The Stroop Effect
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Originally researched in the 19th century before being formally written about in Germany in 1929, what came to be known as the Stroop Effect gained this label after a paper entitled “Studies of interference in serial verbal reactions” was published in English by American psychologist John Ridley Stroop in 1935.
The version of this concept that Stroop focused on in his initial paper spotlighted the difference in how the brain processes different types of stimuli by asking subjects to look at words and squares on a page and verbally identify what they were looking at.
His initial experiment included three types of visual stimulus: the first were the names of colors printed in black ink, the second were color names printed in different colored ink, and the third were squares of various colors.
In the first test, subjects were asked to read the color words, ignoring the black ink. In the second, they were asked to say the ink colors, ignoring the color words that were written in those ink colors. And in the third, they were asked to say the color of the squares.
The findings of this original experiment indicated that there was a significant response-time lag in the second test: folks were quick to read a word in consistently black ink, and quick to identify the colors of squares, but when they had to ignore the word that was written and say the name of the color in which that word was printed, their verbal responses slowed substantially.
Many permutations of the Stroop Test have emerged in subsequent years, most of which have attempted to refine these findings and more specifically identify what causes this neurological slowdown. No single explanation has been forthcoming, however, and theories abound as to why this seemingly simple task is so difficult for most of us to perform.
One theory posits that because of the nature of reading, and how we cognitively perform the act of reading—the process of learning glyphs, decoding those glyphs, and translating them into concepts—the neural pathways we develop for that particular task are well-worn compared to others, and thus what we might call the strength of that particular mental activity is more potent than the path we traverse to recognize a color, encode that color into a word, and speak that word.
This is similar in some ways to another theory that says what’s called “automaticity” causes this prioritization, rather than our neural pathways.
Reading is an automatic, knee-jerk task that we perform without intending to, this theory posits, and color recognition is perhaps the same—but color naming is not. As a result, we can whip out our reading skills without even meaning to, but this act still consumes some of our cognitive resources, which in turn slows our less-reflexive color-naming processing just enough that we’ll tend to default to reading a word over naming a color, because that’s the information that arrives at the executive portion of our brain, first.
In both cases, the concept of “selective attention” comes into play, which says, in essence, that what we call our attention or focus is applied to what seems to be most important in a given setting, and “importance” can be informed by what we process fastest.
Further back on that same chain of potential influences, our processing prioritization can be nudged by experience, instruction, and bias—performing a string of color-recognition tasks before the main, tested one, for instance, has been shown to result in faster average color processing speeds—but so can our learned or biological predispositions about what’s important in our environments.
So it may be that, because of the general structure of the average human being’s brain, we’re latently predisposed toward reading over color-recognition for whatever reason, but it may also be that many of us are socialized to favor written information because of the world in which we live, where written words in our environments provide us with all kinds of valuable, potentially life-saving information.
It makes sense, then, that we might allocate more cognitive bandwidth to that comparably important info—though again, recognition of colors conceptually seems to be just as fast, if not faster, than our recognition of words. It’s the process of recognizing a color and then converting that information into a word, while also dismissing conflicting, written color-word information, that is slower, in aggregate, than simply reading a word out loud.
Research related to the Stroop Effect has uncovered quite a few helpful insights into how our brains work, in general, as well.
It’s been shown that we favor written words over color-identification more as we age: adults are actually slower to provide the word for the color of ink in these tests than children, which implies that as we grow older, we seem to optimize for certain types of cognitive functions, possibly to make some types of processing more efficient while setting other sorts of processing to the side, as a tradeoff.
It’s also helped support the assertion that we are capable of controlling our own cognitive behaviors, even to the point of training ourselves to overwrite, to some degree, the well-worn ruts in the cognitive road that we’ve carved over the years.
In practice, this means that not only can we bypass our reflexive responses—which in most cases cause us to incorrectly say the written color word, rather than the word for the color of ink used in the context of Stroop Tests—we can also amplify this bypassing capability over time, becoming better at focusing on different aspects of our environments and more capable at switching back and forth between the two, with practice.
All of which implies that the brain remains plastic—stays malleable—even late in our lives, and behaviors that seem to be ingrained or even genetic might have more give to them than we may have otherwise suspected.
Our inhibitory capabilities, in other words, are extensive, even if not always easy or pleasant to utilize.
This has implications far beyond the identification and labeling of colors, and adds further credibility to the well-supported concept that challenging our brains by testing and stretching our neurological boundaries may help us maintain brain flexibility and function throughout our lives.
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