Is Technology Changing Our Circadian Rhythm?

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Written by Consensus
8 min read

Is technology changing our circadian rhythm?

Check out this answer from Consensus:

Technology has undeniably changed our circadian rhythms by altering our exposure to natural light cycles. The consequences of this disruption are far-reaching, affecting sleep, cognitive performance, and mental health. Addressing these issues requires a multifaceted approach, including behavioral and lifestyle changes, as well as the development of technological interventions to realign our circadian systems. As research in this field progresses, it will be essential to balance the benefits of modern technology with the need to maintain healthy circadian rhythms.

Circadian rhythms are intrinsic, approximately 24-hour cycles that regulate various physiological and behavioral processes in humans and other living organisms. These rhythms are synchronized with the solar day through environmental cues, primarily light. However, the advent of modern technology, particularly artificial lighting and pervasive digital devices, has significantly altered our interaction with natural light cycles. This article explores how technology is impacting our circadian rhythms and the potential consequences of this disruption.

The Role of Circadian Rhythms

Circadian rhythms are essential for optimizing behavior and physiology. They regulate sleep-wake cycles, hormone release, eating habits, and other bodily functions. The master clock in the brain’s hypothalamus coordinates these rhythms by responding to light signals, ensuring that our internal clocks are aligned with the external environment .

Impact of Artificial Lighting

The introduction of artificial lighting has profoundly affected our circadian rhythms. Exposure to artificial light, especially during nighttime, can disorganize the circadian system. This disruption occurs at multiple levels, from molecular clocks that regulate cellular activities to the synchronization of daily behavior cycles with the solar day. The widespread use of artificial lighting has led to increased circadian misalignment, contributing to sleep disorders and other health issues.

Technology and Cognitive Performance

Recent advancements in technology, such as smartphones and wearable devices, have provided new ways to study and monitor circadian rhythms. These technologies offer less intrusive methods to infer circadian rhythmicity in everyday settings. For instance, mobile toolkits and wearable systems can unobtrusively detect changes in alertness and cognitive performance, helping to develop interventions that support mental and physical health.

Mental Health Implications

There is a bidirectional relationship between circadian rhythms and mental health. Disrupted circadian rhythms are often associated with mood disorders, such as depression and anxiety. Conversely, mood disorders can exacerbate circadian misalignment. Factors like jet lag, night-shift work, and exposure to artificial light at night can precipitate or worsen affective symptoms in susceptible individuals. Understanding these interactions is crucial for developing strategies to mitigate the negative impact of circadian disruption on mental health.



Is technology changing our circadian rhythm?

John Axelsson has answered Near Certain

An expert from Karolinska Institutet in Sleep Research, Cognitive Science, Psychology, Immunology

The purpose of the circadian system is to regulate a number of processes so they are in concordance with the changes of day and night. The master clock (SCN in hypothalamus) has a near 24 hour intrinsic rhythm and is very sensitive to light around dusk and dawn, so to fine tune the circadian system; which allows the system to be dynamic and adapt to the seasonal changes in duration of day and night. Since light is the primary entrainer or ‘zeitgeber’ of the system, modern technology has a huge impact on our circadian rhythm. Exposure to electric light at times other than during daytime has the potential to strongly affect the rhythm – fooling the rhythm that it is daytime. Recent studies have shown that as little as 25-30 lux in the evening blocks 50% of melatonin in the average person, and people who are more sensitive to light in the evening are more likely to have a late circadian rhythm. Taking people camping, away from their light polluted modern lives, has drastic effects on their circadian rhythm. The average person advances their rhythm with more than an hour, and evening people will advance more than morning people. In all, light emitting technology (such as light bulbs, TV-screens, computer screens, mobile devices etc, can strongly affect our rhythms, at least when exposure is outside normal daytime.


Is technology changing our circadian rhythm?

John Caldwell has answered Near Certain

An expert from Coastal Performance Consulting in Psychology, Sleep Research, Pharmacology, Data Science

Consider the lighting and other technology that has enabled shift work as well as the transportation technology that has enabled rapid transit across several time zones. The body’s internal clock (circadian rhythm) evolved to function on a 24 hour cycle because of the day/night, dark/light timing that is associated with the Earths rotation on its axis, and this clock is disrupted by behavior changes that deviate from this schedule (primarily changes in the sleep/wake schedule). If you think about what life was like before we had electric lights and modern aircraft (and even trains), it’s easy to see that prior to these technological innovations, a person would probably have lived their entire lives in the same “time zone” since their mobility was limited to walking or riding horses, and they also would likely have worked during daylight and slept at night their entire lives simply as a matter of practicality since it would have been difficult to perform most tasks at night without artificial lighting. But in today’s modern world, both shift work and jet travel are common, both routinely require drastic sleep/wake schedule changes in short periods of time, and both create major challenges for an internal physiological clock that for most of history was on a relatively stable schedule. The bottom line is that technology has changed quite a bit in recent history whereas human physiology has remained pretty much the same as it always has been. Perhaps after another million years or so, humanity will evolve to better cope with modern circadian challenges, but until then, we will struggle to adapt to anything that changes our routine day-to-day schedules.


Is technology changing our circadian rhythm?

Jamie Zeitzer has answered Near Certain

An expert from Stanford University in Sleep Research

Well, it depends on what you mean by ‘changing’. Our circadian clock is innate and modulated by millions of years of evolution. Technology is not changing the structure of the clock or how it operates, but does impact the clock in ways unlikely selected for by evolution. There are two main ways in which technology can impact the clock, directly through artificial light exposure, and indirectly through changing behavior that then leads to unusual patterns of light exposure. Light is mainly doing two things to the clock. It is setting the time of the clock and it is changing the amplitude or strength of the clock. Under a solar light-dark cycle without any artificial light, our clocks would be set to an earlier hour. With artificial light, our clocks are often set to a later hour. In and of itself, this is not a pathological event. For example, if your clock was set under a solar cycle such that sleep was predicted to occur from 8pm until 4am, but under an artificial light cycle to occur from midnight until 8am, that would be fine (from a health perspective). Under a solar cycle, once the sun goes down, you are relegated to stars, moonlight, and firelight (at best). With technology, once the sun goes down, you have artificial light as well as the behaviors that this enables. These behaviors, unfortunately, often engender erratic timing of sleep (and therefore light exposure). This will weaken (albeit, temporarily if you go back to having a regular light cycle) the amplitude of the circadian clock and lead to downstream negative health effects. It is often, though not necessarily, associated with curtailed amounts of sleep, which independently has negative health effects. So, is technology changing our circadian rhythm? From an evolutionary perspective, probably not so much. From a behavioral perspective, most definitely.


Is technology changing our circadian rhythm?

Cele Richardson has answered Likely

An expert from University of Western Australia in Sleep Research

There are many mechanisms that may explain the possible relationship between technology use and sleep. It is often said that bright screen light delays the circadian rhythm. There is evidence that 1.5 hours (or more) of bright screen use reduces the natural night time increase in melatonin, and this effect may compound over multiple nights. However, this does not appear to translate to taking longer to fall asleep. Professor Michael Gradisar wrote a very informative blog on this topic, including some key references. Follow this link to read more:

Whilst there is a consistent (cross-sectional) association between technology use and sleep, there is less consistent evidence that technology use actually predicts changes in sleep over time. Methodological differences (e.g., how technology use and sleep are measured) between studies likely contribute to differences in findings. What is becoming clearer, is that a bi-directional relationship between technology use and sleep is likely. That is, technology use may affect sleep over time, yet individuals who have trouble sleeping may subsequently increase their technology use. Many people use technology as a sleep aid, and this is particularly relevant to individuals with a delayed (late) circadian rhythm. For these individuals, they may turn to technology as a way to “fill in” time before they feel physiologically ready to sleep. In this way, technology use may be more adaptive than laying in bed awake, feeling frustrated.

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