Research Spotlights: May 2019

research spotlight

Americans continue to be sedentary despite public health warnings

Recently published research supported by the NCI investigated trends in sedentary behaviors among the U.S. population, including differences by sociodemographic and lifestyle characteristics. Sedentary behavior has been linked to increased health risks, including obesity, diabetes, heart disease, and certain cancers. The Physical Activity Guidelines for Americans, published in 2018 by the U.S. Department of Health and Human Services, recommend less time spent sitting; however, there is little known about how much time Americans actually spend sitting. Importantly, these behaviors vary by age and by sociodemographic factors, which have not been systematically evaluated in the U.S. population.

To fill this knowledge gap, the researchers analyzed data from the National Health and Nutrition Examination Survey (NHANES; n = 51,896) from 2001 to 2016 in four age groups—children ages 5–11, adolescents ages 12–19, adults ages 20–64, and adults ages 65 and older—to track sitting trends in front of TVs and computers and the total daily amount of time spent sitting. Researchers found that most Americans spend at least 2 hours per day sitting and watching television or videos, and this remained stable over time. However, computer screen time outside of work/school increased over time, with at least half of individuals across all age groups using a computer for more than 1 hour per day, and up to a quarter using computers for 3 hours or more. Both adults and adolescents had increases in their total daily sitting time from 2007 to 2016, from 7 hours per day to about 8 for teenagers, and from 5.5 hours per day almost 6.5 for adults. Males of all age groups, non-Hispanic black individuals of all age groups, and individuals who reported being obese or physically inactive were more likely to spend more time sitting compared to other groups.

This research highlights the importance of measuring and understanding the changes in sedentary behavior trends and their contributions to disease risk and disparities in these illnesses in the United States. The results from this study can support the development of more targeted public health campaigns or programs and interventions.

Yang L, Cao C, Kantor ED, Nguyen LH, Zheng X, Park Y, Giovannucci EL, Matthews CE, Colditz GA, Cao Y. 2019. Trends in sedentary behavior among the U.S. population, 2001-2016. JAMA. 321(16):1587-1597.

Scientists identify early visual attention deficits in infants at risk for autism spectrum disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impairments in social interaction, communication, and other behaviors. Research supported by grants from NIMH, the Marcus Foundation, the Whitehead Foundation, and the Georgia Research Alliance examined early attention in infant siblings of children with ASD who are at risk for social and communication delays. Social communication skills emerge in infancy within the context of rich social interactions and require that an infant pays attention to the people and objects around them. Disruptions in acquiring these skills may lead to a decrease in the number and quality of social interactions and learning opportunities, potentially leading to negative effects on social development. There is evidence that social attention is already disrupted in 6-month-old infants who are later diagnosed with ASD; however, less is known about the time prior to 6 months.

Researchers mapped visual and auditory attention from 1 week to 5 months of age in infants at familial risk for ASD (n = 41) and typically developing infants at low risk (n = 39). At 12 months, a subset of participants (n = 40) were administered assessments of social communication and nonverbal cognitive skills. Results revealed that high-risk infants performed worse on attention tasks at 2 and 3 months of age compared to low-risk infants. A significant association between overall attention at 3 months and the developmental outcomes of social communication and nonverbal cognitive abilities at 12 months was observed for both groups.

These findings indicate a critical window, between 2–3 months of age, when high-risk infants are showing vulnerabilities in attention skills, suggesting that the transition from reflexive to voluntary control of visual attention may be disrupted. Additionally, attention skills at 2 and 3 months were associated with developmental outcomes at 12 months, indicating that attention or mechanisms underlying it during this early period may be important for the emergence of social communication. Further research is still needed to compare trajectories of high-risk infants who are diagnosed with ASD to those who are typically developing.

Bradshaw J, Klin A, Evans L, Klaiman C, Saulnier C, McCracken C. 2019. Development of attention from birth to 5 months in infants at risk for autism spectrum disorder. Dev Psychopathol. Apr 23:1-11. doi: 10.1017/S0954579419000233. [Epub ahead of print]

Scientists translate brain signals into speech

Researchers funded through the NIH Brain Research through Advancing Innovative Neurotechnologies® (BRAIN) Initiative, the New York Stem Cell Foundation, the Howard Hughes Medical Institute, the McKnight Foundation, the Shurl and Kay Curci Foundation, and the William K. Bowes Foundation recently published work that is aimed at decoding brain signals into speech. Losing the ability to speak can have devastating effects on patient’s quality of life. Technological advances have enabled many of these patients to communicate through devices that translate head or eye movements into speech, but these technologies are limited to producing speech at ~10 words per minute, while natural human speech occurs at ~150 words/minute. Motivated by this limitation, the researchers sought to improve upon this technology by translating speech directly from the brain.

In this study, speech scientists and neurologists recorded signals from the brains of epilepsy patients with normal speaking abilities while the patients were asked to speak or mime sentences. They then built maps of how the brain directs the vocal tract, including the lips, tongue, jaw, and vocal cords, to make different sounds for each individual patient. These maps were then applied to a computer program that produces synthetic speech. The synthetic speech was then given to volunteers to listen and to transcribe. More than half the time, the listeners were able to correctly determine the sentences being spoken by the computer.

Direct speech synthesis has several major advantages over spelling-based approaches, including an increased vocabulary capability at a more natural speaking rate. Additionally, current alternative communication devices require a significant amount of cognitive effort to learn and use them. This new speech-based brain–computer interface may be more intuitive and easier to learn to use for patients. These research findings represent an important next step in realizing speech restoration for patients with paralysis. In the future, the researchers plan to design a clinical trial involving paralyzed, speech-impaired patients to determine how to best gather brain signal data, which can then be applied to the previously trained computer algorithm.

Anumanchipalli GK, Chartier J, and Chang EF. 2019. Speech synthesis from neural decoding of spoken sentences. Nature Apr;568(7753):493-498. doi: 10.1038/s41586-019-1119-1. Epub 2019 Apr 24.