A shot of testosterone straight to the part of the brain that controls sexual motivation made male canaries sing more in order to attract females. But despite the birds' increased romantic enthusiasm, the quality of the singing was worse. Researchers observed that "singing and courting a female is more than just motivation." Read more.
Elsewhere at Hopkins …
The brains of older adults with hearing loss shrink faster. Analysis of data drawn from the Baltimore Longitudinal Study of Aging showed that adults with a hearing deficit of at least 25 decibels lost a cubic centimeter more of brain tissue per year compared to adults with normal hearing. Read more.
Temporary loss of vision was found to improve the brain's ability to process sound. Simulated blindness—a darkened enclosure—resulted in changes in circuitry in the primary auditory cortex in as little as a week's time. The changes improved the brain's ability to hear softer sounds and discriminate pitch. Read more.
STAY ON YOUR FEET
Falls appear to be the leading cause of traumatic spinal cord injuries, which have been increasing in prevalence among American adults, especially older adults. The elderly are four times more likely to die in the emergency room from such injuries, compared to younger adults; if they survive the ER but must be admitted to the hospital, they are six times more likely to die. Read more.
KIDS THESE DAYS
Researchers who analyzed the records of 1,500 HIV-positive teenagers and young adults found that one-third to nearly one-half of them delayed treatment until their disease had progressed. This put them at risk for advanced infections and other complications. Read more.
More than half of children and young adults treated for anxiety do not experience long-term relief from symptoms. Researchers said the findings emphasize the need for better long-term management of anxiety, which affects 20 percent of children in the United States, as well as the importance of rigorous monitoring, even in children who appear free of symptoms. Read more.
Engineers and radiologists are building a searchable image bank of MRI scans from children. The cloud-based digital archive currently holds 5,000 images of brains sorted into 22 brain disease categories such as chromosomal abnormalities, congenital malformations, vascular diseases, and psychiatric disorders. Researchers described the image bank as Google for pediatric brain scans. Read more.
ONE GOOD, TWO NOT SO GOOD
Investigators developed stem cells that can repair damaged retinas in mice. The induced-pluripotent stem cells were derived from human umbilical cord blood, and once injected into the mice found their way to the retinas, where they repaired damaged blood vessels. Read more.
Overweight and obese adults who drink diet soda consume more calories from solid food than comparable adults who drink regular high-calorie sugary drinks, thus negating any reduction in calories from the diet drinks. Researchers believe that artificial sweeteners in the diet drinks may disrupt appetite control. Read more.
Robotic colon surgery costs significantly more than laparoscopic surgery—on average $3,000 more per patient. But a study of outcomes found the robotic procedures did not produce lower complication or mortality rates, nor shorter hospital stays. Read more.