Summary of Russell Foster's Life Time

By IRB Media

Please note: This is a companion version & not the original book. Book Preview:

#1 Our bodies are rhythmically driven by endogenous changes in our nervous systems. The Earth’s rotational axis generates the seasons, and the Moon's gravitational pull stabilizes it.

#2 The human body is organized around a 24-hour cycle of activity and rest. The brain contains around 86 billion neurones, and 50,000 work together as a master biological clock to coordinate our circadian rhythms.

#3 The ‘master clock’ in humans and all mammals is located in the brain called the ‘suprachiasmatic nuclei’, or SCN. The discovery of this structure was a shock to researchers in the 1920s, who had noted that rats under constant conditions of darkness run in a running wheel with rest/activity rhythms that are a little shorter than 24 hours.

#4 The SCN is the location in the brain where the circadian rhythm is generated. It contains about 50,000 neurones, and each has its own clock. The electrical activity of individual SCN cells is robust and independent, and keeps ticking away at a slightly different time from each other.

• Language: English
• Publisher: IRB Media
• Release date: Sep 12, 2022
• ISBN: 9798350001754

IRB Media

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Insights on Russell Foster's Life Time

Contents

Insights from Chapter 1

Insights from Chapter 2

Insights from Chapter 3

Insights from Chapter 4

Insights from Chapter 5

Insights from Chapter 6

Insights from Chapter 7

Insights from Chapter 8

Insights from Chapter 9

Insights from Chapter 10

Insights from Chapter 11

Insights from Chapter 12

Insights from Chapter 13

Insights from Chapter 14

Insights from Chapter 1

#1

Our bodies are constantly in motion, driven by rhythmic, endogenous changes. The Earth's tilt on its rotational axis generates the seasons, and the Moon's orbit around the Earth produces the tides.

#2

The human body is organized around a 24-hour cycle of activity and rest. The activity of organs such as the stomach, liver, small intestine, and pancreas, and the blood supply to these organs, needs to be appropriately adjusted across the day and night.

#3

The human master clock is located in the brain called the suprachiasmatic nuclei, or SCN. The discovery of this structure was a shock to scientists in the 1920s, who noted that rats under constant conditions of darkness run in a running wheel with rest/activity rhythms that are a little shorter than 24 hours.

#4

The SCN, which is located in the brain, contains about 50,000 neurones. Each has its own clock. The electrical activity of individual SCN cells is monitored and shows robust and independent circadian rhythms.

#5

The clock ticked in 2017, after almost 40 years of research, when three researchers from the USA, Jeffrey C. Hall, Michael Rosbash, and Michael W. Young, shared the Nobel Prize for discovering how it worked.

#6

The human brain accounts for about 2 percent of the body’s weight, but uses 20 percent of its total energy intake. The brain is 73 percent water, but it takes only 2 percent dehydration for brain function to be severely impaired.

#7

The molecular clockwork that generates the 24-hour rhythm in the cell is a negative-feedback loop that consists of the following steps: clock genes located in the nucleus of the cell create a message that provides the template to build clock proteins. These proteins are made in the cytoplasm. The clock proteins then interact to form a protein complex which moves into the nucleus to inhibit or switch off the production of further clock proteins.

#8

There are clocks within the cells of the liver, muscles, pancreas, adipose tissue, and probably in every organ and tissue of the body. These cellular peripheral clocks seem to use the same negative-feedback molecular clockwork as the SCN clock cells.

#9

The circadian system, which regulates our bodies’ rhythms, fine-tunes our bodies to the demands of the 24-hour day. It is this internal and external alignment that I want to explore in chapter 3.

#10

The clock gene is like the cogwheels of a mechanical clock. It interacts with other genes to generate a 24-hour rhythm, and if you take one of these ‘cogs’ away, or damage a cog, the clock will be significantly altered or even stopped.

#11

We do have annual rhythms, which are peaks in birth, hormone release, suicide, cancer, and death. For example, in the northern hemisphere, and perhaps counterintuitively, suicide in spring is significantly higher than in the winter around December.

#12

The master clock is located in the brain, and it is the SCN that coordinates the circadian rhythms of the peripheral clocks. But in birds, reptiles, amphibians, and fish, there are several organs that can act as a master clock.

Insights from Chapter 2

#1

Sleep has always been disliked by society. It was seen as a form of sickness in need of a cure. Today, sleep is still regarded