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A Battle for Truth: Conscious Versus Subconscious in Decision-making

Anna Dela Cruz's picture

Revered psychoanalyst and authoritative thinker of the late nineteenth and early twentieth centuries, Sigmund Freud, said that the “most complicated achievements of thought are possible without the assistance of consciousness”. One aspect of Freud’s work in unlocking the secrets of the human mind dealt with the cognitive unconscious—cognitive mental processes that influence behavior without the need for active awareness. Examples of the cognitive unconscious at work include automatic behaviors such as biting one’s nails or shaking one’s leg during long periods of sitting still. In addition to habits, recent research suggests that the unconscious mind also has bearing over decision-making and in some cases, is better than conscious thinking.

My initial impressions of the mechanics behind decision-making were that electrical impulses of neurons interacting/communicating with each other somehow eventually result in a physical action. Yet this idea did not allow for the possibility for the emergence of thought. What would prompt the neurons to interact with each other?  In 2008, scientists at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig published a study investigating the brain activity in relation to decision-making. Participants were asked to push a button with either their right or their left hand (1). Both decisions resulted in the same outcome so it did not matter which button they chose but rather that they chose. Participants were free to decide when to push a button but had to note the time they felt they made their decision on which button to choose (1). Computer programs monitored the brain activities of each participant during the exercise. Their data showed that patterns of brain activity in the frontopolar cortex occurred before participants figured out which button to push as well as suggested that certain patterns were predictive of which button they were going to choose in up to 7 seconds before participants felt they made the conscious decision (1). Since the pattern of aforementioned neural activity is associated with unconscious thought, their results imply that decision-making can be heavily influenced by unconscious thought but not determined (1). Since the predictive reliability of the brain activity patterns were not perfect, conscious decisions can still trump that of the unconscious (1). The researchers are also careful to note that their research does not answer where in the brain the final decision is made (1). What intrigues me about these findings is that though the predictability of unconscious neutral activity was not one hundred percent accurate, the subconscious is still at work when faced with decision-making. I think the findings also suggest that subconscious thinking is always “on” in the background while conscious processes, though it has the power to intervene the subconscious, can be “shut off”. My only question for this study is whether dexterity preferences (i.e. right-handedness, left-handedness, and ambidexterity) were taken into account.

While the aforementioned study gauged the influence of the subconscious over decision-making, the separate studies at the University College London (UCL) and at the University of Rochester investigate whether the subconscious has the ability to make the right decision. According to the UCL study, snap decisions attributed to subconscious decision-making (low level function) were far superior in accuracy than conscious decision-making (high level function). Participants in the study were asked to identify the only back-to-front image of a repeated symbol (2). In eliciting only subconscious thought, participants were given between zero and 1.5 seconds to look at an image to make a decision (2). To engage conscious thought, participants were then given a longer to time to look at the images (2). The results showed that the subconscious only condition had an accuracy rate of 95% while the conscious condition had 70% accuracy (2). The researchers rationalized that the conscious portion of the mind tends to over analyze information while the subconscious is more attuned to subtle visual differences. Therefore, the subconscious is more likely to spot which image was rotated while the conscious brain rationalizes itself into thinking that a rotated image is the same as the original.

As our subconscious has the ability to spot subtle visual differences, according to the Alex Pouget of the University of Rochester, it also has the ability to perform complex mathematical calculations without the knowledge of the conscious. In this experiment participants viewed a series of dots on a computer screen. Some of these dots moved in random directions, while a “controlled” number were manipulated to move in one direction. The objective of the participant was to state, upon impression, in which direction the dots were moving (3). To know for sure (consciously) means performing complex mathematical calculations with probability. However, participants looking at the dots to subconsciously gather information were able to identity which direction the dots moved in as though the subconscious was able to perform these mathematical calculations without the awareness of the conscious (3).

If the unconscious has the innate ability to make right decisions while the conscious is more likely to make the wrong one, what does is imply about human understanding of the world and truth? In my observations of human nature, it is “natural” for us to rationalize situations. Is seems that the two levels of mind of our bipartite brains are at constant odds. Though the contributions of the unconscious may be the right answers, they can be overruled by the over rationalization of the conscious. I suppose it is the human tragedy not to know reality as it is, but rather we “know” through subjective interpretations.           

The University of Rochester study reminded me of game on Facebook called Chain Rxn. Players have to exploded as many “randomly” moving dots as possible with one hit by creating (you guessed it!), chain reactions. I found that I had a better chance at producing long chain reactions if I did not think too long to predict the general trend of the dots’ movements than if I actually sat there and consciously thought my actions through. It was better to just go with my gut instinct. The link to the site is provided below, but in order to play you must have a Facebook account.

(1) Max-Planck-Gesellschaft (2008, April 15). Decision-making May Be Surprisingly     Unconscious Activity. ScienceDaily. Retrieved May 16, 2009, from­ /releases/2008/04/080414145705.htm

(2) University College London (2007, January 8). Trusting Your Instincts Leads You     To The Right Answer. ScienceDaily. Retrieved May 9, 2009, from­ /releases/2007/01/070108121659.htm

(3) University of Rochester (2008, December 29). Our Unconscious Brain Makes The     Best Decisions Possible. ScienceDaily. Retrieved May 9, 2009, from­ /releases/2008/12/081224215542.htm


Bimal Kumar Sarkar's picture

Indepth study of Subconcious mind and do research

Does anyone know a institute/university, where work on subconscious mind is being done?

Morgan's picture

The subconscious controls

The subconscious controls what you think, feel, and do. Your conscious has little knowledge, let alone intervention, of the complex processes that take place in your mind and as you can see by the studies explained in this article it actually slows down these processes. When something "pops" into your conscious mind your subconscious has already been working on it for seconds to days. Consciousness developed because it was advantageous to the survival of the human species, but advantageous only in limited amounts.

Serendip Visitor - rahul's picture

scientific basis for conscious / sub conscious

is there a scientific evidence for conscious / sub conscious? are our thoughts related in any way to them? I still wonder why there is no scientific study on this subject apart from the old theory of Sigmund Freud..
Kindly help.

Morgan's picture

There is lots of physical

There is lots of physical evidence of a conscious and subconscious separation in the brain! For example, take a look at professional baseball players. In 1974, Nolan Ryan's fastball was recorded to travel at 100.9 miles per hour. If you work the numbers, his pitch leaves his hand and passes over home plate in four tenths of a second. This is just enough time for light signals to hit the batter's eye, work through the eye's circuitry, and eventually signals activate the contraction of the muscles to swing the bat. Amazingly, all of this happens in less that four tenths of a second which allows the batter to hit the fast ball. But the surprising part is that consciousness takes half a second. The ball travels too quickly for the batter to be consciously aware of it! You don't have to be consciously aware to perform motor acts. The conscious brain is not at the center of the action in the brain, but on a distant edge hearing whispers of the activity.

Matt's picture

Yeah, I believe you're a

Yeah, I believe you're a little bias to the sub-conscious but great study indeed. I have been ruminating over this same subject over the last few days and what I believe is that the conscience trumps the sub-conscience because it's the trainer of the sub-conscious. If you always rely wholly on your sub-conscience it can begin to run wild and get complacent. The only tool that you have to train your sub-conscious mind is your conscious mind. My problem is that my conscious mind has been turned off so long that it just doesn't initiate much which is due to laziness. Change cannot take place in the sub-conscious without the conscious being exercised.

Cara Thrace's picture

I thought this was

I thought this was fascinating, and useful to a certain point. I was curious about the significance of the subconscious for every day situations, and this answered all of my questions.

Paul Grobstein's picture

unconscious and conscious: using both?

Interesting studies indeed, but all set up (unconsciously?) to highlight contexts where the unconscious has advantages?  In what contexts might it be the other way around?