Cognitive Daily

I don’t need words to think about the shape of a car, or how to throw a football, or the taste of a chocolate chip cookie. In fact, things like that are probably easier to think about without using language. That’s why the strong form of the Sapir-Whorf hypothesis — that language is necessary for conscious thought — doesn’t hold up. But even if language isn’t required for some domains, it’s still possible that it is required for certain types of mental processes. It may even be required for some thoughts that aren’t obviously related to language.

Some research suggests that understanding the thoughts of others — having a theory of mind — is one such process. Many children who are late in learning language are also late in developing a theory of mind. This story illustrates the classic theory of mind test:

Mouse nibbles cheese.
Mouse puts cheese under box A
Mouse leaves room
Cat enters room, moves cheese from box A to box B, and leaves.
Mouse returns.

Where does Mouse think the cheese is?

Very young children will say box B, because that’s where the cheese is now. But at around age 4, they’ll correctly answer box A, since Mouse has no way of knowing that Cat moved the cheese. Older children have successfully developed an important aspect of theory of mind — they understand that Mouse falsely believes the cheese is in box A. But does understanding false beliefs of others require language?

Ashley Newton and Jill de Villiers developed a very clever experiment to test this question. They showed 66 adults two of four silent, language-free videos depicting scenes like the one I described above. While they watched the videos, some of the viewers also had to repeat a series of words spoken to them through headphones. Other viewers tapped out a musical rhythm while watching the videos. Half the videos showed false belief scenarios (where the mouse left the room while the cat moved the cheese), and half the videos should true belief scenarios (where the mouse watched the cat move the cheese). Then they were asked where the mouse thought the cheese was. Here are the results:

When the test was a true belief test, viewers were accurate, whether they were being distracted by the rhythm or the language activity. But viewers who watched the false-belief video while repeating words successfully completed the false-belief task less than half the time. People who repeated rhythms instead of words were nearly as accurate on the false belief task as they were on the true belief task — indeed, there was no significant difference in their performance on the two tests, and they were significantly more accurate than those distracted by the language task.

So repeating words disrupts the false-belief test, not the true-belief test, while repeating rhythm disrupts neither test. Newton and de Villiers say there are a number of aspects of language processing that could be responsible for interfering with the false-belief test, but it’s quite clear that some sort of language processing is necessary in order to reason about false beliefs. So while language isn’t a requirement for all thought, it most definitely appears to be a requirement for some thought.

Newton, A.M., Villiers, J.G. (2007). Thinking While Talking: Adults Fail Nonverbal False-Belief Reasoning. Psychological Science, 18(7), 574-579. DOI: 10.1111/j.1467-9280.2007.01942.x

Comments

#1 Kevin C.
February 14, 2008

This is interesting. I wonder what it means for those with speech or language delays (like myself; I didn’t learn to speak until age four, and in fact learned to read before learning to speak).
#2 Dave Munger
February 14, 2008

That’s a good question, Kevin. I think we’re going to need to do some more research to find out. This study doesn’t show which aspect of language interferes with theory of mind, just that it does. The fact that you could read before you could speak suggests that you understood language, and thus it’s possible that you might have already had a pretty well-developed theory of mind before you started talking.
#3 Nelson Muntz
February 14, 2008

This makes sense. The ancient Greeks were the first to write about catchism — in the original sense of a pedagogical method of teaching children by shouting at them. Shouting alone scares the kids, but it does not engender logical confusion. Shouting at them with words does the trick.

This even works on 18-year-olds. In the US military, newcomers are drilled into blindly accepting the old doggerel, “This is my rifle, this is my gun, this is for shooting, this is for fun.” They never, never, ever catch on later to the fact that, yes, the rifle is a gun, and the doggerel is nonsense.

Fill in the blanks:
Thompson submachine __?__
105mm field __?__
9mm burp __?__
.50 cal Browning Machine __?__
electromagnetic rail __?__
USS battleships’ 16-inch __?__
40mm Bofors antiaircraft __?__
12 guage shot __?__

Helpfully point this out to a veteran and he will still fail to learn. Despite the obvious contradictory evidence, he will fall back on his initial stupidity. Catechism is how teenage boys are turned into cannon fodder.
#4 Ben L.
February 14, 2008

I’m probably missing something, but how do we know a rhythm distraction isn’t simply less distracting than a rhythm distraction? Maybe it isn’t specific to this task.
#5 Patrick
February 14, 2008

I wonder if this implies that the concept of “mind other than my own” is merely a linguistic entity. I’m not sure what the research says about abstract thought, I would think that the ability to think abstractly requires some basic facility with language. If that is so, then perhaps people simply cannot treat “mind other than my own” as an abstraction, and therefore cannot correctly deduce that the mouse does not know that the cheese moved while the mouse was gone.
#6 Dave Munger
February 14, 2008

Ben–

That’s a great question. They tested several different distractions paired with a visual search task in a separate pilot study. The rhythm distraction matched most closely with the language distraction.
#7 Peter Turney
February 14, 2008

There is a meditation exercise in which one tries to stop one’s internal monologue — the continuous flow of words we think to ourselves during most of our waking lives. I don’t know much about meditation, but I try this exercise from time to time, mainly because I’m always surprised at how difficult it is, which makes it intriguing to me. When I succeed at the exercise for more than a few seconds, I notice that I am immersed in the present; I lose my sense of the past and the future. I hypothesize that it is this contact with the past and the future that language brings to (or amplifies in) our consciousness. Perhaps we need language to support our episodic memory and to form plans and explore hypothetical scenarios for the future.

The cat-and-mouse experiment involves access to the past (Where did the mouse put the cheese? Where did the cat move the cheese? Did the mouse see the cat?) and to the future (Where will the mouse look for the cheese?). Perhaps the experiment does not demonstrate that language is required for a theory of mind. I would like to see either (1) a version of the experiment that doesn’t involve memory (past) or planning (future) or (2) further experiments that show language distraction does not interfere with memory and planning.
#8 Hrvoje
February 14, 2008

Another possibility is that language processing is simply a more cognitively intensive task than rhythm repetition, so the effect of the distraction is much bigger and therefore measurable. Also it may require certain brain centers (structured thought?) that is not needed for rhythm processing, but is for solving the false belief problem. So language may not be needed to solve the problem, but instead it hijacks the same underlying brain structure that would normally be used for solving the false belief problem.

I wonder if someone performed similar tests on people who never learned language (either verbal or symbolic). It seems quite difficult to perform these tests on “normal” subjects.
#9 Adam
February 14, 2008

@ #3: Aside from the fact that you obviously have a vested interest in proving the “stupidity” of soldiers, I find it hard to believe that you can take yourself seriously here.

I personally know several friends and family who have served in the Air Force, Army, and Marines. Any of these individuals would, I am certain, have no trouble passing the test you outlined above. In fact, much of what I know about firearms stems from conversation with these people.

They would aptly point out that the doggerel you referred to earlier is a phallic pun, that rifles are a class of gun (and therefore synonymous as you would point out), and that they are a specific type of gun which, incidentally, does NOT appear in your list of guns. None of those count as a rifle, and therefore your test is disingenuous at best.
#10 Peter Turney
February 14, 2008

OK, here’s a version that doesn’t require memory or planning. Silent video 1: Person X is sitting, reading a book, with her back turned to person Y. Person Y is a mime, doing some kind of slapstick visual humor. At the visual punchline of Y’s routine, by coincidence, X laughs at something in her book. Silent video 2: Person X is sitting with a book closed on her lap, looking towards person Y. Person Y is a mime doing some kind of slapstick visual humor. At the visual punchline of Y’s routine, X laughs.

Immediately after the laughter, the experimental subject is asked, “Why did X laugh?” If verbal distraction blocks theory of mind, then the subject should answer, “Because of Y’s funny act,” for both video 1 and video 2.

I predict that verbal distraction will not block theory of mind. Because this experiment does not rely on the subject’s memory or planning, the subject will be able to give the correct answer.

It should be relatively easy to design an experiment that tests my alternative theory, that verbal distraction interferes with memory.
#11 Anon
February 14, 2008

Umm… your first two sentences–is that simply an assertion? Or can you support it?
#12 Brian Mingus
February 14, 2008

What is the explanation for subjects performing less than chance on the verbal distraction false belief task?
#13 ringo
February 15, 2008

Ok, I remember failing this test as a child. Not because I didn’t understand that the mouse was a separate entity, but because I had a pet mouse, and I knew that mice find things by smelling them, not seeing them.

Apparently, success in this task depends on an accurate theory of mind, but not a *too* accurate theory of mind.
#14 Richard Uppheim
February 15, 2008

Slightly disturbing, if other studies corroborate the findings. NewSpeak from 1984 springs to mind.
#15 Michael
February 15, 2008

@ Hrvoje

“I wonder if someone performed similar tests on people who never learned language (either verbal or symbolic). It seems quite difficult to perform these tests on “normal” subjects”

From Saxe et al. (2004:103)
“Siegal and colleagues (Varley & Siegal 2000, Varley et al.
2001) have shown that two dense aphasics with dramatically impaired syntactic processing following strokes, nevertheless can attribute beliefs and even pass a nonverbal false belief task.”

But I don’t know how exactly that nonverbal test looked like. And still even if aphasics master ToM-Tests, this says nothing about the involvementof language in the development of ToM

Saxe,R., S. Carey & N. Kanwisher “Understanding other minds.” Annu. Rev. Psychol. 2004. 55:87-124
Varley R, Siegal M. 2000. Evidence for cognition
without grammar from causal reasoning
and “theory of mind” in an agrammatic aphasic
patient. Curr. Biol. 10:723-26
Varley R, SiegalM,Want SC. 2001. Severe impairment
in grammar does not preclude theory
of mind. Neurocase 7:489-93
#16 Matthias
February 15, 2008

There is an experiment mentioned in “Mind Hacks” (O’Reilly) that involves finding an object in a mock room under the influence of audible input (music or spoken word). It could be shown that there are significant differences between participants who already acquired speech and those who haven’t and under those “speech-enabled” ones there is significant difference in performance when there is some music or spoken word played during the retrieval phase of the experiment. This audible distraction is meant to knock-out/override the speech processing circuits in the brain. The conclusion is that speech is needed to perform this logic task to combine the two factors in order to find the object.
So, to me this experiment already shows that you need speech/language to think “certain thoughts”.
#17 Tony Jeremiah
February 15, 2008

Another interesting study.

I’m not completely convinced about the conclusion that developing a theory of mind depends on language though. Mostly it’s due to my understanding of Allan Baddeley’s working memory model, which explains how visual, verbal, and attention systems interact to encode information into long-term memory (i.e., info lasting more than 30 seconds). It seems possible to suggest that the reason for the data is because the two distraction tasks used unequally disrupt a visual-to-verbal translation process. Specifically, it’s possible that the rhythm distraction does not affect processing of visual info contained in the false/true videos, because such a task does not impact visual information processing. On the other hand, the verbal distraction task affects processing of the false and true belief videos, because ultimately (I’m assuming this–I haven’t looked at the study), participants are reqiured to encode visual information in verbal form, because a verbal response may be required for the task.

Another study should include some visual distraction task to control for the possibility that a visual-to-verbal translation process is involved in theory-to-mind tasks–probably because of a verbal response is required. So that could mean that a theory-to-mind task could ultimately involve mental imagery. Ways to get around this confound might be to do a cross cultural study involving persons who use pictographic languages, such as the Kanji and Kana symbols present in Chinese and Japanese languages.

A developmental perspective might shed some light as well, given that most children learn visually before fully acquiring language. Also, research shows that autistic children (who are known not to have a well developed theory of mind), tend not to have abstract verbs such as think, pretend, make believe, and imagine (all associated with theory-of-mind) to the same extent as other children. So, it is not language, per se, that is the source of the failure to develop a theory of mind. Instead, something else (possibly related to visual processing) might be preventing them from acquiring theory-of-mind related, verbal concepts.

@10 (Peter)

I think you would be correct in that prediction. However, not so much because there’s no reliance on memory or planning. More so because the task seems less demanding on the attention system (which is important in memory formation). A similar (less complicated) task was done with children actually.

Children were asked to look at a picture of an animal (e.g., a horse). The experimenter then covered up the picture with only a part of the animal (e.g., tail) showing. The children were then asked, if another person came along and saw what you are looking at now, would they know what animal it was? Children from 7-11 (in Piaget’s concrete operational stage) were more likely to say Yes (incorrect answer) than children in the formal operation stage (11+). This is an easy task for adults. Also, at least to me, it seems that mental imagery might be involved more so than language.

@12 (Brian)

I’m assuming the data represents the mean of participants from the study. Probably a handful of participants didn’t get any answers correct.
#18 breton
February 15, 2008

I think this is interesting research, but I think your conclusion that “it’s quite clear that some sort of language processing is necessary in order to reason about false beliefs,” is too strong.

It does not show that the task requires language, only that in adults who have learned to use language-based representations to solve similar tasks, disrupting language disrupts the task.

The chicken-and-egg nature of the problem makes testing the Sapir-Worf hypothesis very difficult indeed.
#19 Amanda Owen
February 15, 2008

This line of research is actually very confusing with regard to whether language is necessary. Success at this task & other tasks of TOM (Theory of Mind) develops between 3.5-4.5 and doesn’t seem to be dependant on the verbalness of the task or the way the task is presented. The use of complex syntax – the ability to say two independant propositions – also comes online at this time in typical children. Correlation vs. causation is difficult to distinguish here.

Deaf children born to hearing parents (who have reduced input and poor language outcomes) perform worse on Sally-Anne/change location tasks (the formal name for the mouse-cheese task) than do deaf children born to deaf parents or hearing children born to hearing parents (see work by de Villiers and colleagues). The hypothesized cause of this deficit is a deficit in syntactic processing.

On the other hand, if the cause of this deficit is syntactic, then other populations with syntactic deficits (aphasics, children with specific language impairment) should show similar problems. Children with SLI do not show problems reliably on nonverbal versions of the task -although they do show difficulty with verbal versions and with the syntactic forms. See work by Carol Miller and colleagues.

Training studies and crosslinguistic studies also suggest that this effect is peculiar to English and is not clearly a causal relationship, but rather a correlation. I don’t recall authors offhand but the Training study was done with German speaking children and Tomasello was one of the authors. X-ling work includes Mandarin and German, both of which express mental attitudes as 1 proposition not two, presumably easing the mental load.

Consider: False belief requires greater executive function than true belief. Thus interfering tasks are more likely to interfere with false belief. Also, I agree with an earlier commenter that language tasks may require more cognitive resources than tapping tasks.I wonder if adults could carry out Judy Deloache’s shrinking troll task equally successfully (also requires holding two propositions in mind) while doing the two distractor tasks.

So… I think the last two sentences are too strong for the overall body of evidence (although perhaps not for this paper, since de Villiers does take a strong stance on this topic)
#20 Katy
February 15, 2008

What were some of the other distraction types that were ruled out? I ask because rhythm is something that interests me. Like language, rhythm seems to be a concept that is unique to humans. (Rhythm defined as the way people know and use it, not the definition associated with things like bird songs. I’m not clear on the distinction but I am sure there is one, and it ties in also with human time perception).
#21 Char
February 15, 2008

Ask yourself under what conditions you work best or that you CAN work effectively. I would posit that so long as our mind can treat what it’s hearing as background noise and ignore it — that our ability to concentrate and use our minds effectively remains unimpaired. One example where this can happen: sitting in an area where ALOT of people are talking and the mix of words etc becomes just an incomprehensible din (train station, airport gate, your home during a large family gathering). Another (as the experiment used) is music — even with a pervasive beat that makes your feet tap by themselves. I did my best studying in college with headphones on and Crosby, Stills, Nash, and Young; Chicago; etc. playing quite loudly — enough to cancel out the noise of my dorm.

I would also posit that if the words are distinct enough that your mind can’t HELP but recognize them and spend neuronic(sp?) activity to process them, then – yes — your ability to fully concentrate on the task at hand IS impaired and quite seriously too. Think of the person that drops by your office while you’re trying to do something that needs your attention and keeps gabbing away at you despite your urgent requests to stop and go away.

My 2 cents on a Friday evening….
#22 Hrvoje
February 15, 2008

Michael,

Thanks for the references, very interesting. These seem to undermine some of the conclusions from the main article… Do you know of any study where people with a certain damage could not solve the TOM problem at all, but are otherwise fine? That would possibly localize the center for TOM (if such a thing exists!).

It does make sense that language is key to any significant thinking task (like the one I’m struggling with now), but TOM appears to be a basic one that comes naturally (subconsciously?) as the brain matures. What would be the most basic task cognitive that can only be solved by language?
#23 Tony Jeremiah
February 15, 2008

@22

Re: Do you know of any study where people with a certain damage could not solve the TOM problem at all, but are otherwise fine? That would possibly localize the center for TOM (if such a thing exists!).

**I don’t know if this gets close to answering your question, but Amanda’s comment (@19) about TOM appearing at 3.5-4.5 suggests that most “normal” children under 3.5 can’t solve TOM tasks. So examining the brain activity of children above and below this age period might be important. Actually, upon referencing the textbook I teach from (Berk, 2007), it appears that the ability to inhibit inappropriate responses is correlated with acquisition of false-belief understanding. So my guess is that dpfc maturation is critical.

As an important aside, TOM development involves more than brain maturation. In line with Vygotsky’s sociocultural theory of cognitive development, other research has shown that in cultures where linguistic communication involves infrequent reference to states of mind, children have slower TOM development. This is consistent with research with autistic children (who have TOM difficulties), who tend not to have abstract verbs such as imagine, pretend, and make believe in their vocabulary.

Re:…What would be the most basic task cognitive that can only be solved by language?

**IMO, counting. At around 3, children can engage in counting that appears to be based on language mimicry–they can count a row of five objects, but have no idea what they are saying. This is evidenced by the fact that when asked for one object, they give one item; however, when asked for more than one, they will usually give a larger but incorrect amount. But by age 3.5-4, they understand the principle of cardinality, which is an understanding that the last number in a counting sequence indicates the amount of items in a set.
#24 Theresa
February 15, 2008

Another possibility is that language processing is simply a more cognitively intensive task than rhythm repetition, so the effect of the distraction is much bigger and therefore measurable.

This was my first thought, too.

As a “visual thinker” — i.e. most of my thoughts appear in my head first as pictures (or abstract “shapes” that I have a hard time describing in words) and then I apply words to them — I would be very distracted if I had to say something while watching a video. I prolly wouldn’t have noticed much of the video at all!

There is a meditation exercise in which one tries to stop one’s internal monologue — the continuous flow of words we think to ourselves during most of our waking lives.

I do this, too, sometimes but most of the exercise involves me trying to stop the pictures rather than words.
#25 Hrvoje
February 16, 2008

@23
Good point. Note also that Amanda pointed out that this might be a correlation. This would make sense to me. TOM seems like a very important social skill, too important to be dependent on timely language learning.

Many of us need to draw a picture to understand something (like Theresa probably?). At my work, I’m surrounded with engineers who convey their thoughts best on a white board. Even a chain of events (similar to what is involved in the false belief task) is normally turned into a picture, a sequence diagram.

So it’s hard to tell when language becomes critical (although it is obviously a great tool, that speeds up most of our thinking). I’m still curious as to what is the simplest scenario where language is the only tool. Counting could be one, but as you noted, children count before they understand what they are doing. Also they count with their fingers as well, which turns out to be quite handy for math.
#26 Nomen Nescio
February 16, 2008

Nelson – as Adam pointed out, military recruits certainly do understand the phallic pun in the doggerel. (recruits in boot camp have an acute sense of anything sexual, as well as any kind of scatological humour. i speak from experience on these matters. the former is clear enough, but figuring out the why’s of the latter might make an interesting psych experiment.)

the purpose of the doggerel, other than crude amusement, is to drill in one aspect of military jargon; the soldier’s rifle is not in that loosely defined class of firearms which the military calls “guns”. civilian society uses “gun” differently, but the military has its technical lingo just like any other profession.

(for real confusion, ask a field artillerist about the technical terms involved in that service branch. half of them are outdated French, even today.)
#27 Tony Jeremiah
February 16, 2008

@25

Your question is interesting, and one (I think) that can be made more tractable with an agreed upon definition of language.

A generic definition is a system in which arbitrary symbols are combined to produce an infinite number of meaningful statements. So language can include things such as musical notes, binary code in computers, mathematical symbols, engineering blueprints, or words. So if I’m assuming correctly that by language you mean words, it appears you’re asking at what point words become critical, and, are their situations where only words are used to communicate or solve particular problems?

My suggestion of counting as such a task, is based on the assumption that words are necessary in achieving cardinality, which itself is the principle of understanding what the words associated with numbers (e.g., one, two, three) mean. If one does not achieve cardinality, technically, it should not be possible to count. Indeed though, it does not seem possible to separate the parallel development and association of visual and verbal processing mechanisms and brain regions. In particular, it seems to me that in their totality, the Piagetian conservation (number) tasks (which seem decidedly non-verbal), suggest that visual development may involve learning to see objects as individual entities.

However, this is another chicken-egg issue whereby one cannot tell whether counting words (e.g., one, two, three) leads to the ability to see objects as individual entities, or, whether being able to see objects as individual entities, is contributing to one’s ability to understand counting words. Probably there’s an interaction.

If you’re discussing language from a more utilitarian perspective (i.e., where people use language to solve particular problems), there are various forms of therapy (e.g., cognitive, humanistic, RET) that are primarily based on verbal communication between client and therapist. However, I’m not sure how close this is to your main question.

In relation to your engineering example, although I’m not an engineer (and probably in relation to my initial training in cognitive psychology), I tend to teach my psychology classes via drawing concepts on the board using a mind/mental mapping technically. This basically involves putting concepts on the board (in word form), placing circles around important words, and drawing lines that illustrate which concepts are connected.

Finally, there are certain concepts (quite a few in psychology) that simply cannot be put in (literal) picture form. Self-concept, self-esteem, memory, mood, intelligence. There’s no way to draw such concepts. The closest you can get is illustrating connections between them such as via the mind mapping technique and using real-world examples.

So from my understanding of your question, the best answer to your question might be situations involving the teaching of concepts whereby one cannot (easily) form visual pictures in the mind.
#28 Hrvoje
February 16, 2008

@27
Yes, I was referring to the use of words specifically. My impression is that words are not absolutely necessary, as our brain is a versatile system that will use whatever tool it can to solve problems. We do need abstractions (handles) to juggle concepts in our working memory (5-7 at most?), but I don’t see why some other symbols would not work just fine. As long as there is a unique mapping to the underlying meaning. So I was hoping that someone would prove me wrong, and come up with a simple case where only words can solve a problem.

I think your answer clarifies the issue. Thanks for taking the time to share it. Words are just symbols like any other, but they are in some cases simpler (more compact) in packaging up complex meanings. Perhaps the use of word “language” is a bit misleading in this kind of research (at least it confuses a non-expert like myself

But my point would be that the brain may still be able to work out complex tasks without words, although possibly more slowly. If that is true, there must be more fundamental “structure handling” mechanism in the brain that actually performs the thinking. Some authors (e.g. William Calvin) came up with interesting ideas on this topic.
#29 Tony Jeremiah
February 17, 2008

@28

Not familiar with William Calvin, I’ll have to look up that name.

Check out the literature on the Stroop effect. It’s likely the most studied phenomenon in the history of psychology, and, very appropriate for questions pertaining to the interaction of symbolic systems. In fact, one of your comments “…the brain may still be able to work out complex tasks without words, although possibly more slowly” almost exactly matches an old empirical finding that partially accounts for the traditional Stroop effect (i.e., the finding that it takes longer to name a color when it appears as the ink color of color words relative to naming a color patch). The finding is that when people are asked to name words alone, and colors alone, it takes a longer time to name colors. Even with extensive practice with naming colors, this time difference does not go away.
So naming colors involves some process that is fundamentally different from naming words.

As far as I know, no one has yet accounted for the difference.
#30 Hrvoje
February 17, 2008

@29
Calvin uses Darwin’s approach, and explains the emergence of thought as a result of a selection process where candidate thoughts compete for limited brain resources until one comes out as a winner (on the order of miliseconds, unlike the natural selection that takes millennia). See his Cerebral Code book.

Stroop effect is a good example of this competition. It shows that words can interfere with other ‘handles’. It actually seems that words take over other (less competitive?) alternatives. But I think that the main reason for the delay is that you need to report the colors in the same language as the written words. So whether you want it or not, you will involve the processes that are trying to interpret the written words. Interestingly, if you report the colors in another language (easy for me since English is not my first language!), it is a bit faster faster, possibly since the English “parser” gets turned off and therefore you are less confused by the mismatch. Another thing to try (I did not try it myself): what if one would need to click on an appropriate color box instead of saying the color? Would the interference vanish (word interpretation is out of the thought selection process)? I imagine that the performance would be the same for the matching and non-matching colored words.

Intriguingly, it would appear that word interpretation can cloud the thought process, when it does not match “reality”. I wonder how much of a problem that causes in our everyday life.
#31 Tony Jeremiah
February 17, 2008

But I think that the main reason for the delay is that you need to report the colors in the same language as the written words.

There have been many Stroop effect theories proposed (see Macleod, 1991), and this one happens to be one. And yes, the research does indicate smaller Stroop effects when multilingual persons are asked to report colors in a language different from that in which the words are written. But this is just one aspect of a more general Stroop phenomenon related to response modality (i.e., the nature of the response influences the Stroop effect).

Things get more complicated because there are several types of Stroop effects. A good summary of some of the more basic Stroop-related effects can be found (somewhat paradoxically) in Klein (1964). He found that the magnitude of the Stroop effect linearly increased when you used nonsense syllables (e.g., hfj), rare English words (e.g., eft), common English words (e.g., take), words related to colors but which are not actually colors (e.g., banana), words that are color words (e.g., purple), and words that are color words which are the same as the colors you must name (e.g., green). Each one of those conditions suggests the presence of several types of Stroop effects. Basically, understanding the Stroop effect entails an understanding of reading. Klein’s study (in my interpretation), indicates that orthographic, phonological, semantic, and response modality effects are at the source of various types of Stroop phenomena. So that’s about four different explanations for the Stroop effect alone.

And it gets worse (or better, depending on ones preference for challenges).

More recent research has shown that the Stroop effect varies depending on what letters are manipulated within words.There’s a tendency for more interference for first letters, and less interference for last letters. So you can add a fifth explanatory category to the Stroop effect that concerns manipulating attention.

Another thing to try (I did not try it myself): what if one would need to click on an appropriate color box instead of saying the color? Would the interference vanish (word interpretation is out of the thought selection process)? I imagine that the performance would be the same for the matching and non-matching colored words.

The Reverse Stroop Effect
#32 Hrvoje
February 17, 2008

The Reverse Stroop Effect

There is a paper for everything!
Thanks, Tony.
#33 LA
February 18, 2008

Thank you for this intriguing post. I had to think about your argument for a long time before I really understood that language “most definitely appears to be a requirement for some thought,” seems flawed to me. From what I understood from the study, verbal distraction tends to corrupt the process of encoding language from visual to verbal memory; by no means does this conclude that it is necessary to express something through language. That language distracts the process of translation seems to be the real issue here.

The lack of research on the non-verbal and brain damaged population minimizes your argument. If some adults are distracted between thought processes, does not mean that deaf people will also postulate the incorrect answer? That research has yet to be done, therefore the answer is inconclusive, and your argument is only half supported.

Also, when it comes to rationalization, and theory of mind, I do have to agree with you that some type of language is necessary in order to express it. How can an adult rationalize where the mouse thinks the cheese is hidden? Naturally, through his observation. In this study, the subject’s observation was deterred by the verbal distraction. In all, I think you found evidence that supported your argument. The study was centered on language, as the study you provided showed that “thinking while talking” was a distraction. It was a little far reaching to state conclusively that language was a “requirement” to some thought processes.
#34 Nikhil
February 19, 2008

Instead of words v. music, why didn’t they use verbal visual distraction tasks v. non-verbal visual distraction tasks? For example, having to hit a button every time a noun was flashed in a series of words v. every time a square was flashed in a series of shapes.

Seems like it could cut down on a few variables.
#35 Jeremy
February 19, 2008

I wonder how many of these people just forgot the instructions and said where they thought the cheese was.
#36 Capella
February 20, 2008

I would have a problem with that example.
Why did the cat move the cheese? Why didn’t it just wait for the mouse and ate it?
Why would mouse hide the cheese and leave?

Things like that probably would get my little brain stuck in an ever-spinning circle, and I would fail the test.
#37 Mikhail
February 20, 2008

Rhythmic tapping and verbal tasks are not even comparable in terms of difficulty. The result can easily be interpreted as a difference in the availability of cognitive or attentional resources to the task rather than a language-intrinsic influence…
#38 Tom B
February 20, 2008

“There is a meditation exercise in which one tries to stop one’s internal monologue — the continuous flow of words we think to ourselves during most of our waking lives. I don’t know much about meditation, but I try this exercise from time to time,”

Some techniques (zazen) involve focusing on the breath in a stable posture and returning to it when thoughts arise. “Stopping” internal chatter is indeed very difficult. Sometimes tracing a thought back to understand how it arises is interesting and helpful. This page: (http://www.mro.org/zmm/teachings/meditation.php) via Google gives a nice description of breath practice– easy to try in the privacy of your own home.