The Power of Time Perception

by Jean Paul Zogby

  Recap

  In summary, psychedelic drugs that stimulate brain neurotransmitters, like LSD, marijuana, magic mushrooms (psilocybin), amphetamines (speed), or mescaline boost alertness and the speed of information processing, and slow down time, while depressant drugs that suppress these neurotransmitters appear to speed time up.

  In this chapter, we saw how drugs like marijuana, cocaine, and LSD increase levels of dopamine in the brain and enhance concentration and feelings of wakefulness. Smart drugs and cognitive enhancers have a similar effect on alertness and attention and, undoubtedly, slow the experience of time by accelerating the brain’s speed of processing information. Mental disorders, such as ADHD, Parkinson’s, and Schizophrenia, are also characterized by abnormal levels of neurotransmitters and these patients experience similar distorted time perception.

  In the first part of this book, we explored how we perceive time and the brain mechanisms involved in speeding it up or slowing it down. In the second part, we explored the factors that affect the perceived speed of time. These factors mainly affect the prospective time experience in the present, or what psychologists refer to as the experience of “time-in-passing.” We looked at the level of attention we devote to tracking time, our level of alertness and mental arousal, our emotions and unique personality traits, as well as the influence of drugs and mind enhancers. All of these factors speed up or slow down the perceived flow of time by influencing the speed of our thoughts—that is, the speed at which we perceive reality. The effects are either a stretching or shrinking of the duration of activity we are engaged in. It is all about the “experienced duration,” as it is unfolding now. But what about the experience of time in the past or in the future?

  How do we perceive the duration of events that are already part of the past, and which are later recalled? This could be a recollection of how long or short a vacation was, how long a meeting went on for, or how long a month or year seemed to last. Similarly, how do we anticipate the future and plan for things ahead of time? In the last part of the book, we will look at how we recall the duration of past events, and what causes those remembered events to stretch or shrink in our mind. This is essential to how we perceive the whole span of our life and is vital to our sense of satisfaction and fulfillment. It will also help us understand how we experience time when planning and anticipating the future and why time speeds up as we grow older.

  Part Three

  How Do We Perceive the Past and the Future?

  Chapter 10

  A Time to Remember

  Time Perception and Memory

  Life can only be understood backwards, but must be lived forwards

  ― Soren Kierkegaard

  Tin Box Memories

  How is it that some people can clearly recall detailed memories from their earliest childhood years, while most of us struggle to recover any recollections from that time? We all yearn to remember the things we did, the people we met, and the streets, houses, and playgrounds we grew up in. After all, the tiniest details of those significant events are a big part of our life story. But, as we grow older that time fades away, as if it was never part of our life. Those years are often distilled into only a few moments of memories. If we had the chance to go back in time and relive it once more, we would surely seize that opportunity to save every memory, every scrap of paper, every gift from a friend, and every moment of laughter. Brain scientists believe that our memories, though they may seem remote and ephemeral, are not lost but lie dormant deep inside our mind, waiting for the right moment to be re-awakened.

  One particular memory of great significance is our first and earliest childhood memory. Try to remember it as vividly as you can. Where were you? What were you doing? Who was with you? What happened in that moment? According to the great Austrian psychologist Alfred Adler, your first memory is a window into the rest of your life and it is the cornerstone upon which you build all of your personal memories. As such, it reveals a lot about how you turned out to be. The event that makes up your earliest memory may not be remembered accurately, and your mother may have told you that it did not really happen that way, but that makes no difference. What is important is how you remember it and what you believe was true. In fact, every time you remember something, you essentially recreate its details in your mind, changing it slightly in the process. Your memory is not like a hard disk that saves images that look exactly the same each time you access them. Every time you recall an experience from your past, you reconstruct and relive it and, in doing so, you unconsciously alter its content. If it was an unpleasant experience, you erase some of that negative sting and fill in the gaps with fabricated details. If it was a pleasant one, you add positive details to make it even more memorable and enjoyable. The result of such an emotional coping technique is that, when you look back over your life, you will likely perceive it to be more positive than negative.

  Your unique memories are crucial in shaping who you are. Thus your identity depends partly on all of those events, people, and places you can recall. The way you experience your past also affects your present thoughts, feelings, and actions. On a fundamental level, you are what you remember. This is also true on a cultural level for an ethnic group. Those who share a common past also share a common identity and culture.

  When we think back on our own past, we realize that it is made up of a series of mental snapshots starting from our earliest memories, through to the various defining moments in our life: the good and the bad, the happy and the sad, the mistakes we made, and the lessons we learned. We view our own lifetime and how long we have been living in terms of the number of unique memories that we have. The higher the number of memories, the longer we perceive our lifetime to be. It is important to be able to remember significant moments so that when we recall our past, we will be satisfied that we have lived a fulfilling life. Recalling a positive past is essential to our happiness and sense of well-being.

  Locating the Past

  The biggest problem with the past is that it is not easy to remember. First, you need to locate when an event has occurred in time. Then, you need to recall how long it took and what actually happened. Such assessments form the basis of many decisions you make in the present, even the relatively mundane ones. For instance, if you were trying to choose a restaurant for a dinner, you might want to know whether you recently had Japanese or Italian food. In deciding what to wear, you may look in your closet to determine which of two shirts you wore more recently. We are constantly trying to locate the timing and order of events from the past.

  If you were trying to locate an object in a room, you would normally use visual information, such as certain spatial reference points, to determine if that object is to the left or right, or whether it is high or low. However, when we are trying to locate an event from the past, things are more difficult since we do not have a solid coordinate system that we can navigate. So how does our brain encode memories with time? How do we know which of our memories are recent and which are from long ago?

  Our internal time coordinates are based on patterns of time, i.e. hours, days, weeks, months, and years. We relate events according to when they occur within these cycles. There are also major milestones in our lives that we tend to use as fixed reference points, e.g. the year we graduated from school, the date on which we got married or started our first job. Our brain reconstructs the timing of an event by estimating its distance from the present, comparing it to familiar time patterns, or associating it with events that directly succeed or precede it in time. We recall events from our memory by relating them to personal “landmarks,” such as “I was attending an annual party” or “It was within a few weeks of the birth of my first child.” 128 For example, you might recall that you got married in September 2001 (time location), which was 16 years ago (time distance), and that this was immediately after you joined a new company (relation to another event). This time information aids us in arranging our memories chronologically into an autobiographical story. />
  If you were an archeologist trying to establish the age of an ancient golden cup that had been discovered while digging in old ruins, the first thing you would do is determine the amount of time that has elapsed since that cup was made. You might use a carbon-dating technique and find that the cup was produced about 2,000 years ago. You might then search the cup’s surroundings for some clues to reveal its location in time and the era it had belonged to. Lastly, the features on the cup itself, such as carvings on its surface or the technology used to produce it, might give you a hint as to when it was created, relative to other contextual information. In the same way, our brain uses information about distance from the present, location in time, and relative time of occurrence to arrange the order of our memories in time. Our brains locate events in the past by using time information extracted from the memory content itself. We use the context in which a memory is recalled to judge the time in which it occurred. For example, if it is winter now and you have a mental snapshot of yourself wearing a swimsuit on a beach, your brain will assume that this memory is older than another memory snapshot where you are in a ski resort wearing heavy winter clothes.

  Moreover, our brains store memories by the order in which they occur. As it stores new memories, it pushes older ones further into the past. Therefore, the distance of an event in the present is directly related to its memory trace. The strength of a memory fades with time, so a stronger memory trace is judged by our brain to be more recent than a weaker one. Also, the more details you can remember from an event, the more recent it will seem. 129 Last night’s football game will seem more vivid than the game you saw last week. As time passes by, the unimportant details start to fade away, so that after, say, a month, if you try to recall which game occurred first, you will guess that it is the one about which you remember the least detail.

  Now, try to remember the name of one of your third grade teachers. You will find that a bit hard. How about any teacher from twelfth grade? That is likely much easier to recall since it is more recent. Now try recalling the name of any teacher from eleventh grade and keep going back until you reach third grade. By going backwards in time, grade by grade, you may actually be able to remember your third-grade teacher. That is what researchers found at the State University of New York when 161 students were asked to recall the name of one schoolteacher from each grade, first to twelfth. Some were asked to do it backwards, while others did it forwards, and still others were asked to recall these memories randomly. The results indicated that students answered faster and more accurately when they started with twelfth grade and moved backwards, than when they started with first grade and moved forward, or when remembered in a random order. 130 It turns out that backward search through long-term memory is more efficient than forward search. In the same way, if you try to recall what you did on your summer vacation four years ago, it will be easier if you started by listing the intervening vacations first. The reason for why we tend to remember things better when looking backwards in time is that recent memories are more accessible than distant ones and the context of one successfully retrieved memory facilitates the recall of the adjacent one. Of course there are several other ways to remember the past. I will not go into more details here, for there are excellent books that focus on memory improvement and enhancement. However, I will just mention one quick example here. The best way to remember your wedding anniversary or your wife’s birthday is to forget it once. Rest assured, that will be the last time you forget!

  Backward search through long-term memory is more efficient than forward search

  Remembered Durations

  Trying to work out when events have occurred in the past is only half the problem. Another issue is remembering how long they took. But when we recall the duration of something we did in the past, what is it that we are really remembering?

  One of the earliest, and most famous, answers to this question comes from St. Augustine in his book The Confessions, which contains a long and fascinating exploration of time and in which he raises the following conundrum:

  When we say that an interval of time is short or long, what is it that is being described as having a short or long duration? It cannot be what is past, since that has ceased to be, and what is non-existent cannot presently have any properties, such as being long. However, neither can it be what is present, for the present has no duration. In any case, while an event is still going on, its duration cannot be assessed. 131

  As you might have guessed, Augustine's answer to this puzzle is that when we guess the duration of an event, what we are measuring is actually in our memory. From this, he concludes that past and future exist only in our mind and that our perception of an event’s duration must somehow be related to an aspect of the memory from that event. So if you are trying to recall the duration of a movie you saw last night, or how much time it took you to finish a report last week, the interval itself does not exist anymore; what is left of it is only a memory trace.

  While engaged in such activities, you may not have been particularly aware of the passage of time and you only recall those durations after the fact. As we saw in Chapter 1, psychologists refer to this as “retrospective time experience” or “remembered duration.” A remembered duration can span an interval of a few seconds to, in principle, a whole lifetime. This is different from the “experienced duration” (prospective time experience) that we explored in the previous chapters, and which is related to the experience of time as it is passing “now.” As we saw, the “experienced duration” is influenced by factors such as our emotions, our alertness level, the degree of attention we devote to keeping time, and it also depends on some of our personality traits. In contrast, the “remembered duration” only exists in our memory and, as we shall see, its duration is only influenced by the number of memories we retain in our mind. This is why, in this chapter, you will notice that some of the time perception factors that we already covered seem to have a counter effect on remembered durations, as compared to experienced durations. The remembered duration of a past event does not always match the experienced duration of the present and we will shortly see why such mismatches occur. Let us first look at what makes a remembered duration seem long or short.

  We saw that the apparent speed of time is dependent on the brain’s information processing speed, that is, how much information our mind can absorb and store in memory in any given time interval. The more information there is, the longer a duration appears and the slower time seems to flow. A similar relationship exists between the information stored in our memory and the duration of remembered events. This has been explored by eminent psychologists and scientists since the 18th century, but it was psychologist Robert Ornstein who gave the research a great leap forward when he came up with the “storage size hypothesis.” In the 1960s, Ornstein conducted a series of experiments to understand the connection between the amount of information stored in our memory and our sense of time. 132 In some experiments, he asked volunteers to inspect several paintings, each with varying degrees of complexity, and then asked them to guess how long they spent examining the paintings. He found that those who saw the more complex paintings estimated longer durations compared to those who saw the simpler ones. Similarly, he played tapes with various sounds on them and then asked the volunteers to estimate the duration for which they had been listening. He found that volunteers who listened to tapes with layered sounds later estimated longer time durations compared to those who listened to tapes with very little sound on them. He concluded that the complexity and intensity of the information being processed and stored in the brain affects the perceived duration of remembered events. This is known as the “storage size hypothesis,” which states that when people are asked to recall the duration of something they did in the past, they examine the amount of memories stored from that period. The greater the number of snapshots and the more complex and intense the information being processed, the greater the memory storage required, and the longer that duration will see
m.

  Evidence for the role of memory in time perception comes from listening to music. What happens to time when you are listening to your favorite song? A couple of minutes of intent listening feels longer than usual. When the song is over, it feels like time slowed down. I remember my early experience with classical music, when I got hooked on Richard Wagner’s overture from The Mastersingers of Nuremberg. The piece is about 10 minutes long, but time appeared to halt with every note, so that when it was over it felt like half an hour had passed. Wagner’s orchestration is quite remarkable, with very complicated counterpoint melodies, layered on top of each other with colorful acoustic timbres, so the piece requires a lot of concentration. It is also made up of several musical motifs that segment the piece into a complex sequence of memory markers. We saw previously how music also raises the alertness levels, causing the experienced duration to stretch, as if the present has slowed down. Here, the level of complexity increases the amount of auditory information that is processed, causing the remembered durations to expand in our mind when later recalled. Capturing and storing complex and novel information causes remembered durations to appear longer.