The Man Who Drew Neurons

Ramon y Cajal’s "Advice for a Young Investigator"

Posted Oct 20, 2018

Cajal/Wikimedia commons
Source: Cajal/Wikimedia commons

You have probably seen the artful drawings of neurons done a century ago by Ramon y Cajal. I saw the originals exhibited at the University of California-Berkeley, and I learned that the sketches were done for real research rather than “art.” More important, they were done by the man who discovered the synapse. When I heard that Ramon y Cajal also wrote a book of career advice, I was eager to read it!

Cajal / Wikimedia Commons
Source: Cajal / Wikimedia Commons

Advice for a Young Investigator gives us a glimpse into the culture of academic research a century ago. It’s interesting because the author made such huge contributions to our knowledge of the brain. He discovered that neurons transmit electricity in only one direction. He wrote a textbook on the nervous system, based on his own extensive lab work and sketches, that was used to train doctors for generations. I wanted career advice from this person.

Anything written a century ago is of course rooted in old values and beliefs. If you look for political incorrectness, you will find it (for example, his advice on finding a wife who supports your research). But most of his advice is curiously similar to what you would hear today: work hard, persist through failure, and trust your own judgment.

So why does the same advice need to be repeated every generation?

Because it conflicts with our natural impulses.

Natural selection built a brain that makes careful decisions about where to invest its energy. It doesn't like to waste effort on failed endeavors. A lion would starve to death if it kept running after gazelles that got away. This makes it hard to persist when we run into setbacks.

The brain we've inherited seeks safety in numbers. A gazelle that wandered off would soon be eaten alive. Thus our brain alarms us with a bad feeling when we're isolated. This makes it hard to trust your judgment when the rest of the herd walks away.

Cajal/ Wikimedia Commons
Source: Cajal/ Wikimedia Commons

Our brain is designed to weigh risk and reward, but it defines them with neural pathways built from the risks and rewards of your past. New information has trouble getting in unless we invest our full attention. This leaves us with less energy for other things, so we often just stick to our old risk/ reward pathways.

Bad Advice

In the movies, science breakthroughs always seem to come from accidents or late-night beers.

In school, we are told that accomplishment come from privilege and genes.

These lenses do not motivate a person to invest the effort necessary to make a breakthrough. So why would anyone immerse themselves in their own research project the way Ramon y Cajal suggests?

Research stimulates our happy brain chemicals in new ways

Dopamine is released when you see yourself approach a reward. Our brain quickly habituates to old rewards, and it takes something new to stimulate it. Your passion project thrills you with dopamine...until you hit a snag. Visible progress toward rewards is needed to stimulates dopamine. We can't always make visible progress, but we can generate positive expectations internally. Of course your expectations may be wrong. You encounter huge obstacles sometimes, and your cortisol is triggered. As you struggle to rekindle positive expectations, Ramon y Cajal’s book can help.

Loretta Breuning
Source: Loretta Breuning

Oxytocin is released when a mammal finds social support. But following the herd restricts your options, so we all struggle to trade off the dopamine of greener pasture with the oxytocin of social support. Oxytocin is quickly metabolized so our brain is constantly looking for safety in numbers. When your passion project is critiqued or ignored, you may feel like a gazelle exposed to predators.  Re-reading Ramon y Cajal’s book can help you stimulate oxytocin because you feel him on the path with you.

Serotonin is released when a mammal feels confidence in its own strength. Your passion project is a great way to stimulate it. Serotonin makes it feel safe to assert and meet your needs. Alas, the nice feeling is hard to sustain because it's quickly  metabolized, and because the strength of others keeps getting your attention. This is why mammals are always eager for ways to stimulate serotonin. When your confidence droops, this book can help you feel your strength.

Ambition, Then and Now

The word "ambition" is often used as a pejorative in today’s world. We are taught to deny our self-interest and invoke "saving the world" as our only motivation. In this context, it can be jarring to hear Ramon y Cajal encourage ambition.

Getting real about ambition leads to a difficult thought loop. Your dopamine will droop because you don’t always make progress. Your oxytocin will sag when the herd shuns your big-hairy-audacious goal. Your serotonin dips when you face stronger rivals. Thus, in the short run, the illusion of "saving the word" can feel better than persevering in steps of your own choosing.

But action-steps toward goals are what make your inner mammal feel good. Real steps toward real goals stimulate happy chemicals. You deprive yourself of good feelings when you limit yourself to goals that come easily and keep you safely in the herd.

Ramon y Cajal does not advocate a reclusive life in the lab. On the contrary– he advocates having a family and a profession. He thinks your passion project benefits from continual contact with the world outside your lab.

It’s hard to do everything, of course. When I feel overwhelmed, I remind myself that my brain evolved for just such difficult trade-offs. A gazelle’s brain is constantly choosing its next step: one moment stepping toward greener pasture and the next moment stepping back toward the safety of the herd. If every ungulate can do this, I can do it too. I’m sure Ramon y Cajal would agree.

Your Career Brain vs. Your Mammal Brain

We do not consciously seek dopamine, oxytocin and serotonin when we make our career choices. The mammal brain cannot process language, so it does not report these motives in words. Your verbal brain finds lofty ways to explain the things you do for dopamine, oxytocin and serotonin.

These chemicals are not designed to flow all the time for no reason. They are only released when a mammal takes a step that meets a survival need. We are designed to live with ups and downs in our happy chemicals. Every career path has its ups and downs.

Every career has its predators, its fickle herds, and its unexpected obstacles. Bad feelings are inevitable on the road to a goal. It’s impossible to make progress every moment and enjoy a constant dopamine high. It’s impossible to have the support of others every moment and enjoy a constant oxytocin high. It’s impossible to see yourself in the position of strength every moment and enjoy a constant serotonin high. When you know the true source of your ups and downs, they are easier to manage. 

But life is complicated because our brain equates disappointment with survival threat. A lion's cortisol surges when it sees a gazelle get away. Cortisol alerts the lion to the threat of starvation if it doesn't find prey it can catch. Cortisol motivates the lion to give up on a failed catch and find a better prospect. When you fail at something, cortisol makes it feel like a survival threat. Just thinking about the possibility of failure can turn on that alarm signal. Cortisol motivates you to do whatever it takes to make it stop. Giving up on your goal may make it stop. And sometimes you need to give up on a failed chase. It's a difficult choice, but we have more neurons than a lion or a gazelle to weigh the risks and rewards with. Advice for a Young Investigator can help you integrate immediate feedback with long-run goals so your inner mammal can enjoy forward steps.

Learn more about your mammal brain from the Inner Mammal Institute's many free videos, articles and podcasts. And learn more about your dopamine, serotonin and oxytocin from my book, Habits of a Happy Brain: Retrain your brain to boost your serotonin, dopamine, oxytocin and endorphin levels