Human eyes have constant breaks in perception whenever they flit about, in blind jumps called saccades. To experience this temporary blindness, look at your own eyes in a mirror and shift your sight focus from one eye to the next. Although a person standing next to you and watching you will effortlessly see your eyes flit and shift from one direction (line of sight) to another, you will never be able to see your own eyes move - even though they do move and are indeed seen as such by the other person. This blindness is due to the saccades.
Almost everyone has had the slightly odd experience of looking at their watch, and believing that the watch had stopped. Then, after a perceptibly longer time than a second , the seconds hand of the watch (or its digital display) starts moving again and all subsequent measured seconds last for, well, a second.
This well known effect happens because the brain fills backwards in time the period of time when it was blind with more of the same, to wit, with the image it saw first when the cascade ceased. So far, so good, although we can wonder at how the brain can fill time backwards in our perception. But at least this is an explanation that only involves our brain and our perceptive skills.
And then this explanation breaks down, because of something called the dead phone illusion. It's a like effect that can happen when picking up a telehone handset with an intermittent dial tone (pause/tone/pause/tone …): The first pause seems longer than the subsequent ones, and the explanation by saccadic eye movement does not apply.
Yarrow et al. have investigated further reproducible kindred cases, such as when tactile perception actually precedes the time of actual physical contact, and so on.
An ultimate explanation for chronostasis - when time stands still - is still elusive. Do you have a favored theory?
I'm not sure you have understood the question Joachim. None of these papers even remotely addresses the question.
Well, I do not have myself an explanation.
But there is a few works known to me on this matter:
Vision Res. 2013 Feb 28;83C:56-65. doi: 10.1016/j.visres.2013.02.013. Spatio-temporal topography of saccadic overestimation of time. Knöll J, Morrone MC, Bremmer F.
They conclude "We show that chronostasis occurs across the visual field with a clear spatio-temporal tuning. Furthermore, we report chronostasis during simulated saccades, indicating that spurious retinal motion induced by the saccade is a prime origin of the phenomenon."
J Exp Psychol Hum Percept Perform. 2008 Feb;34(1):125-36. doi: 10.1037/0096-1523.34.1.125. Taking a long look at action and time perception. Hunt AR, Chapman CS, Kingstone A.
They conclude "the experiments reported here suggest that distortions of time perception related to an eye movement are not distinct from temporal distortions for other kinds of responses. Moreover, voluntary action is neither necessary nor sufficient for overestimation effects. These results lead to a new interpretation of chronostasis based on the role of attention and memory in time estimation."
Exp Brain Res. 2007 Jul;180(3):535-9. Epub 2007 Feb 8. Spatio-temporal contingency of saccade-induced chronostasis. Georg K, Lappe M.
They conclude "This result suggests a local, object-specific mechanism underlying the stopped clock illusion that might originate from a shift in attention immediately preceding the eye movement."
Exp Brain Res. 2005 Feb;161(1):125-32. Epub 2004 Dec 7. Chronostasis without voluntary action. Alexander I, Thilo KV, Cowey A, Walsh V.
They conclude "these findings suggest that the mechanisms underlying chronostasis are best explained by an arousal hypothesis since neither attention nor backdating to action can account for the commonalities between chronostasis in the auditory, visual and tactile domains."
Conscious Cogn. 2004 Jun;13(2):373-90. Action, arousal, and subjective time. Yarrow K, Haggard P, Rothwell JC.
They conclude "Results indicated that the chronostasis effect is constant across a wide range of stimulus durations and does not reflect the pattern of visual stimulation experienced during a saccade, suggesting that arousal is not critical. Instead, alternative processes, such as one affecting the onset of timing (i.e., the time of internal clock switch closure) are implicated."
J Cogn Neurosci. 2004 Jun;16(5):839-47. Consistent chronostasis effects across saccade categories imply a subcortical efferent trigger. Yarrow K, Johnson H, Haggard P, Rothwell JC.
They conclude "it is suggested that chronostasis is triggered by a low-level signal arising in response to efferent signals generated in the superior colliculus."
Curr Biol. 2003 Jul 1;13(13):1134-9. Manual chronostasis: tactile perception precedes physical contact. Yarrow K, Rothwell JC.
They conclude "The illusion's magnitude suggests backward extrapolation of tactile perception to a moment during the preceding reach. The illusion does not occur if the arm movement triggers a change in a continuously visible visual target: the time of onset of the change is estimated correctly. We hypothesize that chronostasis-like effects occur when movement produces uncertainty about the onset of a sensory event. Under these circumstances, the time at which neurons with receptive fields that shift in the temporal vicinity of a movement change their mappings may be used as a time marker for the onset of perceptual properties that are only established later."
Exp Brain Res. 2003 Apr;149(4):527-9. Epub 2003 Feb 26. Voluntary action expands perceived duration of its sensory consequence. Park J, Schlag-Rey M, Schlag J.
They conclude "These results indicate that the illusion of chronostasis is not specific to saccadic eye movement, and may therefore involve a more general mechanism of how voluntary action influences time perception."
Curr Biol. 2002 Oct 15;12(20):1779-81. Auditory chronostasis: hanging on the telephone. Hodinott-Hill I, Thilo KV, Cowey A, Walsh V.
They conclude "We suggest that this generalization of chronostasis to another sensory system is consistent with theories of time perception that emphasize a single, multimodal clock for duration estimation rather than a mechanism that is dependent on motor acts."
Nature. 2001 Nov 15;414(6861):302-5. Illusory perceptions of space and time preserve cross-saccadic perceptual continuity. Yarrow K, Haggard P, Heal R, Brown P, Rothwell JC.
They conclude "We suggest that temporal extension of the target's percept is one of the mechanisms that 'fill in' the perceptual 'gap' during saccadic suppression. The effect is critically linked to perceptual mechanisms that identify a target's spatial stability."
Hope it helps
As you said "an ultimate explanation for chronostasis - when time stands still - is still elusive."
Further, I add it seems that very few groups actually approach this topic (I only know 5 groups with Yarrow's being the most active one).
To your specific question "Do you have a favored theory?", I must say I tend to follow the conventional thought "latest science holds better for a while", and that the recent works by Knöll et al seem well sound to me.
Samuel,
Thanks for the response, I was aware of most but not all these papers.
Some are mutually contradictory, and most are really not quite convincing enough - for instance, I find Knöll's spurious retinal motion a total nonstarter (partly because non visual, hence non retinal saccade equivalents exist, and partly because even if non visual equivalent explanations could be devised they still would not provide a sufficient explanation for the phenomenon)
I believe that the explanation lies in the processing by the brain, not in the 'signal capture' or the data acquisition sensors, be they the eye or another sense. The processing might yield the observed outcome in a number of quite different ways
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