I slumped in a wheelchair in my doctor’s office. The clock above the door ticked erratically, as if someone outside the room was winding the gears forward and then turning them back every few seconds. The words Dr. W spoke seemed to fall from her mouth, then slowly float across the room one by one. To my ears, her speech was devoid of any cadence. Unable to hear the pauses that indicated the ends of her sentences, I kept interrupting her.
A month before this doctor’s appointment, lupus, the chronic autoimmune disease I had lived with for the past four years, had spiraled out of control. In rare cases like mine, lupus can cause severe brain inflammation called lupus cerebritis. I’d first realized I was seriously ill when I stood up after teaching a violin lesson and forgot how to walk. My legs didn’t hurt — they simply refused to lift from the floor.
Over the next few weeks, my brain quickly unraveled, despite the high doses of immunosuppressants and IV steroids my doctor prescribed. I lost sensation in my left arm. I forgot that my favorite color was red and even whether or not I liked yogurt. I no longer remembered telling ghost stories around a campfire with my family as a child or the day I left for college. My emotions vacillated from fury to giddiness to crushing depression on an hourly basis. I hallucinated fireworks onto my bedroom ceiling and stared as the air around me appeared to ripple like water. Due to problems with my short-term memory, I repeated myself over and over — that is, when I remembered enough of my vocabulary to actually speak.
Unable to walk, communicate or think coherently, I lay in bed for months, wondering if my mind would ever be the same. But as a classically-trained string musician, one of the cognitive abilities I grieved the most was my ability to comprehend time.
Due to problems with my short-term memory, I repeated myself over and over — that is, when I remembered enough of my vocabulary to actually speak.
At the core of any orchestra or string quartet is synchrony: a diverse, often eclectic mix of individuals with the finely-tuned ability to play in time with each other, to move together, and even to breathe together. An orchestra of well-trained musicians can accelerate the tempo or slow it down, pause to let a beautiful chord ring throughout a concert hall, then restart exactly together. When each instrument in an orchestra plays precisely in time with each other, the result is a seemingly effortless command of time that can only be achieved through many years of rigorous study.
I had fallen in love with the viola as an elementary school student. Over many hours of private lessons, orchestra rehearsals and practice, I’d built my career as a professional musician. That the many years I’d spent honing my skill as a musician could vanish in a month terrified me.
Whether we’re managing a demanding career, caring for children, or both, most of us have dreamt of not being bound to the metaphorical hourglass through which our day seems to slip. But what we actually want is more time, not the absence of time altogether. Being unaware of the passage of time felt like being trapped in a single chaotic moment that never ends. I had no way of knowing how long I’d been sick for, when my caretakers would bring me dinner, or how long my recovery might take. Without a sense of time, seconds stretched indefinitely into the future. When I asked my caretakers for food or coffee, they seemed to disappear for hours before they returned.
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In addition to my difficulty perceiving short spans of time, my comprehension of longer periods of time was also affected. I referred to every past event in my life, whether it was my doctor’s appointment the day before or an audition I’d taken years ago, as having happened “yesterday.” I couldn’t remember what date, month or even year it was. I forgot what times of day were appropriate to call friends and family on the phone, and I didn’t understand what people meant when they said they were “busy.” Bedridden and unable to comprehend time, my illness seemed to drag on for eternity with no end in sight.
Even while bedridden, I tried to piece together the meaning behind my brain’s dysfunction. Learning about neuroscience helped me come to terms with my disease. I learned that no one area of the brain is solely responsible for measuring time. Rather, “the entire brain is critically dependent on the timing of neural transmissions throughout,” explains Dr. Alan Brown, former chair of psychology and associate dean of the College of Arts and Sciences at Southern Methodist University. “The information that we receive from the outer world is sent through our neurons in waves or pulses, and this is how the brain processes everything (the smell of a rose, the color red, a rough touch). So, literally, we have several trillion small temporal processing units in our brain.”
"The entire brain is critically dependent on the timing of neural transmissions throughout."
Unlike more concrete and specific brain functions with designated areas within the brain, like our sense of smell, sight or touch, the brain’s perception of time is abstract. A combination of external input (like seeing the streetlights outside our house flick on), internal sensory input (like feeling tired), and memory (like groaning when we remember we have an early work meeting ) might lead our brains to determine that it’s time to go to bed.
“Most recent brain research has found that the brain is a lot less localized than we previously thought. That is, a specific piece of information (i.e., your grandmother’s face) does not reside in a precise location in the brain, but may involve tens of thousands of different small processing sites throughout the brainstem and cortex,” says Dr. Brown.
A 2020 report in the Journal of Neuropsychiatry cites meta-analysis of MRIs and PET scans in determining the collaboration between different areas of the brain in processing time. “These studies support the presence of a widespread network of cortical and subcortical areas that are variably recruited based on specific task parameters and demands,” the authors write.
Neuroscientists have long known that the human brain is capable of measuring units of time under ten seconds more or less accurately due to a group of time-keeping cells in the hippocampus. But in a 2018 study published in the journal Nature, researchers at Norwegian University of Science and Technology’s Kavli Institute for Systems Neuroscience believe they made a breakthrough discovery in determining exactly how the brain measures longer periods of time.
“Our study reveals how the brain makes sense of time as an event (that) is experienced. The network does not explicitly encode time. What we measure is rather a subjective time derived from the ongoing flow of experience,” says the Kavli Institute’s Dr. Albert Tsao, the study’s lead author. “The primary function of episodic time is to record the order of events within experience, which does not require a precise representation of metric time,” Dr. Tsao’s and his colleagues explain. A 2021 study in PubMed confirmed that the creation of episodic memories shapes our sense of time, and that the hippocampus “binds features of an event to its context.”
As we move through our day, our brains react to our environment in the form of thousands of tiny observations. The rumble of the coffee machine, the drop of milk that splashes from our cereal bowl onto the tablecloth and the crunch of cornflakes between our teeth are all observations that our brain makes about our environment without us consciously thinking about it. The observations our brains record occur in a continuous flow. This input from our environment then is encoded, or stored, in our memory. Certain events, particularly those that indicate changes in our environment, serve as boundaries between experiences. These boundaries help our brain organize encoded memories into segments, or episodes. For example, the sensory input above might be grouped into an episode labeled “breakfast.” Groupings of memories that were formed in the same environment are referred to as episodic memories.
“The primary function of episodic time is to record the order of events within experience, which does not require a precise representation of metric time.”
The accumulation of episodic memories form the neural clock at the crux of Dr. Tsao and his team’s discovery, and are responsible for helping humans gauge how much time has passed. The Journal of Neuropsychiatry study reached a similar conclusion: “There is evidence that events that occurred in different episodes are perceived as happening farther apart in time, and events occurring within an episode are perceived as happening closer in time.”
While no single area of the brain controls humans’ abstract concept of time, particular networks of neurons play a role in our brain’s perception of time by aiding in the formation of episodic memories.
Two years after my brain first became inflamed, I stood next to three of my colleagues on a stage holding my viola. After bowing to the audience, we sat facing each other, our musical instruments ready. After a quick cue from the first violinist, we launched into motion, the synchronized voices of our instruments blending precisely together.
Recovery from brain trauma is complicated and varies from patient to patient, Dr. Brown explained, adding, “Many variables could be involved, with the most important being how the damage occurred.” My own recovery had felt like scaling a mountain: exhausting and grueling, but worth it when I finally reached the summit and saw how far I’d come.
For much of the first year I spent recovering, I was too mentally and physically exhausted to practice more than a few minutes. I returned to playing the violin before the viola. Because the violin is much lighter than the viola, my atrophied arm muscles were able to hold it. When I was well enough to begin seriously practicing the viola, I worked extensively with a metronome, a device that musicians use to keep a steady beat.
Interestingly, the Journal of Neuropsychiatry study confirms that using a metronome can help brain trauma patients recover their sense of timing. “The therapeutic value of temporally based interventions (e.g., rhythmic cueing, slow rhythmic drumming) has been demonstrated for multiple neuropsychiatric conditions.”
Six years after my recovery, my memory overall is not as sharp as it was before my illness. I use to-do lists to keep myself on track. I triple-check the rehearsal dates on emails I send my students to make sure I haven’t listed the wrong day or month, although sometimes mistakes still slip through. I also sometimes struggle to remember how far back events in my past happened. I’ll catch myself wondering if I had the oil in my car changed three months ago or a year ago. But every time I take my viola out of its case, I feel grateful to be able to think like a musician again.
While performing in the viola section of an orchestra recently, my mind drifted briefly to the complex method through which the brain comprehends time. Sensory input becomes tiny memories, which then become encoded into episodes that the brain uses to estimate how much time has passed. Then my mind returned to the musicians on stage moving in time: many voices blending together to create a moment, a phrase, then an entire symphony.
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A brain injury removed my ability to perceive time. Here's what it's like in a world without time - Salon
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