View source for Time perception

{{ExpPsy}}
{{Expert}}


{{see also|Mental chronometry|Sense of time}}
[[File:LR22 Clock 1.png|thumb|257x257px]]
'''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.<ref>{{Cite journal |title=Selectivity of attention and the perception of duration |author=G Underwood, RA Swain |journal=Perception|year=1973 |doi=10.1068/p020101 |volume=2|pages=101 |pmid=4777562|issue=1}}</ref><ref>{{Cite journal |title=Attention and interference in prospective and retrospective timing |author=SW Brown, DA Stubbs |journal=Perception|year=1992 |pmid=1437469 |volume=21 |issue=4 |pages=545–57 |doi=10.1068/p210545}}</ref> Some researchers attempt to categorize people by how they differ in their perception of time (see "[[#Personality characteristics|Personality characteristics]]" below).

Pioneering work, emphasizing species-specific differences, was done by [[Karl Ernst von Baer]].{{Citation needed|date=April 2011}} 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.{{Citation needed|date=April 2011}} Work with animals conducted by [[Jakob von Uexküll]] included measurement of length of momentum in snails.{{Citation needed|date=April 2011}}


Even in the presence of timepieces, different individuals may judge an identical length of [[time]] to be passing at different rates.{{cn}} Commonly, this is referred to as time seeming to "fly" (a period of time seeming to pass faster than possible) or time seeming to "drag" (a period of time seeming to pass slower than possible). The psychologist [[Jean Piaget]] called this form of time perception "lived time."{{cn}} 

A form of temporal illusion verifiable by experiment is the [[kappa effect]],<ref name="Wada">Wada Y, Masuda T, Noguchi K, 2005, "Temporal illusion called 'kappa effect' in event perception" Perception 34 ECVP Abstract Supplement</ref> where the interval between two events is perceived differently by different observers.

Time also appears to pass more quickly as one gets older. [[Stephen Hawking]] suggests that the perception of time is a ratio: ''Unit of Time : Time Lived''.{{Fact|date=February 2008}} For example, one hour to a six-month-old person would be approximately "1:4032", while one hour to a 40-year-old would be "1:349,440". Therefore an hour appears much longer to a young child than to an aged adult, even though the measure of time is equal.

==Theories==
[[William J. Friedman]] also contrasted two theories for a sense of time:<ref>{{cite web|url=http://plato.stanford.edu/entries/time-experience|title=The Experience and Perception of Time|accessdate=2009-10-22}}</ref>
*'''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.

==Short-term==
Although the sense of time is not associated with a specific sensory system, the work of [[psychologist]]s and [[neuroscientist]]s indicates that human brains do have a system governing the [[perception]] of [[time]]<ref>{{cite web | url= http://www.unisci.com/stories/20011/0227013.htm | title= Brain Areas Critical To Human Time Sense Identified | accessdate= | author= | date= 2001-02-27 |publisher= UniSci – Daily University Science News}}</ref> 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 rhythm|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 [[Cerebral cortex|cortex]] entirely removed, which suggests it is a low level (subcortical) process.<ref>{{cite book |last= Mackintosh|first=N. J. |title=Animal Learning and Cognition |isbn=978-0-12-161953-4}}</ref><ref>{{cite journal |doi=10.1111/j.1460-9568.1989.tb00352.x |last1=Jaldow|first1=Eli J.|last2=Oakley|first2=David A.|last3=Davey|first3=Graham C. L. |pmid=12106131 |title=Performance of Decorticated Rats on Fixed Interval and Fixed Time Schedules |publisher=European Journal of Neuroscience |pages=461 |issue=5|volume=1 |journal=European Journal of Neuroscience |url=http://www3.interscience.wiley.com/journal/119443633/abstract|year=1989}}</ref>

===Specious present===
{{main|Specious present}}
The specious present is the time duration wherein a state of [[consciousness]] is experienced as being in the [[present]].<ref name="JamesW">James, W. (1893). [http://books.google.com/books?id=JLcAAAAAMAAJ The principles of psychology]. New York: H. Holt and Company. Page 609.</ref> The term was first introduced by the philosopher [[E. R. Clay]].<ref>Anonymous (E. Robert Kelly), ''The Alternative: A Study in Psychology''. London: Macmillan and Co.,
1882.</ref><ref name="Andersen">{{cite journal
  | author = Andersen, Holly
  | coauthors = Rick Grush
  | title = A brief history of time-consciousness: historical precursors to James and Husserl
  | version =
  | publisher = Journal of the History of Philosophy
  | date = pending
  | url = http://mind.ucsd.edu/papers/bhtc/Andersen&Grush.pdf
  | format = [[PDF]]
  | accessdate = 2008-02-02 }}</ref> and developed by [[William James]].<ref name="Andersen">{{cite journal  | author = Andersen, Holly  | coauthors = Rick Grush  | title = A brief history of time-consciousness: historical precursors to James and Husserl  | publisher = Journal of the History of Philosophy  | date = pending  | url = http://mind.ucsd.edu/papers/bhtc/Andersen&Grush.pdf  | accessdate = 2008-02-02 }}</ref> 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]].<ref>"The Specious Present: A Neurophenomenology of Time Consciousness." In Petitot, Varela, Pacoud & Roy (eds.), ''Naturalizing Phenomenology''. Stanford University Press.</ref> The experienced present is an interval; it is not a momentary instant except 'speciously'.

The concept was further developed by [[William James]].<ref name="Andersen" />  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.

==Long-term==
Psychologists assert that time seems to go faster with age, but the literature on this age-related perception of time remains controversial.<ref>{{cite book |title=Studies on the structure of time: from physics to psycho(patho)logy |chapter=Subjective Time Versus Proper (Clock) Time |editor1-first=R. |editor1-last=Buccheri
|editor2-first=V. |editor2-last=Di Gesù |editor3-first=Metod |editor3-last=Saniga |first1=Ronald P. |last1=Gruber |first2=Lawrence F. |last2=Wagner |first3=Richard A. |last3=Block |publisher=Springer |year=2000
|isbn=0-306-46439-X |page=54 |url=http://books.google.com/books?id=LMsDqsvcxckC}}, [http://books.google.com/books?id=LMsDqsvcxckC&pg=PA54 Extract of page 54]</ref> 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.<ref>{{cite web|url=http://www.newscientist.com/article/mg16422180.900-look-how-time-flies|title=Look how time flies . . . |last=Robert |first=Adler|accessdate=2009-10-22}}</ref> 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,<ref>[http://www.newscientist.com/article/mg15220571.700-why-time-flies-in-old-age.html New Scientist magazine: Why time flies in old age]</ref> 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).<ref>{{cite journal | title=It Seems Like Only Yesterday: The Nature and Consequences of Telescoping Errors in Marketing Research | publisher=Journal of Consumer Psychology | url=http://www.questia.com/googleScholar.qst;jsessionid=KgPbgnYGLQyyHQtdPQbVMGHm5wp3tr94mQLkBF4hTvYJ09dlJx5N!-1941634607!-2081211395?docId=77055094 }}</ref>

While the difference in age between an older and a younger person always remains the same, the [[ratio]] between the two ages decreases [[Exponentiation|exponentially]] over time. For example, if a 27-year-old woman gives birth to a child, the ratio between their ages at the first day is about 10,000 to one. After a year, this decreases quite dramatically to only 28 to one. A decade later, the ratio is about 3.5 to one, and if the mother is alive at age 90, it is down to 1.4 to one. Regardless of the numerical difference in age, over time a younger person "catches up" to an older person by the [[power of two]]. (This can be proved mathematically by taking the [[partial derivative]] of the older person ''P<sub>1</sub>'' divided by the younger person ''P<sub>2</sub>''.)

It has been proposed that the subjective experience of time changes with age due to changes in the individual's biological makeup.<ref>{{cite journal | url=http://upload.wikimedia.org/wikipedia/commons/f/f1/SVUAging.pdf | title=Aging and the subjective sense of time | author= Svetlana V. Ukraintseva | year=2001 | journal=Current Concepts in Experimental Gerontology}}</ref> The apparent speeding up of time as we grow older is depicted in the [[Time's Paces]] poem of [[Henry Twells]] as modified by [[Guy Pentreath]]: "For when I was a babe and wept and slept, Time crept."

==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<ref name="Wada">Wada Y, Masuda T, Noguchi K, 2005, "Temporal illusion called 'kappa effect' in event perception" Perception 34 ECVP Abstract Supplement</ref> 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.


===Time in altered states of consciousness===
Altered states of consciousness are sometimes characterized by a different estimation of time. Some psychoactive substances – such as [[entheogen]]s – may also dramatically alter a person's temporal judgement. When viewed under the influence of such substances as [[LSD]], [[psychedelic mushrooms]] and [[peyote]], a clock may appear to be a strange reference point and a useless tool for measuring the passage of events as it does not correlate with the user's experience.  At higher doses, time may appear to slow down, stop, speed up, go backwards and even seem out of sequence. A typical thought might be "I can't believe it's only 8 o'clock, but then again, what does 8 o'clock mean?" As the boundaries for experiencing time are removed, so is its relevance. Many users claim this unbounded timelessness feels like a glimpse into spiritual infinity. To imagine that one exists somewhere "outside" of time is one of the hallmark experiences of a psychedelic voyage.{{Fact|date=February 2008}} [[cannabis (drug)|Marijuana]], a milder psychedelic, may also distort the perception of time to a lesser degree.<ref>{{cite web |url=http://www.erowid.org/plants/cannabis/cannabis_effects.shtml |title=Cannabis Effects |accessdate=2008-02-15 |work=Erowid |quote=Time sense altered: cars seem like they are moving too fast, time dilation and compression are common at higher doses.}}</ref>

The practice of [[meditation]], central to all Buddhist traditions, takes as its goal the reflection of the mind back upon itself, thus altering the subjective experience of time; the so called, 'entering the now', or 'the moment'.{{Fact|date=February 2008}}

===Psychoactive substances===
Psychoactive drugs can alter the judgement of time. Some – such as [[entheogen]]s – 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 1955, British MP [[Christopher Mayhew]] took [[Mescaline|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".{{Citation needed|date=April 2011}}

[[Stimulants]] can lead both humans and rats to overestimate time intervals,<ref>{{cite journal |quotes= |last=Wittmann |first=M. |coauthors=Leland DS, Churan J, Paulus MP. |date=8 October 2007|title=Impaired time perception and motor timing in stimulant-dependent subjects |journal=Drug Alcohol Depend. |volume=90 |issue=2–3 |pages=183–92 |pmc=1997301 |doi=10.1016/j.drugalcdep.2007.03.005 |pmid=17434690 }}</ref><ref>{{cite journal |last=Cheng |first=Ruey-Kuang |coauthors=Macdonald, Christopher J.; Meck, Warren H. |year=2006 |title=Differential effects of cocaine and ketamine on time estimation : Implications for neurobiological models of interval timing |journal=Pharmacology, biochemistry and behavior |volume=85 |issue=1 |pages=114–122 |pmid=16920182 |doi=10.1016/j.pbb.2006.07.019 |url=http://cat.inist.fr/?aModele=afficheN&cpsidt=18303059 }}</ref> while [[depressants]] can have the opposite effect.<ref>{{cite journal |last=Tinklenberg |first=Jared R. |coauthors=Walton T. Roth1; Bert S. Kopell |year=1976 |month=January |title=Marijuana and ethanol: Differential effects on time perception, heart rate, and subjective response |journal=Psychopharmacology |volume=49 |issue=3 |pages=275–279 |pmid=826945 |doi=10.1007/BF00426830 |url=http://www.springerlink.com/content/q1227453r481x439/}}</ref> The level of activity in the brain of [[neurotransmitters]] such as [[dopamine]] and [[norepinephrine]] may be the reason for this.<ref>{{cite journal |last=Arzy |first=Shahar |coauthors=Istvan Molnar-Szakacs; Olaf Blanke |date=2008-06-18 |title=Self in Time: Imagined Self-Location Influences Neural Activity Related to Mental Time Travel |journal=The Journal of Neuroscience |volume=28 |issue=25 |pages=6502–6507 |pmid= 18562621|doi=10.1523/JNEUROSCI.5712-07.2008 |url=http://www.jneurosci.org/cgi/content/abstract/28/25/6502 |accessdate=2008-08-25}}</ref>

===Altered states===
[[Hypnosis]]<ref>{{Cite journal |url=http://www.informaworld.com/smpp/content~content=a790232921~db=all |title=Hypnosis and the perception of time |publisher=International Journal of Clinical and Experimental Hypnosis |volume=27 |issue=1 |date=January 1979 |pages=29–41 |doi=10.1080/00207147908407540|author=Bowers, Kenneth |journal=International Journal of Clinical and Experimental Hypnosis |pmid=541126 |last2=Brenneman |first2=HA |unused_data=Author+Kenneth S. Bowers,Heather A. Brenneman}}</ref> and emotional state<ref>{{cite journal | journal=Behaviour Research and Therapy | volume=45 | issue=6 | year=2007 | pages=1389–1392 | author=Campbell, LA and Bryant, RA | title=How time flies: A study of novice skydivers | doi=10.1016/j.brat.2006.05.011}}</ref> 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.<ref>{{cite journal | author=Stetson C, Fiesta MP, Eagleman DM | year=2007 | title=Does Time Really Slow Down during a Frightening Event? | journal=PLoS ONE | volume=2 | issue=12 | doi=10.1371/journal.pone.0001295|bibcode = 2007PLoSO...2.1295S }}</ref> However, this experiment has been extensively critiqued.<ref>{{cite web | title="Does Time Slow Down During A Frightening Event?" Disproved. | author=Marshall Barnes | year=2007 | publisher=AET RaDAL | url=http://aet-radal.blogdrive.com/}}</ref>{{verify credibility|date=September 2012|reason=this is a blog -- by a guy who claims to have invented warpdrive, a cloaking device (sans device), and a time machine (sans device) - and several sites connected to him are listed as dangerous by McAfee}}

===Clinical disorders===
The sense of time is altered in some people with neurological diseases such as [[Parkinson's disease]] and [[attention deficit disorder]].{{Citation needed|date=February 2011}}

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.<ref name="ReferenceA">{{Cite journal|last1=Franck| first1=Nicolas| last2=Posada| first2=Andrés| last3=Pichon| first3=Swann| last4=Haggard| first4=Patrick|year=2005|title=Altered Subjective Time of Events in Schizophrenia|journal=The Journal of Nervous and Mental Disease|volume =193|issue=5|pages=350–353|publisher=Lippincott Williams & Wilkins, Inc.}}</ref> 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. According to an article titled ''Altered Subjective Time of Events in Schizophrenia'', in the Journal of Nervous and Mental Disease in 2005 (Volume 193(5), May 2005), researchers suggest that "abnormal timing judgment leads to a deficit in action attribution and action perception."<ref name="ReferenceA"/>

==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-[[personality psychology|personal]] characteristics and by external-[[social environment|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.<ref name="Waller">{{cite journal
  | author = M. J. Waller
  | coauthors = J. M. Conte,  C. B. Gibson, M. A. Carpenter
  | title = The effects of individual perceptions of deadlines on team performance
  | version =
  | publisher = Academy of Management Review
  | year = 2001
  | url = http://web.gsm.uci.edu/~cgibson/Publication%20files/Articles/The%20Effect%20of%20Individual%20Perceptions.pdf
  | format = [[PDF]]
  | accessdate = 2011-10-13 }}</ref> These axes typically create four personalities that differ in their personal characteristics and the way they deal with tasks.

'''[[Time perspective]]''' can be affected by [[genetics]], [[culture]], [[religion]], arise from [[education]], [[family]], past [[employment]], and so on. As it is well known, the timeline axis moves between past, present and future, which is also the way the time perspective axis is organised. People with a '''present perspective''' of time have a tendency to believe that the actions in the present do not significantly affect the future. That is, these people do not think that an action performed in the present will increase the probability of a future outcome. People with this perspective tend to use the phrase "why do today what can be done tomorrow?" Individuals with personality characteristics of present time perspective tend to think that it is unnecessary to make future plans. These individuals also tend to take risks and act impulsively. People with '''future perspective''' tend to believe that an action performed in the present increases the probability of a future outcome. These people are very goal-oriented, with high capacity to infer future results, usually prepare task lists, use a calendar, and tend to wear a watch. When a team is assembled from the majority of future time perspective people, the team tends to be more "flexible" and tends to make more changes in strategic thinking than teams with more present time perception individuals.<ref name=Zimbardo>Zimbardo, P.G., & Boyd, J.N., 1999. Putting time in perspective: A valid, reliable, individual-differences metric. Journal of personality and Social Psychology, 77: 1271–1288.</ref> Such an individual will delay his or her performances to the very last moment, which can at times lead to inability to meet deadlines. When such a person belongs to a work team, he/she makes the team less focused strategically, being late in submitting tasks and acting impulsively.

'''Time urgency''' relates to the need for quick response or action, to achieve a particular goal (or non existence of this feeling). It can be described as an axis ranging from '''high''' to '''low.'''<ref name="Waller"/>

The two dimensions described above produce four types of personalities, that can be described as follows:

'''Organizers''' have high time urgency and future time perspective and are characterized by high awareness of time, scheduling tasks and activities and high achievement striving.<ref name="Waller"/>

'''Crammers''' have high time urgency and present time perspective and are characterized by high awareness of time, needing to exert control over deadlines, competitiveness, high achievement striving and impatience.<ref name="Waller"/>

'''Relators''' have low time urgency and present time perspective and are characterized by attending little to deadlines or passage of time, taking risks, acting impulsively, focusing on present tasks and focusing on relations with others.<ref name="Waller"/>

'''Visioners''' have low time urgency and future time perspective and are characterized by attending little to deadlines or passage of time, taking risks, acting impulsively and focusing on future goals.<ref name="Waller"/>

===Culture===
Culture is another variable contributing to the perception of time. Anthropologist [[Benjamin Lee Whorf]] reported after studying the [[Hopi]] cultures that: "… the Hopi language is seen to contain no words, grammatical forms, construction or expressions or that refer directly to what we call “time”, or to past, present, or future…"<ref>Carroll, John B. (ed.)(1956). ''Language Thought and Reality. Selected Writings of Benjamin Lee Whorf''. MIT Press, Boston, Massachusetts. ISBN 0262730065 9780262730068</ref> Whorf's assertion has been challenged and modified. Pinker debunks Whorf's claims about time in the Hopi language, pointing out that the anthropologist Malotki ([[1983]]) has found that the Hopi do have a concept of time very similar to that of other cultures; they have units of time, and a sophisticated calendar.<ref>{{Citation | last = Parr-Davies | first = Neil | author-link = | title = The Sapir-Whorf Hypothesis: A Critique | publisher = [[Aberystwyth University]] | date = April 2001 | year = 2001 | url = http://www.aber.ac.uk/media/Students/njp0001.html | accessdate = [[2008-02-02]] }}</ref>

==See also==
*[[Benjamin Libet]]
*[[Chronemics]]
*[[Chronostasis]]
*[[Cognitive tempo]]
*[[J. M. E. McTaggart]] and his book [[The Unreality of Time]]
*[[Time#Judgement of time|Judgement of time]]
*[[Polychronicity]]
*[[Slow Motion Perception]]
*[[Tempo]]
*[[Time discipline]]
*[[Time estimation]]
*[[Time management]]
*[[Time perspective]]

==References==
<references/>

==References & Bibliography== 
==Key texts==          
===Books===

===Papers===
 
==Additional material==
===Books===

===Papers===
*[http://scholar.google.com/scholar?sourceid=mozclient&num=50&scoring=d&ie=utf-8&oe=utf-8&q=Time+perception Google Scholar]

==External links==
* [http://www.primitivism.com/time.htm Time and Its Discontents]
* [http://mixingmemory.blogspot.com/2004/12/by-request-time-perception-i.html Time Perception I] and [http://mixingmemory.blogspot.com/2004/12/time-perception-ii-cognitive-factors.html II]
* [http://manchestertiming.co.uk/ Time Perception Research at the University of Manchester]


[[Category:Perception]]
[[Category:Time perception]]

{{enWP|Time}}