves and spatiotemporal chaos are sometimes harmful and should be controlled. In this paper spiral waves and spatiotemporal chaos are successfully eliminated by the pulse with a very specific spatiotemporal configuration. The excited position D of spiral waves or spatiotemporal chaos is first recorded at an arbitrary time (t0). When the system at the domain D enters a recovering state, the external pulse is injected into the domain. If the intensity and the working time of the pulse are appropriate, spiral waves and spatiotemporal chaos can finally be eliminated because counter-directional waves can be generated by the pulse. There are two advantages in the method. One is that the tip can be quickly eliminated together with the body of spiral wave, and the other is that the injected pulse may be weak and the duration can be very short so that the original system is nearly not affected, which is important for practical applications.

Pattern of settlement and natural chimerism in the colonial urochordate Botryllus schlosseri

Colonies of the cosmopolitan urochordate Botryllus schlosseri that share one or both alleles at a single allorecognition locus (Fu/HC) and come into tissue contacts, may fuse and form a mixed entity, a chimera. Botryllus populations worldwide exhibit unprecedented extensive polymorphism at this locus, a result that restricts fusions to kin encounters. This study aims to compare spatiotemporal configurations in source and introduced B. schlosseri populations, residing on natural and man-made substrata, respectively. By using four microsatellite loci, we tested genetic consanguinity of colonies settled naturally along spatial vectors on both, natural (native populations) and man-made (introduced) substrates. Four populations were studied. Results revealed that B. schlosseri colonies, on both substrate types, assemble in groups of relatives that share similar microsatellite profiles. We suggest that this pattern of settlement promotes the formation of chimeras, which evoke conflicting interactions: cooperation between different somatic cell lines that constitute the colonial soma and competition between germ cells that inhabit the chimera gonads. Under natural conditions, the chimera may allow genetic flexibility that depends on joint genomic fitness of its partners. This is probably one of the life history characteristics that led to the worldwide distribution success of this species.

Role of unstable periodic orbits in phase transitions of coupled map lattices

The thermodynamic formalism for dynamical systems with many degrees of freedom is extended to deal with time averages and fluctuations of some macroscopic quantity along typical orbits, and applied to coupled map lattices exhibiting phase transitions. Thereby, it turns out that a seed of phase transition is embedded as an anomalous distribution of unstable periodic orbits, which appears as a so-called q-phase transition in the spatiotemporal configuration space. This intimate relation between phase transitions and q-phase transitions leads to one natural way of defining transitions and their order in extended chaotic systems. Furthermore, a basis is obtained on which we can treat locally introduced control parameters as macroscopic "temperature" in some cases involved with phase transitions.

AMBULATORY EFFECTS OF BRIEF EXPOSURES TO MAGNETIC FIELDS CHANGING ORTHOGONALLY IN SPACE OVER TIME

In a within-subject design adult male rats were exposed for 15 min once per day or night to one of two patterns of complex magnetic fields (0.5 to 1 micro T) rotated in space once every 2 s or 20 s through each of the three spatial dimensions and then simultaneously through all three dimensions. Open field behavior was then measured for ambulation, defecation, and grooming. The rats displayed about twice the ambulation after when the fields had been present compared to when they had not. The burst-firing field elicited the greatest ambulation when presented during the night whereas the frequency-modulated pattern elicited the greatest ambulation when presented during the day. These results suggest that robust behavioral changes can occur when rats are exposed for 15 min to complex spatiotemporal configurations of weak magnetic fields.

A Population Coding Account for Systematic Variation in Saccadic Dead Time

During movement programming, there is a point in time at which the movement system is committed to executing an action with certain parameters even though new information may render this action obsolete. For saccades programmed to a visual target this period is termed the dead time. Using a double-step paradigm, we examined potential variability in the dead time with variations in overall saccade latency and spatiotemporal configuration of two sequential targets. In experiment 1, we varied overall saccade latency by manipulating the presence or absence of a central fixation point. Despite a large and robust gap effect, decreasing the saccade latency in this way did not alter the dead time. In experiment 2, we varied the separation between the two targets. The dead time increased with separation up to a point and then leveled off. A stochastic accumulator model of the oculomotor decision mechanism accounts comprehensively for our findings. The model predicts a gap effect through changes in baseline activity without producing variations in the dead time. Variations in dead time with separation between the two target locations are a natural consequence of the population coding assumption in the model.

Fashion as viscous knowledge: fashion's role in shaping trans-national garment production

This paper develops a perspective of fashion as a complex, multidimensional form of knowledge and as a technology of garment mass production. It identifies the various modalities of fashion knowledge and characterises their different rates and extents of transmission across space and time in terms of their relative complexity. The paper explores the spatio-temporal configurations of fashion knowledge as it is mobilised in the economy, interrogating the ways in which the uneven viscosity of its different modalities vary with their positioning in geographical space and in relation to other modalities. It then assesses the economic implications of fashion’s place-specific recombinations. These interactions are demonstrated by an examination of the impacts of international fashion trends on fashion garment supplies to the Australian market. The perspective outlined in this paper highlights the inadequacies of the tacit-codified binaries that have dominated geographies of knowledge and shows why the transmission of fashion ideas consolidates rather than diminishes the power of key sites of expert knowledge.

Perceived physical and social causality in animated motions: Spontaneous reports and ratings

Michotte argued that we perceive cause-and-effect, without contributions from reasoning or learning, even in displays of two-dimensional moving shapes. Two studies extend this line of work from perception of mechanical to social causality. We compared verbal reports with structured ratings of causality to gain a better understanding of the extent to which perceptual causality occurs spontaneously or depends on instruction or context. A total of 120 adult observers (72 in the main experiment, 48 in an initial experiment) saw 12 (or 8) different computer animations of shape A moving up to B, which in turn moved away. Animations factorially varied the temporal and spatial relations of the shapes, and whether they moved rigidly or in a non-rigid, animal-like manner. Impressions of social as well as physical causality appeared in both free reports and ratings. Perception of physical causality was stronger than perception of social causality, particularly in free reports. No differences of this nature appear in infants and children, so the asymmetry may reflect learnt knowledge. Physical causality was relatively unspecific initially, but discrimination of causal and delayed control events improved with exposure to multiple events. Experience seems to affect the causal illusion even over a short timeframe; the idea of ‘one-trial causality’ may be somewhat misleading. Regardless of such effects on the absolute level of responses, the different measures showed similar patterns of variation with the spatio-temporal configuration and type of motion. The good fit of ratings and reports validates much recent work in this area.