The hyperpersonal model of computer-mediated communication (CMC) posits that users exploit the technological aspects of CMC in order to enhance the messages they construct to manage impressions and ...facilitate desired relationships. This research examined how CMC users managed message composing time, editing behaviors, personal language, sentence complexity, and relational tone in their initial messages to different presumed targets, and the cognitive awareness related to these processes. Effects on several of these processes and outcomes were obtained in response to different targets, partially supporting the hyperpersonal perspective of CMC, with unanticipated gender and status interaction effects suggesting behavioral compensation through CMC, or overcompensation when addressing presumably undesirable partners.
Chemical constituents in otoliths have become a valuable tool for fish ecologists seeking to reconstruct migratory patterns and life‐history diversity in a wide range of species worldwide. This ...approach has proved particularly effective with fishes that move across substantial salinity gradients over the course of their life, including many diadromous species. Freshwater endmembers of several elemental and isotope ratios (e.g. Sr:Ca, Ba:Ca and 87Sr:86Sr) are typically identifiably distinct from marine values, and often differ among freshwater tributaries at fine spatial scales. Because these chemical tags are generally incorporated in proportion to their ambient dissolved concentrations, they can be effective proxies for quantifying the presence, duration and frequency of movements between freshwater and marine habitats. The development of high precision probe‐based analytical techniques, such as laser ablation inductively coupled plasma mass spectrometry (ICP‐MS) and microbeam methods, has allowed researchers to glean increasingly detailed life‐history profiles of these proxies across otoliths. Researchers are also combining multiple chemical proxies in an attempt to refine interpretations of habitat residence patterns. A thorough understanding of the spatial and temporal variation in water chemistry as well as environmental and physiological controls on incorporation of specific elements into otoliths is required for confident estimation of lifetime salinity experience. First some assumptions, methodological considerations and data processing options that are particularly relevant to diadromous otolith chemistry studies are discussed. Insights into diadromous migrations obtained from decades of otolith chemistry research, highlighting the increasingly recognized importance of contingent behaviour and partial migration are then discussed. Finally, areas for future research and the need to integrate otolith chemistry studies into comprehensive assessments of the effects of global environmental change are identified.
This book explores the social forces among and between online aggressors that affect the expression and perpetration of online hate. Its chapters illustrate how patterns of interactive social ...behavior reinforce, magnify, or modify this expression. It also considers the characteristics of social media that facilitate social interactions that promote hate and facilitate relationships among haters. Bringing together a range of international experts and covering an array of themes, including woman abuse, antisemitism, pornography, radicalization, and extreme political youth movements, this book examines the specific social factors and processes that facilitate these forms of hate and proposes new approaches for explaining them. Cutting-edge, interdisciplinary, and authoritative, this book will be of interest to sociologists, criminologists, and scholars of media, communication, and computational social science alike, as well as those engaged with hate crime, hate speech, social media, and online social networks.
We quantified the relative contributions of water and food to strontium (Sr) and barium (Ba) deposited in otoliths of juvenile mummichogsFundulus heteroclitus. Fish were reared in seawater spiked ...with86Sr and137Ba significantly beyond natural values to obtain distinct isotopic signatures for water and food. Element abundances (Sr:Ca and Ba:Ca) and isotope ratios (88Sr:86Sr and138Ba:137Ba) were quantified in water samples using solution-based inductively coupled plasma-mass spectrometry (ICP-MS), and88Sr:86Sr and138Ba:137Ba ratios in otoliths were quantified using laser ablation ICP-MS. The relative contributions of water and food sources to otolith aragonite were assessed using a simple linear isotope mixing model. Water sources contributed 83% of Sr and 98% of Ba in otoliths formed in spiked seawater. Our results indicate that water chemistry is the dominant factor controlling the uptake of Sr and Ba in the otoliths of marine fishes. Thus, chemical signatures recorded in the otoliths of marine fishes should reflect the ambient water composition of these elements at the time of deposition.
Human subjects are extremely efficient at categorizing natural scenes, despite the fact that different classes of natural scenes often share similar image statistics. Thus far, however, it is unknown ...where and how complex natural scene categories are encoded and discriminated in the brain. We used functional magnetic resonance imaging (fMRI) and distributed pattern analysis to ask what regions of the brain can differentiate natural scene categories (such as forests vs mountains vs beaches). Using completely different exemplars of six natural scene categories for training and testing ensured that the classification algorithm was learning patterns associated with the category in general and not specific exemplars. We found that area V1, the parahippocampal place area (PPA), retrosplenial cortex (RSC), and lateral occipital complex (LOC) all contain information that distinguishes among natural scene categories. More importantly, correlations with human behavioral experiments suggest that the information present in the PPA, RSC, and LOC is likely to contribute to natural scene categorization by humans. Specifically, error patterns of predictions based on fMRI signals in these areas were significantly correlated with the behavioral errors of the subjects. Furthermore, both behavioral categorization performance and predictions from PPA exhibited a significant decrease in accuracy when scenes were presented up-down inverted. Together these results suggest that a network of regions, including the PPA, RSC, and LOC, contribute to the human ability to categorize natural scenes.
Where to draw the line? Sheng, Heping; Wilder, John; Walther, Dirk B
PloS one,
11/2021, Volume:
16, Issue:
11
Journal Article
Peer reviewed
Open access
We often take people's ability to understand and produce line drawings for granted. But where should we draw lines, and why? We address psychological principles that underlie efficient ...representations of complex information in line drawings. First, 58 participants with varying degree of artistic experience produced multiple drawings of a small set of scenes by tracing contours on a digital tablet. Second, 37 independent observers ranked the drawings by how representative they are of the original photograph. Matching contours between drawings of the same scene revealed that the most consistently drawn contours tend to be drawn earlier. We generated half-images with the most- versus least-consistently drawn contours and asked 25 observers categorize the quickly presented scenes. Observers performed significantly better for the most compared to the least consistent half-images. The most consistently drawn contours were more likely to depict occlusion boundaries, whereas the least consistently drawn contours frequently depicted surface normals.
In complex real-world scenes, image content is conveyed by a large collection of intertwined visual features. The visual system disentangles these features in order to extract information about image ...content. Here, we investigate the role of one integral component: the content of spatial frequencies in an image. Specifically, we measure the amount of image content carried by low versus high spatial frequencies for the representation of real-world scenes in scene-selective regions of human visual cortex. To this end, we attempted to decode scene categories from the brain activity patterns of participants viewing scene images that contained the full spatial frequency spectrum, only low spatial frequencies, or only high spatial frequencies, all carefully controlled for contrast and luminance. Contrary to the findings from numerous behavioral studies and computational models that have highlighted how low spatial frequencies preferentially encode image content, decoding of scene categories from the scene-selective brain regions, including the parahippocampal place area (PPA), was significantly more accurate for high than low spatial frequency images. In fact, decoding accuracy was just as high for high spatial frequency images as for images containing the full spatial frequency spectrum in scene-selective areas PPA, RSC, OPA and object selective area LOC. We also found an interesting dissociation between the posterior and anterior subdivisions of PPA: categories were decodable from both high and low spatial frequency scenes in posterior PPA but only from high spatial frequency scenes in anterior PPA; and spatial frequency was explicitly decodable from posterior but not anterior PPA. Our results are consistent with recent findings that line drawings, which consist almost entirely of high spatial frequencies, elicit a neural representation of scene categories that is equivalent to that of full-spectrum color photographs. Collectively, these findings demonstrate the importance of high spatial frequencies for conveying the content of complex real-world scenes.
Reconstructing fish movements is critical to understand the diversity of habitats required to sustain mobile species. Chemical constituents in otoliths have been invaluable for the field of fish ...migration ecology to track natal origins and reconstruct lifetime movement patterns. However, alternative non-lethal structures, such as scales, are preferred for imperiled species to avoid mortality. We analyzed 29 individual scales from highly migratory and vulnerable Atlantic tarpon Megalops atlanticus (hereafter referred to as tarpon) in the Gulf of Mexico to identify migrations across salinity gradients and associated trophic shifts using paired measurements of elemental (Sr/Ca) and isotopic (δ13C and δ15N) proxies. Although tarpon can inhabit freshwater, the specific patterns of facultative oligohaline habitat use are unknown. Individual scale-based salinity and diet histories were highly variable, with 4 contingents identified depending on the presence and sequence of movements. Scale salinity proxies (Sr/Ca and δ13C) indicated that tarpon spent on average 42 ± 34% of their scale-based life histories within oligohaline habitats. Transhaline movements were accompanied by shifts in δ15N that indicated putative trophic shifts between marine or estuarine and oligohaline food webs. Oligohaline habitat use is common yet individually facultative for tarpon. This information is critical to devise sustainable fisheries management plans that account for the full range of diverse habitats used by this species throughout its life. Chemical analyses of scales have the potential to be broadly informative about migrations and trophic interactions in species where lethal methods must be avoided.
Despite over two decades of research on the neural mechanisms underlying human visual scene, or place, processing, it remains unknown what exactly a “scene” is. Intuitively, we are always inside a ...scene, while interacting with the outside of objects. Hence, we hypothesize that one diagnostic feature of a scene may be concavity, portraying “inside”, and predict that if concavity is a scene-diagnostic feature, then: 1) images that depict concavity, even non-scene images (e.g., the “inside” of an object – or concave object), will be behaviorally categorized as scenes more often than those that depict convexity, and 2) the cortical scene-processing system will respond more to concave images than to convex images. As predicted, participants categorized concave objects as scenes more often than convex objects, and, using functional magnetic resonance imaging (fMRI), two scene-selective cortical regions (the parahippocampal place area, PPA, and the occipital place area, OPA) responded significantly more to concave than convex objects. Surprisingly, we found no behavioral or neural differences between images of concave versus convex buildings. However, in a follow-up experiment, using tightly-controlled images, we unmasked a selective sensitivity to concavity over convexity of scene boundaries (i.e., walls) in PPA and OPA. Furthermore, we found that even highly impoverished line drawings of concave shapes are behaviorally categorized as scenes more often than convex shapes. Together, these results provide converging behavioral and neural evidence that concavity is a diagnostic feature of visual scenes.
Humans are remarkably efficient at categorizing natural scenes. In fact, scene categories can be decoded from functional MRI (fMRI) data throughout the ventral visual cortex, including the primary ...visual cortex, the parahippocampal place area (PPA), and the retrosplenial cortex (RSC). Here we ask whether, and where, we can still decode scene category if we reduce the scenes to mere lines. We collected fMRI data while participants viewed photographs and line drawings of beaches, city streets, forests, highways, mountains, and offices. Despite the marked difference in scene statistics, we were able to decode scene category from fMRI data for line drawings just as well as from activity for color photographs, in primary visual cortex through PPA and RSC. Even more remarkably, in PPA and RSC, error patterns for decoding from line drawings were very similar to those from color photographs. These data suggest that, in these regions, the information used to distinguish scene category is similar for line drawings and photographs. To determine the relative contributions of local and global structure to the human ability to categorize scenes, we selectively removed long or short contours from the line drawings. In a category-matching task, participants performed significantly worse when long contours were removed than when short contours were removed. We conclude that global scene structure, which is preserved in line drawings, plays an integral part in representing scene categories.
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