Our Unconscious Brain Makes The Best Decisions Possible

Fascinating study about the probabilistic operation of our unconscious.

Pouget's extensive earlier work . . . suggested the human brain is wired naturally to perform [statistical] calculations. . . .

"We've been developing and strengthening this hypothesis for years—how the brain represents probability distributions," says Pouget. "We knew the results of this kind of test fit perfectly with our ideas, but we had to devise a way to see the neurons in action. We wanted to see if, in fact, humans are really good decision makers after all, just not quite so good at doing it consciously. . . . It's weird, but people rarely make optimal decisions when they are told the percentages up front." . . .

Shadlen's team watched the activity of a pair of neurons that normally respond to the sight of things moving to the left or right. For instance, when the test consisted of a few dots moving to the right within the jumble of other random dots, the neuron coding for "rightward movement" would occasionally fire. As the test continued, the neuron would fire more and more frequently until it reached a certain threshold, triggering a flurry of activity in the brain and a response from the subject of "rightward."

Pouget says a probabilistic decision-making system like this has several advantages. The most important is that it allows us to reach a reasonable decision in a reasonable amount of time. If we had to wait until we're 99 percent sure before we make a decision, Pouget says, then we would waste time accumulating data unnecessarily. If we only required a 51 percent certainty, then we might reach a decision before enough data has been collected.

Educating Goldfish: Multiple Lines of Intelligence Evolution

From Scientific American:

As is the case with many traits—complex brains and sophisticated cognition have arisen multiple times in independent lineages of animals during the earth’s evolutionary history.

Gándara and Contreras: Rescuing the American Dream

I just finished the new book, The Latino Education Crisis: The Consequences of Failed Social Policies, by Patricia Gándara and Frances Contreras (HUP, out in January). Written in an accessible style but with copious footnotes and references for those so inclined, the book documents where we are now, and where we might go, in our education, and care of, the Latino population. Fast-growing and largely neglected, this population's characteristics are documented in the book with charts, tables, statistics, and heart-wrenching stories about dreams deferred and aborted. I was particularly struck by the portraits the authors make of a number of Latino and Latina youths who overcome barriers, and of those who do not.

In the last few pages of the book, Gándara and Contreras outline a policy agenda to address the need.

• Better health care and access to social services
• Subsidized preschool programs
• Housing desegregation and stabilization initiatives
• Target recruitment and better preparation for teachers
• Immigration policy reform
• Support for dual-language education
• Dropout prevention and college-access programs that support the connection between school and home

The buzz on this book is palpable, and I expect it to be discussed and widely reviewed. I have tapped one of my colleagues to review it for Education and Culture.