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The infant mind’s not-quite “blank slate”
Oct. 30, 2006
Special to World Science
New findings may have clarified an old debate over whether our mental abilities are mainly born with us, or developed through experience, researchers say. An orangutan, one of five extant species of Great Apes,
defined as humans and their closest relatives. All five species
were tested in a new study probing the boundaries between innate
and cultural preferences. (Courtesy Katrin Riedl)
An emerging answer, a study suggests, is that we inherited some basic tendencies from our ape-like ancestors, but different human cultures can either refine or
override those.
The findings are the latest page in a debate that traces roots to ancient
Greece. Philosophers on one side have argued that the newborn mind is a “blank slate” that
acquires distinctive properties only through life experience.
Most scientists by now accept that heredity and environment both help shape shape the mind, but just what each contributes remains very foggy.
To simplify the problem, researchers at the Max Planck Institute for Psycholinguistics in The
Netherlands, who conducted the new study, focused on just one mental skill that they
called central to cognition: spatial memory.
They studied the performance and strategies of great apes, human children and human adults of different cultures on spatial tests.
The researchers found that human skills and strategies varied by culture at least from
eight years of age onward. But there was just one strategy common to human
four-year-olds and apes.
That suggests the great apes and humans inherit similar preferences, but culture molds those of humans to different perspectives and strategies, they added. The findings, they argued, add to growing evidence that cognitive
studies using Western subjects may not represent the full range of human abilities.
The research team identified two strategies as common for spatial problems among the groups they studied.
One strategy is self-centered: locations are described with reference to one’s
self, usually to the left, right, front or back. The other is “environment”-centered: objects are described by their position with respect to each other. An example
is “the ball is in front of the house.”
Apes and young human children prefer the environment-centered strategy; but
adult preferences vary by culture, the researchers wrote in the study, published in this week’s early online edition of
the journal Proceedings of the National Academy of Sciences.
For instance, the scientists observed, environment-centered processing is usual for members of a hunter-gatherer community in Namibia called
≠Akhoe Hai║om (the unusual symbols stand for clicking sounds.) Self-centered processing is typical for Europeans.
The emerging picture, the researchers wrote, is that there exists an “inherited bias toward the allocentric,” or environment-centered, coding, but this “can be
overridden by cultural preferences.”
However, “this override is not a rare or typically European phenomenon,” they added: it also occurs in both industrial and traditional cultures worldwide, including some tribesmen who live just a few hundred kilometers from the
≠Akhoe Hai║om area.
There also exists a third place-coding system, the researchers noted, called “absolute.” In this, places are described in terms of North, East, South or West, or equivalents.
While this technique is occasional for Westerners, speakers of Guugu
Yimithirr in Australia know only it, according to the study’s
lead author, Daniel Haun. “A Guugu Yimithirr speaker would say ‘There’s an ant on your south leg,’”
he and other colleagues wrote in a previous paper in the March 2004 issue of the journal
Trends in Cognitive Sciences.
The “override” theory, Haun and colleagues wrote in the new study, suggests self-centered processing should be harder to learn than environment-centered. Past research suggests this is indeed the case, they added.
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New findings may have clarified an old debate over whether our mental abilities are mainly born with us, or developed through experience, researchers say. The emerging answer, a new study suggests, is that we inherited some basic tendencies from our ape-like ancestors, but different human cultures can either refine or override those tendencies. The findings are the latest volley in a debate that traces roots back to ancient Greece, with philosophers on one side arguing that the newborn mind is a “blank slate” that takes on distinctive properties only as the infant gains experience. Most scientists by now accept that heredity and environment both help shape shape the mind, but just what each contributes remains very foggy. To simplify the problem, researchers at the the Max Planck Institute for Psycholinguistics in The Netherlands, who conducted the new study, focused on just one mental skill that they described as central to human cognition: spatial memory. They studied the performance and strategies of great apes, human children and human adults of different cultures on tests of spatial relationship skills. The researchers found that human skills and strategies on these tests varied by culture at least from 8 years of age onward. But there was just one strategy common to human four-year-olds, along with apes of many species. That suggests the great apes and humans inherit similar preferences, but culture molds those of humans to different perspectives and strategies, they added. The findings, they argued, add to growing evidence that cognitive studies using Western subjects may not represent the full range of human abilities. The research team identified two thinking strategies as common for spatial problems among the groups they studied. One is self-centered: locations are described with reference to one’s self: usually to the left, right, front or back. The other is “environment”-centered: objects are described by their position with respect to each other. An example would be “the ball is in front of the house.” Apes and young human children prefer the environment-centered strategy, also called allocentric; but adults preferences vary by culture, the researchers wrote in the study, published in this week’s early online edition of pnas. For instance, the scientists observed, environment-centered processing is usual for members of a hunter-gatherer community in Namibia called ≠Akhoe Hai║om (the unusual symbols stand for clicking sounds.) Self-centered processing is typical for Europeans. The emerging picture, the researchers wrote, is that there exists an “inherited bias toward the allocentric,” or environment-centered, coding, but this “can be overridden by cultural preferences.” However, “this override is not a rare or typically European phenomenon,” they added: it also occurs in both industrial and traditional cultures worldwide, including some tribesmen who live just a few hundred kilometers from the ≠Akhoe Hai║om area. There also exists a third place-coding system, the researchers noted, called “absolute.” In this, places are described in terms of North, East, South or West, or equivalents. While Westerners use this strategy sometimes, speakers of Guugu Yimithirr in Australia know only it: “a Guugu Yimithirr speaker would say ‘There’s an ant on your south leg,’” wrote Daniel Haun, lead author of the new study, and colleagues in a previous study in the March 2004 issue of the journal Trends in Cognitive Sciences. The “override” theory, Haun and colleagues wrote in the new study, suggests self-centered processing should be harder to learn than environment-centered. Past research suggests this is indeed the case, they added.