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Visual trails: do the doors of perception open periodically?

Dubois J, Vanrullen R - PLoS Biol. (2011)

View Article: PubMed Central - PubMed

Affiliation: Université de Toulouse, Centre de Recherche Cerveau et Cognition, Université Paul Sabatier, Toulouse, France. jcrdubois@gmail.com

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“Visual trailing” is a transient but dramatic disturbance of visual motion perception of unknown origin: the subject perceives a series of discrete stationary images trailing in the wake of otherwise normally moving objects... Although this phenomenon is most frequently encountered after ingestion of prescription and/or illicit drugs (most commonly with lysergic acid diethylamid, or LSD), it has also occasionally been reported following brain damage or neurological disorders... LSD users perceive a series of discrete positive afterimages in the wake of moving objects, a percept that has been likened to a multiple-exposure stroboscopic photograph, somewhat akin to Etienne-Jules Marey's chronophotographs from 1880, or to more recent digital art produced in a few clicks (Figure 1)... Nefazodone, for instance, is a recent antidepressant drug with multiple reports of episodes of visual trails as a side effect –,... A closely related antidepressant drug, trazodone, can induce similar side effects ; so can mirtazapine, and, possibly, risperidone (the study is inconclusive due to the concurrent administration of trazodone )... The symptoms are referred to as akinetopsia/polyopia by the authors, but their description corresponds to a direction-specific version of trailing (visual trails are perceived when objects move from right to left, but not when they move from left to right)... Direction-specificity restricts the mechanistic models that can be put forward to explain visual trails; however, the etiology is very different from previously discussed cases, and in the absence of other reports of directional trailing, it is premature to draw conclusions from this report... M. permanently lost motion perception (except for slowly moving objects )... For example, motion streak suppression is an inhibitory mechanism allowing the brain to regulate the smear that a moving object leaves in its wake, owing to visible persistence (an image normally takes about 100 ms to fade from perception, long enough to blur the trajectory of a moving object as in a long-exposure photograph)... Under the effects of LSD or related drugs, the streak suppression process might fall out of its normal operating range, resulting in stronger than normal local inhibition followed by excitatory rebound... In fact, some of the most experienced users indicated that trailing is dose dependent... For all these reasons, one must be cautious in interpreting these initial results... Collecting further quantitative data with individuals who experience visual trailing will be necessary to tease apart the alternative accounts—possibly in combination with computational modeling... Solving the mystery of the origins of the trailing effect might reveal something deep about the mechanisms underlying perception, challenging the way we think we perceive the world.

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Multiple-exposure stroboscopic photograph.This illustrates (inasmuch as possible with a static image) the perception                        experienced during trailing.
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pbio-1001056-g001: Multiple-exposure stroboscopic photograph.This illustrates (inasmuch as possible with a static image) the perception experienced during trailing.

Mentions: Ask any LSD user: they know the drug is taking effect when the “good trails” kick in. Trailing is a visual perceptual effect commonly experienced during LSD consumption and as a long-lasting side effect of the drug (hallucinogen persisting perception disorder) [1]–[4]. LSD users perceive a series of discrete positive afterimages in the wake of moving objects, a percept that has been likened to a multiple-exposure stroboscopic photograph, somewhat akin to Etienne-Jules Marey's chronophotographs [5] from 1880, or to more recent digital art produced in a few clicks (Figure 1).


Visual trails: do the doors of perception open periodically?

Dubois J, Vanrullen R - PLoS Biol. (2011)

Multiple-exposure stroboscopic photograph.This illustrates (inasmuch as possible with a static image) the perception                        experienced during trailing.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3091843&req=5

pbio-1001056-g001: Multiple-exposure stroboscopic photograph.This illustrates (inasmuch as possible with a static image) the perception experienced during trailing.
Mentions: Ask any LSD user: they know the drug is taking effect when the “good trails” kick in. Trailing is a visual perceptual effect commonly experienced during LSD consumption and as a long-lasting side effect of the drug (hallucinogen persisting perception disorder) [1]–[4]. LSD users perceive a series of discrete positive afterimages in the wake of moving objects, a percept that has been likened to a multiple-exposure stroboscopic photograph, somewhat akin to Etienne-Jules Marey's chronophotographs [5] from 1880, or to more recent digital art produced in a few clicks (Figure 1).

View Article: PubMed Central - PubMed

Affiliation: Université de Toulouse, Centre de Recherche Cerveau et Cognition, Université Paul Sabatier, Toulouse, France. jcrdubois@gmail.com

AUTOMATICALLY GENERATED EXCERPT
Please rate it.

“Visual trailing” is a transient but dramatic disturbance of visual motion perception of unknown origin: the subject perceives a series of discrete stationary images trailing in the wake of otherwise normally moving objects... Although this phenomenon is most frequently encountered after ingestion of prescription and/or illicit drugs (most commonly with lysergic acid diethylamid, or LSD), it has also occasionally been reported following brain damage or neurological disorders... LSD users perceive a series of discrete positive afterimages in the wake of moving objects, a percept that has been likened to a multiple-exposure stroboscopic photograph, somewhat akin to Etienne-Jules Marey's chronophotographs from 1880, or to more recent digital art produced in a few clicks (Figure 1)... Nefazodone, for instance, is a recent antidepressant drug with multiple reports of episodes of visual trails as a side effect –,... A closely related antidepressant drug, trazodone, can induce similar side effects ; so can mirtazapine, and, possibly, risperidone (the study is inconclusive due to the concurrent administration of trazodone )... The symptoms are referred to as akinetopsia/polyopia by the authors, but their description corresponds to a direction-specific version of trailing (visual trails are perceived when objects move from right to left, but not when they move from left to right)... Direction-specificity restricts the mechanistic models that can be put forward to explain visual trails; however, the etiology is very different from previously discussed cases, and in the absence of other reports of directional trailing, it is premature to draw conclusions from this report... M. permanently lost motion perception (except for slowly moving objects )... For example, motion streak suppression is an inhibitory mechanism allowing the brain to regulate the smear that a moving object leaves in its wake, owing to visible persistence (an image normally takes about 100 ms to fade from perception, long enough to blur the trajectory of a moving object as in a long-exposure photograph)... Under the effects of LSD or related drugs, the streak suppression process might fall out of its normal operating range, resulting in stronger than normal local inhibition followed by excitatory rebound... In fact, some of the most experienced users indicated that trailing is dose dependent... For all these reasons, one must be cautious in interpreting these initial results... Collecting further quantitative data with individuals who experience visual trailing will be necessary to tease apart the alternative accounts—possibly in combination with computational modeling... Solving the mystery of the origins of the trailing effect might reveal something deep about the mechanisms underlying perception, challenging the way we think we perceive the world.

Show MeSH