“Zapping” the Brain Affects Moral Judgments
Two nights ago, I caught a fascinating NOVA scienceNow report on a recent study wherein researchers altered individuals' moral judgments via the use of transcranial magnetic stimulation (TMS) to a region of the brain known to be associated with moral processing (right temporoparietal junction; RTPJ). Specifically, RTPJ has been shown to be active when evaluating the beliefs and intentions of an individual's actions. In two separate studies, participants were exposed to four possible scenarios involving the actions of an individual, subsequent to which they made a moral judgment about the permissibility of such an act.
Suppose that you are told that an individual were to pour sugar in the cup of a friend (while visiting a chemical plant). The sugar is stored in a mug labeled "toxic." The four delineated scenarios consist of what the individual thought the contents of the mug were (sugar or toxic powder) and what the actual reality was (sugar or toxic powder). Hence, we have:
(1) The individual thought that the powder was sugar and it was indeed sugar. The friend drinks the coffee and survives.
(2) The individual thought that the powder was sugar but it was a toxic powder. The friend drinks the coffee and dies.
(3) The individual thought that the powder was toxic but it was sugar. The friend drinks it and survives.
(4) The individual thought that the powder was toxic and it was indeed toxic. The friend drinks it and dies.
The key difference between the two studies is that in study 1 TMS was administered prior to the moral judgments being made (offline) whereas in study 2 it was administered during the moral judgments (online). The key dependent measure was how permissible the act of the individual was on a 1-7 scale (forbidden to permissible). The moral judgments of each of the four experimental groups were compared to a corresponding group that received TMS at a control site (i.e., not at the RTPJ).
In both studies, the same statistically significant was found, namely in condition 3 (harm was intended but the outcome was positive), participants who had received TMS in their RTPJ judged the action as more morally permissible as compared to their control counterparts. In other words, the application of TMS to the RTPJ disrupts individuals' abilities to accurately ascribe intentionality in judging the moral behaviors of another.
This paradigm strikes me as particularly promising in that it goes beyond the more "passive" neuroimaging techniques (e.g., fMRI) that have slowly diffused into economics and marketing (neuroeconomics and neuromarketing). Specifically, rather than merely mapping differential neuronal activation patterns in various regions of the brain, TMS offers the opportunity for non-invasive experimental manipulations of the brain. I eagerly await the consumer-related findings that might arise via this paradigm (two of the leading consumer neuroscientists are Carolyn Yoon and Baba Shiv; see also Garcia & Saad, 2008 for a discussion of evolutionary neuromarketing).
Update: Shortly after I put up the post, my colleague William Tooke advised me that Rebecca Saxe (one of the coauthors of the study in question) gave a TED talk on this exact work. Speaking of TED, I am happy to announce that I'll be speaking at the upcoming TEDxConcordia event on February 19th. If you are in the Montreal region, try to make it! ”
—The Nature and Nurture of Consumption by Gad Saad, Ph.D. Psychology Today
Geological detectives are piecing together an intriguing seafloor puzzle. The Indian Ocean and some of its islands, scientists say, may lie on top of the remains of an ancient continent pulled apart by plate tectonics between 50 million and 100 million years ago. Painstaking detective work involving gravity mapping, rock analysis, and plate movement reconstruction has led researchers to conclude that several places in the Indian Ocean, now far apart, conceal the remnants of a prehistoric land mass they have named Mauritia. In fact, they say, the Indian Ocean could be “littered” with such continental fragments, now obscured by lava erupted by underwater volcanoes.
The Seychelles, an archipelago of 115 islands about 1500 kilometers east of Africa, are something of a geological curiosity. Although a few of Earth’s largest islands, such as Greenland, are composed of the same continental crust as the mainland, most islands are made of a denser, chemically distinct oceanic crust, created midocean by magma welling up beneath separating tectonic plates. Geologists think they separated from the Indian subcontinent 80 million to 90 million years ago.
But those islands might not be so unique. Researchers from Norway, Germany, and Britain, writing in Nature Geoscience, now suggest that the Indian Ocean is harboring other fragments of ancient continental crust. Those fragments, the researchers say, lie buried beneath more recent oceanic crust erupted by underwater volcanoes.
A team of scientists has taken the heart cells of a rat, arranged them on a piece of rubbery silicone, added a jolt of electricity, and created a “Franken-jelly.” Just like a real jellyfish, the artificial jelly swims around by pumping water in and out of its bell-shaped body. Researchers hope the advance can someday help engineers design better artificial hearts and other muscular organs.
Any physics student knows that light travels in a straight line. But now researchers have shown that light can also travel in a curve, without any external influence. The effect is actually an optical illusion, although the researchers say it could have practical uses such as moving objects with light from afar.
It’s well known that light bends. When light rays pass from air into water, for instance, they take a sharp turn; that’s why a stick dipped in a pond appears to tilt toward the surface. Out in space, light rays passing near very massive objects such as stars are seen to travel in curves. In each instance, light-bending has an external cause: For water, it is a change in an optical property called the refractive index, and for stars, it is the warping nature of gravity.
For light to bend by itself, however, is unheard of—almost. In the late 1970s, physicists Michael Berry at the University of Bristol in the United Kingdom, and Nandor Balazs of the State University of New York, Stony Brook, discovered that a so-called Airy waveform, a wave describing how quantum particles move, can sometimes bend by a small amount. That work was largely ignored until 2007, when Demetri Christodoulides and other physicists at the University of Central Florida in Orlando generated optical versions of Airy waves by manipulating laser light, and found that the resultant beam curved slightly as it crossed a detector.
How did this self-bending work? Light is a jumble of waves, and their peaks and troughs can interfere with one another. For example, a peak passing a trough cancels each other out to create darkness; a peak passing another peak “interferes constructively” to create a bright spot. Now, imagine light emitted from a wide strip—perhaps a fluorescent tube or, better, a laser whose output has been expanded. By carefully controlling the initial position of the wave peaks—the phase of the waves—at every step along the strip, it is possible to make the light traveling outward interfere constructively at only points on a curve and cancel out everywhere else. The Airy function, which contains rapid but diminishing oscillations, proved an easy way to define those initial phases—except that the resultant light would bend only up to about 8°.
Now physicists Mordechai Segev and colleagues at Technion, Israel Institute of Technology, in Haifa say they have a recipe for making light self-bend through any angle, even through a complete circle. The problem with the Airy function, says Segev, is that the shape of its oscillations specify the right phases only at small angles; at angles much greater than 8°, the shape becomes a crude approximation. So his group turned to Maxwell’s equations, the 150-year-old quartet of mathematical formulas that describe the propagation of electromagnetic waves such as light. After laborious mathematics and guesswork, the researchers found solutions to Maxwell’s equations that precisely describe the initial phases required for truly self-bending light, as they report this week in Physical Review Letters.