Psychophysiology in games

Psychophysiology is the study of the relationship between psychology and its physiological manifestations. That relationship is of particular importance for both game design and ultimately gameplaying. Players’ psychophysiology offers a gateway towards a better understanding of playing behavior and experience. That knowledge can, in turn, be beneficial for the player as it allows designers to make better games for them; either explicitly by altering the game during play or implicitly during the game design process. This chapter argues for the importance of physiology for the investigation of player affect in games, reviews the current state of the art in sensor technology and outlines the key phases for the application of psychophysiology in games.The work is supported, in part, by the EU-funded FP7 ICT iLearnRWproject (project no: 318803).peer-reviewe

Golden jackal expansion in Europe: A case of mesopredator release triggered by continent-wide wolf persecution?

Top-down suppression by apex predators can limit the abundance and spatial distribution of mesopredators. However, this phenomenon has not been studied over long time periods in human-dominated landscapes, where the strength of this process might be limited. Here, we used a multi-scale approach to analyse interactions between two canids in the human-dominated landscapes of Europe. We tested the hypothesis that the range expansion of golden jackals (Canis aureus) was triggered by intensive persecution and resulting decline of the apex predator, the grey wolf (Canis lupus). To do so, we (1) reviewed literature to reconstruct the historic changes in the distribution and abundance of the two canid species on the continental scale, (2) analysed hunting data patterns for both species in Bulgaria and Serbia, and (3) surveyed jackal persistence in eight study areas that became re-colonized by territorial wolves. The observed trends were generally consistent with the predictions of the mesopredator release hypothesis and supported the existence of top-down suppression by wolves on jackals. We observed inverse patterns of relative abundance and distribution for both canid species at various spatial scales. In most (seven out of eight) cases of wolf re-colonization of jackal territories, jackals disappeared or were displaced out or to the periphery of the newly established wolf home-ranges. We suggest that wolf extermination could be the key driver that enabled the expansion of jackals throughout Europe. Our results also indicate that top-down suppression may be weakened where wolves are intensively persecuted by humans or occur at reduced densities in human-dominated landscapes, which has important management implications and warrants further research. © 2017 Associazione Teriologica Italiana

Where to go next? Predicting habitat suitability of an expanding mesocarnivore: the golden jackal (Canis aureus) in Europe

The golden jackal’s Canis aureus range in Europe is expanding rapidly and populations are increasing. Historically restricted to the Mediterranean and Black sea coastal regions, jackals are now reproducing in most of Southeastern Europea and some Central European countries (1,2). In addition, dispersing animals have been detected further to the North and West (e.g. Belarus, Estonia, Finland, Germany, Switzerland). Two main causes have been suggested to explain this continental-scale range expansion: an improvement in human attitude and legal status, and a decrease and fragmentation of previously dense grey wolf Canis lupus populations (1,3,4). In particular, local evidence of golden jackals avoiding core areas occupied by wolves is accumulating in several countries e.g. Slovenia, Greece. From an applied perspective, the presence of this new carnivore could impact existing animal communities (5) and is already receiving high interest among wildlife managers. In this study, we used species distribution models to describe the golden jackal environmental niche and to identify areas of high habitat suitability, which are likely to be colonized in the future. Since jackals are highly mobile and opportunist animals, dispersers can temporarily occupy nearly all types of habitats. To prevent overestimation of the species’ environmental niche, we considered as presence only locations of established territorial jackal groups. These were contrasted with background points representing available environmental conditions. We controlled for sampling selection bias by manipulating presence weights and background spatial selection (6). We modeled the jackal environmental niche using annual duration of snow cover as well as ten land-cover variables. In addition, we included a grey wolf presence covariate derived from a categorical expert-based distribution map (7). All modeling was done at a 4km resolution, coherent with both jackal territory size and error associated with howling surveys (8). Within the core range of the species, we calibrated ten different model types and evaluated their performance considering both an internal evaluation (with a repeated split plot) and an external evaluation (with a geographically stratified cross-validation). Absence evaluation points were drawn from a combination of three data sources: hunting-statistics, expert-based distribution models and opportunistic jackal records. The final model was achieved through an ensemble model procedure and projected across the continent. Finally, we investigated the robustness of our predictions to extrapolation using a multivariate environmental surface analysis. We gathered a total of 1,517 recent locations of territorial jackal groups from 14 European countries (c. 80% from howling surveys and 20% from opportunistic records). Our model performed very well according to internal evaluation (AUC > 0.90 for GBM and MaxEnt). Snow cover duration and wolf presence were identified as the most important variables in explaining jackal distribution, followed by proportion of forest and agriculture, and distance from urban centers. Jackal relative probability of presence was highest in areas characterized with low snow cover duration and absence of permanent wolf populations. The presence of territorial jackal groups in areas of relatively long snow cover duration in Eastern Italy, where wolves are absent suggests that wolf presence is a relevant large-scale predictor of the jackal distribution. In addition, the low resolution of our wolf presence covariate certainly underestimates the importance of wolf presence in constraining jackal distribution. Four land cover covariates were also important predictors. Relative probability of presence was highest in areas of intermediary agriculture, medium-low forest, medium-low shrub and high water bodies prevalence. Hence, areas characterized by mosaic habitats seem to be most suitable, which confirms previous analyses of habitat selection at a finer scale (9). The ensemble model procedure reveals that large parts of Europe appear suitable for golden jackals (Figure 1.), so we can expect further expansion of this species in the future. These results provide managers with the opportunity to prepare for the jackal’s future colonization of areas where the expansion is most likely

Acoustic monitoring of golden jackals in Europe: setting the frame for future analyses

The golden jackal (Canis aureus) utters complex howls that can be used to monitor their population density and distribution in a specific area. However, little is known of the vocal behaviour of this species. In the present paper, we show the first results of the acoustic analysis that followed the acoustic monitoring of the golden jackal in Friuli\u2013Venezia Giulia during 2011\u20132013. We estimated the number of callers by screening the fundamental frequency of the emissions within a howl. We analysed 42 vocalizations given by a single jackal or multiple individuals. The howling duration significantly increased with the number of emitters, which ranged between one and three in our estimates. Twenty-nine howls were then submitted to a quantitative semi-automatic analysis procedure based on dynamic time warping. Based on the resulting dissimilarity indices, vocal emissions were clustered in six different acoustically uniform groups, which showed a potential for these procedures to be developed into future monitoring tools. The results suggest the need for integration between jackal howling, bioacoustics and camera trapping

Canid guild changes in Europe: evidence for a continental-scale mesopredator release of golden jackal (Canis aureus)

The golden jackal’s Canis aureus range in Europe is expanding rapidly and populations have increased significantly during the last decades. The presence of this new carnivore could impact existing animal communities and is already receiving high interest among wildlife managers. The decrease and fragmentation of previously dense grey wolf Canis lupus populations by humans have been suggested as potential trigger for such pattern. Historical trends in the populations of both canids and local evidence of golden jackal disappearance in areas recently recolonized by wolves tend to support this hypothesis. In this study, we developed species distribution models (SDMs) at a continental scale to investigate the golden jackal environmental niche and identify the potential influence of wolf presence on jackal habitat suitability. Since jackals are highly mobile and opportunistic animals, dispersers can temporarily move through nearly any habitat type. To prevent overestimation of the species’ environmental niche, we restricted our study to established territorial jackal groups sampled by means of acoustic stimulation. Nine di!erent SDM algorithms were calibrated and evaluated within the core distribution range of the species. We used environmental variables relevant to the species ecology: annual snow cover duration, land-cover and wolf presence; all uncorrelated and mapped at a 5 km resolution. Results/Conclusions We surveyed a total of 2,497 distinct locations across 11 European countries and detected 820 territorial jackal groups. GBM and Maxent algorithms performed best (average AUC = 0.91). Snow cover duration accounted for the highest variable contribution (37.2%), followed by wolf presence (20.8%). Forest and agricultural land prevalence, as well as distance from settlements and hydrological features were also selected in the best models. Jackal habitat suitability was highest in areas with short snow cover duration and heterogeneous land cover. Average jackal probability of presence ranged from 0.21 in areas of permanent wolf presence to 0.73 in areas of wolf absence. Although snow cover duration was the most influential variable to predict jackal distribution, the model predictive ability was significantly improved by including the wolf presence covariate; implying that grey wolf presence also significantly a!ects golden jackal habitat suitability. More generally, this analysis supports the hypothesis that jackal expansion in Europe was triggered by a large-scale mesopredator release following wolf persecution in 19th and 20th centur