Our perception of time is influenced by neurochemical states that control mood, stress, and happiness. Fasting, particularly intermittent fasting, has positive effects on gene expression and weight loss. Entrainment is the way our biology and psychology are linked to external factors, such as circannual rhythms controlled by neurons in our eyes, brain, and body. Seasonal oscillations in testosterone and estrogen are correlated with longer days and increased desire for romantic interactions and overall energy. Circadian timing is regulated by clock genes in every cell and can be entrained through exposure to bright sunlight in the morning and avoiding bright light in the evening. Timing physical activity and eating windows are crucial for entraining our internal perception of time. When circadian entrainment is disrupted, time perception suffers. Ultradian cycles of 90 minutes govern sleep and focus, with the first 90 minutes after waking up being the most optimal for focused work. Dopamine and serotonin influence time perception, with dopamine leading to time overestimation and serotonin causing time underestimation. Trauma can impact time perception and memory encoding. Deliberate cold exposure increases dopamine levels and alters time perception. Fun experiences are remembered as short moments, while boring experiences are remembered as long moments. Dopamine release resets the start of each time bin on our experience and governs our perception of time. Habits and dopamine release can be used to structure the day and improve time perception. The book "Your Brain Is a Time Machine" by Dr. Dean Buonomano explores the neuroscience and physics of time.
Introducing Time Perception, Note on Fasting & Supplements
Our perception of time is linked to neurochemical states that control mood, stress, and happiness. It shapes our evaluation of the past, our sense of the present, and our expectations for the future. We have the ability to control the speed at which we experience life. Tools and protocols can enhance our ability to dilate and contract time. Fasting, particularly intermittent fasting, has positive effects on gene expression and aids in weight loss. Whether or not supplements break a fast depends on their impact on resting blood glucose levels. Fish oil and supplements without sugar or much carbohydrate are unlikely to raise blood glucose levels and can be considered fasting-friendly.
Entrainment, Circannual Entrainment, Melatonin
Entrainment is the way in which our biology and psychology are linked to external factors. It involves circannual rhythms controlled by neurons in our eyes, brain, and body, marking the passage of time throughout the year. Light inhibits the release of melatonin, a hormone that regulates sleep and other hormones. The amount of melatonin released is influenced by the length of daylight, with more light leading to less melatonin and vice versa. Our brain and body have a precise mechanism to average the amount of light we receive and adjust melatonin levels accordingly. Melatonin plays a crucial role in entraining our internal state, mood, energy levels, and even appetite to external events such as the rotation of the Earth around the sun. This entrainment process affects every cell and system in our body.
Seasonal Oscillations in Testosterone & Estrogen, Tool 1
Seasonal oscillations in testosterone and estrogen:
- The amount of testosterone and estrogen produced by humans varies throughout the year.
- Longer days are correlated with increased production of testosterone and estrogen.
- Increased hormone levels are associated with increased desire for romantic interactions, aggression (not violent), overall energy, and mood.
- Sunlight exposure to the skin, even with clothing on, results in significant increases in testosterone and estrogen.
- This effect can occur even with cloud cover and is not inhibited by sunscreen.
- Our hormones are influenced by the external light-dark cycle, but exposure to bright lights can override this natural entrainment.
- Oscillatory events related to day length affect our hormones, such as melatonin, testosterone, and estrogen.
- Hormone levels impact our mood, outlook, and behavior.
Circadian Timing, Tools 1, 2, 3 (for Circadian Entrainment)
The circadian time cycle is a 24-hour rhythm controlled by a clock in the roof of our mouth, determining periods of activity and sleep. Circadian entrainment occurs through gene oscillation in every cell, with key genes being PER, BMAL, and CLOCK.
Key points:
- Circadian timing is regulated by clock genes in every cell, synchronized with the light-dark cycle.
- Precise entrainment is important for overall health, achieved through exposure to bright sunlight in the morning and artificial lights throughout the day.
- Avoiding bright light exposure in the evening is crucial for maintaining a healthy circadian clock.
- Disruptions to the circadian clock can negatively impact time perception.
- There are alternative methods to entrain the circadian clock.
Tool 4: Timing Physical Activity; Tool 5: Timing Eating Window
Timing physical activity and eating window are crucial for entraining our internal perception of time to the external events of the world. Here are the key points:
- Exercising at a consistent time of day, preferably within plus or minus two hours, positively affects circadian entrainment.
- Eating within the same time window each day, rather than at exact meal times, is crucial for maintaining circadian entrainment.
- Disruptions to the circadian clock can impact time perception.
When Circadian Entrainment is Disrupted, Time Perception Suffers
When circadian entrainment is disrupted, time perception suffers.
- People in isolated environments without clocks or exposure to sunlight underestimate how long they have been there.
- Perception of shorter time intervals, such as minutes or seconds, is also disrupted.
- Accurate time perception is crucial for optimal performance.
- Well-entrained circadian rhythm is important for maintaining precise time perception.
Tool 6: Ultradian (90min) Cycles & Focus
Ultradian (90min) Cycles & Focus:
- Ultradian entrainment refers to the 90-minute cycles that govern various aspects of our daily lives, including sleep and focus.
- These cycles determine the distribution of slow-wave sleep and REM sleep during sleep.
- Our ability to engage in focused and alert mental or physical work is highest during the first 90 minutes after waking up.
- Utilizing 90-minute work cycles can be beneficial for maintaining focus and accomplishing tasks.
- Achieving and sustaining focus within these cycles can be challenging.
- Ultradian cycles are controlled by the release of neurochemicals such as acetylcholine and dopamine.
- After approximately 90 minutes, the levels of these chemicals decrease, leading to a decrease in focus and productivity.
- Unlike circadian rhythms, ultradian rhythms can be initiated at any time, allowing individuals to optimize their work and performance.
- It is important to set these cycles for focused work, minimizing distractions and putting away phones and the internet.
- Limiting these cycles to no more than three, ideally two or one, is suggested as they can be mentally taxing.
- The cycles should be spaced by at least two to four hours and involve focused, hard work on challenging tasks.
- Ultradian cycles play a role in our focus and productivity, regulated by dopamine and serotonin levels in the brain.
- Most people can only handle one cycle per day without feeling mentally drained.
- Time perception is influenced by these cycles, but it has not been discussed in detail.
Our Sense of the Passage of Time: Present, Prospective, Retrospective
Our sense of the passage of time can be categorized into three forms: perception of the present, prospective timing, and retrospective timing. These forms rely on simple molecules in the human nervous system. Molecules such as dopamine, norepinephrine, and serotonin, known as neuromodulators, can affect our perception of time by modulating neural circuits. Literature suggests that dopamine and serotonin can modulate our perception of time in both animals and humans.
Dopamine (& Nor/epinephrine) Lead to Time Overestimation; Frame Rate
Dopamine and norepinephrine, neurotransmitters in the brain, lead to time overestimation by increasing the frame rate. This fine-slicing of time bins makes time appear to move slower, resulting in the overestimation of time. Serotonin, on the other hand, causes people to underestimate time.
Serotonin & Time Underestimation; Decreased Frame Rate
Serotonin and related molecules in the brain can cause individuals to underestimate time due to slower frame rates. This effect is observed with elevated serotonin levels or cannabis use. Pharmacology can manipulate time perception by adjusting serotonin levels. Changes in dopamine, norepinephrine, and serotonin throughout the circadian cycle also influence time perception.
- Serotonin and related molecules in the brain lead to slower frame rates and time underestimation
- Elevated serotonin levels and cannabis use can cause this effect
- Pharmacology can manipulate time perception by adjusting serotonin levels
- Changes in dopamine, norepinephrine, and serotonin throughout the circadian cycle influence time perception
Dopamine vs. Serotonin Across the Day; Tool 7: When to Do Rigid vs. Creative Work
Dopamine and norepinephrine are more elevated than serotonin in the brain and body, especially in the first half of the day. Serotonin levels increase in the second half of the day. This affects our perception of time, with people tending to overestimate time in the morning and underestimate it in the evening. It is suggested that structuring the day with the most difficult tasks in the morning is beneficial because our cognitive abilities, influenced by dopamine and norepinephrine, are better suited for problem-solving during that time.
Key points:
- Dopamine and norepinephrine are more active in the first half of the day, while serotonin levels increase in the second half.
- Our perception of time is influenced by these neurotransmitters, leading to overestimation in the morning and underestimation in the evening.
- Structuring the day with challenging tasks in the morning takes advantage of our cognitive abilities influenced by dopamine and norepinephrine.
- Different tasks require different neurotransmitter states, with dopamine being better for certain tasks and serotonin being better for others.
- Understanding the specific requirements of a task in terms of time perception is important for determining when to do rigid vs. creative work.
Example of Tool 7
The most profound aspect of the text is how neurotransmitters like dopamine and serotonin influence time perception.
- Tasks requiring precision and adherence to rigid rules are best done in the early part of the day when dopamine and norepinephrine levels are higher.
- Dopamine and norepinephrine enhance time perception and make the brain more efficient.
- In the afternoon when serotonin levels are higher, the brain is better suited for creative and flexible tasks.
- Serotonin levels make the brain more suitable for tasks that do not have strict right or wrong answers.
How Sleep Deprivation Degrades Performance
- Sleep deprivation disrupts the regulation of dopaminergic, noradrenergic, and serotonergic states throughout the day
- Lack of concentration and disrupted sense of time are common effects of sleep deprivation
- Maintaining a limited dopaminergic noradrenergic state in the early part of the day and pushing the serotonergic state towards the second half of the day is crucial
Trauma, “Over-clocking” & Memories; Adjusting Rates of Experience
Trauma, "over-clocking," and memories are discussed in relation to the adjustment of rates of experience. The key points are:
- Trauma can impact our perception of time, leading to "over-clocking."
- Over-clocking occurs when dopamine and norepinephrine increase during a traumatic event, causing heightened alertness and a slowed perception of time.
- The memory system records the precise firing of neurons during an event, including the sequence and rate of firing.
- Traumatic events are deeply imprinted in our memory, not only in terms of the specific neurons firing but also the timing and rhythm of their firing.
- Memories are encoded by the specific neurons that fire and the rate at which they fire.
- "Over-clocking" refers to a situation where the frame rate of memory is so high that it becomes difficult to shake off associated emotions.
- Various treatments for trauma, such as EMDR, ketamine therapies, and exposure therapies, aim to reduce the emotional weight of the memory and allow individuals to control the rate of the experience in their memory.
- The ultimate goal is to divorce the emotional activation from the memory itself.
- By adjusting the rate of memory playback, individuals can potentially reduce the emotional weight associated with trauma memories.
- Overclocking, a state of heightened dopamine and neurogenic activity, can lead to indelible marks of traumatic events in the brain.
- Trauma treatment aims to uncouple the emotional impact of these events.
Why Trauma Involves Dopamine & Epinephrine, Arousal
- Dopamine and norepinephrine are released during states of arousal, positive or negative.
- These neurotransmitters are associated with changes in time perception and are commonly involved in traumatic events.
- Dopamine is not only related to reward, but also to motivation, pursuit, and drive.
Dopamine, Spontaneous Blinking & Time Perception; Tool 8
Dopamine, Spontaneous Blinking & Time Perception:
- Dopamine is associated with heightened states of arousal and can lead to a fine-slicing of time.
- Spontaneous blinking, influenced by dopamine, can shift our perception of time and lead to overestimations.
- Blink rate is related to frame rate, with less blinking slowing down perception and more blinking speeding it up.
- Neuromodulators like dopamine and serotonin control this parameter of visual attention and time perception.
- Time perception involves various brain areas and is not controlled by a single area.
Deliberate Cold Exposure, Dopamine, Tool 9: Adjusting Frame Rate in Discomfort
Deliberate cold exposure has various positive effects on the body, including increased metabolism, brown fat stores, reduced inflammation, and increased resilience. It also robustly increases baseline levels of dopamine, which can alter one's perception of time. By adjusting thinking or using distraction techniques, individuals can better endure the discomfort of cold exposure, as the increased dopamine levels cause the perception of discomfort to be fine-sliced or experienced in slow motion.
Fun “Feels Fast” BUT Is Remembered as Slow; Boring Stuff “Feels Slow,” Recall As Fast
The perception of time is influenced by the level of excitement or boredom experienced during an event. Fun and varied experiences, associated with high dopamine levels, are remembered as short moments, while boring and empty experiences, associated with low dopamine levels, are remembered as long moments. This phenomenon is influenced by the release of dopamine and serotonin in the brain, as well as the influence of hormones.
Retrospective Time, Context Variation & Enhanced Bonding with Places & People
The relationship between time perception, memory, and our connection to places and people is explored in this video. Key points include:
- Novel experiences in a particular place can make us feel like we have been there longer.
- Multiple novel experiences with someone in different contexts can make us feel like we know them better and have spent more time with them.
- This phenomenon is influenced by neuromodulators and novelty.
- It shapes how we perceive events and relate to places and people.
Dopamine Release Resets the Start of Each Time Bin on Our Experience
Dopamine release resets the start of each time bin on our experience.
- Dopamine is released in response to both desired outcomes and unexpected events.
- Dopamine serves as a flexible currency in the brain, not just for positive events, but also for unexpected ones.
- Dopamine release affects our perception of time and how we divide our experiences into time intervals.
- The timing and frequency of dopamine release set the pace for our entire perception of events.
- Dopamine release signals the end of one phase of our experience and the beginning of a new phase.
- Dopamine release governs our perception of time and influences how we structure our day and allocate our time.
Habits & Time Perception; Tool 10 (Setting Functional Units of Each Day)
Setting specific habitual routines throughout the day can have a significant impact on our perception of time. By engaging in habits that release dopamine, we can divide our day into functional units. This not only makes us feel motivated and good, but it also becomes the way we structure and experience our day. Engaging in specific habits that we can perform well helps set the frame rate of our day, according to a study on basketball viewing. Dopamine plays a role in marking time and habits can invoke dopamine release, serving as markers for the passage of the day. By utilizing habits, individuals can segment their day into distinct functional units. This can be beneficial for structuring one's life and improving time perception. The Huberman Lab Podcast offers a newsletter with further information and examples on using habits and dopamine to structure the day for optimal performance.
Synthesis & Book Suggestion (Your Brain Is a Time Machine by D. Buonomano)
The most profound aspect of the text is the exploration of the relationship between neuroscience and physics in understanding time.
Key points:
- The book "Your Brain Is a Time Machine" by Dr. Dean Buonomano delves into the neuroscience and physics of time.
- It discusses time perception and how our brain constructs our experience of time.
- The book offers insights into the nature of time and its impact on our lives.
- The speaker expresses interest in inviting Dr. Buonomano as a guest on the podcast in the future.