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Written by Nick Joseph

May 2019

Positive Thinking

Are the left and right brain hemispheres calibrated differently towards optimism?


“They’re on our left.  They’re on our right. They’re in front of us, they’re behind us.  They can’t get away this time.” - Chesty Puller, USMC




It’s the fuel behind every business startup, cavalry charge, and “can I have your phone number” in human history.  It’s what makes people train for marathons, prepare for long battles with cancer, and what allows Ole Miss fans to muscle through college football season after being mathematically eliminated from legitimate bowl contention by Week 3.


Vegas was built on it.


But optimism has also been the cause for many a shattered physical and emotional dream, as so clearly laid out in the DJ Jazzy Jeff and Fresh Prince classic, “I Think I Can Beat Mike Tyson.”  


If optimism is so shaky and unreliable, why do studies continue to suggest people favor it over accuracy when making long-range predictions about events in their lives? (1, 2).  Wouldn’t a smarter animal temper its excitement over winning the lottery with a good healthy dose of actual statistics? Statistics aside, wouldn’t it at least know that winning the lottery is either a one-way ticket to bankruptcy or having that slimy dude with hand tats shove a craftsman down their throat on next week’s episode of ‘My Lottery Dream Home?’


It’s no small wonder that the species who planned the Manhattan Project and lunar landing is composed of the very same individuals who put the fuel tank at the back of the Ford Pinto and green-lit ‘Battlefield Earth.’


Say what you will about human beings, but we got range, and that range begins with the gray loaf of neural bread in our head, the brain.  Each of the brains two hemispheres can process things independently, but the way we actually experience life is controlled by a third thing.  While that can (and has) led to tremendous tomes on the subjectivity of ‘reality,’ science thrives in cold, third-party objectivity. Therefore, several experiments have been conducted to find out what each side of the brain is thinking, and which one seems to direct our behavior in a given circumstance.


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The Eyes Have It

Researchers wanted to see if they could figure out which hemisphere of the brain was most activated during a simple reading test.  They took 26 college students — 13 of whom were diagnosed with depression — and had them look through a viewing box separated by a partition.  In front of them were two words, one positive (“vibrant,” e.g.), one negative (“failure”). When the positive word appeared on the right side (meaning, it was processed by the brain’s left hemisphere), the participants’ attention shifted to the positive word. When they switched the positive word to the left side, the students took in both words, but invariably focused more on the positive word than on the negative. This is a good indication that the left hemisphere favors positive stimuli more than the right hemisphere. (4)

So what good is the right hemisphere if we seem to invest our unconscious capital in seeing only sunshine and unicorns? In another study involving people with high anxiety looking at pictures of happy and fearful faces, they paid significantly more attention to the fearful faces than the happy ones when the fearful faces were on the left side of the screen. When the faces switched sides, this didn’t happen: a pretty good sign that the right hemisphere (which processed the images to the person’s left) is more concerned with threats and negative outcomes. (5)  Similar results have been documented in another test involving auditory stimuli: people receiving warnings about sun exposure in their left ear (right hemisphere) were more likely to use sunscreen than people who heard the same warnings in their right ear (left hemisphere). (6)

Brain Hemispheres

Resistance is Futile - Or Is It?


It seems, though, that the information gained from experience can get relayed back to the hemispheres, implying we have some control over these seemingly autonomic processes.

While trying to understand fear-related behavior in dogs, Martin Seligman and his team stumbled upon a discovery that helped explain depression in humans. Essentially, two groups of dogs were put in separate rooms where his team would ring a bell, wait a moment, and then give the dogs a minor electrical shock.  


In one room there was only one possible outcome: five seconds after the bell rang, the shock came.  But the second room had a button in it, and the dogs in that room learned that if they pushed the button after hearing the bell, they would not get shocked.  

Learned Helplessness

But here’s where it gets interesting: they took those same two groups of dogs and put them in a new room with a small partition in the middle.  The floor on one side of that partition would shock the dog, but the floor on the other side was safe. They rang the same bell and maybe you can guess the outcome. The dogs from the bell/shock room simply prepared for their fate. Meanwhile, the dogs from the room with the button searched for an escape route, and figured out that if they jumped over the partition — how’s that for a metaphor — they could avoid the pain of the pending shock. (7)

What this showed was that helplessness can be learned.  And it’s not just dogs, but people, too.  From the abused child to the henpecked husband, people can learn to surrender their futures to outside forces, believing their only option preparation for the inevitable.  That’s devastating news to hear, sure, but this experiment also suggests that people can choose to empower themselves, given the option to do so.  Those dogs in the second group internalized their situation - feeling they were in control of their own outcomes.  


Analytical Psychologist Carl Jung argued we have a Conscious Mind that puts a mask on our face to protect us from the dirty little secrets our Unconscious Mind actually knows about us.


It seems like our physical minds manifest this dichotomy as well.  Without the optimism of our Left Hemisphere, nothing would ever get done.  We would lack all incentive; it’s the glory of the ideal outcome that propels all human decisions.  Why else would anyone go camping in the wilderness away from all modern conveniences other than to experience the mountains, waterfalls, and idyllic beauty of nature?


But the Right Hemisphere may be more concerned for our well-being, warning us to prepare for the un-ideal outcomes we will face: “Going camping?  Take some bug spray. Maybe bear spray, too. You know what? Just take a shotgun. Actually, don’t go camping. Things in nature are there to eat you.”


There seems to be an inherent understanding within us that life will be challenging, and we are equipped from birth with the tool that anticipates meeting them.  It may be that not only can we decide to take on those challenges through optimism via our left hemisphere, but we stand a good chance to prepare for and overcome them thanks to the activity of our right hemisphere.  


To paraphrase Socrates, “That’s pretty cool, man.”



  1. Prescribed Optimism: Is It Right to Be Wrong About the Future? By David A. Armor, Cade Massey & Aaron M. Sackett (2008, Psychological Science).

  2. Replication of Prescribed Optimism: Is It Right to Be Wrong About the Future? Anna van ’t Veer, Bethany Lassetter, Mark J. Brandt & Pranjal M Mehta.  (The Open Science Collaboration)

  3. Hecht D. The neural basis of optimism and pessimism.  Exp Neurobiol.  2013;22(3): 173-179.  doi: 10.5607/en.2013.22.3.173.

  4. Kakolewski KE, Crowson JJ, Jr, Sewell KW, Cromwell RL. Laterality, word valence, and visual attention: a comparison of depressed and non-depressed individuals. Int J Psychophysiol. 1999;34:283–292.

  5. Fox E. Processing emotional facial expressions: the role of anxiety and awareness. Cogn Affect Behav Neurosci. 2002;2:52–63.

  6. McCormick M, Seta JJ. Lateralized goal framing: how selective presentation impacts message effectiveness. J Health Psychol. 2012;17:1099–1109.


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