The Beep-Speed Illusion: Non-Spatial Tones Increase Perceived Speed of Visual Objects in a Forced-Choice Paradigm

We introduce a new audio-visual illusion revealing the interplay between audio-visual integration and selective visual attention. This illusion involves two simultaneously moving objects that change their motion trajectory occasionally, but only the direction changes of one object are accompanied by spatially uninformative tones. We observed a selective increase in perceived object speed of the audio-visually synchronized object by measuring the point of subjective equality in a forced-choice paradigm. The illusory increase in perceived speed of the audio-visually synchronized object persisted when preventing eye movements. Using temporally matched color changes of the synchronized object also increased the perceived speed. Yet, using color changes of a surrounding frame instead of tones had no effect on perceived speed ruling out simple alertness explanations. Thus, in contrast to coinciding tones, visual coincidences only elicit illusory increases in perceived speed when the coincidence provided spatial information. Taken together, our pattern of results suggests that audio-visual synchrony attracts visual attention towards the coinciding visual object, leading to an increase in speed-perception and thus shedding new light on the interplay between attention and multisensory feature integration. We discuss potential limitations such as the choice of paradigm and outline prospective research question to further investigate the effect of audio-visual integration on perceived object speed.

The effect of blue light filtering lenses on speed perception

Blue-light filtering lenses (BFLs) are marketed to protect the eyes from blue light that may be hazardous to the visual system. Because BFLs attenuate light, they reduce object contrast, which may impact visual behaviours such as the perception of object speed which reduces with contrast. In the present study, we investigated whether speed perception is affected by BFLs. Using a two-interval forced-choice procedure in conjunction with Method of Constant Stimuli, participants (n = 20) judged whether the perceived speed of a moving test stimulus (1.5–4.5°/s) viewed through a BFL was faster than a reference stimulus (2.75°/s) viewed through a clear lens. This procedure was repeated for 3 different BFL brands and chromatic and achromatic stimuli. Psychometric function fits provided an estimate of the speed at which both test and reference stimuli were matched. We find that the perceived speed of both chromatic and achromatic test stimuli was reduced by 6 to 20% when viewed through BFLs, and lenses that attenuated the most blue-light produced the largest reductions in perceived speed. Our findings indicate that BFLs whilst may reduce exposure to hazardous blue light, have unintended consequences to important visual behaviours such as motion perception.

Romanian Medical Students’ Attitude towards and Perceived Knowledge on COVID-19 Vaccination

In Romania, the first phase of the COVID-19 vaccination campaign prioritized medical personnel, which included healthcare students. This study aimed to assess their knowledge, attitudes towards, and perception of COVID-19 vaccination. An anonymous, single-answer, 42-item online survey was conducted from 12 January until 3 March 2021, in the country’s largest University of Medicine and Pharmacy. Among the 1581 respondents (14.9% response rate), 88.5% were pro-vaccination, 7.8% were undecided, and 3.7% were vaccine resistant. The main reason for vaccine rejection was the perceived speed of vaccine development (strong agreement among the vaccine resistant, moderate agreement among the undecided, p < 0.001). Concern over long-term adverse reaction was present in only 11.5% of the respondents, significantly more frequent in the undecided and vaccine resistant. Perceived knowledge on the vaccines’ safety, efficacy, and technology correlated with a pro-vaccine attitude (p < 0.001). Most respondents had a positive stance towards vaccination in general, influencing their behaviour as future parents (99.3% of the pro-vaccination, 95.1% of the undecided, and 89.1% of the vaccine resistant will vaccinate their children, p < 0.001) and as medical professionals (99.7% of the pro-vaccination, 93.5% of those undecided, and 89.8% of the vaccine resistant would advise parents to vaccinate their children, p < 0.001). Healthcare students can thus serve as important vectors for scientifically sound information, influencing vaccine uptake in the community.

Motion extrapolation in the flash-lag effect depends on perceived, rather than physical speed

In the flash-lag effect (FLE), a flash in spatiotemporal alignment with a moving object is often misperceived as lagging behind the moving object. One proposed explanation for the illusion is based on predictive motion extrapolation of trajectories. In this interpretation, observers require an estimate of the object′s velocity to anticipate future positions, implying that the FLE is dependent on a neural representation of perceived velocity. By contrast, alternative models of the FLE based on differential latencies or temporal averaging should not rely on such a representation of velocity. Here, we test the extrapolation account by investigating whether the FLE is sensitive to illusory changes in perceived speed when physical speed is actually constant. This was tested using rotational wedge stimuli with variable noise texture (Experiment 1) and luminance contrast (Experiment 2). We show for both manipulations, differences in perceived speed corresponded to differences in the FLE: dynamic versus static noise, and low versus high contrast stimuli led to increases in perceived speed and FLE magnitudes. These effects were consistent across different textures and were not due to low-level factors. Our results support the idea that the FLE depends on a neural representation of velocity, which is consistent with mechanisms of motion extrapolation. Hence, the faster the perceived speed, the larger the extrapolation, the stronger the flash-lag.

PENGARUH PERSEPSI KENYAMANAN DALAM PENGGUNAAN DIGITAL PAYMENT TERHADAP PERILAKU KONSUMTIF MASYARAKAT DI ERA INDUSTRI 4.0 DENGAN PERSEPSI KECEPATAN SEBAGAI VARIABEL MODERATING

This study aims to examine the effect of perceived convenience in the use of digital payment on consumptive behavior in the industrial era 4.0 with perceived speed as a moderating variable. The sample used in this study is the digital payment user community in the Province of Yogyakarta Special Region. The sample study used convenience sampling method and obtained 91 respondents. This research uses SmartPLS 3.3.3 software. The results show that the perceived convenience of using digital payments has no effect on people's consumptive behavior in the industrial era 4.0 and the perception of speed cannot strengthen the influence of perceived convenience in using digital payments on people's consumptive behavior in the industrial era 4.0.

Having Children Speeds up the Subjective Passage of Lifetime in Parents

A widely reproduced finding across numerous studies of different cultures is that adults perceive the most recent 10 years of their lives to have passed particularly fast, and that this perceived speed increases as they grow older. Potential explanatory factors for this effect are believed to be more routines in life as we age as well as an increase in time pressure during middle adult age, both factors that would lead to a reduced autobiographical memory load. Fewer contextual changes in life are known to cause the passage of time to be perceived as faster. Taking advantage of the database created for the study that first captured this age effect on subjective time (Wittmann & Lehnhoff, 2005), we investigated the role that having children plays in the subjective speeding of time. Adults aged between 20 and 59 who had children reported that time over the last 10 years passed subjectively more quickly than adults of the same age group without children. Factors such as education or gender did not influence subjective time. A small correlation effect could be seen in the fact that parents with more children reported that time passed more quickly. Experienced time pressure was not a differentiating factor between the two groups, as time pressure was associated with a faster passage of time in all adults. Future systematic studies will have to reveal what factors on autobiographical memory and time might be accountable for this clear effect that raising children has on perceived time.

A review of the footsteps illusion

Studies on the footsteps illusion proposed by Anstis (2001) and its variants are reviewed in this article. The footsteps illusion has been explained as a difference in perceived speed depending on edge contrast (Thompson, 1982). In addition to this explanation, it is suggested that the footsteps illusion and its variants can also be attributed to the geometrical illusion presented by Gregory and Heard (1983), to the extinction effect similar to hidden images by Wade (1990), and to subsequent position or motion captures. Related illusions, for example, the kickback illusion (Howe, Thompson, Anstis, Sagreiya, & Livingstone, 2006), the kick-forward illusion, the driving-on-a-bumpy-road illusion, or the footsteps illusion based upon reverse phi motion, are discussed in this article.