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11.
Antje Nuthmann 《Visual cognition》2013,21(7):803-837
The current study investigated from how large a region around their current point of gaze viewers can take in information when searching for objects in real-world scenes. Visual span size was estimated using the gaze-contingent moving window paradigm. Experiment 1 featured window radii measuring 1, 3, 4, 4.7, 5.4, and 6.1°. Experiment 2 featured six window radii measuring between 5 and 10°. Each scene occupied a 24.8 × 18.6° field of view. Inside the moving window, the scene was presented in high resolution. Outside the window, the scene image was low-pass filtered to impede the parsing of the scene into constituent objects. Visual span was defined as the window size at which object search times became indistinguishable from search times in the no-window control condition; this occurred with windows measuring 8° and larger. Notably, as long as central vision was fully available (window radii ≥ 5°), the distance traversed by the eyes through the scene to the search target was comparable to baseline performance. However, to move their eyes to the target, viewers made shorter saccades, requiring more fixations to cover the same image space, and thus more time. Moreover, a gaze-data based decomposition of search time revealed disruptions in specific subprocesses of search. In addition, nonlinear mixed models analyses demonstrated reliable individual differences in visual span size and parameters of the search time function. 相似文献
12.
By means of the moving window paradigm, we examined how many letters can be identified during a single eye fixation and whether this letter identity span changes as a function of reading skill. The results revealed that 8-year-old Finnish readers identify approximately 5 characters, 10-year-old readers identify approximately 7 characters, and 12-year-old and adult readers identify approximately 9 characters to the right of fixation. Comparison with earlier studies revealed that the letter identity span is smaller than the span for identifying letter features and that it is as wide in Finnish as in English. Furthermore, the letter identity span of faster readers of each age group was larger than that of slower readers, indicating that slower readers, unlike faster readers, allocate most of their processing resources to foveally fixated words. Finally, slower second graders were largely not disrupted by smaller windows, suggesting that their word decoding skill is not yet fully automatized. 相似文献
13.
If and Then: A Critique of Speculative NanoEthics 总被引:7,自引:4,他引:3
Alfred Nordmann 《Nanoethics》2007,1(1):31-46
Most known technology serves to ingeniously adapt the world to the physical and mental limitations of human beings. Humankind
has acquired awesome power with its rather limited means. Nanotechnological capabilities further this power. On some accounts,
however, nanotechnological research will contribute to a rather different kind of technological development, namely one that
changes human beings so as to remove or reduce their physical and mental limitations. The prospect of this technological development
has inspired a fair amount of ethical debate. Here, proponents and opponents of such visions of human enhancement are criticized
alike for engaging in speculative ethics. This critique exposes a general pattern that extends to other nano-, bio-, or neuroethical
debates. While it does not apply to all discussions of “enhancement technologies” it does apply to all ethical discourse that
constructs and validates an incredible future which it only then proceeds to endorse or critique. This discourse violates
conditions of intelligibility, squanders the scarce and valuable resource of ethical concern, and misleads by casting remote
possibilities or philosophical thought-experiments as foresight about likely technical developments. In effect, it deflects
consideration from the transformative technologies of the present.
相似文献
Alfred NordmannEmail: |
14.
While background subtraction techniques have been widely applied to detect moving objects in a video stream captured by a static camera, detecting moving objects using a moving camera still represents a challenging task. In this context, pedestrian detection using a camera placed on the top of a vehicle’s windshield has been rarely investigated. This is mainly due to the background ego-motion. Since the scene captured by the camera seems in motion, it is very difficult to distinguish the moving pedestrians from the others that belong to the static part of the scene. For this reason, a compensation step is needed to suppress the ego-motion. This paper presents a study on the main challenges facing pedestrian detection systems as well as methods proposed to handle these challenges. A novel trajectory classification framework for detecting pedestrians even in challenging real-world environments is proposed. The proposed method models the background motion between two consecutive frames in order to compensate the camera motion. Then, it defines a classification process that differentiates between the background and the foreground in the frame. Using the defined foreground, we consequently identify the presence of pedestrians in the scene. The proposed method was validated on a public benchmark dataset: CVC-14 containing both visible and far infrared video sequences in day and night times. Experimental results confirm the effectiveness of the proposed approach in capturing the dynamic aspect between frames and therefore detecting the presence of pedestrians in the scene. 相似文献
15.
Stefania Balzarotti Federica Cavaletti Adriano D'Aloia Barbara Colombo Elisa Cardani Maria Rita Ciceri Alessandro Antonietti Ruggero Eugeni 《Cognitive Science》2021,45(4):e12969
The present study examined whether cinematographic editing density affects viewers’ perception of time. As a second aim, based on embodied models that conceive time perception as strictly connected to the movement, we tested the hypothesis that the editing density of moving images also affects viewers’ eye movements and that these later mediate the effect of editing density on viewers’ temporal judgments. Seventy participants watched nine video clips edited by manipulating the number of cuts (slow- and fast-paced editing against a master shot, unedited condition). For each editing density, multiple video clips were created, representing three different kinds of routine actions. The participants’ eye movements were recorded while watching the video, and the participants were asked to report duration judgments and subjective passage of time judgments after watching each clip. The results showed that participants subjectively perceived that time flew more while watching fast-paced edited videos than slow-paced or unedited videos; by contrast, concerning duration judgments, participants overestimated the duration of fast-paced videos compared to the master-shot videos. Both the slow- and the fast-paced editing generated shorter fixations than the master shot, and the fast-paced editing led to shorter fixations than the slow-paced editing. Finally, compared to the unedited condition, editing led to an overestimation of durations through increased eye mobility. These findings suggest that the editing density of moving images by increasing the number of cuts effectively altered viewers’ experience of time and add further evidence to prior research showing that performed eye movement is associated with temporal judgments. 相似文献
16.
《Quarterly journal of experimental psychology (2006)》2013,66(3):483-499
The objectives of the current study were: (a) to determine whether perception–action coupling controlled behaviours when walking through moving doors and (b) to determine how vision contributed to this behaviour. Participants (N = 6) walked along a 7-m path toward two motor-driven doors, which moved at rates ranging between 20 and 40 cm/s. Each door was independently driven such that both moved at the same velocity (symmetrical) or at different velocities (asymmetrical). The results showed that in both door movement conditions the participants controlled their approach velocity by slowing down prior to crossing the doors. The decrease in walking velocity produced greater velocity variability in the final stages prior to crossing the doors and high success rates. The results from the gaze behaviours showed that fixation durations were significantly longer when the doors moved asymmetrically, suggesting that the visual information from this unpredictable environment took longer to process. However, the fixation patterns were similar between the two door movement conditions. Regardless of the door movement condition, the participants spent about 60% of each trial fixating environmental objects (i.e., left door, right door, or aperture). The majority of fixations were directed towards one of the doors at the beginning of the trial and then shifted towards the aperture in the final phase. The participants were using perception–action coupling to control their behaviours in the final phase in order to steer locomotion through the aperture. 相似文献
17.
Sigmund Valaker Eric Arne Lofquist Yantsislav Yanakiev Dominique Kost 《Military psychology》2013,25(6):390-405
Coordination is critical to the success of multinational military operations and may be fostered by predeployment training. We argue that whether such training is related to a high degree of perceived coordination at the individual level is likely to depend on whether individuals experience a low degree of organizational obstacles to information sharing. We examined this using data from the North Atlantic Treaty Organization (NATO) Kosovo Force headquarters (survey: n = 131). We controlled for whether it was the participants’ first deployment, the participants’ background (military or civilian), the amount of time spent in the headquarters by participants, whether differences pertaining to culture and opinions were valued by the organization, the quality of supervisor/subordinate relationships, and the degree of national cultural obstacles to information sharing. The results showed no significant direct effects on coordination from 3 different training configurations: national training, multinational training, and a combination of national and multinational training. However, we found a negative direct effect from organizational obstacles to information sharing on coordination, and support for organizational obstacles to information sharing as negatively moderating the multinational predeployment training and coordination relationship. Qualitative interviews (n = 14) indicated that informal information sharing, and the problems exchanging information from tactical to operational levels could hinder coordination. Interventions to foster coordination could benefit from a focus on multinational training and lowering organizational obstacles to information sharing. Our findings contribute to more precisely pinpointing the types of training that are useful in multinational operations, as well as the factors upon which training transfer is contingent. 相似文献
18.
The objectives of this study were: (a) to determine if the control mechanism for interacting with a dynamic real environment is the same as in the virtual reality (VR) studies, and (b) to identify the action control parameters that are modulated to successfully pass through oscillating doors. The participants walked along a 14-m path towards oscillating doors (rate of change in aperture size = 44 cm/s and maximum aperture varied 70, 80, or 100 cm). The participants had to use vision to extrapolate what the aperture of the doors would be at the time of crossing and determine if a change in action parameters was necessary. If their current state did not match the required state then the participants made modifications to their actions. The results showed that individuals in a real environment used similar action modifications (i.e., velocity adjustments) as those seen in VR studies to increase success. Aside from the gradual velocity adjustments observed, there was an immergence of a different locomotor action parameter on some trials that was not seen in VR studies (i.e., shoulder rotations). These shoulder rotations occurred when the participants perceived that a velocity adjustment alone would not lead to a successful trial. These results show that participants use perception to control movement in a feedback rather than feedforward manner. 相似文献
19.
Antje Nuthmann Madeleine E. L. Beveridge Richard C. Shillcock 《Visual cognition》2014,22(3-4):259-282
Readers utilize parafoveal information about upcoming words and read less well when this information is denied. McConkie and Rayner (1975) enabled this issue to be explored by developing the moving window paradigm in which the experimenter varies the amount or the quality of the parafoveal information available around the current fixation point. We present a novel binocular version of the moving window technique to study the roles of the two eyes in reading, and we describe a basic experiment allowed by this technique. In the binocular moving window paradigm, each eye contributes its own window to a composite binocular window onto the text. We studied the reading of single lines of text in three conditions: no windows, a symmetrical 8-letters-left and 8-letters-right window for each eye, and a leftward-skewed 14-letters-left and 2-letters-right window for each eye. Note that both eyes saw the composite window onto the text. We tested the hypothesis that readers could be encouraged to generate a greater binocular disparity to augment their window onto the text and to provide a greater preview for one eye. The data offered limited support for this prediction. We observed considerable individual differences in both baseline fixation disparity and in readers' response to the critical asymmetric [14,2] window. 相似文献
20.
When individuals strive towards personal goals, they may encounter obstacles that could compromise their goal progress and pose a challenge to self-regulation. Coping with obstacles first requires those obstacles to be identified. The purpose of the present studies was to apply an inter-individual approach to this important, but insufficiently studied self-regulatory aspect of goal striving. We therefore examined the role of self-awareness, that is, paying attention to one's own feelings, thoughts, and behaviours, for the identification of goal-related obstacles. We measured and manipulated self-awareness in two correlational and two experimental studies (one of them preregistered) and asked participants to identify obstacles to their goals. All studies confirmed the hypothesis that individuals with higher levels of dispositional and situational self-awareness identify more obstacles, both with regard to their idiosyncratic personal goals (Studies 1 and 2) and with regard to a goal in an assigned task during an experiment (Studies 3 and 4). The results indicate that self-awareness plays a crucial role for identifying obstacles. We discuss the implications of our findings for personality and self-regulation research. 相似文献