Summary: Researchers report declines in verbal reasoning, matrix reasoning and numerical series scores in a large U.S. sample from 2006–2018, while spatial reasoning (3D rotation) showed gains for the years available (2011–2018). Source: Northwestern University The Flynn effect historically describes steady rises in measured IQ across the 20th century—often three to five IQ points per … Read more

Summary: A longitudinal study of nearly 2,000 children found that boys who were regularly exposed to violent television content between ages 3.5 and 4.5 were more likely to report antisocial behaviors in mid-adolescence. These behaviors included physical aggression, theft, threats, involvement in gang fights and weapon use. The study found no comparable long-term associations among … Read more

Summary: Fetal brain overgrowth may help explain why autism varies so dramatically in children. A UC San Diego team grew brain cortical organoids from toddlers and found that larger organoid size and faster prenatal-like growth correlated with more severe social and language symptoms. These results point to embryonic origins of two autism subtypes and could … Read more

Summary: New research shows that cannabinoid signaling can prune synapses and alter the formation of neural circuits in the developing brain. Source: Osaka University. Researchers led by Associate Professor Fumitaka Kimura in the Department of Molecular Neuroscience at Osaka University have identified multiple mechanisms that guide the formation and refinement of neuronal circuits in the … Read more

Summary: A new study reveals how specific genetic mutations can shorten the circadian clock, causing some people to be extreme “morning larks.” These mutations make the internal clock run on an approximately 20-hour cycle instead of aligning with the 24-hour day-night cycle. Source: UC Santa Cruz New research explains how mutations in a key enzyme … Read more

Summary: New research shows that fiber digestion produces short-chain fatty acids—most notably propionate and butyrate—that directly change gene activity through epigenetic modifications and can produce anti-cancer effects. The study mapped how these metabolites alter the regulation of genes that control cell proliferation, differentiation and programmed cell death, processes that are central to limiting tumor growth. … Read more

Summary: Researchers at Umeå University and collaborating institutions report that stress-related epigenetic changes in the CRH gene are associated with increased suicidal behavior in adults and higher psychiatric risk in adolescents. Source: Umeå University New research identifies epigenetic alterations in the corticotropin-releasing hormone (CRH) gene—part of the body’s stress-regulation system—as linked to severe suicide attempts … Read more

Could human suicide have evolutionary roots in self-sacrificial behaviors like those seen in species such as honeybees and ants? A researcher at Florida State University, recognized as one of the country’s leading experts on suicide, is exploring that question. Thomas Joiner, the Robert O. Lawton Distinguished Professor of Psychology, led a group of researchers who … Read more

Researchers at Aalto University and the University of Turku have identified a clear association between obesity and altered opioid neurotransmission in the human brain. Study overview New neuroimaging research shows that obesity is linked with changes in the brain’s opioid system, a key network involved in producing pleasurable and hedonic sensations related to food. The … Read more

Summary: Parents who used marijuana and alcohol were more likely to use a range of disciplinary methods — from nonviolent tactics to corporal punishment and, in some cases, physical abuse — than parents who did not use substances. In this sample, parents who reported using both alcohol and marijuana in the past year had a … Read more