Speed perception

Shinar D. and A. Ronen (2007). Validation of speed perception and production in STI-SIM single screen simulator. International Conference on Road Safety and Simulation, Rome, November. 

Distance and Speed Perception for Exterior Mirrors and Displays... 

The results for the CMS and the exterior mirror show that the distances of the last safe gap converge at speed level 50 km/h. It seems to be of great importance to explore the distance estimation for speeds higher than 50 km/h. The critical question is whether the tendency to underestimate the distance reverses at a certain (high) speed level and turns to an overestimation of the distance. This would have a negative impact on road safety, because vehicles would be perceived as more distant than they actually are. As the recommended speed on German motorways is 130 km/h, a distance and speed perception study according to the applied method is recommended up to this speed level. 

To conclude, this sampling of the literature of risk perception, the comments of Covello, 1981 may be summarized. Surveys have been of small specialized groups - generally not representative of the population as a whole. There has been little attempt to analyze the effects of ethnicity, religion, sex, region age, occupation and other variables that may affect risk perception. People respond to surveys with the first thing that comes to mind and tend to stick to this answer. They provide an answer to any question asked even when they have no opinion, do not understand the question or have inconsistent beliefs. Surveys are influenced by the order of questions, speed of response, whether a verbal or numerical respon.se is required and by how the answer is posed. Few Studies have examined the relationships between perceptions of technological hazards and behavior which seems to be influenced by several factors such as positive identification with a leader, efficacy of social and action, physical proximity to arenas of social conflict. 

Enantiomeric compounds differ from one another only in two aspects The chiroptical characteristics (optical rotation) and the speed of their reaction with chiral molecules. The human olfactory organ is also capable of distinguishing chiral molecules. The odor quality and potency of enantiomeric compounds may show considerable differences. Thus, distinct differentiation in odor perception could be observed in the pairs of enantiomeric oxygenated monoterpenoid odorants. " However, the... 

In Chapter 4 we discussed how Ayahuasca users often felt that they were freed from time. Past, present, and future lose their significance. In Chapter 2 we discussed how certain languages may shape or reflect different cultures notions of time. Your psychological perception of time is, of course, affected by such things as medications, time of day, your level of happiness, external stimuli, and even the temperature. Hypnosis can also cause time dilation, as can cannabis and LSD. Additionally, heat appears to speed up the activity of a chemical timepiece in the brain. For example, fever can severely speed your perception of time, perhaps partly because it speeds chemical processes. Opium is notorious for its effect on time perception. The English writer Thomas De Quincey reported... 

The term perception designates physiological and mental processes that serve to absorb and classify information from our internal and external environments. Speed, extent and quality of perception not only depend on the condition of the sensory organs but they are also a function of such factors as wakefulness, attentiveness or concentration, emotional and motivational state... 

Tachistoscopic trials serve to record speed and extent of perception. In the course of such experiments visual stimuli are shown for a very short time and the subject has to name the items presented as far as he has recognized them. Tests with simple configurations of stimuli (colors, single letters or objects) primarily record speed of perception, whereas experiments with more varied content also investigate elements of short-term memory. Tachistoscopic experiments are nowadays hardly used in pharmacopsychology, presumably because of their low sensitivity to the effects of substances. 

Because the literature on the effects of psychedelics frequently notes alterations in spatial perception, in size, and in the speed with which time passes, the conditions of no depth, expanded depth, blurred vision, clear and distinct vision, diminished size, enlarged size, fast time, slow time, and stopped time have been selected for inclusion here. Each of the time conditions involves an alteration of time by keying it to a metronome, as well as a verbal alteration of time. Interspersed through all the other conditions are control conditions, in which the subject is hypnotized, but no sugges-... 

Users often experience a mellow sense of wellbeing and relaxation that makes them feel expansive, creative, and more sensitive to all types of stimuli. Perception of time slows, and ability to gauge distance, depth, and speed accurately is distorted. Users can also spiral downward into anxiety, paranoia, panic attacks, and hallucinations. This effect is more pronounced when larger doses of THC are ingested, such as when hashish or other more concentrated forms of marijuana are used. Higher doses are also possible when marijuana is eaten rather than smoked this occurs when more of the drug is ingested before it can be metabolized. 

---