This free Information Age Education Newsletter is written by David
Moursund and Bob Sylwester, and produced by Ken Loge. For more
information, see the end of this newsletter.
The previous issue of this newsletter (see http://i-a-e.org/newsletters/IAE-Newsletter-2009-31.html
provided an overview of nature, nurture, and tools. It emphasized how
these work together to help us resolve challenging cognitive problems.
This issue focuses on the capabilities and limitations of working
memory, a central brain system.
Biological Capabilities and Limitations
The current US average life expectancy is about 78 years, 30 years
higher than a century ago. Humans could theoretically live for decades
beyond our current life span, but that capability would come at
enormous biological cost. We would need additional back up and
regenerative systems, a fail-safe immune system, protective mechanisms
for additional external and internal dangers, and a much larger
body/brain than we currently have, in order to support all this extra
We've used our considerable cognitive abilities to
develop technologies that compensate for our biological limitations,
and we expend much of our energy (translated into income) to pay for
technologically enhanced food, clothing, shelter, travel, and medical
The biological and technological tradeoff is to balance
cost and benefit—to provide whatever is necessary to carry out the
desired functions, but to not go very far beyond that. Let's explore
one such issue, our ability to effectively process useful space/time
Most animals live in the here and now, so they don't concern
themselves with what's elsewhere, and with past/future events. Our
large forebrain's capabilities evolved to allow us to contemplate and
respond to broader space/time issues—here/there, then/now/later, and
Here and now information has strong sensory
support, and so it's processed relatively easily. Conversely, if a
decision needs to factor in past and possible events, or what's
occurring beyond our sensory range, our brain needs effective long-term
information storage and retrieval capability. That's basically what
memory does, and its loss through dementia or trauma reduces our
existence to the here and now. We lose context, and thus much of what
it means to be human.
Scientists don't completely understand the
underlying neurobiology of how real life events and behaviors translate
into retrievable neuronal network representations. They do however
understand the functional organization of our complex memory system
that processes skills, facts, and events at both the short and long
Working memory (processed by a relatively small number of parietal
and frontal lobe networks) is the functional core of our memory system,
in that it temporary holds and manipulates the information we use
during complex cognitive tasks. It's the biological equivalent of
what's currently visible on my computer screen. Working memory is
supported by an incredible amount of long-term memory (just as what's
on my screen is supported by files on my computer and on the Web).
Working memory's base is what my emotional system has identified as
currently important, and what my attention system is focused on. Memory
and predictive systems add relevant past/future supplementary
As I write this, the information in my working
memory (and on my computer screen) constantly changes as I try to
transform my prior studies/experiences and current thoughts on working
memory into something that will become meaningful to IAE readers. When
I think I've reached that point, I'll place it into my long-term memory
and a permanent computer file.
Now imagine that I’m working at
my computer on this article and I’m interrupted by a lengthy phone
call. What was on my computer screen remained, but what was in my
working memory was disrupted, since I needed to use my working memory
to carry on the phone conversation. Most of what was in my limited
capacity working memory while writing was thus erased during the
Some people are better than others at
multi-tasking. In essence, such people can simultaneously attend to two
or more different tasks. Their working memory quickly moves among tasks
without loosing its task connections.
Controlled attention is
internally driven. It's what I deliberately focus on while working on
this document. Stimulus-driven attention is externally driven—the
disruptive ringing phone, or some flashing text on a screen display.
Most people can control their internally driven attention enough to
quickly check out an external stimulus and determine its level of
urgency. This is a type of multi-tasking. Others may become frustrated
by even a modest disruption when focusing their controlled attention on
Cognitive neuroscientists have discovered that an
average person can simultaneously maintain only about seven units of
information in working memory. (See the 1956 seminal article by George
Miller at http://cogprints.org/730/0/miller.html
We can overcome some of this working memory limitation through
chunking— combining related units of information into fewer more easily
For example, suppose that I want to contact
a close colleague whose business telephone number is 541-346-2468 – 10
units. My mind represents the telephone number with three chunks: area,
company, and office codes. My brain translates “area code” into 541,
“company code” into 346, and 2468 into a remembered “count by twos.”
Chunking can thus be quite personal—memorized or learned to a high
level of automaticity.
Contrast this type of chunking with what
occurs if I’ve stored my colleague’s phone number as #5 in my cell
phone’s list of stored numbers. I can now contact my colleague by
simply pressing 5—and technology has augmented biology.
type of computer-based chunking is a very powerful aid to the human
mind as it works to solve challenging problems. A single chunk, such as
“budget spreadsheet” or “Google” serves to quickly retrieve software or
locate information that’s needed to solve a current problem.
The Overflowing Brain
The highly respected Swedish cognitive neuroscientist Torkel Klingberg
has recently published The Overflowing Brain: Information Overload and
the Limits of Working Memory. (See http://www.sharpbrains.com/blog/2008/11/29/torkel-klingberg-helps-with-overflowing-brain-information-overload/).
He argues that we can best increase our ability to deal with the
extension of information by seeking a reasonable balance between our
ancient brain's limitations and cultural demands.
developed reading, writing, calculators, computers, and other tools to
help overcome biological limitations in working memory. Working memory
is essential to both learning and using tools. Biology and technology
are thus (and have always been) collaborators, and not competitors.
Klingberg's book is an excellent non-technical analysis of a complex
current issue—with good practical advice on how to create a balance
between our biological and technological capabilities/limitations.
You might also want to read Bob Sylwester’s “Educating an Attentive Human Brain”: http://brainconnection.positscience.com/content/246_1.
About Information Age Education,
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museum located in Eugene, Oregon. Current IAE activities include a Wiki
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