By tagging neurons with molecular “barcodes,” researchers have mapped connections among thousands of neurons in the mouse brain with unprecedented speed and resolution. The approach could expand understanding not only of the layout of elaborate networks in the brain, but also how the brain functions, what happens when there is dysfunction and how neurodegenerative diseases progress.

The racial gap in maternal mortality is narrowing, driven largely by climbing death rates of white women with no more than a high school education and declining rates for college-educated Black women, new research shows. For Black women with less education and for both Black and white women giving birth at later ages, maternal mortality rates increased, according to researchers from the University of Michigan, Harvard University and National Association to Advance Black Birth.

Endometrial cancer is the most common gynecologic cancer in the United States and is one of the few cancers in which survival rates have steadily declined over the last few decades. The most aggressive subtypes are a significant driver of that trend: uterine papillary serous carcinoma accounts for just 10% of diagnoses but nearly 40% of deaths.

Nearly 1 in 5 teens in the United States is obese, putting their long-term health at serious risk. Obesity in adolescence leads to many deleterious medical conditions including diabetes, high blood pressure, sleep apnea, and mental health struggles with low self-esteem and depression. Understanding patterns of obesity and weight-loss efforts in U.S. adolescents is critical for shaping effective clinical and public health interventions. Yet, data remain sparse on whether and how adolescents attempt to lose weight.

Depression or ADHD? Neatly delineated diagnoses fail to do justice to the infinitely complex reality that they refer to, argues Eiko Fried in a new paper for JAMA Psychiatry. His proposal: to map the underlying mechanisms of mental health problems using a Mental Health Atlas.