(Press-News.org) The width of blood vessels in the retina, located at the back of the eye, may indicate brain health years before the onset of dementia and other deficits, according to a new study published in Psychological Science, a journal of the Association for Psychological Science.
Research shows that younger people who score low on intelligence tests, such as IQ, tend to be at higher risk for poorer health and shorter lifespan, but factors like socioeconomic status and health behaviors don't fully account for the relationship. Psychological scientist Idan Shalev of Duke University and colleagues wondered whether intelligence might serve as a marker indicating the health of the brain, and specifically the health of the system of blood vessels that provides oxygen and nutrients to the brain.
To investigate the potential link between intelligence and brain health, the researchers borrowed a technology from a somewhat unexpected domain: ophthalmology.
Shalev and colleagues used digital retinal imaging, a relatively new and noninvasive method, to gain a window onto vascular conditions in the brain by looking at the small blood vessels of the retina, located at the back of the eye. Retinal blood vessels share similar size, structure, and function with blood vessels in the brain and can provide a way of examining brain health in living humans.
The researchers examined data from participants taking part in the Dunedin Multidisciplinary Health and Development Study, a longitudinal investigation of health and behavior in over 1000 people born between April 1972 and March 1973 in Dunedin, New Zealand.
The results were intriguing.
Having wider retinal venules was linked with lower IQ scores at age 38, even after the researchers accounted for various health, lifestyle, and environmental risk factors that might have played a role.
Individuals who had wider retinal venules showed evidence of general cognitive deficits, with lower scores on numerous measures of neurospsychological functioning, including verbal comprehension, perceptual reasoning, working memory, and executive function.
Surprisingly, the data revealed that people who had wider venules at age 38 also had lower IQ in childhood, a full 25 years earlier.
It's "remarkable that venular caliber in the eye is related, however modestly, to mental test scores of individuals in their 30s, and even to IQ scores in childhood," the researchers observe.
The findings suggest that the processes linking vascular health and cognitive functioning begin much earlier than previously assumed, years before the onset of dementia and other age-related declines in brain functioning.
"Digital retinal imaging is a tool that is being used today mainly by eye doctors to study diseases of the eye," Shalev notes. "But our initial findings indicate that it may be a useful investigative tool for psychological scientists who want to study the link between intelligence and health across the lifespan."
The current study doesn't address the specific mechanisms that drive the relationship between retinal vessels and cognitive functioning, but the researchers surmise that it may have to do with oxygen supply to the brain.
"Increasing knowledge about retinal vessels may enable scientists to develop better diagnosis and treatments to increase the levels of oxygen into the brain and by that, to prevent age-related worsening of cognitive abilities," they conclude.
###
Co-authors on the study include Terrie E. Moffitt and Avshalom Caspi of Duke University and King's College London; Tien Y. Wong of Singapore National Eye Center and the National University of Singapore; Madeline H. Meier and Renate M. Houts of Duke University; Jie Ding of Singapore National Eye Center and Duke-NUS Graduate Medical School; Carol Y. Cheung and M. Kamran Ikram of Singapore National Eye Center, National University of Singapore, and Duke-NUS Graduate Medical School; and Richie Poulton of the University of Otago.
This research is supported by the National Institute on Aging (AG032282) and the United Kingdom Medical Research Council (MR/K00381X, G0601483). Additional support was provided by the National Institute of Child Health and Human Development (HD061298) and the Jacobs Foundation; M. H. M. was supported by the National Institute on Drug Abuse (P30 DA023026). The Dunedin Multidisciplinary Health and Development Research Unit is supported by the New Zealand Health Research Council.
For more information about this study, please contact: Idan Shalev at idan.shalev@duke.edu.
The APS journal Psychological Science is the highest ranked empirical journal in psychology. For a copy of the article "Retinal Vessel Caliber and Lifelong Neuropsychological Functioning : Retinal Imaging as an Investigative Tool for Cognitive Epidemiology?" and access to other Psychological Science research findings, please contact Anna Mikulak at 202-293-9300 or amikulak@psychologicalscience.org.
Blood vessels in the eye linked with IQ, cognitive function
2013-06-03
ELSE PRESS RELEASES FROM THIS DATE:
Europe needs to engage and invest in national R&D budgets
2013-06-03
In June's edition of Physics World Portugal's former science and technology minister, José Mariano Gago, calls for more investment in, and engagement with, national science budgets in light of the European Union's (EU) stagnated investment.
Gago also proposes a totally independent and credible "observatory" that would analyse national science policies and science budgets across Europe and give early warnings to scientists and the public on their developments.
The economic crisis has – at least since 2007 – divided research and development (R&D) within the EU. Large ...
Update on determination of death: Experts call for international consensus
2013-06-03
The criteria used to diagnose both circulatory and brain death in a patient are subject to variability and as such can be controversial. Anaesthesiologists play an important role in procedures related to the determination of death, so should have specific knowledge about medical, ethical and legal criteria of brain death definition. Experts will call for international consensus in a presentation at Euroanaesthesia 2013, the annual congress of the European Society of Anaesthesiology (ESA).
"Before the technological advances of the last century, death was diagnosed by ...
New method of mass-producing high-quality DNA molecules
2013-06-03
A new method of manufacturing short, single-stranded DNA molecules can solve many of the problems associated with current production methods. The new method, which is described in the scientific periodical Nature Methods, can be of value to both DNA nanotechnology and the development of drugs consisting of DNA fragments.
The novel technique for manufacturing short, single-stranded DNA molecules – or oligonucleotides – has been developed by researchers at Karolinska Institutet in Sweden and Harvard University. Such DNA fragments constitute a basic tool for researchers ...
Genome hints at markers for higher-producing, better-tasting chocolate
2013-06-03
The freshly sequenced genome of the most commonly cultivated cacao plant in the world is revealed in the open access journal Genome Biology this week. Researchers have utilised high quality DNA sequences to demonstrate the usefulness and quality of the sequence to identify genetic markers that can lead to higher yielding cocoa plants that still produce better tasting cocoa.
There are many varieties of the cacao tree (Theobroma cacao L.), but the green podded Costa Rican Matina or Amelonado variety is the most popular because of its high yield and pleasant flavor. In ...
Growth factor responsible for triggering hair follicle generation during wound healing identified
2013-06-03
PHILADELPHIA - Researchers in the Perelman School of Medicine at the University of Pennsylvania have determined the role of a key growth factor, found in skin cells of limited quantities in humans, which helps hair follicles form and regenerate during the wound healing process. When this growth factor, called Fgf9, was overexpressed in a mouse model, there was a two- to three-fold increase in the number of new hair follicles produced. Researchers believe that this growth factor could be used therapeutically for people with various hair and scalp disorders. The study appears ...
A step closer to artificial livers
2013-06-03
CAMBRIDGE, MA -- Prometheus, the mythological figure who stole fire from the gods, was punished for this theft by being bound to a rock. Each day, an eagle swept down and fed on his liver, which then grew back to be eaten again the next day.
Modern scientists know there is a grain of truth to the tale, says MIT engineer Sangeeta Bhatia: The liver can indeed regenerate itself if part of it is removed. However, researchers trying to exploit that ability in hopes of producing artificial liver tissue for transplantation have repeatedly been stymied: Mature liver cells, known ...
Printing innovations provide 10-fold improvement in organic electronics
2013-06-03
Menlo Park, Calif. — Through innovations to a printing process, researchers have made major improvements to organic electronics – a technology in demand for lightweight, low-cost solar cells, flexible electronic displays and tiny sensors. The printing method is fast and works with a variety of organic materials to produce semiconductors of strikingly higher quality than what has so far been achieved with similar methods.
Organic electronics have great promise for a variety of applications, but even the highest quality films available today fall short in how well they ...
Evidence mounts that 4 lifestyle changes will protect heart, reduce your risk of death
2013-06-03
A large, multi-center study led by Johns Hopkins researchers has found a significant link between lifestyle factors and heart health, adding even more evidence in support of regular exercise, eating a Mediterranean-style diet, keeping a normal weight and, most importantly, not smoking.
The researchers found that adopting those four lifestyle behaviors protected against coronary heart disease as well as the early buildup of calcium deposits in heart arteries, and reduced the chance of death from all causes by 80 percent over an eight-year period. Results of the study, ...
IU researchers focus on a brain protein and an antibiotic to block cocaine craving
2013-06-03
BLOOMINGTON, Ind. -- A new study conducted by a team of Indiana University neuroscientists demonstrates that GLT1, a protein that clears glutamate from the brain, plays a critical role in the craving for cocaine that develops after only several days of cocaine use.
The study, appearing in The Journal of Neuroscience, showed that when rats taking large doses of cocaine are withdrawn from the drug, the production of GLT1 in the nucleus accumbens, a region of the brain implicated in motivation, begins to decrease. But if the rats receive ceftriaxone, an antibiotic used ...
New Multi-Tool Invention, the Cole-Bar Hammer, Raises Goal of $100,000 in First 30 Days of Kickstarter Crowd-Funding Campaign
2013-06-03
A multifunction tool based on a combination hammer and crowbar has met its $100,000 Kickstarter goal with 30 days to spare. The crowd-funded campaign launched April 24 and ends June 24, 2013. "We are all amazed at the overwhelming positive response to the Cole-Bar and we are very excited about making the best tool that we can," said the Cole-Bar team's spokesperson, Brandon Hyde.
The Cole-Bar Hammer was inspired by its inventor's late son, Cole Hyde, who had the idea for the tool when he was just eleven years old. When Cole tragically passed away less than ...