Time distortion is an effect that makes the passage of time feel wildly altered and difficult to keep track of.    It can occur in form of four distinct subtypes: time dilation, time compression, time reversal, and atemporality. These four subtypes are described and documented below:
Time dilation is the feeling that time has slowed down.   This can create the perception that more time has passed than it actually has. For example, at the end of hallucinogenic experiences which typically last no longer than several hours, one may feel that they have subjectively undergone days, weeks, months, years, or even infinite periods of time.
Time dilation is often accompanied by other coinciding effects such as spirituality enhancement, novelty enhancement, thought loops, novelty enhancement, and internal hallucinations. This is seemingly because these particular effects can result in a person perceiving a disproportionately large number of novel events occurring within a much smaller frame of time than they usually would.
Time dilation is most commonly induced under the influence of strong dosages of hallucinogenic compounds, such as psychedelics  , dissociatives  , and cannabinoids  . However, it also commonly occurs during moments of extreme stress and fear. 
Time compression is the experience of time speeding up and passing much quicker than it usually would.    For example, during this state, a person may realize that an entire day or evening has passed them by in what feels like only a couple of hours.
This commonly occurs under the influence of stimulating compounds such as amphetamines and entactogens. With these particular substances, time compression seems to at least partially stem from the fact that during intense levels of stimulation and focus-enhancement, people typically become hyper-fixated on activities and tasks in a manner that causes them to both keep track of time less effectively and also become more likely to ignore any events which may be unfolding around them.
However, the same experience also commonly occurs in a different manner while under the influence of depressant compounds which induce amnesia, such as alcohol, GHB, and benzodiazepines. This is seemingly due to the way in which a person can forget events that occurred under the influence of the particular substance, thus giving the impression that they have suddenly jumped forward in time.
Time reversal is the experience of perceiving the events that occurred around oneself within the previous several minutes or several hours, spontaneously playing backwards in a manner similar to that of a rewinding VHS tape. During this reversal, the person's cognition and train of thought typically continues to play forward in a coherent and linear manner while they watch the external environment around them and their body's physical actions play in reverse. It is speculated that the experience of time reversal may potentially occur through a combination of visual hallucinations and errors in memory encoding.
Time reversal is often accompanied by other coinciding effects such as internal hallucinations, thought loops, and deja vu. It is most commonly induced under the influence of extremely heavy dosages of hallucinogenic compounds, such as psychedelics, dissociatives, and deliriants.
Atemporality is the experience of feeling as if one's conscious awareness is now outside of, disconnected from, and uninfluenced by the normal passage of linear time. During this state, there is often a sense that the flow of time has ceased to function and has also become inherently meaningless.
While experiencing atemporality, one’s ability to conceptualize ordinary time may be compromised in several ways. For example, the concept of ‘one hour’ may no longer make any sense. As a different example, the concepts of ‘one second’ and ‘one year’ may both seem like a single well-defined unit. The paradoxical sensation of ‘existing’ outside of time is also often connected to reports of being unable to adequately describe this effect using ordinary language.
Atemporality is often accompanied by other coinciding effects such as perception of eternalism and ego death. It is most commonly induced under the influence of heavy dosages of psychedelic compounds, such as LSD, DMT, psilocybin, and mescaline.
An experience of transcending time is also one among many criteria assessed by the MEQ-30, which is a standardized questionnaire used in clinical research observing how psychedelic-induced mystical experiences can occasion positive long-term changes in patients’ mental health. 
- VandenBos, G. R. (2013). APA dictionary of clinical psychology. American Psychological Association. | https://dictionary.apa.org/time-distortion
- VandenBos, G. R. (2013). APA dictionary of clinical psychology. American Psychological Association. | https://dictionary.apa.org/tachypsychia
- Meck, W. H. (1996). Neuropharmacology of timing and time perception. Cognitive brain research, 3(3-4), 227-242. | https://pubmed.ncbi.nlm.nih.gov/8806025/
- Phillips, I., Upadhyayula, A., & Flombaum, J. (2020). Tachypsychia—the subjective expansion of time—happens in immediate memory, not perceptual experience. Journal of Vision, 20(11), 1466-1466. | https://jov.arvojournals.org/article.aspx?articleid=2771214
- Colonnese, F. K. (2019). Revisionary temporal experiences: how a recognition of tachypsychia in verse alters interpretation (Doctoral dissertation, San Francisco State University). | http://sfsu-dspace.calstate.edu/handle/10211.3/213868
- Dawson, K. A. (2005). A psychedelic neurochemistry of time. | http://cogprints.org/4034/1/Psychedelic_Neurochemistry2.htm
- Coull, J. T., Morgan, H., Cambridge, V. C., Moore, J. W., Giorlando, F., Adapa, R., ... & Fletcher, P. C. (2011). Ketamine perturbs perception of the flow of time in healthy volunteers. Psychopharmacology, 218(3), 543-556. | https://link.springer.com/article/10.1007/s00213-011-2346-9
- Atakan, Z., Morrison, P., G Bossong, M., Martin-Santos, R., & A Crippa, J. (2012). The effect of cannabis on perception of time: a critical review. Current pharmaceutical design, 18(32), 4915-4922. | https://doi.org/10.2174/138161212802884852
- Vicario, C. M., & Felmingham, K. L. (2018). Slower time estimation in post-traumatic stress disorder. Scientific reports, 8(1), 1-8. | https://dx.doi.org/10.1038%2Fs41598-017-18907-5
- Friedman, W. J., & Janssen, S. M. (2010). Aging and the speed of time. Acta Psychologica, 134(2), 130-141. | https://doi.org/10.1016/j.actpsy.2010.01.004
- Barrett, F. S., Johnson, M. W., & Griffiths, R. R. (2015). Validation of the revised Mystical Experience Questionnaire in experimental sessions with psilocybin. Journal of Psychopharmacology, 29(11), 1182-1190. | https://dx.doi.org/10.1177%2F0269881115609019