Mind reading!

Neuroscientists at the UC Berkeley have used functional MRI technology to determine what someone is looking at just by analyzing their brain patterns.

Others have done this in the past using neural networks, but never with images. Haynes et al. (2007) had participants perform mental addition or subtraction and record what brain activity is occurring first. Then, participants were given numbers and they were able to choose whether to add or subtract, then they gave their answer. Post hoc analyses (long after participants were out of the scanner) lead to neural network models being able to predict using brain activity alone whether participants added or subtracted the numbers.

Gallant and colleagues (2008) have used similar methodology. Participants first had to view objects so researchers could determine brain patterns, then they were able to match up future brain patterns with past scans. While it’s not pure mind reading (since you need prior knowledge), it’s still pretty impressive.

This is good, because bad people don’t have a big database of scans involving brain patterns of previous knowledge. So evil doers will not be able to stick anyone in an fMRI and read their thoughts, thankfully. At least, not yet.

Price, Expectations, and Brain-Supported Lies

A recent article in the Proceedings of the National Academies of the Sciences by Hilke Plassmann and colleagues starts with this abstract:

Despite the importance and pervasiveness of marketing, almost nothing is known about the neural mechanisms through which it affects decisions made by individuals. We propose that marketing actions, such as changes in the price of a product, can affect neural representations of experienced pleasantness. We tested this hypothesis by scanning human subjects using functional MRI while they tasted wines that, contrary to reality, they believed to be different and sold at different prices. Our results show that increasing the price of a wine increases subjective reports of flavor pleasantness as well as blood-oxygen-level-dependent activity in medial orbitofrontal cortex, an area that is widely thought to encode for experienced pleasantness during experiential tasks. The paper provides evidence for the ability of marketing actions to modulate neural correlates of experienced pleasantness and for the mechanisms through which the effect operates.

Essentially, students were placed in an fMRI scanner and drank wines that were similar in price but were told that some wines were more expensive than others. The result? Participants rated the “more expensive” wines are better, and their brains responded appropriately! Orbitofrontal cortex was activated more in response to the more expensive wines, indicating a heightened emotional response (pleasure).

The impact of this is simple: if a product is more expensive, people will gain greater pleasure from purchasing it. This is not a previously unknown result, certainly. People will often justify their more expensive purchases, but this research shows that the brain responds differently to pricier (and therefore “better”) items. Even if you have to lie to yourself that the more expensive product is better, your brain will likely reflect the reality that you’ve constructed. Mind you, this experiment is not testing that, but it is a reasonable hypothesis to draw.

This research is relevant to a big debate going on right now in the home theater world. I just bought a flat-screen TV and have been outfitting my home theater with lots of high definition content. I’ve needed new cabling to accomplish all this, and I can either buy the $100 (!!!) Monster Cables from Best Buy or $5 cables from the Internet. The question that’s been brewing online is which cables are better. Apparently, some audiophiles can’t even tell the difference between a coat hanger and $100 Monster cables, yet people still buy the expensive cables, enjoy them, and claim to be able to hear better sound. Why? This research explains why.

Can you tell the difference?

Hemispherectomies: Yes, they remove a whole hemisphere.

I watched a rerun of House tonight, and a hemispherectomy was performed on the patient of the week. Yes, they remove an entire hemisphere. When it’s done in young patients, they can recover and live surprisingly normal lives. A snippet from a New Yorker article:

As an eight-year-old, Christina played soccer, swam, and did karate. Then she contracted Rasmussen’s encephalitis, a little-understood condition that causes chronic inflammation of the brain. One day at the Jersey Shore, her foot started twitching, and within a few months, as the right side of her brain deteriorated, she was having hundreds of seizures a day. Christina became Johns Hopkins hemispherectomy case No. 30—her surgery took fourteen hours, one of the longest operations Carson has performed. The alterations to Christina’s car are necessary, because she has impaired motor function on her left side. (Each hemisphere of the brain primarily controls the opposite side of the body.) She also lost sight on the left side of each eye, and now wears prism glasses that bring the left field of vision over to the center of the eye. When I met her, she had taken her S.A.T.s and just finished high school, coming in seventy-sixth in a class of two hundred and twenty-five. Last fall, Christina was a freshman at College Misericordia, in Dallas, Pennsylvania, where she’s studying speech pathology.

All that I have to say is that the brain continues to amaze. This was done in an eight year old, so much of the brain is still developing, and that’s a huge advantage. Having this surgery when you’re older is much riskier. But the fact that someone can bounce back from having their brain removed - astounding!

Article on the New Yorker website
Article in PDF form