再過兩個月我就26歲了。假設我能活到100歲，那我就已度過人生四分之一以上的時光。不知為何，我總設想自己能活到100歲，雖然可能也活不了那麼久。但假如我真能活到100歲，那麼26歲就是個新的里程碑，標誌著我已跨越人生第一個四分點，而正向第二個四分點邁進。

有人說，過了20歲，生命在心理上就已過去了一半。這表示隨著年紀增長，你對生命長度，或對時間生理性的主觀感受也越來越快。時間就像一個滾下山的雪球，以加速度往下直衝。

為什麼年紀越大，感覺時間過得越快呢？我想，部分的原因是因爲年紀越大，越難感受新刺激。小時候，一切經驗都那麼新奇。每天，大腦的感官和認知都接收到新刺激。當我們不斷學習新事物，並被新資訊與刺激轟炸時，會感覺時間過得特別慢。因爲大腦需要處理所有新資訊，這填滿了它的時空維度。此外，童年也充滿了「無聊時光」，比方說坐在教室裡，想著下課鈴何時才響，這時，時間就好像變慢了。童年生活比較少「例行公事」，較難以預測，這種不可預測性讓時間似乎慢了下來，因為大腦需要時間來應對處理新情況、新資訊。但長大後，生活充斥著一遍又一遍的「例行公事」，再也沒有新鮮事。當我們習於周遭的一切，時間就加速了。每天、每週、每個月差不多都一樣，難以區分，容易預測；我們失去了時間感，時間就這樣消溶在背景意識中。

你是否曾有這種經驗－行駛在一條沒走過的新道路上，你會覺得開往新地點的路程，好像比回程要長？我想新刺激與舊事物對照的概念也可以應用於此。當你開往一個新地點，周遭每個小細節都寫入大腦的記憶中，因爲大腦在新環境下，會自動變得更警覺，以避免可能發生的危險。而開在一條已經走過的路上，就沒那麼新奇了，大腦會比較放鬆，因為它知道這條路大概沒什麼危險，所以不用再處理已處理過的資訊。大腦是個高效能的器官，當它不需工作時，就會放鬆以節省卡路里和能量。當大腦放鬆，不再檢視周遭每個細節時，你就易於喪失時間感。我把生命中頭一二十年看成是開車往某個新目的地前去；說來有點悲哀，但如果我不持續經驗或學習新事物，找到新刺激，讓大腦忙於適應、處理新資訊，那麼餘生將會像是一趟回頭路－從已到達的目的地往回開。

所以，怎樣才能將時間之氈平順地鋪展開來呢？我認爲擴展生命最簡單的方法就是為大腦找到新體驗和刺激。移居新國度，或去一個你從沒到過的地方度假，定會放慢你的時間。假期的頭幾天，我總覺得時間過得慢一些，因爲我的大腦正在花時間處理所有的新資訊。其實只消從平凡的生命迴圈中設法擠出更多的新體驗和刺激，將注意力轉向世上每個小細節，更專注觀察我們的周遭環境即可。我們人類總是活在未來，是未來導向的動物。我們的頭腦不由自主地設想未來，而身體追隨在後。看電影時，我們常會預想故事的結尾，或考慮之後要吃什麼甜點。週間工作、上學時，總是期盼、計劃著週末的活動。這種未來導向的意識對我們來說，既是福氣，也是災禍。我們只要將意識投射到未來，就能輕鬆立定計劃，完成許多動物做不到的事，但這種未來導向的姿態，也讓我們付出不少代價，經歷許多苦難。因為我們的煩惱大多來自對未來的不確定、恐懼和擔憂。因此要讓時間慢下來，最簡單的方法就是將意識拉回當下。日常生活中有太多我們沒注意到的小事。我們選擇性的注意力會濾掉許多小細節，我隨時都能舉出上百個例子；但若能專注觀察這些小細節，就能讓時間慢下來…而我現在就打算這麼作。

In 2 months I will be 26, and suppose that I get to live until I am 100 years old, my life is more than a quarter of the way over. For some reason, I’ve always envisioned myself to live until the age of 100, even though I might not last that long. But if I do get to live for 100 years, 26 is a new landmark because I have surpassed the first quarter while marching on into the second quarter of my life. They say that after you reach the age of 20, your life is half way over psychologically. This means the duration of your life, or the visceral and the subjective perception you have of how much time has passed by, goes by quicker as we age.  Time is like a snowball that’s rolling down a hill, the more it travels, the faster it roll.

Why does time seem to accelerate as we age? I think part of the reason is because when we are older , we fail to be stimulated by new stimuli. When we are kids, everything we experience is new and novel. There are always new stimuli that are coming into our brains daily to stimulate our perception and cognition. When we are constantly learning new things and are bombarded by new information and stimuli, time seems to slow down due to the brain’s need to process all the new information that is filling up its spatial-temporal dimension. Also, when we are children, our lives are filled with “boring moments” that seem to slow time down, like the way you sit in classrooms and wonder when the bell is going to go off. Our lives are also less routine-like and more unpredictable, and with unpredictability, time seems to slow down due to the way the brain takes its time to respond to and process novel situations and information. But when we grow older, we tend to live our lives through routine after routine and that nothing seems new anymore. Time speeds up when we are more or less used to everything that is happening around us. When every day/week/month is indistinguishable from each other and as predictable as the next, we lose the sense of time as it disappears and dissolves in the back of our consciousness.

You know how when you drive down a new road, it always seems to feel like it takes longer to drive to the new destination than on the drive back? I think the same concept of new stimuli vs. old stimuli can be applied here. When you drive towards a new destination, every little thing around you is registered into your brain because your brain automatically becomes more alert during new situations in case there are dangers to be avoided.But the situation becomes less novel when you drive on a road that you’ve already driven on before; your brain relaxes because it knows that there is probably not going to be any danger, so it no longer needs to process all that information that it has already processed. The brain is an efficient organ, and when it doesn’t need to do any work, it relaxes in order to save calories and energy. When the brain relaxes and stops processing every little detail in the environment, you tend to lose the sense of time. I’m looking at the first couple of decades of my life like the drive TO the new destination, and it’s kind of sad to think this way, but the rest of my life is going to seem like a drive BACK from an arrived destination if I don’t continue to experience/learn new things and find new stimulants to keep my brain busy adapting and processing new information.

So how do you stretch time out like a blanket? I think the simplest way to extend our life is to find new experiences and new stimuli for our brain to process and adapt to. Moving to a new country or going on a vacation to a place you’ve never been before can certainly slow time down. During my vacation days the first few days always seem a lot slower because of all the new information that my brain is taking time to process. Or we can simply be more attentive to our present environments by squeezing more experiences and stimuli out of this mortal coil and pay attention to all the little details in the world. As humans we live in the future as future oriented animals. Our minds project themselves into the future automatically with our bodies playing catch-up. During a movie we are always thinking about the ending or the dessert we are having after the show. Or when we are working or going to school during the week we are always looking forward to or planning the weekend. This future oriented consciousness that we have is both a blessing as well as a punishment. We are able to plan things ahead and accomplish a lot of the things that animals fail to accomplish simply by projecting our consciousness into the future. But a lot of our misery also comes at the expense of this future-oriented attitude, as most of our worries are worries and fears about the events in the future and its uncertainties. So what we can do to slow down time is simply to try to unfold our consciousness back into the present. There are just too many things that we are not paying attention to in our everyday surroundings. I can name hundreds of things that my selective attention is filtering out at this given moment that I can be contemplating about to slow time down... and that is exactly what I am going to do now.