How do the mechanics of the cosmos dictate the seasonal cycles, days and nights, as well as our internal biorhythms?
A biorhythm is a sort of inner clock for the human body, which affects one’s physical and mental well-being. If you disrupt your biorhythm, such as when you travel to a country in a different time zone or by not going to bed until 2 am after a party, you will feel sleepy and tired the following day. It takes several days or even weeks before you get used to a different routine.
A circadian rhythm is a mechanism synchronised with the rotation of our planet, which lasts between 20 and 28 hours, and is one of the most important biorhythms. An example of a component of the circadian rhythm is the sleep / wakefulness cycle, but our temperature, the release of certain hormones and range of other phenomena are also parts of our circadian rhythm, as well as potentially other yet-undiscovered phenomena.
Using actigraphy to measure your activity during the day and night is by far the easiest method of observing your circadian biorhythm.
Taking your temperature via the mouth, vagina or rectum immediately after waking up and before any physical activity, is another way to measure circadian rhythm.
Also known as the sleep hormone, melatonin regulates people’s daily and seasonal biorhythms. Regularly extracting melatonin is another way to measure the circadian rhythm.
Our daily lives are technologically advanced but also very hectic. We often tend to have bad habits and make unhealthy lifestyle choices such as diet, the artificial prolongation of daytime, bad lighting, a lack of exercise and too much time spent in front of a computer. All of these increase the occurrence of various diseases, while long-term disruption of our cycles can lead to sleep disorders, nervousness and concentration problems. Abnormal daily rhythms have also been linked to obesity, diabetes, depression, bipolar disorder and seasonal affective disorder.
Our current research in this field now primarily focuses on psychiatry, in particular mood disorders and psychoses. However, we are also testing application in areas such as sleep medicine, neurology and lung medicine.
So how does this all work? A special population of nerve cells, located directly above the point where the optical nerves cross deep inside the brain, is what is known as the suprachiasmatic nucleus (SCN). Neurons themselves are cyclically active. However their activity is inaccurate and must be continuously synchronized, so the hands of our circadian clock are adjusted by daylight. Our retinas contain rods and cones and other light-sensitive cells. These are sensitive to blue light, which is particularly abundant in the morning and directly linked to the SCN, which is the mechanism that starts a new day. Another sprocket is the hormone melatonin, whose levels begin to rise in the evening. Melatonin tells us to go to bed and causes fatigue, and its levels start to decline in the second half of the night, which functions as a signal for us to wake up.
The cyclical processes in the SCN are genetically controlled, with some of the genes being overwritten during one part of the day. Their protein products cumulate and limit concentrations switch on a second gene, a gene which, thanks to its feedback response, inhibits the activity of the first gene. This is a simple mechanism, wouldn’t you say? But it works well, as do a range of similar genes. And because we are not genetically identical, also the circadian mechanisms in our brains are adjusted differently. That is why the population consists of individuals of various chronotype, from early birds to night owls.
This variety is completely normal. Nevertheless, we are variable from a different point of view as well, in a way we know very little about today. At the same time, the entire circadian machine, as any finely tuned mechanism, is extremely fragile. About twenty percent of people have noticeable problems in certain periods of the year when the amount of sunshine changes rapidly and their circadian systems, which are working at the limit of their capabilities, are not able to prevent the sudden destabilization of physiological phenomena. People with this predisposition may be susceptible to obesity, diabetes, season-based sleep deterioration, decreased performance and mood changes, among other things.
Serious circadian dysrhythmia and its accompanying volatile mood swings, is the tip of an iceberg. It can take the form of bipolar affective disorder (BAD) or recurrent depression. Many mood disorders seem to have something to do with disrupted circadian rhythms. This provides great hope for new forms of treatment: if we can make long-term records of changes in circadian stability, we can predict the onset of a new phase, or a relapse if you like, in predisposed individuals suffering from affective disorder. Being able to the indicate deterioration of a patient’s condition weeks before they notice any symptomatic changes in mood, quality of sleep or performance would be a huge victory. However, this requires long-term monitoring of circadian system parameters. Actigraphy, which monitors physical activity, is a great option, since how much we move determines our daily routines. Getting up, travelling to work, walking in the afternoon, falling asleep, sleeping marked with small periods of wakefulness and so on- this is our routine time and time again, essentially regular with variations enforced by external conditions.
Our current research in the field now primarily focuses on its uses in psychiatry, in particular mood disorders and psychoses. However, we are also testing application in areas such as sleep medicine, neurology and lung medicine, where circadian rhythms have been hypothesised to play a role.
It all starts with a simple wristband with activity sensor, permanently worn on the user’s wrist. The Mindpax wristband looks like a typical fitness band and measures a person’s physical activity and sleep. The user installs the free application on their mobile phone and the wristband’s data is transferred to it via Bluetooth. This allows the user to regularly check both their sleep and activity. All data collected by the mobile app is encrypted and sent to a server where it is evaluated. The user then chooses with whom they want to share their data via a web portal.
The main difference is in the way data is handled. Fitness bands / applications aggregate raw activity data into well-known fitness parameters such as the number of steps, calories burnt or periods of sleep, and the rest of the data is thrown away. The data analysis by Mindpax goes far deeper than that. We work with primary data, looking for long-term trends and links to an individual’s medical condition and its development as well as fitness parameters. As the amount of data grows, Mindpax’s algorithms are custom-adjusted for each user to detect deviations from the norm.