Decision in daily life is not a simple process

Perception is simply experiecing the world through our senses. Everyday we process sensory information to guide useful behavior, like searching for your car keys in a pile of keys. Or, if you have experiences playing badminton, which is a super fast-paced sport, you’d frequently run into instances where you have to determine wehther the shuttle lands inside, outside, or on the court line. This is an example of a process called perceptual decision-making because you make decisions based on what you see using your visual senses. As such it is a central aspect, or even some call it a “window” to understanding our cognition.

In the research world of visual decision-making, it’s been known that people are biased by their previous choices when they make decisions. Simple behavioral experiments demonstrated this. These experiments, often long and boring 💤, invovled people sitting in front of a computer screen and repeatedly make a decision in response to the stimulus they see. For example, a visual simulus can be a cloud of dots either dominantly moving towards the right or left. Every time when the stimulus appears, people have to make a speeded response on whether it’s moving rightward or leftward.

In many of these cases, it’s been shown that what people chose previously, those decisions accumulated into a bias when they make the next decision even when the successive stiumulus are uncorrelated. That is, if you decided that those dots were moving rightward, then there’s a higher likelihood that you would choose rightward again. Anyway, it’s all facinating and reveals a lot about how we huamn beings navigate the uncertain world. One can dive as deep into the research rabbit hole as they wish to understand this.

But these studies have traditionally focused on one person only. By doing this, you are essentially assuming that humans are isolated “heads” out and about experiencing the world. In other words, the physical world we experience everyday is not just us mentally processing a specific sensory information. It’s more sophisticated than that. For instance, when searching for your key, you might have remembered discussing with your mom where it was last found. Or, you might have searched together with your mom, while observing where she’s looking of or even facial expressions to gain more information about the whereabouts of the key. What we experience everyday is not only processing these surrouding sensory stimuli but also interactions with other people.

A creative appraoch

And this is what my project is all about. I included the element of social interaction in this classical experiment to better understand perception and behavior. In other words, I extended this individual setup to a dyadic one, to see how, given what we already know about choice history bias, whether observing your dyadic partner chooses would in turn influence what you choose and vice versa.

This experimental methodology we designed in the research domain of choice history and decision-making is new, however the concept is not so new. The idea goes back to what’s called the embodied cognition, which suggests that how we think and behave are shaped by bodily interactions. For example, when you look at where your friend is looking at, you might develop some understanding about what your friend intends to do. Or you smile back when a stranger smiles at you.

Basically our behavior emerges from our real-time interactions with the surrounding environment. It’s kind of radical to think about our brain and cognition in this way, because it has not always been that way. Rather it’s this idea that our brain generates behaviors, or our brain is separated from our body, that has traditionally dominated the thinking.

Results and impact

So what we did was we created a joint perceptual task and collected behavioral data from people grouped in dyads. Our results indicated that people do not ignore other’s choices when they make decisions.

A research study like this almost never brings immediate changes to the society or world at large in ways that you can see with your own eyes. I mean, even if there’s merit to our results, in real life we’re not bombarded with similar visual information every second.

However, I’d be doing a disservice to myself to think that all the sweat, pain and tears that go into the study were not worthwhile. Some impact I see this study brings to the academic community are as follows:

• The joint design allows for a systematic comparison with the findings on choice history bias from those of the single-participant designs. Moreover, this method is generalizable across various contexts and populations e.g, Human-AI interaction. Since humans treat computers as social actors, what if, say, a virtual assistant consistently reports to you the wrong information, does that change the way you trust or interact with it?

• First to document social interaction influencing choice history bias effect! That said, the implications extend to other scenarios. Going off tangent here, but I wonder how often this choice bias effect is seen in political groups. People are divisive perhaps because they are locked in an echo chamber that breeds biases.

• Publication in Nature Scientific Reports. Hey, might get included in the textbooks one day, right? You never know.

Takeaways

• Multiple iterations is always needed until the task is fully functional and replicable- being able to handle deep frustrations is part of the process.

• The practice of synthetic data simulation is always, not only a great sanity check on data integrity, but also a excellent tool to build a solid understanding of the analysis process.