From ‘We are All Stardust. Scientists who shaped our world talk about their work, their lives, and what they still want to know’ - Conversations with Stefan Klein

Neuroscientist V.S.Ramachandran on consciousness

……at that time a man had appeared in my lab with a huge bejeweled cross and told me about his conversations with God. He said he had understood the true meaning of the cosmos.

A madman?

No, not in the least. Based on previous work by Norm Geschwind, we conjectured that a region in this man’s temporal lobes, a cerebral center behind the ears, was much more active than normal. That’s often true of epileptics. His religious experiences might have to do with this heightened activity.

…………

Those effects have actually been known for a long time. People who suffer from overactive temporal lobes – for example, during an epileptic seizure – report mystical experiences. Some neurologists have even attempted to explain famous experiences of religious revelation, such as those of Saint Paul and Saint Teresa, as cases of temporal epilepsy.

Molecular biologist Elizabeth Blackburn on aging

………ciliates…….single-celled organisms…….They can reproduce asexually by simply doubling themselves……..Ciliates are immortala…..can divide endlessly, perpetually beginning a new life.

………..telomerase. it helps form a sort of protective sheath on the chromosome – the telomere, to which ciliates owe their endless life.

As we age, more and more cells die off without replacement. As a result, our bodily functions deteriorate. But humans have telomerase too. ….scientists found that in families with members who don’t produce enough telomerase due to genetic disease, those members suffer unusually early from age-related afflictions. This proved that telomerase delays aging for us as well.

…….we’ve witnessed a tsunami of insights on the connection between aging, diseases and telomere length.

What determines how well our cells regenerate?

The circumstances of life play an important role – especially chronic stress. ……The greater the number of terrible experiences they had to cope with, the more their telomeres had shortened on average.

As if each blow of fate cut off some of the thread of life.

Stress early in life seems to leave particularly deep traces in the nucleus. These results make one thing quite clear: how critical it is to protect our children. There are people, however, who can get over even great hardship amazingly well.

Apparently, how long we live is also hereditary.

……….To live to 120 is clearly permitted by the current gene pool of our species.

…….The three big killers of the elderly, cancer, cardiovascular diseases and diabetes, clearly are influenced by the state of our telomeres.

……..Telomere length by itself predicts a particular life expectancy only in statistical terms……..It is the combination of many factors that matters.

…….I’ve tried to exercise thirty minutes a day. That’s the only magic bullet against physical decline that I accept. The evidence for it is compelling.

……..Not even an expert can tell the difference between the organs of a young turtle and those of a hundred-year-old turtle.

Apparently, those amphibians have extremely efficient repair mechanisms………..an animal can either reproduce mainly in its younger years, as we do, in which case a longer life offers no biological advantage, or it can produce offspring until it dies, as the turtle does, in which case each year is a gain. However, it costs the organism a lot of energy to constantly stave off decline.

Physician and social scientist Nicholas Christakis on human relationships

……Every culture is rooted in a social network in which people reinforce one another’s attitudes.

Biochemist Craig Venter on the human genome

I have two copies of very fast metabolizing genes, and so I can drink lots of coffee and it has no impact. People who have slow metabolism or even medium metabolism for caffeine have a greatly increased risk of heart arrhythmias or heart attack if they have multiple cups of coffee, so it helps explain all the confusing information in the scientific literature about caffeine’s being good or bad for you. It totally depends on your metabolism.

Neuropharmacologist Walter Ziegigansberger on pain

The truly bad pain is the agony that begins very gradually – the slight ache in the back that gets more and more intense and over the years comes to define a whole life.

Sensitivity to pain is hereditary. And there are even people who are, as a result of their genetic endowment, completely insensitive to pain. Gender also plays a role. Most women are more sensitive to pain than men. That has to do with the female nervous system. Red-haired women, however, have an advantage. They have a genetic variant that makes them particularly responsive to certain opioids.

Whether the painkiller comes from outside or inside ultimately doesn’t matter. With techniques like meditation and yoga, you can induce the brain to use its own substances.

What actually causes the perception of pain?

Almost everywhere on your body, there are sensors known as nociceptors, which respond to heat, intense pressure, or chemical stimuli. When you’re injured somewhere, the nociceptors send a signal to the spinal cord, where something important happens: The pain signal takes precedence over all other messages from your body. In addition, the information is divided. One channel leads into areas of the cerebrum that localize the injury. Other impulses enter the deeper brain regions and trigger the unpleasant sensations.

You once asserted that dangerous pain isn’t intense, but faint.

The body is prepared for an acute injury. Opioids are released; in the worst case scenario, you pass out. But a nagging, recurring back pain, say, always slight, slight …..it can drive people to despair. All day long you’re focusing on whether its coming back. Gradually you get anxious. And then something fatal happens, You become more and more sensitive to the pain, because your nervous system is beginning to change. When the neurons are stimulated again and again, they amplify the incoming signals more and more. That’s how the brain learns – through repetition. In this case, it unfortunately learns pain. In that way, the initially slight sensation becomes stronger and stronger. In the end, the pain defines your whole life.

…….to doctors who cause anxiety. Because they don’t know for sure, they make diagnoses like: “Well, your back, its not the strongest. Even if you don’t have any serious problems now, you probably will in twenty years.” Out of fear, patients begin to pay attention to every little ache in their back. In that way, they program themselves for pain. And because they believe they have to go easy on their bodies, their muscles weaken and tense up all the more at the next opportunity.

There’s even a name for that process: iatrogenic, which refers to an adverse condition caused by a doctor.

……….We doctors should at least watch what we say – especially when we’re actually looking at healthy people. Language is the sharpest of all swords.

Anthropologist Sarah Hrdy on motherhood

Because women by nature have a slightly lower threshold for responding to a baby’s cries than men do. Even if both parents have the best intentions, she will get there before him to comfort the baby. Thus the baby becomes more attached to the mother than the father. In that way, a slight genetic difference between the sexes in the threshold of responding to infant cries develops into a great asymmetry.