scholarly journals Spatiotemporal Characteristics of 360-Degree Basic Attention

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Yuki Harada ◽  
Junji Ohyama

Abstract The spatiotemporal characteristics of basic attention are important for understanding attending behaviours in real-life situations, and they are useful for evaluating the accessibility of visual information. However, although people are encircled by their 360-degree surroundings in real life, no study has addressed the general characteristics of attention to 360-degree surroundings. Here, we conducted an experiment using virtual reality technology to examine the spatiotemporal characteristics of attention in a highly controlled basic visual context consisting of a 360-degree surrounding. We measured response times and gaze patterns during the 360-degree search task and examined the spatial distribution of attention and its temporal variations in a 360-degree environment based on the participants’ physical position. Data were collected from both younger adults and older adults to consider age-related differences. The results showed the fundamental spatiotemporal characteristics of 360-degree attention, which can be used as basic criteria to analyse the structure of exogenous effects on attention in complex 360-degree surroundings in real-life situations. For practical purposes, we created spherical criteria maps of 360-degree attention, which are useful for estimating attending behaviours to 360-degree environmental information or for evaluating visual information design in living environments, workspaces, or other real-life contexts.


Author(s):  
Toby J. Lloyd-Jones ◽  
Juergen Gehrke ◽  
Jason Lauder

We assessed the importance of outline contour and individual features in mediating the recognition of animals by examining response times and eye movements in an animal-object decision task (i.e., deciding whether or not an object was an animal that may be encountered in real life). There were shorter latencies for animals as compared with nonanimals and performance was similar for shaded line drawings and silhouettes, suggesting that important information for recognition lies in the outline contour. The most salient information in the outline contour was around the head, followed by the lower torso and leg regions. We also observed effects of object orientation and argue that the usefulness of the head and lower torso/leg regions is consistent with a role for the object axis in recognition.



2021 ◽  
pp. 112067212110057
Author(s):  
Pierre Gascon ◽  
Prithvi Ramtohul ◽  
Charles Delaporte ◽  
Sébastien Kerever ◽  
Danièle Denis ◽  
...  

Purpose: To report the visual and anatomic outcomes in treatment-naïve neovascular age-related macular degeneration (nAMD) patients treated with aflibercept under a standardized Treat and Extend (T&E) protocol for up to 3 years of follow-up in “real-life” practice. Methods: This retrospective, observational, multicenter study included patients with treatment-naïve nAMD and at least 12 months of follow-up. T&E regimen adjustment was initiated after loading phase. At each visit best-corrected visual acuity (BCVA) and optical coherence tomography parameters were performed. Results: One hundred and thirty-six eyes of 115patients had at least 1 year of follow-up with 114 and 82 eyes completing at least 2 and 3 years of follow-up, respectively (mean follow-up duration: 2.7 ± 1.3 years). Mean age was 78.6 ± 8.6 years old and 52% were women. Mean BCVA increased from 60.6 ± 18.7 letters at diagnosis to 66.9 ± 16.2 letters at 1 year (+6.3 letters, p = 0.003) and remained stable throughout the follow-up period (63.1 ± 20.3 letters (+2.5, p = 0.1) and 64.0 ± 20.1 letters (+3.4, p = 0.27) at 2 and 3 years, respectively). The mean central retinal thickness decreased significantly from 358.2 ± 87.9 µm at baseline to 302 ± 71.7 µm at 12 months and maintained stable after 36 months of follow-up (297.1 ± 76 µm, p < 0.0001). Mean number of injections was 6.6 ± 2.2, 4.8 ± 1.9, and 5.6 ± 1.7 at 1, 2, and 3 years, respectively. Mean cumulative number of 16.4 ± 5.6 injections after 3 years. Mean treatment interval was 6.8 ± 2.5 weeks at 1 year. Eight-week and 12-week treatment interval were achieved in 59.5% and 19.1%, 65.8%, and 36.8% and 69.5% and 41.5% at 1, 2, and 3 years, respectively. Conclusions: Our study demonstrated that intravitreal injections of aflibercept initiated under a standardized T&E for patients with treatment-naïve nAMD allow for significant visual improvement at 12 months, which was maintained over a 3-year follow-up period.



2021 ◽  
Vol 25 ◽  
pp. 233121652110144
Author(s):  
Ilja Reinten ◽  
Inge De Ronde-Brons ◽  
Rolph Houben ◽  
Wouter Dreschler

Single microphone noise reduction (NR) in hearing aids can provide a subjective benefit even when there is no objective improvement in speech intelligibility. A possible explanation lies in a reduction of listening effort. Previously, we showed that response times (a proxy for listening effort) to an auditory-only dual-task were reduced by NR in normal-hearing (NH) listeners. In this study, we investigate if the results from NH listeners extend to the hearing-impaired (HI), the target group for hearing aids. In addition, we assess the relevance of the outcome measure for studying and understanding listening effort. Twelve HI subjects were asked to sum two digits of a digit triplet in noise. We measured response times to this task, as well as subjective listening effort and speech intelligibility. Stimuli were presented at three signal-to-noise ratios (SNR; –5, 0, +5 dB) and in quiet. Stimuli were processed with ideal or nonideal NR, or unprocessed. The effect of NR on response times in HI listeners was significant only in conditions where speech intelligibility was also affected (–5 dB SNR). This is in contrast to the previous results with NH listeners. There was a significant effect of SNR on response times for HI listeners. The response time measure was reasonably correlated ( R142 = 0.54) to subjective listening effort and showed a sufficient test–retest reliability. This study thus presents an objective, valid, and reliable measure for evaluating an aspect of listening effort of HI listeners.



Author(s):  
José Manuel Rodríguez-Ferrer

We have studied the effects of normal aging on visual attention. Have participated a group of 38 healthy elderly people with an average age of 67.8 years and a group of 39 healthy young people with average age of 19.2 years. In a first experiment of visual detection, response times were recorded, with and without covert attention, to the presentation of stimuli (0.5º in diameter grey circles) appearing in three eccentricities (2.15, 3.83 and 5.53° of visual field) and with three levels of contrast (6, 16 and 78%). In a second experiment of visual form discrimination circles and squares with the same features as in the previous experiment were presented, but in this case subjects only should respond to the emergence of the circles. In both age groups, the covert attention reduced response times. Compared to young people, the older group achieved better results in some aspects of attention tests and response times were reduced more in the stimuli of greater eccentricity. The data suggest that there is a mechanism of adaptation in aging, in which visual attention especially favors the perception of those stimuli more difficult to detec



1983 ◽  
Vol 27 (5) ◽  
pp. 354-354
Author(s):  
Bruce W. Hamill ◽  
Robert A. Virzi

This investigation addresses the problem of attention in the processing of symbolic information from visual displays. Its scope includes the nature of attentive processes, the structural properties of stimuli that influence visual information processing mechanisms, and the manner in which these factors interact in perception. Our purpose is to determine the effects of configural feature structure on visual information processing. It is known that for stimuli comprising separable features, one can distinguish between conditions in which only one relevant feature differs among stimuli in the array being searched and conditions in which conjunctions of two (or more) features differ: Since the visual process of conjoining separable features is additive, this fact is reflected in search time as a function of array size, with feature conditions yielding flat curves associated with parallel search (no increase in search time across array sizes) and conjunction conditions yielding linearly increasing curves associated with serial search. We studied configural-feature stimuli within this framework to determine the nature of visual processing for such stimuli as a function of their feature structure. Response times of subjects searching for particular targets among structured arrays of distractors were measured in a speeded visual search task. Two different sets of stimulus materials were studied in array sizes of up to 32 stimuli, using both tachistoscope and microcomputer-based CRT presentation for each. Our results with configural stimuli indicate serial search in all of the conditions, with the slope of the response-time-by-array-size function being steeper for conjunction conditions than for feature conditions. However, for each of the two sets of stimuli we studied, there was one configuration that stood apart from the others in its set in that it yielded significantly faster response times, and in that conjunction conditions involving these particular stimuli tended to cluster with the feature conditions rather than with the other conjunction conditions. In addition to these major effects of particular targets, context effects also appeared in our results as effects of the various distractor sets used; certain of these context effects appear to be reversible. The effects of distractor sets on target search were studied in considerable detail. We have found interesting differences in visual processing between stimuli comprising separable features and those comprising configural features. We have also been able to characterize the effects we have found with configural-feature stimuli as being related to the specific feature structure of the target stimulus in the context of the specific feature structure of distractor stimuli. These findings have strong implications for the design of symbology that can enhance visual performance in the use of automated displays.





2021 ◽  
pp. 112067212110378
Author(s):  
Francesco Ciucci ◽  
Giuseppina Ioele ◽  
Antonio Bardocci ◽  
Giorgio Lofoco ◽  
Barbara Antonelli ◽  
...  

Purpose: This is a retrospective, single-center, non randomized interventional real life study, investigating the correlation between variability of central retinal thickness (CRT) and functional outcomes during 2 years of anti-VEGF therapy in patients treated for neovascular age related macular degeneration (nAMD). Background: CRT fluctuations can depend on various factors such as the correct timing of injections, the therapeutic algorithm, and the number of injections (NI) performed; it is important to understand if CRT fluctuations are responsible for worse visual outcomes and consequently to identify the correct ways to avoid or reduce them. Methods: Forty-one patients were treated for nAMD with aflibercept: 0.5 mg intravitreal aflibercept was administered every 4 weeks during the first 3 months, then bimonthly over the first year, and after the first year adopting a PRN regimen. Standard deviation of CRT (CRT/SD), BCVA, and NI were recorded. Correlation studies were performed by Pearson’s test, Ancova, and Principal Component Analysis. Results: A negative correlation was found between CRT/SD and final BCVA. In patients who lost more than 15 letters, CRT/SD mean was significantly higher in comparison with patients who lost less than 15 letters. Patients with final BCVA >65 letters showed lower CRT/SD values compared to patients with final BCVA ⩽65 letters. Multivariate analysis confirmed that in patients with higher baseline BCVA, improvement of BCVA was correlated to NI, and lower values of CRT fluctuations were observed. Conclusions: CRT fluctuations, even after an appropriate NI given per year, significantly influence BCVA; a proactive treatment algorithm appears crucial when treating patients with nAMD.



1989 ◽  
Vol 17 (5) ◽  
pp. 48-54 ◽  
Author(s):  
J. M. Smith ◽  
G. Q. Maguire


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