Why is life accelerates with age

 Why for the elderly, time flows slower than for the young, and during accident events begin to happen in slow motion.

 Roman philosopher Seneca said: "Only time is ours" — and was absolutely right. With him will agree psychologists, because the time for the man himself is a subjective feeling and depends on the condition of the subject. 

 With age, we think that time goes faster in my childhood one hour may seem an eternity, but in his old age the years fly by with insane speed — no time to look at how the children have grown up, finished school, University and work. Of course, the passage of time objectively does not change.

However, the feeling that time is speeding up over our life is not pure and our prejudice, and has a very credible scientific explanation.

Scientists have determined that subjective time accelerates with the value of the square root of age. So for a 40-year-old adult one year is two times faster than for 10-year-old child. Given this pattern, it can be considered equal to the following four periods in life: 5-10 years (1×), 10-20 years (2×), 20-40 years (4×), 40-80 years (8×).

The most common explanation for the phenomenon lies in the fact that the majority of feelings for the child are new, while for adults this sensation has happened several times in the course of life. Children should be as involved in what is happening at the moment and dedicate enough of their brain resources, because they need to constantly rebuild their mental models of the world for the normal adaptation and appropriate behavior. In contrast, adults rarely go beyond their familiar tasks and routines. When the brain is often faced with the same stimulus, the latter becomes "invisible" to us, because he has already effectively entrenched in the memory and it needs much less resources — this is called neural adaptation. During periods of part time engagement in the moment in memory is less rich parts of memories, which time seems to have passed very quickly. 

 There is another, more physiological, explanation.

Throughout life, the brain changes the content of neurotransmitters intermediaries in the transmission of signals between neurons.

With age decreases the level of dopamine modulation of working of the basal nuclei of the subcortical brain structures associated with the regulation of motor functions and attention involved in the reinforcement system, but also the internal clock of the brain that measure intervals from a few seconds to several minutes. Drugs that inhibit the dopamine system, have the effect, in which the internal clock of the brain have been slower, resulting in a person underestimates the duration of any time interval. In the experiments of Peter Mangan, a psychologist from the College of the University of Virginia in Wise (The University of Virginia's College at Wise), compared the ability to estimate the interval in 3 minutes, have two groups of people: young (19-24 years) and elderly (60-80 years). When the subjects reported that it took 3 minutes in the young group on average took 3 minutes and 3 seconds, while the older group took 3 minutes and 40 seconds.

In addition to age on the perception of time is also influenced by other factors. For example, when the temperature of the body while subjectively faster, and lowering it slows down. The experiment was conducted by the Estonian scientists in 20 men has revealed that after one hour of exercise on a treadmill under conditions of high temperature playback time intervals of the subjects had previously marked the end of the specified interval, than before training. The study authors explain this effect by increasing the level of wakefulness during exercise. However, after 10 days of acclimatization to high temperature occurred physiological adaptation, and reproduction of intervals returned to the level before exercise. 

 Important role in the evaluation of the flow of time is difficult. Moreover, the greatest effect on the perception of time is having a sense of fear.

Being in extreme situations, for example during a car accident, some people report that time seems to have stopped and the picture before my eyes passed in slow motion.

While the person can remember every detail at this moment, reached the maximum concentration. In the novel by Fyodor Dostoyevsky "the Idiot" quite vividly described the state of the offender is sentenced to death, who, being on the scaffold going crazy with fear and horror in the face of death:

Think about it: if, for instance, torture; the suffering and wounds, bodily flour, and, therefore, mental suffering distracts so one only wounds and tormented, all the way until they die. But the chief, the strongest pain may not be in the wounds, but that you know for certain that here in an hour, then ten minutes, then after half a minute, then now, now — the soul will leave your body, and that man will no longer be, and that is certain; it's what I think. Here's how the head put under the knife and hear him slipnet over my head, these a quarter of a second only and worse.

The less emotional a person is, the more precisely it defines a specified time. The most accurate chronometers of people is depressive patients. In a study conducted by a group of scientists from the University of Hertfordshire in the UK, it has been shown that people with a mild form of depression have so-called "depressive realism": they are less focused on the external factors that can distort their judgments about time, and thereby more accurately determine the past time intervals, than people without depression, usually reevaluates the amount of time elapsed. 

 But even the finest people-timepieces incredibly easily susceptible to temporary distortion of perception. It is known that the signals from the different analyzers are in the brain at different speeds. When the world just appeared the TV, was still unsolved the problem of synchronization of audio and video signals: they separated for 100 milliseconds, while the man did not notice this.

If anyone touches the little finger of your foot to the tip of the nose at the same time, you will not feel any delay while the signal from the nose comes to the brain faster than on foot.

How is the brain able to piece together the information coming asynchronously from different senses, and place it in the correct order? Finding answers to these questions engaged the American neuroscientist David Illman (David Eagleman). His theory States that when integrating information from the senses, the brain is guided by the principle of expectation the slowest signal. Thus it turns out that our consciousness is always living somewhat in the past.

It's like a live TV broadcast when the signal from the scene to the TV comes with a pretty big delay, especially if the video stream is subjected to a parallel installation.

In order for each moment observed the correct chronological order of events, the brain all the time precalibrated the arrival time of the signals, so if you're up to something touch, the feeling of contact coincides with the motor act. However, this mechanism can be outmaneuvered. If a person is allowed to press the button, and after pressing for some time to submit flash of light, but not immediately, but with some slight delay, after removal of delays will be the primary inversion of the chronological order between the action and the feeling after him: the man seemed that the light illuminates before pressing the button.

Of great interest are the extraordinary failures in the perception of time in patients with brain aneurysm and epileptics. For example, one of the patients neurologist Fred OSU (Fred Ovsiew) from northwestern University, Chicago time suddenly stopped. It all started with a headache, hoping to ease the patient went to take a warm shower, when he noticed that he could see every drop falling, they all seemed frozen in the air.

After going to the doctor he was found to have an aneurysm.

In another case in Japan, 59-year-old man, who suffers from epilepsy, told me that when talking to someone it seemed to him that the facial expressions of the interlocutor is not synchronized with his speech. Such a violation of the perception of motion in neurology is called akinetopsia and mediotemporal is caused by damage to secondary visual cortex, located in the middle temporal gyrus. This region, along with the primary visual cortex is also involved in encoding time. A study conducted at the University hospital of Lausanne in Switzerland, showed that the impact of transcranial magnetic stimulation on these visual areas of the brain more difficult subjects were able to determine two time intervals, which one was longer.

Further study of the perception of time can change our view of the concept of time. If it (to paraphrase the aphorism of Seneca) really belongs to us is only a construction of consciousness, as well as the color, it is possible that in the future we will be able to more objectively define this concept in physics and philosophy, freed from subjective prejudice. 

The science Department "Газеты.Ru"