Tracers by Chelsea Morgan - This replication serves as an accurate representation of distinct tracers seen behind the path of a moving hand.
Tracers are the experience of trails of varying lengths and opacity being left behind moving objects in a manner that is similar to those found in long exposure photography. [1] These can manifest as exactly the same colour of the moving object which is producing it or can sometimes be a randomly selected colour of their own. A relatively consistent way to reproduce this visual effect is to simply move one's hand in front of their face or throw an object under the influence of a moderate dose of psychedelics. This effect is capable of manifesting itself across the 4 different levels of intensity described below:
  1. Subtle - At the lowest level, tracers can be described as an almost completely transparent after image which disappears quickly and drags closely behind moving objects.
  2. Distinct - At this level, tracers increase in length to become roughly half as long as the distance across the visual field which the object it is following has travelled. The clarity of these tracers shifts from barely visible to distinct and partially transparent in colour.
  3. Intense - At this level, tracers become mostly solid in appearance and almost completely opaque with increasingly distinct and sharp edges. This creates a clear contrast between the tracer itself and the background behind it. The tracers become slower to fade from a person’s vision and can remain in the air for up to several seconds. This results in longer trails covering the entire distance across the visual field which the object creating it has moved.
  4. All-encompassing - At the highest level, a person’s visual field has become so sensitive to the creation of tracers that it entirely smudges and blurs into an all-encompassing tracer at the slightest movement of an object or the eye. This can make it extremely difficult to see unless one’s eyes are kept still in a motionless environment as tracers linger almost indefinitely or until one looks elsewhere within their visual field.
Tracers are often accompanied by other coinciding effects such as drifting and after images. They are most commonly induced under the influence of mild dosages of psychedelic [2] [3] compounds, such as LSD [4] [5] [6] [7] , psilocybin, and mescaline. However, they can also occur less commonly under the influence of certain stimulants and dissociatives such as MDMA or 3-MeO-PCP.


  1. Dubois, J., & VanRullen, R. (2011). Visual trails: do the doors of perception open periodically?. PLoS biology, 9(5), e1001056. |
  2. Abraham, H. D., Mccann, U. D., & Ricaurte, G. A. (2002). Psychedelic drugs. |
  3. Anderson, W. H., & O'Malley, J. E. (1972). Trifluoperazine for the trailing phenomenon. JAMA, 220(9), 1244-1245. |
  4. Asher, H. (1971). Trailing” phenomenon–a long-lasting LSD side effect. Am J Psychiatry, 127(9), 1233-4. |
  5. Schwartz, K. (1997). Nefazodone and visual side effects. The American journal of psychiatry, 154(7), 1038. |
  6. Abraham, H. D. (1983). Visual phenomenology of the LSD flashback. Arch Gen Psychiatry, 40(8), 886-887. |
  7. Abraham, H. D., & Wolf, E. (1988). Visual function in past users of LSD: Psychophysical findings. Journal of Abnormal Psychology, 97(4), 443. |




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