The perception of taste is remarkably complex, not only on the tongue but in organs throughout the body.Think for a minute about the little bumps on your tongue. You probably saw a diagram of those taste bud arrangements once in a biology textbook — sweet sensors at the tip, salty on either side, sour behind them, bitter in the back.But the idea that specific tastes are confined to certain areas of the tongue is a myth that “persists in the collective consciousness despite decades of research debunking it,” according to a review published this month in The New England Journal of Medicine. Also wrong: the notion that taste is limited to the mouth.The old diagram, which has been used in many textbooks over the years, originated in a study published by David Hanig, a German scientist, in 1901. But the scientist was not suggesting that various tastes are segregated on the tongue. He was actually measuring the sensitivity of different areas, said Paul Breslin, a researcher at Monell Chemical Senses Center in Philadelphia. “What he found was that you could detect things at a lower concentration in one part relative to another,” Dr. Breslin said. The tip of the tongue, for example, is dense with sweet sensors but contains the others as well.The map’s mistakes are easy to confirm. If you place a lemon wedge at the tip of your tongue, it will taste sour, and if you put a bit of honey toward the side, it will be sweet.The perception of taste is a remarkably complex process, starting from that first encounter with the tongue. Taste cells have a variety of sensors that signal the brain when they encounter nutrients or toxins. For some tastes, tiny pores in cell membranes let taste chemicals in.Such taste receptors aren’t limited to the tongue; they are also found in the gastrointestinal tract, liver, pancreas, fat cells, brain, muscle cells, thyroid and lungs. We don’t generally think of these organs as tasting anything, but they use the receptors to pick up the presence of various molecules and metabolize them, said Diego Bohórquez, a self-described gut-brain neuroscientist at Duke University. For example, when the gut notices sugar in food, it tells the brain to alert other organs to get ready for digestion.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Premature babies especially benefited from skin-to-skin contact, and women tended to respond more strongly than men did.A hug, a handshake, a therapeutic massage. A newborn lying on a mother’s bare chest.Physical touch can buoy well-being and lessen pain, depression and anxiety, according to a large new analysis of published research released on Monday in the journal Nature Human Behaviour.Researchers from Germany and the Netherlands systematically reviewed years of research on touch, strokes, hugs and rubs. They also combined data from 137 studies, which included nearly 13,000 adults, children and infants. Each study compared individuals who had been physically touched in some way over the course of an experiment — or had touched an object like a fuzzy stuffed toy — to similar individuals who had not.For example, one study showed that daily 20-minute gentle massages for six weeks in older people with dementia decreased aggressiveness and reduced the levels of a stress marker in the blood. Another found that massages boosted the mood of breast cancer patients. One study even showed that healthy young adults who caressed a robotic baby seal were happier, and felt less pain from a mild heat stimulus, than those who read an article about an astronomer.Positive effects were particularly noticeable in premature babies, who “massively improve” with skin-to-skin contact, said Frédéric Michon, a researcher at the Netherlands Institute for Neuroscience and one of the study’s authors.“There have been a lot of claims that touch is good, touch is healthy, touch is something that we all need,” said Rebecca Boehme, a neuroscientist at Linkoping University in Sweden, who reviewed the study for the journal. “But actually, nobody had looked at it from this broad, bird’s eye perspective.”The analysis revealed some interesting and sometimes mysterious patterns. Among adults, sick people showed greater mental health benefits from touch than healthy people did. Who was doing the touching — a familiar person or a health care worker — didn’t matter. But the source of the touch did matter to newborns.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

The conventional method for chest compressions doesn’t have a great success rate. Doctors are pumping it up with a high-tech plunger.In 1988, a 65-year-old man’s heart stopped at home. His wife and son didn’t know CPR, so in desperation they grabbed a toilet plunger to get his heart going until an ambulance showed up.Later, after the man recovered at San Francisco General Hospital, his son gave the doctors there some advice: Put toilet plungers next to all of the beds in the coronary unit.The hospital didn’t do that, but the idea got the doctors thinking about better ways to do CPR, or cardiopulmonary resuscitation, the conventional method for chest compressions after cardiac arrest. More than three decades later, at a meeting of emergency medical services directors this week in Hollywood, Fla., researchers presented data showing that using a plunger-like setup leads to remarkably better outcomes for reviving patients.Traditional CPR doesn’t have a great track record: On average, just 7 percent of people who receive it before getting to the hospital are ultimately discharged with full brain function, according to a national registry of cardiac arrests treated by emergency medical workers in communities across the country.“It is dismal,” said Dr. Keith Lurie, a cardiologist at the University of Minnesota Medical School who treated the plunger patient in 1988.The new procedure, known as neuroprotective CPR, has three components. First, a silicone plunger forces the chest up and down, not only pushing blood out to the body, but drawing it back in to refill the heart. A plastic valve fits over a face mask or breathing tube to control pressure in the lungs.The third piece is a body-positioning device sold by AdvancedCPR Solutions, a firm in Edina, Minn., that was founded by Dr. Lurie. A hinged support slowly elevates a supine patient into a partial sitting position. This allows oxygen-starved blood in the brain to drain more effectively and to be replenished more quickly with oxygenated blood.The three pieces of equipment, which fit into a backpack, cost about $20,000 and can be used for several years. The devices have been separately approved by the Food and Drug Administration.About four years ago, researchers began studying the combination of all three devices used in tandem. At this week’s meeting, Dr. Paul Pepe, a longtime CPR researcher and the director of Dallas County’s emergency medical services, reported results from 380 patients who could not be revived by defibrillation, making their odds of survival particularly bleak. Among those who received the new CPR method within 11 minutes of cardiac arrest, 6.1 percent survived with brain function intact, compared with just 0.6 percent who received traditional CPR.He also reported significantly better odds for a subgroup of patients who had no heartbeat but had random electric activity in their heart muscles. The typical odds of survival for people in those circumstances are about 3 percent. But the patients in Dr. Pepe’s study who received neuroprotective CPR had a 10 percent chance of leaving the hospital neurologically intact.Last year, a study carried out in four states found similar results. Patients who received neuroprotective CPR within 11 minutes of a 911 call were about three times as likely to survive with good brain function as those who received conventional CPR.“This is the right thing to do,” Dr. Pepe said.A couple of years ago, Jason Benjamin went into cardiac arrest after a workout at a gym in St. Augustine, Fla. A friend took him to a nearby fire department, where trained workers deployed the neuroprotective CPR gear. It took 24 minutes and multiple defibrillations to revive him.After he recovered, Mr. Benjamin, a former emergency medical technician himself, was amazed to learn about the new approach that had saved his life. He read the studies and interviewed Dr. Lurie. The three-part procedure had several complicated names at the time. It was Mr. Benjamin who came up with the term neuroprotective CPR “because that’s what it’s doing,” Mr. Benjamin recalled, adding that “the focus was on protecting my brain.”Dr. Karen Hirsch, a neurologist at Stanford University and a member of the CPR standards committee for the American Heart Association, said that the new approach was interesting and made physiological sense, but that the committee needed to see more research on patients before it could formally recommend it as a treatment option.“We’re limited to the available data,” she said, adding that the committee would like to see a clinical trial in which people undergoing cardiac arrests are randomly assigned to conventional CPR or neuroprotective CPR. No such trials are happening in the United States.Dr. Joe Holley, the medical director for the emergency medical service that serves Memphis and several surrounding communities, isn’t waiting for a larger trial. Two of his teams, he said, were getting neurologically intact survival rates of about 7 percent with conventional CPR. With neuroprotective CPR, the rates rose to around 23 percent.His crews are coming back from emergency calls much happier these days, too, and patients are even showing up at fire stations to thank them for their help.“That was a rare occurrence,” Dr. Holley said. “Now it’s almost a regular thing.”