scholarly journals The Role of Attention in Motion Extrapolation: Are Moving Objects ‘Corrected’ or Flashed Objects Attentionally Delayed?

Perception ◽  
10.1068/p3066 ◽  
2000 ◽  
Vol 29 (6) ◽  
pp. 675-692 ◽  
Author(s):  
Beena Khurana ◽  
Katsumi Watanabe ◽  
Romi Nijhawan
Keyword(s):  
New York ◽  
Moving Objects ◽  
Reaction Times ◽  
Cost Benefit ◽  
Circular Path ◽  
Perceptual Awareness ◽  
Multiple Events ◽  
Attentional Deployment ◽  
Lag Effect ◽  
Elementary Psychology

Objects flashed in alignment with moving objects appear to lag behind [Nijhawan, 1994 Nature (London) 370 256–257], Could this ‘flash-lag’ effect be due to attentional delays in bringing flashed items to perceptual awareness [Titchener, 1908/1973 Lectures on the Elementary Psychology of Feeling and Attention first published 1908 (New York: Macmillan); reprinted 1973 (New York: Arno Press)]? We overtly manipulated attentional allocation in three experiments to address the following questions: Is the flash-lag effect affected when attention is (a) focused on a single event in the presence of multiple events, (b) distributed over multiple events, and (c) diverted from the flashed object? To address the first two questions, five rings, moving along a circular path, were presented while observers attentively tracked one or multiple rings under four conditions: the ring in which the disk was flashed was (i) known or (ii) unknown (randomly selected from the set of five); location of the flashed disk was (i) known or (ii) unknown (randomly selected from ten locations), The third question was investigated by using two moving objects in a cost – benefit cueing paradigm, An arrow cued, with 70% or 80% validity, the position of the flashed object, Observers performed two tasks: (a) reacted as quickly as possible to flash onset; (b) reported the flash-lag effect, We obtained a significant and unaltered flash-lag effect under all the attentional conditions we employed, Furthermore, though reaction times were significantly shorter for validly cued flashes, the flash-lag effect remained uninfluenced by cue validity, indicating that quicker responses to validly cued locations may be due to the shortening of post-perceptual delays in motor responses rather than the perceptual facilitation, We conclude that the computations that give rise to the flash-lag effect are independent of attentional deployment.

The Flash-Lag Effect during Illusory Chopstick Rotation

Perception ◽  
10.1068/p5653 ◽  
2007 ◽  
Vol 36 (7) ◽  
pp. 1043-1048 ◽  
Author(s):  
Stuart Anstis
Keyword(s):  
New York ◽  
Visual System ◽  
Moving Objects ◽  
Moving Object ◽  
Circular Path ◽  
Object A ◽  
Static Object ◽  
Lag Effect

In the ‘flash-lag’ effect, a static object that is briefly flashed next to a moving object appears to lag behind the moving object. A flash was put up next to an intersection that appeared to be moving clockwise along a circular path but was actually moving counterclockwise [the chopstick illusion; Anstis, 1990, in AI and the Eye Eds A Blake, T Troscianko (London: John Wiley) pp 105–117; 2003, in Levels of Perception Eds L Harris, M Jenkin (New York: Springer) pp 90–93]. As a result, the flash appeared displaced clockwise. This was appropriate to the physical, not the subjective, direction of rotation, and it suggests that the flash-lag illusion occurs early in the visual system, before motion signals are parsed into moving objects.

scholarly journals Eye-hand coordination during flexible manual interception of an abruptly appearing, moving target

2018 ◽  
Vol 119 (1) ◽  
pp. 221-234 ◽  
Author(s):  
Yuhui Li ◽  
Yong Wang ◽  
He Cui
Keyword(s):  
Eye Movements ◽  
Moving Objects ◽  
Reaction Times ◽  
Hand Movements ◽  
Moving Target ◽  
Target Displacement ◽  
Transmission Delays ◽  
Sensory Transmission ◽  
Hand Coordination ◽  
Different Levels

As a vital skill in an evolving world, interception of moving objects relies on accurate prediction of target motion. In natural circumstances, active gaze shifts often accompany hand movements when exploring targets of interest, but how eye and hand movements are coordinated during manual interception and their dependence on visual prediction remain unclear. Here, we trained gaze-unrestrained monkeys to manually intercept targets appearing at random locations and circularly moving with random speeds. We found that well-trained animals were able to intercept the targets with adequate compensation for both sensory transmission and motor delays. Before interception, the animals' gaze followed the targets with adequate compensation for the sensory delay, but not for extra target displacement during the eye movements. Both hand and eye movements were modulated by target kinematics, and their reaction times were correlated. Moreover, retinal errors and reaching errors were correlated across different stages of reach execution. Our results reveal eye-hand coordination during manual interception, yet the eye and hand movements may show different levels of prediction based on the task context. NEW & NOTEWORTHY Here we studied the eye-hand coordination of monkeys during flexible manual interception of a moving target. Eye movements were untrained and not explicitly associated with reward. We found that the initial saccades toward the moving target adequately compensated for sensory transmission delays, but not for extra target displacement, whereas the reaching arm movements fully compensated for sensorimotor delays, suggesting that the mode of eye-hand coordination strongly depends on behavioral context.

Noisy Motorcycles and Barriers and Quieter Pavements for Traffic Noise Abatement: Summaries of Two TQA Workshops

2021 ◽  
Vol 263 (2) ◽  
pp. 4144-4153
Author(s):  
Paul Donavan
Keyword(s):  
New York ◽  
Cost Benefit Analysis ◽  
Traffic Noise ◽  
Cost Benefit ◽  
Round Table ◽  
Test Methods ◽  
Standard Test ◽  
Noise Mitigation ◽  
Community Noise ◽  
National Cooperative

In the Technology for a Quieter America report, motorcycles were mentioned three times, once in terms of standard test methods and twice in relation to community noise. In New York City, motorcycles placed in the top 10 bothersome noise sources identified by residents. Although there are regulated levels that manufacturers must meet, complaints about in-service motorcycle noise persist. To address this issue, a round table meeting was held in August 2012 with a broad spectrum of participants representing manufacturers, regulators, and other interested, knowledgeable engineers. In preparation of the TQA report, a workshop entitled Cost-Benefit Analysis (CBA) for Noise Control found that CBA was being applied in the area of traffic noise mitigation in regard to the use of barriers and/or quieter pavement. To address the particular CBA issues for this topic, a workshop was held in January 2014 with state and federal transportation officials and the research team responsible for the National Cooperative Highway Research Program NCHRP Report 738, Evaluating Pavement Strategies and Barriers for Noise Mitigation. The findings of these two meetings are summarized in this paper.

43 COSTS RELATED TO ESTRUS SYNCHRONIZATION AND AI PROTOCOLS IN CROSSBRED HOLSTEIN-ZEBU DAIRY COWS

2010 ◽  
Vol 22 (1) ◽  
pp. 179
Author(s):  
L. D. P. Sinedino ◽  
B. T. Gerhardt ◽  
A. P. Dourado ◽  
L. A. G. Nogueira
Keyword(s):  
New York ◽  
Dairy Cows ◽  
Pregnancy Rate ◽  
Animal Health ◽  
Cost Benefit ◽  
Estradiol Benzoate ◽  
Estrus Synchronization ◽  
Labor Costs ◽  
Estrus Detection ◽  
The Cost

The objective of this paper was to compare 3 bovine AI protocols, evaluating the cost of each treatment and the pregnancy rates obtained, to demonstrate the importance of routine utilization of estrus synchronization techniques. The experiment was conducted in the Farm School of Cachoeiras de Macacu of the Federal Fluminense University, in the state of Rio de Janeiro, during the period from 2006 to 2007 (August to June). One hundred sixteen crossbred female Holstein-Zebu dairy cows in cycle, with body condition between 2.5 to 4 (on a scale from 1 to 5), were selected and divided randomly in 3 groups (G). Animals in G1 [n = 60; 21 heifers (H), 13 primiparous (P), and 26 multiparous (M)], with palpable corpus luteum, received 25 mg of prostaglandin F2 intravulvar, and AI was done 12 h after estrus detection. For animals in G2 (n = 30; 11 H, 6 P, and 13 M) an intravaginal progesterone device (CIDR®, Pfizer Animal Health, New York, NY, USA) was inserted and 2 mg of estradiol benzoate (EB) was administered i.m. on Day 0. On Day 8 the device was removed and 25 mg of prostaglandin was administered i.m. on Day 9, 2 mg of EB was administered, and 30 h later, timed AI of all animals was performed. For G3 (n = 26; 9 H, 5 P, and 12 M), the protocol used was similar to that for G2, except that on Day 8 400 IU of eCG was administered (in addition to the removal of the device) and on Day 9 the dose of EB was reduced to 1 mg and timed AI was done 27 h later. AI was done with semen from 2 sires with proven fertility, by the same technician. The pregnancy diagnoses were done on Day 45 by palpation per rectum and transrectal ultrasonography. The cost-benefit relation was calculated according to the cost of pharmaceuticals multiplied by the number of animals in each experimental group divided by the number of pregnancies obtained in each one, without considering the manual labor costs in all the groups and considering 3 uses of the CIDR. The statistical analyses were done using chi-square test. The pregnancy rate obtained in G2 (60%, 18/30) was superior to that in G1 (30%, 18/60) (P < 0.05), demonstrating the efficiency of the treatment that utilized progesterone. G3 (53.85%, 14/26) was similar (P > 0.05) to G2, despite the fact that the eCG was added in this group. In reference to cost-benefit, considering only the pharmaceuticals costs and the value for pregnancy obtained in each group, the costs found, respectively, were G1 U$7.02 and U$23.66; G2 U$28.57 and U$47.59; and G3 U$47.96 and U$89.05. The lowest cost in the estrus synchronization was based on the use of prostaglandins alone; the use of progesterone increased the synchronization cost, but also increased the pregnancy rate and eliminated the need for estrus observation. The addition of eCG in cows that are cycling does not necessarily demand a increase in pregnancy rate. Failure in estrus detection, using prostaglandin alone, increased the interval from calving, causing a daily loss in milk production, which justified the investment in protocols of estrus and ovulation synchronization, contributing to increase the reproductive efficiency of a dairy cow herd.

scholarly journals Racial Inequities in the Federal Buyout of Flood-Prone Homes: A Nationwide Assessment of Environmental Adaptation

2020 ◽  
Vol 6 ◽  
pp. 237802312090543 ◽  
Author(s):  
James R. Elliott ◽  
Phylicia Lee Brown ◽  
Kevin Loughran
Keyword(s):  
New York ◽  
Cost Benefit ◽  
Flood Damage ◽  
Hurricane Sandy ◽  
Environmental Adaptation ◽  
County Level ◽  
Government Programs ◽  
Local Implementation ◽  
Racial Privilege ◽  
Neighborhood Level

One way the U.S. government is responding to the challenges of climate change is by funding the purchase of tens of thousands of flood-prone homes in more than 500 cities and towns across the country. This study provides a nationwide analysis of that program, extending beyond cost-benefit calculations to investigate racial inequities at different scales of local implementation, from county-level adoption, through neighborhood-level participation, to homeowner approval. Statistical analyses indicate that net of local flood damage, population, and incomes, the program disproportionately targets whiter counties and neighborhoods, especially in more urbanized areas where the program now concentrates. Yet it is neighborhoods of color in these areas that have been historically more likely to accept buyouts in greater numbers. The exception is the New York and New Jersey area after Hurricane Sandy. Implications for understanding how racial privilege works through government programs aimed at encouraging environmental adaptation are discussed.

scholarly journals Optimal Smoothing in Visual Motion Perception

2001 ◽  
Vol 13 (6) ◽  
pp. 1243-1253 ◽  
Author(s):  
Rajesh P. N. Rao ◽  
David M. Eagleman ◽  
Terrence J. Sejnowski
Keyword(s):  
Visual System ◽  
Moving Objects ◽  
Visual Motion ◽  
Moving Object ◽  
Motion Direction ◽  
Visual Motion Perception ◽  
Statistical Framework ◽  
Lag Effect ◽  
Propagation Delays ◽  
Optimal Smoothing

When a flash is aligned with a moving object, subjects perceive the flash to lag behind the moving object. Two different models have been proposed to explain this “flash-lag” effect. In the motion extrapolation model, the visual system extrapolates the location of the moving object to counteract neural propagation delays, whereas in the latency difference model, it is hypothesized that moving objects are processed and perceived more quickly than flashed objects. However, recent psychophysical experiments suggest that neither of these interpretations is feasible (Eagleman & Sejnowski, 2000a, 2000b, 2000c), hypothesizing instead that the visual system uses data from the future of an event before committing to an interpretation. We formalize this idea in terms of the statistical framework of optimal smoothing and show that a model based on smoothing accounts for the shape of psychometric curves from a flash-lag experiment involving random reversals of motion direction. The smoothing model demonstrates how the visual system may enhance perceptual accuracy by relying not only on data from the past but also on data collected from the immediate future of an event.

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