October 1, 2022


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Readers Respond to the February 2020 Issue


As an M.D., I would like to applaud Claudia Wallis’s assessment of the ISCHEMIA and CABANA trials of solutions for particular coronary heart ailments in “The Scenario for A lot less Heart Surgery” [The Science of Wellness]. As she says, those people trials conclude that stenting or bypass surgery for steady coronary artery disease—in which coronary arteries are narrowed—and ablation for atrial fibrillation—in which the coronary heart beats irregularly—may enable patients come to feel greater, but they will never live lengthier.

In actuality, we doctors have been mindful of this concept for quite some time. A trouble we have is imparting it to our patients. I can attest that they never come to feel comfortable with the concept of treating a blockage with medication alone. If they know there is an eighty percent narrowing in one of their coronary heart arteries, they will come to feel greater if it truly is “fixed” by stenting. But by cracking open up a steady narrowing, we would basically enhance the risk of an abrupt closure and would have to give those people patients far more strong antiplatelet drugs than aspirin when the lesion heals just after the process.

The situations that stents and bypasses are going to avoid demise is when patients have unstable lesions that are at risk of occlusion. That’s why these methods do avoid catastrophes in significant-risk patients but not in steady ones, for whom the risk of abrupt artery closure is pretty lower.

There have been many circumstances in the earlier where those people in the media have helped market the fallacy that just after finding a narrowing in someone who is steady, even someone with no signs and symptoms, we can avoid a coronary heart assault simply just by stenting it. I am happy that Scientific American holds by itself to a considerably bigger normal.

BRADLEY J. DIBBLE Speed Cardiology, Ontario

HYDROGEN Electricity

In “The H2 Resolution,” Peter Fairley discusses how hydrogen could be utilized as aspect of initiatives to entirely adopt renewable power. He writes that “solar and wind vitality would break up a limitless resource—water—to build hydrogen for electricity.” But I problem the term “limitless,” in look at of freshwater shortages around the globe. Could the electrolyzers he describes use seawater?

Moreover, I speculate if researchers have speculated whether or not the popular creation of renewable hydrogen would substantially enhance the amount of oxygen in the environment.

EDWINNA BERNAT Shepherdstown, W.Va.

FAIRLEY REPLIES: Viewers are appropriate to look at out for any new technology’s unintended consequences. Researchers’ calculations, however, indicate that a change to wind and solar power—plus the electrolyzers necessary to transform some of their renewable vitality to hydrogen—would use considerably less water than present day fossil-fuel power vegetation. And some of the water employed would be regenerated by fuel cells or turbines that transform hydrogen again into electricity.

The reactions in both equally devices produce one molecule of water for every molecule of hydrogen eaten. Those reactions also take in oxygen, so even nevertheless oxygen is released by electrolyzers throughout hydrogen creation, the technique all round is unlikely to elevate ranges in the environment.


In “The Brain’s Social Street Maps,” Matthew Schafer and Daniela Schiller describe interesting observations that the hippocampus, usually imagined to be specialised for memory alone, might have cells employed for social dynamics. We suggest that this arrangement would describe why many persons with synesthesia, in which senses are mixed up, might make remarks these kinds of as “December is a body fat, stupid guy with a limp, and he is in like with February, who is a jolly and mothering presence.” Curiously, in these kinds of circumstances, if names for two nonsequential months are placed following to each and every other, then two sets of emotions commence blending or clashing unless of course a line is drawn in between them, which stops the conversation. The sensory barrier gets to be a conceptual-metaphorical one.

Calendar synesthesia, noticed in one to 2 percent of the populace, might contain the neural circuitry the authors describe. The calendar envisioned by persons with this condition can get idiosyncratic styles, with months set in specific fonts. Our psychological calendar requires circuits in the still left angular gyrus, crucial for sequence discrimination and connected to the same hippocampal place mobile or grid mobile via a band of fibers: the inferior longitudinal fasciculus.

We suggest that in calendar synesthesia, these connections are strengthened to the place of resembling real photos. For illustration, if a calendar is projected on vertical stripes, topics see moiré interference at the fringes. If the stripes are tilted, they see the calendar as tilted in the opposite direction. If they transform their head to the appropriate, reminiscences of the calendar’s still left facet grow to be inaccessible to them. Musical scales in the Indian melakarta technique, which are categorised into a spatial grid of 72 ragas, evoke highly unique and elaborate emotions and might also make the most of the same map.

ZEVE MARCUS University of California, San Diego

I am mildly on the autistic spectrum, and the report by Schafer and Schiller spoke to me. I am pretty specified that persons with autism have unique social maps (and not just interactions) from those people who do not. I speculate if anyone is doing investigation on how the neural circuitry that the authors focus on could also participate in a job in autism—that is, whether we not only make unique maps but have a absolutely unique way to “analyze” social relationships.


When Schafer and Schiller mention that “the brain has a knack for finding substitute routes,” I am reminded of building scheduling, in which those people routes are the many probable paths through the pursuits that have to be completed to end a job. They can be demonstrated on a diagram connected by arrows indicating which tasks can be executed just after one is concluded. Arriving at a “critical path” in these kinds of a diagram calls for calculating the length of every probable route and picking the one that will get the job completed fastest. Before computer systems, a great engineer, or a group of them, could end challenging initiatives less than price range and on agenda with a hand-drawn diagram.



Chuck Hagel’s January 2020 report “Stop Suppressing Science” [Forum] was a welcome examine at a time when evidence-based coverage making is in fact less than sustained assault. Previous secretary of protection Hagel outlines federal laws to protect countrywide federal government staff members and the scientific approach from politically enthusiastic interference by the executive department and its pals. Let us hope that new regulations in this space are in fact enacted by a foreseeable future, wiser administration.

Legislative action is also necessary, however, to enable researchers who are highly susceptible to repressive steps by state politicians beholden to community (or countrywide) interests. Personnel of public universities or organizations are significantly at risk. A person needs only to remember weather scientist Michael Mann’s ordeals at the arms of Virginia’s attorney basic when Mann was employed at the University of Virginia and the harassment of seismologist Austin Holland by the University of Oklahoma’s administration when he headed the state’s Geological Study.

Weill Cornell Medicine and Scientific American’s Board of Advisers