The decision making process: Do we make rational decisions?

The decision making process: Do we make rational decisions?

10 Min.
By the Bitbrain team
July 26, 2018

We make thousands of decisions every day in all areas of our life, from the most simple, mechanical and irrelevant decisions such as what to have for breakfast, until important and far-reaching decisions. Although we might think all were thoughtful rational decisions, a high percentage of these choices are not… but do we really know how our brain works when we make a decision? Do we have a strictly rational decision making process?

What is a decision making process? How does it work?

In recent years, neuroscience, along with other fields such as psychology and conductive economy, have been opening a new way of understanding how we act and make decisions. 

The classical and rational decision making model is a multi-step process based on an orderly path that starts with a problem, includes a decision tree and logic evaluation of the cost/benefit, and produces logically sound decisions. However, a very simplified and intuitive decision model was proposed by Genco in 2013, including its strengths and weaknesses. This model explains, in a more realistic manner than the rational model, how people think, decide, and act in the real world.

This model of the decision making process comprehends four steps:

purchase decision making model

  1. Filtering and processing of information to extract what is relevant for the task.
  2. Determine the value and meaning of the information relevant to the task.
  3. Deliver and analyze the information to make a decision
  4. Act and behave to move forward with our decision.

The first two steps operate at a non-conscious level (non-rational), and the third and fourth at conscious levels (rational). Note how clearly bounded rationality is. Let's take a look at the decision maker and these steps with more details.

Step 1: Information processing

Our senses receive more than 11 million bits of information per second, but our conscious brain can only assimilate 50 bits/second (Zimmerman, M. (1989))

A well-known example of this limited capability of consciously perceiving our surroundings is the following experiment:

Unknown Object

This experiment was created in 1999 by psychologists Christopher Chabris and Daniel Simons. It demonstrated that when people were focused on counting how many times the ball was passed around the white team players, the participants’ brains filtered the information on the black team players. As a result, more than 60% of participants were not able to see the person in a gorilla suit who appears among the players.

This experiment demonstrates how the non-conscious layer of the brain decides which information is being consciously processed or not. More concretely, attentional processing is responsible for this decision. There are two types of attentional processes that must be differentiated:  bottom-up and top-down.

  • Bottom-up information processing is an exogenous attentional process. This means that it is directed by external factors that stand out due to their inherent properties, which make them exceptionally different from other elements of the context (this is called saliency). These are attentional changes executed automatically, directed by properties and physical characteristics of the stimulus. For example, in the picture, the green T activates our bottom-up attention simply because it is clearly different

Bottom up information processing

  • Top-down information processing, on the contrary, is an endogenous attentional process. This processing is directed by human expectations and/or intentions, and therefore the selective process is based on previous knowledge of the task. Attentional changes are thus controlled in a volitional manner as a function of cognitive expectations, requirements of the task and/or established goals. 
    For example, when looking at a picture of the famous “Where’s Wally?” or “Where’s Waldo?” collection, our attention is probably directed to red and white stripes. These stripes are not prominent stimuli per se, but we have previous knowledge on the sweater that Wally/Waldo is wearing: one with red and white stripes. In this way, our non-conscious considers these stripes to contain valuable information and directs its conscious attention to them.

Top-down information processing

Step 2: Determine meaning and value

It is normal to think that the recognition process of stimuli is fast, automatic, and only depends on our senses. This means for example that, if a dog crosses in front of us, we believe that we can see it and recognize it because our senses detected it. As if our senses told the brain: “Hey! That’s a dog in front of you!”. 

However, the process is a bit more complex. Cognitive neuroscience has demonstrated that our senses provide input (shapes, colors, shades, etc.), and then our brain, non-consciously, provides meaning and value. To this end, the brain uses clues or elements of the processed information (pieces of information) that are associated with other concepts and ideas. Thus, if our senses perceive something shaped like a dog, that sounds like a dog and behaves like a dog, our brain says “this thing perceived by our senses is a dog”.

Thanks to this, a child that has only seen a pig in a book is capable of recognizing the real animal during a trip to a farm. But also, sometimes two people can give very different meanings to the same thing.

The dress that became a viral internet sensation in 2015, when viewers disagreed over whether the dress was black and blue, or white and gold, was a result of the different ways of processing information and giving meaning to it. People that supposed (probably non-consciously) that shading affected the picture, saw the dress as white and gold. Those who believed the picture was taken under artificial lighting saw the dress as black and blue.

white and gold dress that became a viral

Besides providing meaning to what we perceive with our senses, our brain also provides value to it. For example, when we see the Coca-Cola logo, our brain visually recognizes it. But not only that. Our brain also provides value to what we see: it’s not only a refreshment, it’s much more. 

This is a result of our experience with the product and also of all the investments made in publicity by the brand. Publicity builds non-conscious associations between, for example, the Coca-Cola brand and the concept of happiness.

Step 3: Deliberate and analyze

Once our brain non-consciously establishes the information, its meaning and with what value we are going to manipulate it, our best-known process starts: the rational process. It involves several cognitive tasks such as recover memories, interpret the past, anticipate the future, plan, generate intentions, evaluate alternatives, make judgments, simulate, solve problems, calculate or reason.  

Given that this process is conscious, during many years, the study of human behavior focused on this part, creating the rational model for decision making (homus economicus). Nevertheless, the reality is that when we reach this point, our non-conscious brain has already decided for us which information is going to be processed, how it is going to be interpreted, and what is its assigned value. 

Step 4: Act and learn 

After these three steps (which are actually much more complex), our brain executes the course of action and experiments a reward. But this value will not be remembered 100%, as only a share of this is saved, the remembered reward.

Learning occurs thanks to this remembered reward, which will modify our decision making when a similar situation occurs. On one hand, learning can activate (or not) new top-down processes, as we have already learned that a specific type of information is either interesting or not. On the other hand, the experimented reward influences the reward attributed by us, and also the conscious analysis process.

decision making model

In summary, the human brain is a learning organ; it contains information utilized to guide our behavior and therefore adapts to the surroundings more efficiently and quickly each time.

This decision making model also accommodates very effectively the processes involved in problem identification through solution and problem-solving. It would be interesting if not only each decision but also its consequences could be modeled. This would require the ability to predict the sequence of actions to be carried out and put them into practice to obtain potential solutions. 

This is still not possible without considering the individual decision making experience of each person, but it would indeed be very useful to learn how to make decisions and choose the best possible option (effective decision and optimal decision). Let science and technology advance then!

If we really want to learn more about our human nature, we should consider not only conscious processes (the most obvious and easy to study), but also we should try to understand all previous, underlying non-conscious processes.  Although there is still much more to discover, the advances in neuroscience, psychology, and neurotechnology help us to know a bit more about us each day.

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