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Time perception is a field of study within psychology and neuroscience. It refers to the sense of time, which differs from other senses since time cannot be directly perceived but must be reconstructed by the brain. Humans can perceive relatively short periods of time, in the order of milliseconds, and also durations that are a significant fraction of a lifetime. Human perception of duration is subjective and variable. Some researchers attempt to categorize people by how they differ in their perception of time (see "Personality characteristics" below).
Pioneering work, emphasizing species-specific differences, was done by Karl Ernst von Baer. Experimental work began under the influence of the psycho-physical notions of Gustav Theodor Fechner with studies of the relationship between perceived and measured time.
- The strength model of time memory. This posits a memory trace that persists over time, by which one might judge the age of a memory (and therefore how long ago the event remembered occurred) from the strength of the trace. This conflicts with the fact that memories of recent events may fade more quickly than more distant memories.
- The inference model suggests the time of an event is inferred from information about relations between the event in question and other events whose date or time is known.
Although the sense of time is not associated with a specific sensory system, the work of psychologists and neuroscientists indicates that human brains do have a system governing the perception of time composed of a highly distributed system involving the cerebral cortex, cerebellum and basal ganglia. One particular component, the suprachiasmatic nucleus, is responsible for the circadian (or daily) rhythm, while other cell clusters appear to be capable of shorter-range (ultradian) timekeeping.
Experiments have shown that rats can successfully estimate intervals of time around 40 seconds despite having their cortex entirely removed, which suggests it is a low level (subcortical) process.
Specious present 
The specious present is the time duration wherein a state of consciousness is experienced as being in the present. The term was first introduced by the philosopher E. R. Clay. and further developed by William James. James defined the specious present to be "the prototype of all conceived times... the short duration of which we are immediately and incessantly sensible". C. D. Broad in "Scientific Thought" (1930) further elaborated on the concept of the specious present, and considered that the Specious Present may be considered as the temporal equivalent of a sensory datum.. A version of the concept was used by Edmund Husserl in his works and discussed further by Francisco Varela based on the writings of Husserl, Heidegger, and Merleau-Ponty.
Psychologists assert that time seems to go faster with age, but the literature on this age-related perception of time remains controversial. One day to an eleven-year-old would be approximately 1/4,000 of their life, while one day to a 55-year-old would be approximately 1/20,000 of their life. This is perhaps why a day would appear much longer to a young child than to an adult. In an experiment comparing a group of subjects aged between 19 and 24 and a group between 60 and 80 asked to estimate when they thought 3 minutes had passed, it was found that the younger group's estimate was on average 3 minutes and 3 seconds, while the older group averaged 3 minutes and 40 seconds, indicating a change in the perception of time with age. People tend to recall recent events as occurring further back in time (backward telescoping) and distant events occurring more recently (forward telescoping).
It has also been proposed that the subjective experience of time changes with age due to changes in the individual's biological makeup.
Illusions of time 
A temporal illusion is a distortion in sensory perception caused when the time between the occurrence of two or more events is very short (typically less than a second). In such cases a person may misperceive the temporal order of the events. The kappa effect is a form of temporal illusion verifiable by experiment whereby time intervals between visual events are perceived as relatively longer or shorter depending on the relative spatial positions of the events. In other words, the perception of temporal intervals appears to be directly affected, in these cases, by the perception of spatial intervals. The Kappa effect can be displayed when considering a journey made in two parts that take an equal amount of time. Between these two parts, the journey that covers more distance will appear to take longer than the journey covering less distance, even though they take an equal amount of time.
The stopped clock illusion, where the seconds hand of a clock appears to freeze in place when initially looked at, is another illusion of time perception. Later it was found that saccadic eye movements could cause compression of time as well as space. Terao, Watanabe, Yagi, & Nishida (2005) were able to show that reducing the visibility of a flash by means of dimming was sufficient in reducing time interval estimation. Taken together these findings suggest that when vision is tainted in some way, as in the case of a saccade when vision is blurred or in the case of a dimmed flash when the flash is harder to identify, that time perception is also affected.
Psychoactive substances 
Psychoactive drugs can alter the judgement of time. Some – such as entheogens – may also dramatically alter a person's temporal judgement. Substances such as LSD, psilocybin, and mescaline may affect our time perception. At higher doses time may appear to slow down, stop, speed up, go backwards or even seem out of sequence. In a 2007 study by Marc Wittman et al., psilocybin was found to significantly impair one's ability to reproduce interval durations longer than 2.5 seconds, significantly impair synchronizing motor actions (taps on a computer keyboard) to regularly occurring tones, and impair one's ability to keep tempo when asked to tap on a key at a self paced but consistent interval. In 1955, British MP Christopher Mayhew took mescaline hydrochloride in an experiment under the guidance of his friend, Dr Humphry Osmond. On the BBC documentary The Beyond Within, he described that half a dozen times during the experiment, he had "a period of time that didn't end for me".
Stimulants can lead both humans and rats to overestimate time intervals, while depressants can have the opposite effect. The level of activity in the brain of neurotransmitters such as dopamine and norepinephrine may be the reason for this.
Altered states 
Hypnosis and emotional state can affect the perception of time. Researchers from the University of Texas Health Science Center at Houston and Baylor College of Medicine found that although retrospective time estimations after a bungee jump were slower than the actual duration, there was no evidence for a slowing of time perception during the event. However, this experiment has been extensively critiqued.[unreliable source?]
Clinical disorders 
Parkinson's disease, schizophrenia, and attention deficit hyperactivity disorder (ADHD) have been linked to abnormalities in dopamine levels in the brain as well as to noticeable impairments in time perception. Neuropharmacological research indicates that the internal clock, used to time durations in the seconds-to-minutes range, is linked to dopamine function in the basal ganglia.
In his book "Awakenings", Oliver Sacks discusses how patients with Parkinson's disease experience deficits in their awareness of time and tempo. For example, Mr. E, when asked to clap his hands steadily and regularly did so for the first few claps before clapping faster and irregularly; culminating in an apparent freezing of motion. When he finished, Mr. E asked if his observers were glad he did it correctly to which they replied "no". Mr. E was offended by this because to him, his claps were regular and steady. When given L-DOPA, these deficits are lessened or subside entirely depending on the dose. This case not only shows that Parkinson's disease is related to time perception deficits but it also demonstrates how dopamine is involved.
Dopamine is also theorized to play a role in the attention deficits present with attention deficit hyperactivity disorder. Specifically, dopaminergic systems are involved in working memory and inhibitory processes, both of which are believed central to ADHD pathology. Children with ADHD have also been found to be significantly impaired on time discrimination tasks (telling the difference between two stimuli of different temporal lengths) and respond earlier on time reproduction tasks (duplicating the duration of a presented stimulus) than normal controls.
Along with other perceptual abnormalities, it has been noted by psychologists that schizophrenia patients have an altered sense of time. This was first described in psychology by Minkowski in 1927. Many schizophrenic patients stop perceiving time as a flow of causally linked events. It has been suggested that there is a delay in time perception in schizophrenic patients compared to normal subjects.
These defects in time perception may play a part in the hallucinations and delusions experienced by schizophrenic patients according to some studies. Some researchers suggest that "abnormal timing judgment leads to a deficit in action attribution and action perception."
Personality characteristics 
Some researchers aim to explain the differences between people in the way they relate to the time they have to perform different tasks. They claim that time perception is influenced by both internal-personal characteristics and by external-environmental factors. Some theorists suggest that time perception is categorized by two axes: "time perspective" and "time urgency" and these ideas have been used in occupational psychology settings. These axes create four personality types that differ in their personal characteristics and the way they deal with tasks.
See also 
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- SW Brown, DA Stubbs (1992). "Attention and interference in prospective and retrospective timing". Perception 21 (4): 545–57. doi:10.1068/p210545. PMID 1437469.
- "The Experience and Perception of Time". Retrieved 2009-10-22.
- "Brain Areas Critical To Human Time Sense Identified". UniSci – Daily University Science News. 2001-02-27.
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- James, W. (1893). The principles of psychology. New York: H. Holt and Company. Page 609.
- Anonymous (E. Robert Kelly), The Alternative: A Study in Psychology. London: Macmillan and Co., 1882.
- Andersen, Holly; Rick Grush (pending). A brief history of time-consciousness: historical precursors to James and Husserl (PDF). Journal of the History of Philosophy. Retrieved 2008-02-02.
- "The Specious Present: A Neurophenomenology of Time Consciousness." In Petitot, Varela, Pacoud & Roy (eds.), Naturalizing Phenomenology. Stanford University Press.
- Gruber, Ronald P.; Wagner, Lawrence F.; Block, Richard A. (2000). "Subjective Time Versus Proper (Clock) Time". In Buccheri, R.; Di Gesù, V.; Saniga, Metod. Studies on the structure of time: from physics to psycho(patho)logy. Springer. p. 54. ISBN 0-306-46439-X., Extract of page 54
- Robert, Adler. "Look how time flies . . .". Retrieved 2009-10-22.
- New Scientist magazine: Why time flies in old age
- It Seems Like Only Yesterday: The Nature and Consequences of Telescoping Errors in Marketing Research. Journal of Consumer Psychology.
- Svetlana V. Ukraintseva (2001). "Aging and the subjective sense of time". Current Concepts in Experimental Gerontology.
- Wada Y, Masuda T, Noguchi K, 2005, "Temporal illusion called 'kappa effect' in event perception" Perception 34 ECVP Abstract Supplement
- Yarrow K, Haggard P, Heal R, Brown P, Rothwell JC (2001). "Illusory perceptions of space and time preserve cross-saccadic perceptual continuity". Nature 414 (1): 302–305.
- Morrone MC, Ross J, Burr D (2005). "Saccadic eye movements cause compression of time as well as space". Nature Neuroscience 8 (1): 950–954.
- Terao M, Watanabe J, Yagi A, Nishida S (2008). "Reduction of stimulus visibility compresses apparent time intervals". Nature Neuroscience 11 (1): 541–542.
- Wittmann M, Carter O, Hasler F, Cahn BR, Grimberg U, Spring P, Hell D, Flohr H, Vollenweider FX (2007). "Effects of psilocybin on time perception and temporal control of behavior in humans". Journal of Psychopharmachology 21 (1): 50–64.
- Wittmann, M.; Leland DS, Churan J, Paulus MP. (8 October 2007). "Impaired time perception and motor timing in stimulant-dependent subjects". Drug Alcohol Depend. 90 (2–3): 183–92. doi:10.1016/j.drugalcdep.2007.03.005. PMC 1997301. PMID 17434690.
- Cheng, Ruey-Kuang; Macdonald, Christopher J.; Meck, Warren H. (2006). "Differential effects of cocaine and ketamine on time estimation : Implications for neurobiological models of interval timing". Pharmacology, biochemistry and behavior 85 (1): 114–122. doi:10.1016/j.pbb.2006.07.019. PMID 16920182.
- Tinklenberg, Jared R.; Walton T. Roth1; Bert S. Kopell (January 1976). "Marijuana and ethanol: Differential effects on time perception, heart rate, and subjective response". Psychopharmacology 49 (3): 275–279. doi:10.1007/BF00426830. PMID 826945.
- Arzy, Shahar; Istvan Molnar-Szakacs; Olaf Blanke (2008-06-18). "Self in Time: Imagined Self-Location Influences Neural Activity Related to Mental Time Travel". The Journal of Neuroscience 28 (25): 6502–6507. doi:10.1523/JNEUROSCI.5712-07.2008. PMID 18562621. Retrieved 2008-08-25.
- Bowers, Kenneth; Brenneman, HA (January 1979). "Hypnosis and the perception of time". International Journal of Clinical and Experimental Hypnosis (International Journal of Clinical and Experimental Hypnosis) 27 (1): 29–41. doi:10.1080/00207147908407540. PMID 541126. Unknown parameter
- Campbell, LA and Bryant, RA (2007). "How time flies: A study of novice skydivers". Behaviour Research and Therapy 45 (6): 1389–1392. doi:10.1016/j.brat.2006.05.011.
- Stetson C, Fiesta MP, Eagleman DM (2007). "Does Time Really Slow Down during a Frightening Event?". PLoS ONE 2 (12). Bibcode:2007PLoSO...2.1295S. doi:10.1371/journal.pone.0001295.
- Marshall Barnes (2007). ""Does Time Slow Down During A Frightening Event?" Disproved.". AET RaDAL.
- Pastor MA, Artieda J, Jahanshahi M, Obeso JA (1992). "Time Estimation and reproduction is abnormal in Parkinson's disease". Brain: A Journal of Neurology 115 (1): 211–225.
- Davalos DB, Kisley MA, Ross GR (2002). "Deficits in auditory and visual temporal perception in schizophrenia". Cognitive Neuropsychiatry 7 (4): 273–282.
- Levy F, Swanson JM (2001). "Timing, space and ADHD: The dopamine theory revisited". Australian and New Zealand Journal of Psychiatry 35 (1): 504–511.
- Meck WH (1995). "Deficits in auditory and visual temporal perception in schizophrenia". Cognitive Brain Research 3 (1): 222–225.
- Sacks O (1973). Awakenings. Vintage Books. ISBN 0-375-70405-1.
- Levy F, Swanson JM (2001). "Timing, space and ADHD: The dopamine theory revisited". Australian and New Zealand Journal of Psychiatry 35 (1): 504–511.
- Simth A, Taylor E, Rogers JW, Newman S, Rubia K (2002). "Evidence for a pure time perception deficit in children with ADHD". Journal of Child Psychology and Psychiatry 43 (4): 529–542.
- Franck, Nicolas; Posada, Andrés; Pichon, Swann; Haggard, Patrick (2005). "Altered Subjective Time of Events in Schizophrenia". The Journal of Nervous and Mental Disease (Lippincott Williams & Wilkins, Inc.) 193 (5): 350–353.
- M. J. Waller; J. M. Conte, C. B. Gibson, M. A. Carpenter (2001). The effects of individual perceptions of deadlines on team performance (PDF). Academy of Management Review. Retrieved 2011-10-13.
Sources and further reading 
- Andersen, Holly, and Rick Grush, "A brief history of time-consciousness: historical precursors to James and Husserl", To appear in the Journal of the History of Philosophy.
- Le Poidevin, Robin, "The Experience and Perception of Time", The Stanford Encyclopedia of Philosophy (Winter 2004 Edition), Edward N. Zalta (ed.)
- Hodder, A. (1901). The adversaries of the sceptic; or, The specious present, a new inquiry into human knowledge. Chapter II, The Specious Present. London: S. Sonnenschein &. Pages 36 – 56.
|Wikibooks has more on the topic of: Time perception|
- Time perception research at the University of Manchester
- "A Cognitive Model of Retrospective Duration Estimations", Hee-Kyung Ahn, et al., March 7, 2006.
- "Time, Force, Motion, and the Semantics of Natural Languages", Wolfgang Wildgen, Antwerp Papers in Linguistics, 2003/2004.
- Can Time Slow Down?
- "Interactions emerge between biological clocks", The Pharmaceutical Journal, Vol 275 No 7376 p644, 19 November 2005 Registration required.
- Eagleman, David M.; Peter U. Tse, Dean Buonomano, Peter Janssen, Anna Christina Nobre, Alex O. Holcombe (November 9, 2005). "Time and the Brain: How Subjective Time Relates to Neural Time". The Journal of Neuroscience 25 (45): 10369–10371. Retrieved 2011-10-02.
- Slanger, Tom G. (1998). "Evidence for a Short-Period Internal Clock in Humans". Journal of Scientific Exploration 2 (2): 203–216. Retrieved 2011-10-02.
- LePoidevin, Robin (2007). The images of time: an essay on temporal representation. Oxford University Press. ISBN 0-19-926589-5.
- Time experience