<p>The conclusions drawn in Inoue &amp; Matsuzawa's (2007) study, which seems to be <a href="http://goo.gl/yUAMT">available here</a>, are suspect. First off, the sample sizes (6 chimp, 9 human subjects) are simply too small to draw good inferences about working memory, at least about human working memory, but as I imagine chimps are somewhat expensive subjects, c'est la vie.</p>

<p>Secondly, and more worryingly, the study design itself seems to have a real problem: Matsuzawa does not reveal how many hours of practice either group of subjects have had, but presumably, the humans have not had any practice, while it is explicitly noted that the chimps have had some. The mother-offspring pairs practiced the numerals task from offspring age 4, and then the block task from offspring age 5. Even if we ignore the sample size problems and take the reported results at face value, we are still left with a situation where the mother chimp Ai underperformed the humans, who in turn underperformed the offspring chimp Ayumu--also suggestive of a training effect.</p>

<p>This strikes me as a problem for Matsuzawa's claim, because we know that the ultimate limit of task-specific human memory span is very high compared to a task-general baseline. For instance, Ericsson, Chase and Faloon (1980) reported a case study of a subject who increased their memory span from 7 to 79 in 230 hours of practice, and one need look no further than the <a href="http://www.world-memory-statistics.com/National_Records_Memory_Competition.pdf">world memory records</a> to see that the lack of control for practice seriously undermines Matsuzawa's claim about this unexpected "relationship" between chimp and human WMC.</p>

<p>A more restrained interpretation of the evidence presented in the article would suggest that sufficiently well-trained chimps can outperform untrained humans on the particular task. Any conjecturing about "evolutionary trade-offs" on the basis of these findings seem unwarranted to me, but that would have been the case even if these results had been ironclad.</p>

<h3>References</h3>

<ul>
<li>Ericsson, K. A., Chase, W. G., &amp; Faloon, S. (1980). Acquisition of a memory skill. Science, 208(4448), 1181–1182. doi:10.1126/science.7375930</li>
<li>Inoue, S., &amp; Matsuzawa, T. (2007). Working memory of numerals in chimpanzees. Current Biology, 17(23), R1004-R1005.</li>
</ul>

CC BY-SA 3.0
2013-03-28T16:47:59.863Z
2013-03-29T04:13:28.717Z
2013-03-29T04:13:28.717Z
Christian Hummeluhr
<p>High working memory is associated with greater ability to learn meanings of abstract symbols, such as is required to do mathematics. I would be highly skeptical of a claim that there is a trade-off between WM and general intelligence.</p>

<blockquote>
  <p>Ian M. Lyons, Sian L. Beilock, Beyond quantity: Individual differences
  in working memory and the ordinal understanding of numerical symbols,
  Cognition, Volume 113, Issue 2, November 2009, Pages 189-204, ISSN
  0010-0277, 10.1016/j.cognition.2009.08.003.</p>
</blockquote>

<p>Under some circumstances, high WM seems to be associated with poor problem solving under pressure, but not with poor problem solving in general.</p>

<blockquote>
  <p>From poor performance to success under stress: Working memory,
  strategy selection, and mathematical problem solving under pressure.
  Beilock, Sian L.; DeCaro, Marci S. Journal of Experimental Psychology:
  Learning, Memory, and Cognition, Vol 33(6), Nov 2007, 983-998. doi:
  10.1037/0278-7393.33.6.983</p>
</blockquote>

CC BY-SA 3.0
2013-02-22T19:33:59.730Z
2013-02-22T19:33:59.730Z
baixiwei
<p>The answer hinges on the definition of working memory.  If we look at synthetics (people with synesthesia who have impressive massive visual memory correlations to time, numbers, etc) definitely <strong>not</strong>.  They are worse in mathematics and stimulation will trigger unrelated memories.  Synthetics with obsessive compulsive disorder that obsess about their personal memories are constantly cataloging everything they do.</p>

<p>On the other hand, the information-processing models by which we define intelligence hinge on the information storage capacities of working memory.  Sufferers of ADHD show a 10 point drop in IQ because they are unable to persist towards more abstract goals, like learning multiplication tables, and get distracted.  This is also what happens in older adults and women hitting menopause (Barkely, Adult ADHD).</p>

CC BY-SA 3.0
2015-06-22T22:28:08.237Z
What is OCD? and OTOH...?
draks ...
CC BY-SA 3.0
2013-03-28T21:07:34.347Z
2015-06-23T22:15:14.853Z
2015-06-23T22:15:14.853Z
Indolering
<p>It looks like there is a developmental relationship between WM and general IQ:</p>

<p>Fry, A. F., &amp; Hale, S. (1996). Processing speed, working memory, and fluid intelligence: Evidence for a developmental cascade. Psychological science, 7(4), 237-241.</p>

<p>Cole, M. W., Yarkoni, T., Repovš, G., Anticevic, A., &amp; Braver, T. S. (2012). Global Connectivity of Prefrontal Cortex Predicts Cognitive Control and Intelligence. The Journal of Neuroscience, 32(26), 8988-8999.</p>

CC BY-SA 3.0
2013-02-21T08:04:35.940Z
2013-02-21T08:04:35.940Z
Cheatboy2
<p>No. Different parts of the brain are responsible for different functions, and the brain would not spontaneously reorganize based only on a improved WM. </p>

<p>Memory is a huge factor in intelligence, and improving WM would likely result in increased scores on intelligent tests, and in general is a good thing.  </p>

<p>References:</p>

<p><a href="http://www.nature.com/neuro/journal/v7/n1/abs/nn1165.html">Increased prefrontal and parietal activity after training of working memory</a> </p>

CC BY-SA 3.0
2013-02-20T03:52:15.823Z
I don't disagree with you, but having some references to back up your assertions couldn't hurt.
Chuck Sherrington
CC BY-SA 3.0
2013-02-20T08:15:18.363Z
I am sure there are references in the field of developmental psychology demonstrating that WM _could be_ a good predictor for general IQ, but I don't remeber them... some specialist in this topic ? Anyway, at the pure logical level, the fact that chimps are better at WM tests *is not a demonstration of Matsuzawa's hypothesis*.
Cheatboy2
CC BY-SA 3.0
2013-02-20T10:08:35.850Z
Both the Wechsler scale and the old Binet-Simon test as well as some tests used for clinical purposes have a subtest which is essentially a WM capacity test: remembering rows of numbers, repeating them forwards and backwards. How well people do on this subtest is thus directly related to the IQ score they will get.
Ana
CC BY-SA 3.0
2013-02-20T23:17:11.037Z
@Ana, the presence of working memory on an IQ test doesn't mean that working memory contributes to language and problem solving abilities (i.e. the higher order thinking skills).  Chimps are terrible compared to humans at such things, yet chimps are superior on the working memory task.
Kenshin
CC BY-SA 3.0
2013-02-20T23:18:32.427Z
@Cheatboy2, what is Matsuzawa's hypothesis?
Kenshin
CC BY-SA 3.0
2013-02-20T23:20:25.030Z
@nycynik, thanks for your answer. Your reference unfortunately merely states that your brain can adapt to working memory training.  It doesn't say whether such adaptations could inhibit problem solving and language abilities.
Kenshin
CC BY-SA 3.0
2013-02-21T08:03:06.753Z
@Chris, by _Matsuzawa's hypothesis_ I mean the quoted text in your question. By the way, I hardly understand how (and why) working memory would inhibit problem solving and language.
Cheatboy2
CC BY-SA 3.0
2013-02-21T20:13:16.980Z
@Chris - I could not actually find anything that specifically shows the relationship between WM and language inhabition.
nycynik
CC BY-SA 3.0
2013-02-20T03:50:50.890Z
2013-02-20T04:02:27.820Z
2013-02-20T04:02:27.820Z
nycynik
<p>According to the Fox News article <a href="http://www.foxnews.com/story/0,2933,314681,00.html#ixzz2LFidMEVW" rel="noreferrer">"Chimps Smarter Than Humans in Memory Test"</a> chimps were able to significantly outperform humans in a simple working memory task.  I quote one part of the article in particular:</p>

<blockquote>
  <p>Matsuzawa speculated
  there was an evolutionary tradeoff between this kind of sharp memory
  and the higher mental functions seen in humans, such as our advanced
  capability for language.</p>
</blockquote>

<p>Could this "trade-off" mean that training to improve working memory could cause your brain to adapt to such training at the expense of language and problem solving abilities? </p>

<p><a href="http://goo.gl/yUAMT" rel="noreferrer">Matsuzawa's 2012 article in Current Biology</a></p>

<intelligence><evolution><animal-cognition><working-memory>
Does an exceptional working memory inhibit intelligence?
Kenshin
# Does an exceptional working memory inhibit intelligence?

(Asked by: username_0 on 2013-02-18)

According to the Fox News article ["Chimps Smarter Than Humans in Memory Test"](http://www.foxnews.com/story/0,2933,314681,00.html#ixzz2LFidMEVW) chimps were able to significantly outperform humans in a simple working memory task. I quote one part of the article in particular:

> Matsuzawa speculated
> there was an evolutionary tradeoff between this kind of sharp memory
> and the higher mental functions seen in humans, such as our advanced
> capability for language.

Could this "trade-off" mean that training to improve working memory could cause your brain to adapt to such training at the expense of language and problem solving abilities?

[Matsuzawa's 2012 article in Current Biology](http://goo.gl/yUAMT)

**Tags:** intelligence, evolution, animal-cognition, working-memory


---

## 5 answers

### Answer by username_6 on 2013-02-20. Score: 9 | Accepted answer

No. Different parts of the brain are responsible for different functions, and the brain would not spontaneously reorganize based only on a improved WM.

Memory is a huge factor in intelligence, and improving WM would likely result in increased scores on intelligent tests, and in general is a good thing.

References:

[Increased prefrontal and parietal activity after training of working memory](http://www.nature.com/neuro/journal/v7/n1/abs/nn1165.html)

> **Comments:**
> **username_7**: I don't disagree with you, but having some references to back up your assertions couldn't hurt.  
> **username_5**: I am sure there are references in the field of developmental psychology demonstrating that WM _could be_ a good predictor for general IQ, but I don't remeber them... some specialist in this topic ? Anyway, at the pure logical level, the fact that chimps are better at WM tests *is not a demonstration of Matsuzawa's hypothesis*.  
> **username_8**: Both the Wechsler scale and the old Binet-Simon test as well as some tests used for clinical purposes have a subtest which is essentially a WM capacity test: remembering rows of numbers, repeating them forwards and backwards. How well people do on this subtest is thus directly related to the IQ score they will get.  
> **username_0**: @username_8, the presence of working memory on an IQ test doesn't mean that working memory contributes to language and problem solving abilities (i.e. the higher order thinking skills).  Chimps are terrible compared to humans at such things, yet chimps are superior on the working memory task.  
> **username_0**: @username_5, what is Matsuzawa's hypothesis?  
> **username_0**: @username_6, thanks for your answer. Your reference unfortunately merely states that your brain can adapt to working memory training.  It doesn't say whether such adaptations could inhibit problem solving and language abilities.  
> **username_5**: @Chris, by _Matsuzawa's hypothesis_ I mean the quoted text in your question. By the way, I hardly understand how (and why) working memory would inhibit problem solving and language.  
> **username_6**: @Chris - I could not actually find anything that specifically shows the relationship between WM and language inhabition.  

---

### Answer by username_1 on 2013-03-28. Score: 12

The conclusions drawn in Inoue & Matsuzawa's (2007) study, which seems to be [available here](http://goo.gl/yUAMT), are suspect. First off, the sample sizes (6 chimp, 9 human subjects) are simply too small to draw good inferences about working memory, at least about human working memory, but as I imagine chimps are somewhat expensive subjects, c'est la vie.

Secondly, and more worryingly, the study design itself seems to have a real problem: Matsuzawa does not reveal how many hours of practice either group of subjects have had, but presumably, the humans have not had any practice, while it is explicitly noted that the chimps have had some. The mother-offspring pairs practiced the numerals task from offspring age 4, and then the block task from offspring age 5. Even if we ignore the sample size problems and take the reported results at face value, we are still left with a situation where the mother chimp Ai underperformed the humans, who in turn underperformed the offspring chimp Ayumu--also suggestive of a training effect.

This strikes me as a problem for Matsuzawa's claim, because we know that the ultimate limit of task-specific human memory span is very high compared to a task-general baseline. For instance, Ericsson, Chase and Faloon (1980) reported a case study of a subject who increased their memory span from 7 to 79 in 230 hours of practice, and one need look no further than the [world memory records](http://www.world-memory-statistics.com/National_Records_Memory_Competition.pdf) to see that the lack of control for practice seriously undermines Matsuzawa's claim about this unexpected "relationship" between chimp and human WMC.

A more restrained interpretation of the evidence presented in the article would suggest that sufficiently well-trained chimps can outperform untrained humans on the particular task. Any conjecturing about "evolutionary trade-offs" on the basis of these findings seem unwarranted to me, but that would have been the case even if these results had been ironclad.

### References

* Ericsson, K. A., Chase, W. G., & Faloon, S. (1980). Acquisition of a memory skill. Science, 208(4448), 1181–1182. doi:10.1126/science.7375930
* Inoue, S., & Matsuzawa, T. (2007). Working memory of numerals in chimpanzees. Current Biology, 17(23), R1004-R1005.


---

### Answer by username_2 on 2013-02-22. Score: 9

High working memory is associated with greater ability to learn meanings of abstract symbols, such as is required to do mathematics. I would be highly skeptical of a claim that there is a trade-off between WM and general intelligence.

> Ian M. Lyons, Sian L. Beilock, Beyond quantity: Individual differences
> in working memory and the ordinal understanding of numerical symbols,
> Cognition, Volume 113, Issue 2, November 2009, Pages 189-204, ISSN
> 0010-0277, 10.1016/j.cognition.2009.08.003.

Under some circumstances, high WM seems to be associated with poor problem solving under pressure, but not with poor problem solving in general.

> From poor performance to success under stress: Working memory,
> strategy selection, and mathematical problem solving under pressure.
> Beilock, Sian L.; DeCaro, Marci S. Journal of Experimental Psychology:
> Learning, Memory, and Cognition, Vol 33(6), Nov 2007, 983-998. doi:
> 10.1037/0278-7393.33.6.983


---

### Answer by username_3 on 2013-03-28. Score: 3

The answer hinges on the definition of working memory. If we look at synthetics (people with synesthesia who have impressive massive visual memory correlations to time, numbers, etc) definitely **not**. They are worse in mathematics and stimulation will trigger unrelated memories. Synthetics with obsessive compulsive disorder that obsess about their personal memories are constantly cataloging everything they do.

On the other hand, the information-processing models by which we define intelligence hinge on the information storage capacities of working memory. Sufferers of ADHD show a 10 point drop in IQ because they are unable to persist towards more abstract goals, like learning multiplication tables, and get distracted. This is also what happens in older adults and women hitting menopause (Barkely, Adult ADHD).

> **Comments:**
> **username_4**: What is OCD? and OTOH...?  

---

### Answer by username_5 on 2013-02-21. Score: 3

It looks like there is a developmental relationship between WM and general IQ:

Fry, A. F., & Hale, S. (1996). Processing speed, working memory, and fluid intelligence: Evidence for a developmental cascade. Psychological science, 7(4), 237-241.

Cole, M. W., Yarkoni, T., Repovš, G., Anticevic, A., & Braver, T. S. (2012). Global Connectivity of Prefrontal Cortex Predicts Cognitive Control and Intelligence. The Journal of Neuroscience, 32(26), 8988-8999.


---

