William Blake |
We know that physical time goes on regularly,
but inner time (our sensation
of the passage of time) is very
variable. The two times do not have to match. Sometimes, watching at our
inner time, a minute can look like hours, while in other cases the hours fly
away. An English poet, William Blake, expressed it well in a famous poem:
To see a World in a Grain of Sand
And a Heaven in a Wild Flower,
Hold Infinity in the palm of your hand,
And Eternity in an hour
(Auguries
of Innocence, 1803?)
There is a long
history of literary works, in which a character enters aesthetic or religious ecstasy,
or simply falls asleep, and on returning to reality discovers that many years
have passed, sometimes centuries. This subgenre (called by scholars sleeper legends) has representatives in many literatures. In Spanish
literature, it is reflected in the legend of the monk and the little bird,
associated with the monastery of Leire. In this legend, a monk who enters in
ecstasy while a bird is singing, discovers upon awakening that three centuries
have gone by. Among medieval French lays there is a legend about the knight
Guingamor, who arrived in a wonderful city and stayed there for
three days, but when he left, he found that three centuries had passed. And in
the United States literature we have the famous story by Washington Irving
titled Rip
van Winkle, whose protagonist falls asleep one night and wakes
up 20 years later.
Among the many cases
of optical illusions, there is one that perplexes researchers, which could shed
light on the differences between physical time and inner time. This is the Color
Phi experiment or phenomenon, which can be described thus:
A person is placed before a
screen, and a blue dot is lighted on the top. When that dot is turned off, the
screen is kept dark for 90 milliseconds. At the end of that time, a red dot is
lighted on the bottom of the screen. Those subjected to this experiment claim
to see a blue light dot that moves down across the screen, and towards the
middle of its path changes color suddenly and becomes a red dot.
This experiment
poses an important problem, as it seems to be opposed to causality, for the
color change from blue to red of the perceived light dot seems to take place
before the red dot is lighted on the screen. How does the eye know that the dot
will change color and position before it happens?
The philosopher
Daniel Dennett used this experiment to deny that there are specific areas of
the brain associated with each of our conscious experiences. In contrast,
Francisco F. Varela, in an
article published in 1999 in volume 879 of the Annals of the New York
Academy
of Sciences, draws a different conclusion, asserting that this experiment shows
that internal time is not isomorphic with physical time, that there are
actually two different types of time, and that there is no simple (linear)
correlation between them.
The Color Phi Experiment |
Varela argues that,
in the inner time of our perception, there are three different types of time
scales, different from physical time:
- The 1/10 scale, where basic
or elementary events take place, such as neuron discharge. This scale
influences the fusion interval
of perceptions, that is, the minimum temporal distance for two
independent events to be perceived as different. These intervals usually
fall between 10 and 100 msec.
- The 1 scale, which performs
the large-scale integration of perceived events and would not be addressed
by isolated neurons, but by assemblies of nerve cells.
- The 10 scale, which
corresponds to our descriptions and narrations.
Varela tries to
explain conscious perceptions as an emergent result of the action of those assemblies
of neurons, whose existence he postulates, and asserts that our experience of
inner time and the present time is linked to the 1 scale, the second one.
For me, on the other
hand, all this means that the question is still unripe, and that our
knowledge of the neural basis of conscious phenomena is very fragmentary and
enormously incomplete.
The same post in Spanish
Thematic thread on Time: Preceding Next
Manuel Alfonseca
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