THE TIME THAT COUNTS
“nUltrasound Meditation” (Advances), Lucy Tu reports on a study by Brian Lord of the University of Arizona and his colleagues on the use of brain stimulation to improve mindfulness, published in the journal Frontiers in Human Neuroscience. The article is thought provoking. Pioneering work at the University of Wisconsin-Madison and elsewhere using functional magnetic resonance imaging and other techniques has been instrumental in attempting to elucidate the neurophysiological correlates of deep meditation experience. Now Lord and his team are adding targeted ultrasound stimulation of the brain’s default mode network (DMN) to their tools of potential value in that effort.
Most practitioners of deep meditation practices welcome these studies. But a word of caution is in order for those who, like the study authors and Tu, use descriptions of the “subjective effects” of deep meditative states. Personal, as well as “scientific” biases can enter. Among the subjective effects of ultrasound stimulation mentioned in the article, I was most concerned with the phrase “distorted sense of time” (which mirrored the language used in the study). Seasoned meditators’ relatively ordinary experience of the “non-linearity” of time is certainly different from the everyday experience of the relative world in which we live. But which of these senses of time is “real” and which is “distorted”? If, as some suspect, spacetime itself turns out to be subject to the laws of quantum physics, perhaps a better description would be “distorted” than “alternative.”
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THOMAS LONG SCOTTSDALE, ARIZ.
“A word of caution is in order for those who use descriptions of the ‘subjective effects’ of deep meditative states. Personal bias can enter.”
—Thomas Long, Scottsdale, Ariz.
LIFE IS A BAG
As a longtime student and practitioner of pathology, I found Bethany Brookshire’s essay “The human body is made of bags” (Forum; June 2024) a fun and engaging look at anatomy. To carry his analogy further, every anatomical “pouch,” from the smallest vesicle to the largest outer surface, has openings and doors. Most, if not all, life processes are enabled in these openings.
On a macro scale, mouths, noses, pores, eye lenses, anuses, etc. are all our interactions with the outside world. At the organ level, these holes allow the exchange of nutrients, gases, toxins, electrolytes, and therefore everything we consume and excrete. Microscopically, cells, vesicles, and all types of enclosures have openings, which are usually controlled transporters. After all, function follows form at every level.
JAMES EASTMAN MADISON, WIS.
THERE ARE MODELS AROUND YOU
“Cosmic pareidolia,” Phil Plait (Universe), points out that humans’ tendency to interpret random visual patterns as something familiar often results in our seeing faces. But such phenomena are not limited to faces or even vision. I have a tile on the bathroom floor that shows a very believable deer head from one angle and a crocodile head, leg and foot from another. A soft breeze in the trees or quiet background sounds can be whispered voices that cannot be clearly understood or music that sounds familiar.
JOHN RUSS BY EMAIL
GOLDEN TOURING KEY
“How Many Routes,” by Heinrich Hemme (Progress; July/August 2024) presents Henry Ernest Dudeney’s classic 1917 traveling salesman puzzle. The “golden key” to solving the puzzle is usually ridiculous, but just try to find it! We’ve only sketched it here In the parts of the road that have to be traveled in all possible ways, that is, in those parts that are connected to the cities by only two roads one), but it also offers us the fun of building that path out of mixed paths.
Years ago a friend asked me about a variation of the “knight’s turn” problem, in which a chess knight starts on a square of his choice and jumps through all the remaining squares without repeating a square. Would this task be possible on a smaller rectangle than the standard 8×8 checkerboard? Given the knight’s strange movement, it was not obvious that a turn would be possible in such a rectangle. A slightly tarnished version of the gold key above, which required some extra work, showed the solution for the 4×5 and 3×4 rectangles. For others there was no solution.
DAVE E. MATSON PASADENA, CALIF.
COLD COMFORT
“Taking a step,” Jesse Greenspan (Advances; June 2024), reports on research into the perceived benefits of cold water swimming. For those who, like me, consider cold water swimming a near-death experience, the humble cold shower offers an interesting alternative.
Cold showers are a form of hormesis, a phenomenon in which stress that is harmful in high doses has a beneficial effect in low doses. As with cold water swimming, data showing the benefits of cold showers are weak, but the well-being and invigorating dimensions are widely accepted. And at least by slowly adjusting the heat of the water the temperature jump can be minimized. Perhaps most importantly, the technique is available at home to most people 24/7.
RICHIE LOCASSO HEMET, CALIF.
THE BIGGEST BUZZ
I enjoyed reading it”Time keeping” (Progress; June 2024), by Meghan Bartels about the spring 2024 emergence of two periodical cicadas, 13-year-old Brood XIX and 17-year-old Brood XIII.
Here in the western suburbs of Chicago, every morning the cigar party began in the distant “Star Trek phaser” 13-year-old insect drone and some individual local buzzes from 17-year-olds. Within hours, any favorite tree on site was a cacophony of rock concert sound, up and down as thousands of people sang along.
LORINDA GUENTHER-WRIGHT CHICAGO
CLARIFICATION
“The severe toll of hypochondria,” Joanne Silberner (Dec 2024), referred to the same condition as “somatic symptom disorder” and “somatic system disorder.” These terms are used synonymously, but somatic symptom disorder is the official diagnosis in the latest edition. Diagnostic and Statistical Manual of Mental Disorders.
MISTAKE
“nThe fate of hybrid chickadees,” by Rebecca Heisman The first photo of a grasshopper should be credited to Teresa Kopec/Getty Images, and the last photo of one should be credited to GeoStills/Alamy Stock Photo.
“Buried at sea,” Jaime B. Palter (Dec. 2024), should say that early results from a marine carbon dioxide removal field trial in Nova Scotia’s Halifax Harbor suggest that the trial moved additional carbon from the atmosphere into the ocean.
“nWhen the Horse became a Runner,” by William T. Taylor (December 2024), a caption incorrectly described Novoil’inovskiy’s location. It is in Kazakhstan.
