Written by: Matthew Sabatine
Disclaimer: The views expressed herein represent only the author of this article and not everyone at Common Issues.
Our unconscious minds can catalogue sensory inputs much more than our conscious minds. Have you ever experienced a feeling or thought that came out of nowhere? Nowhere wasn’t truly the source. The thought was buried in your unconscious without your awareness.
Have you ever gotten an eerie feeling about a person or situation, so eerie that it felt premonitory and you knew you had to change course of action? Perhaps you have felt this when jaunting in a dark forest, traveling by car in a desolate area, or walking down an unlit hallway in an old creaky, dirty, stinky house. You probably can thank your unconscious for this. A lot of people call this a hunch, your instincts talking, your intuition calling, or your gut sending warning signals. Maybe its paranoia and overthinking. Whatever you call it, it acts like a sixth sense.
The evidence for your suspicions and hunches never prefaces your premonition, and it therefore seems crazy and delusional to follow these feelings. Maybe? It is hard to assess these feelings accurately when you need to decide quickly as to whether you should act on them. But I think you don’t need to be a diagnosed paranoiac to experience this. It has happened to all of us at some point or another. Even Leonard Mlodinow in his 2012 book, titled How Your Unconscious Mind Rules Your Behavior, seems to agree that this impulse in humans is not always irrational or wrong.
On page 44 and 45 he says the following:
“I learned long ago that it is often best to follow those hunches. I was twenty, in Israel just after the Yom Kippur War, and went up to visit the Golan Heights, in Israeli-occupied Syria. While hiking along a deserted road I spotted an interesting bird in a farmer’s field, and being a bird-watcher, I resolved to get a closer look. The field was ringed by a fence, which doesn’t normally deter bird-watchers, but his fence had a curious sign on it. I pondered what the sign might say. It was in Hebrew, and my Hebrew wasn’t good enough to decipher it. The usual message would have been ‘No trespassing,’ but somehow the sign seemed different. Should I stay out? Something told me yes… But my intellect, my conscious deliberative mind, said, ‘Go ahead. Just be quick.’ And so I climbed the fence and walked into the field, toward the bird. Soon I heard some yelling in Hebrew, and I turned to see a man down the road on a tractor, gesturing at me in a very animated fashion. I returned to the road. It was hard to understand the man’s loud jabbering, but between my broken Hebrew and his hand gestures, soon figured out the issue. I turned to the sign, and now realized that I did recognize those Hebrew words. The sign said, ‘Danger, Minefield.’ My unconscious had gotten the message, but I had let my conscious mind overrule it.” 
As you can see, had Mlodinow followed his gut, he would have avoided looking like a fool. But is our gut always right? Is it truly like a sixth sense? Can you follow your gut on deciding how to win the lottery? Can you depend on your gut to decide if you have found the love of your life? Can you trust your gut when buying a new car?
What Does Scientific Research Say?
The American Psychological Association in 2018 stated that research suggests that people who are apt to choose their gut feelings over logic, do it because their gut feelings more accurately reflect their true selves. 4 experiments were performed with more than 450 participants, “including local residents, undergraduate students and online survey takers” who had to choose from an array of things such as “different DVD players, mugs, apartments or restaurants.” It is said that the intuitive, gut-driven choosers reported feeling more certitude and authenticity about their choices. 
But should we cast prudence to the wind and act on our feelings in the realm of politics? Well, my gut feeling tells me “no!” and I think our punditocracy would agree. Sagacious political decisions require a lot of self-examination and studying what laws should be upheld and who we should elect.
Can our gut feelings tell us about whether we should exercise and eat healthy today? Your gut might say, “We are too tired and stressed today. Let’s lie on the couch, eat potato chips, and watch cat videos.” Your gut might also say, “Well, we don’t need the sugar rush that will last for such a short time before we feel the languishing, depressing crash that will prevent us from thinking clearly, working efficiently, and feeling well.” I suppose the latter would depend on an active frontal lobe to think about these things before making the conclusion that you should eat well and exercise for the day. But maybe if that health information is ingrained in you, to orient your habits around what that means, your unconscious mind would be hard at work to make that health information cross your mind in a split second for deciding to get up and exercise for the day. You won’t have to try to think about it. It just happens.
Intuition, gut-feeling, or a sixth sense?
I feel the need to distinguish these terms to better determine what we truly mean when we use them.
What exactly is intuition and where does it come from? Intuition must be a type of information-processing unit if intuition is emotion-based and emotions can be a basis for your evaluations on what you have thought and experienced. Intuition and gut-feelings are a part of the cognitive apparatus of predicting what will happen next by perpetually juxtaposing sensory inputs and current experiences with memories and information about past experiences. 
Your brain does this without your effort and acute attention. It comes from the unconscious in a bottom-up fashion. Traditionally, intuitive thinking has been viewed as antithetical to the scrupulous, error-detecting, logical, deliberative process of analytical thinking. A 2015 meta-analysis report from Wiley Online Library reported that these two mechanisms are “uncorrelated” and “independent” from each other. Secondly, rationality is not precisely concomitant with analytical thinking. 
But is intuitive thinking overlapping with analytical thinking? Some like to think so. Perhaps we could say “yes” if you have an unconscious mind making presuppositions ad-infinitum while your conscious self is trying to update your cognitive models and conclusions harmoniously with new observations that contradict older ones. One style of thinking may predominate over the other, or at least the ideal is to trust analytical paradigms more than intuitive ones, but the hidden and un-immediately graspable nature of the unconscious makes it difficult to pinpoint when it occurs.
If all humans are subject to intuitive unconscious forces, then even scientists are not immune to the flaw that can creep into their decision-making processes which are supposed to be objective and bias-free. Then again, science can be self-correcting enough that its replicable test results can churn out something that rigorously supports some hunches that scientists propose. It is likely sophistical on our part to always assume that what emerges from the unconscious can’t be right. This is the stuff whereupon culture remains stable, predictable, and functional, and furthermore, sometimes a culture can be right about something. And what if analytical thinking is somehow subject to backfiring? Perhaps it is linked to some forms of overthinking that cause post-hoc, selfish, agenda-driven rationalizations rather than real honesty about what is going on. Moral dilemmas can be a likely place where this occurs, and analytical thinking in that context could be a neurotic defense mechanism obscuring the real reasons why you made an unconscionable decision. 
Now, what physiological relationship exists between the gut and the brain to generate this unwitting process of knowledge? Science does not seem to tell us that the gut talks to the brain presciently, for instance, about what numbers are going to hit on tonight’s Powerball, or to reveal unshakable facts about reality, like the answers to your anatomy exam you forgot to study for last night. But your gut microbiome, a colony of 10^13-10^14 microscopic entities, can impact a lot of neural development and brain chemistry that can change your course of feeling and action.  A bad diet can make you feel a lot of things you rather would not, and if you feel enfeebled by the bad diet you are consuming, it is easy to predict you will have a bad day at work or the gym.
Psychology professor Linda Rinaman finds that the vagus nerve is the conduit through which the gastrointestinal tract and the brain communicate. The vagus nerve travels throughout the chest and abdomen, surveilling everything involved with the enzymatic breakdown of food, heart rate, blood pressure, infection-resistance and hormonal functions. As a lot of afferent nerve fibers are very active here and the GI tract is significantly larger than the surface of the skin, the GI tract communicates with the brain more than any other organ in the body. The vagus nerve is the longest of the cranial nerves and carries both bottom-up and top-down messages. So, it is not hard to imagine why your gut feelings are so powerful when they strike and take control of your emotions and behaviors, especially when facing troubles and threats. Its protective agenda facilitates decision-making and how you should assess a situation or avoid it entirely. 
If the autonomic nervous system is involved with the bidirectional microbiota-gut-brain relationship and is the chief instrument governing fight-or-flight responses, which occur during stress and threats, it is not surprising that a disequilibrium of the gut-brain axis is causally connected to organic dysfunctions, neurodegenerative disorders and gastrointestinal disorders such as irritable bowel syndrome (IBS) and inflammatory bowel disease. Due to the VN’s role in interoception (awareness of your body’s internality, important for maintaining homeostasis) it can be easily felt as a sixth sense. An advantageous or disadvantageous result is generated from the metabolic molecules/information that are sent through afferent fibers to the central nervous and autonomic system. Stress can modify your gut-based colony of microorganisms important for immunologic, hormonal and metabolic balance. Stimulating the vagal afferent fibers will affect the networks that use monoamine neurotransmitters responsible for regulating
emotion, arousal, and certain types of memory. VN stimulation is becoming more important in the treatment of inflammatory, neurological, and psychiatric conditions.   In that regard it should come as no surprise that stress accompanies your gut feelings about a person, place, or thing being either good or bad.
Is it really the gut that tells us about the future? Do we have a sixth sense?
What else can I say about gut-feelings? When you’re driving on a debris-covered road amid a wicked windstorm, what lets you know that you should get off on the next exit instead of continuing down the highway? You don’t have to think about it, you just do it. If you see a tree fall, but you swerve and miss, it is not hard or debatable to assume that another tree will fall later. That is not having a sixth sense or fortunetelling skill. That is having good deduction skills.
But what about people who claim to have gained knowledge without use of the physical 5 senses? What if a man sits near you on a subway train and you immediately know that he is a murderer? He isn’t odorously offensive nor has bloodstains on his shirt to show that he finished the atrocity before getting on the train. You just suddenly know that he is a murderer. What has always fascinated me is the frequent claim that people knew they found their lifetime lover the moment they met. I guess many would call this extrasensory perception or a psychic ability. But is it truly extrasensory perception, psychic, or anything supernatural? It is hard for me to pinpoint exactly.
The human brain has many uncanny abilities, but conventional wisdom would say that we don’t have paranormal or psychic abilities. The Melbourne School of Psychological Sciences is reputed to have disproved the sixth sense with a study involving 50 participants in total from 4 experiments who were able to perceive differences in images of the same woman, even though they could only see each of those images for 1.5 seconds and were not able to localize or articulate those changes. The study’s foremost researcher was Piers Howe. 
Some professionals have dubbed these split-second, unconscious judgments and deductions as “knowing without knowing.” Aside from the brain’s decision-making, the human body in general also mysteriously has more ways of “knowing without knowing.” Proprioception is another riveting human feature we can study without paranormal assumptions. It enables your coordination, posture, and balance without your fixating on accomplishment of the task. It is the cause for your ability to raise your hand above your head and know it is there with your eyes closed. Proprioceptors enable you to do multiple things as once, such as running and dribbling a basketball. Sensory receptors communicate with the nervous system about joint angle, muscle length, and muscle tension to make you aware of the spatial location of your limbs without fastening your full attention to them. The Golgi tendon organ makes you aware of any muscle tension changes whereas the muscle spindles are responsible for muscle length changes. 
Now onto something that might seem a bit paranormal; scientists have studied alpha waves (electrical oscillations in the brain that have a repeating frequency of roughly 8 to 13 cycles per second when conscious and relaxed) in a laboratory at the California Institute of Technology, in Pasadena. Their experiments revealed that exposure to magnetic forces that are proportionate to the Earth’s magnetic levels can elicit peculiar brain-wave patterns from humans, leading the scientists to think that humans may have a “sixth sense for magnetism” or unknowingly respond to the Earth’s magnetic field. The ability is called magnetoreception and is something that various animals use to voyage the globe. Although, the experiment is thought to lack further substantiation. 
These are just a few examples of the uncanny abilities of the human body and brain that science has yet to understand completely. But let’s postpone making paranormal conclusions for a while.
About the author: Matthew is interested in discussing social psychology, neuroscience, anthropology, sociology, human biology and anatomy, mental health disorders, philosophy, the psychology of religion, and the history of religion. Matthew loves his friends, his family, and his dog named Sampson. You can contact Matthew at email@example.com.
Disclosure statement: I am not a licensed therapist nor doctor. My intention is to not pretend to be either. The information contained in this article is not meant to be accepted instead of a doctor or licensed therapist’s advice. All information contained herein is based on my interpretation of the books and articles I read. My hope and desire is that any troubled person reading this would feel encouraged to get help from a licensed practitioner.
 Leonard Mlodinow, How Your Unconscious Mind Rules Your Behavior, Chp. 2: Senses Plus Mind Equals Reality, pg. 44-45