brain science roundup, vol. III

A quick roundup of recent articles and studies about brain and behavior that intrigued me…

1. Wired asks what it “means” for something to be random. It’s axiomatic among behavioral scientists that humans are “bad” at randomness, seeing patterns where none exist and unintentionally creating patterns when trying to act randomly (a finding that goes back to 1949!). In a way that’s odd, because randomness is happening all the time in the brain; noise is a fundamental feature of neurons.

Relatedly, a recent study found that rats—unlike humans—can be goaded into making random decisions (summary; full article). Rats in the study chose between two options, only one of which would them a food reward for each choice. Unbeknownst to those poor rats, the “correct” food-bearing option was selected by a computer and depended on patterns in their previous selections. With this setup, rats could get the most food only by making truly random selections.

Surprisingly (to me), the rats eventually switched into a “random” decision mode:

When faced with a weak competitor, the animals made strategic choices based on the outcomes of previous trials. But when a sophisticated competitor made strong predictions, the rats ignored past experience and made random selections in search of a reward.

Even more interesting, whether animals were in a “random” or “strategic” mode depended on stress. When researchers cut off norepinephrine, a stress/emotion-related hormone, animals went from random to strategic decision-making (or vice versa, if norepinephrine was introduced). This suggests—extremely tentatively—that the only way to “go random” is to be stressed enough about the (bad) decisions you’re making to give up altogether on making good ones; the rats in this study basically saying “well I can’t win so no sense wasting time trying to, I’ll just pick randomly”. Clearly that wasn’t a conscious decision, but maybe if all those (human) research subjects trying to generate random sequences had been getting shocked and belittled, they would have done a better job.


2. In The Atlantic, David Eagleman talks about two opposing forces: mounting evidence from brain science free will is less “free” than we think, and the idea that the US criminal justice system mandates the assignment of blame.

When a criminal stands in front of the judge’s bench today, the legal system wants to know whether he is blameworthy. Was it his fault, or his biology’s fault? I submit that this is the wrong question to be asking. The choices we make are inseparably yoked to our neural circuitry, and therefore we have no meaningful way to tease the two apart…

That blameworthiness and lack of free will are incompatible was also the central point of his book, Incognito. As I discussed in my recap of the book, Eagleman convincingly argues that volition is a far squishier topic than we think. But then what do we do once we accept that? Eagleman argues for evidence-based sentencing, which relies on actuarial tables and “scientific” evidence with the sole aim to reduce future crime (rather than to punish). It’s already filtering into the courtroom, though, with early returns ranging from “unclear” to “even more discriminatory than current policies” to “maybe not even constitutional” (see here and here). Free will isn’t as free as we think, but it’s much less clear that “evidence-based sentencing” is a solution. I also strongly recommend this Wired article about the “folk psychology” of free will.


3. BPS has a great list of the 10 most controversial psychology studies, which includes both ethical horrorshows and scientifically controversial studies, such as challenges to free will, the malleability of memory, and Bem’s recent demonstration of precognition (does not include JB Rhine’s earlier work on precognition, which I discussed here). A good primer on some of the historical debates in the field.


4. Nazghul Ghandnoosh talks about racial perceptions and how they influence beliefs about justice and punishment:

Whites who associate crime with blacks and Latinos are more likely to support punitive policies – including capital punishment, mandatory minimum sentencing, and trying youths as adults – than whites with weaker racial associations of crime.

5. Neuroskeptic has some fun with the emptiness of study-reporting headlines heralding/demonizing interventions that “change your brain”….since everything changes your brain.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s