Summary: Researchers say a new retinal imaging test could be a reliable tool for measuring the progression of neurodegenerative diseases, such as Alzheimer’s. The study reports the tool can detect drusen, which is often higher in those with AD.

Source: Queen’s University Belfast.

Researchers from Queen’s University Belfast have shown for the first time that the eye could be a surrogate for brain degeneration like Alzheimer’s disease (AD).

This research results have recently been published in the Journal of Ophthalmic Research and is the first clinical study showing a potential for peripheral retinal imaging to be used in monitoring AD and potentially other neurodegenerative diseases.

The team, led by Dr Imre Lengyel, Senior Lecturer and Researcher at the School of Medicine Dentistry and Biomedical Sciences at Queen’s University have found that by examining the eye we might be able to reflect on what might be taking place in the brain.

The work was carried out alongside health professionals and care providers for AD patients and explored whether there are manifestations of AD in the eye.

Based on laboratory observations the team hypothesized that changes in the peripheral retina could be important to explore the association between the eye and the brain.

Using ultra-wide field imaging technology developed by Optos Plc, the team found that there are indeed several changes that seems to be, especially in the peripheral retina, associated with this debilitating condition.

One of the changes in the eye that the study observed was a higher than normal appearance of drusen, the yellow ‘spots’ identifiable on retinal images, in people with AD.

Drusen are small deposits of fat, proteins and minerals, including calcium and phosphate deposits that form in a layer underneath the retina. These spots are a symptom of ageing and often seen in people over 40. A few of these deposits are harmless, but once they increase in number and size they contribute to the degeneration of the retina.

Dr Lengyel explains: “These exciting research results suggests that our original hypothesis was right and wide field eye imaging could indeed help monitoring disease progression in patients with AD.”

Another significant change observed in the study was measured in the peripheral retinal blood circulation in AD.

The research team found that people with AD have wider blood vessels close to the optic nerve, but these thin faster than in control subjects towards the retinal periphery. Both of these are likely to slow blood flow and impair nutrient and oxygen flow in the peripheral retina.

Dr Lengyel continues: “Eye imaging is quick, simple, well tolerated and costs a fraction to that of brain scans so there are tremendous benefits to both the professional and the patient.”

While peripheral retinal imaging is not a diagnostic measure for AD, the simple, quick and inexpensive monitoring of change in the eye could serve as a tool for disease progression in the brain.

Professor Craig Ritchie, Professor of the Psychiatry of Ageing at the University of Edinburgh is co-author on the study. He comments: “Changes in the eye are very easy to measure relative to other measures of brain health.

“Our research team, led by Queen’s University, was able to identify early markers in people many years before dementia develops. We have opened a window to identify high risk groups who may benefit from specific prevention advice.”

To extend these observations, the research team is currently involved in several further dementia related studies. They will be examining and following patients with very early stage AD through the Deep and Frequent Phenotyping study, the world’s most in depth study to detect early signs of Alzheimer’s disease progression conducted in the UK.

Funding: Research in Dr Lengyel’s laboratory is supported by the Medical Research Council, Economic and Social Research Council, National Institute for Health Research, and Northern Ireland Clinical Research Facility as well industrial partners Optos Plc.

Source: Sian Devlin – Queen’s University Belfast 
Publisher: Organized by NeuroscienceNews.com.
Image Source: NeuroscienceNews.com image is in the public domain.
Original Research: Open access research for “Peripheral Retinal Imaging Biomarkers for Alzheimer’s Disease: A Pilot Study” by Lajos Csincsik, Thomas J. MacGillivray, Erin Flynn, Enrico Pellegrini, Giorgos Papanastasiou, Neda Barzegar-Befroei, Adrienne Csutak, Alan C. Bird, Craig W. Ritchie, Tunde Peto, and Imre Lengyel in Journal of Ophthalmic Research. Published April 5 2018.
doi:10.1159/000487053

Abstract

Peripheral Retinal Imaging Biomarkers for Alzheimer’s Disease: A Pilot Study

Purpose: To examine whether ultra-widefield (UWF) retinal imaging can identify biomarkers for Alzheimer’s disease (AD) and its progression.

Methods: Images were taken using a UWF scanning laser ophthalmoscope (Optos P200C AF) to determine phenotypic variations in 59 patients with AD and 48 healthy controls at baseline (BL). All living participants were invited for a follow-up (FU) after 2 years and imaged again (if still able to participate). All participants had blood taken for genotyping at BL. Images were graded for the prevalence of age-related macular degeneration-like pathologies and retinal vascular parameters. Comparison between AD patients and controls was made using the Student t test and the χ2 test.

Results: Analysis at BL revealed a significantly higher prevalence of a hard drusen phenotype in the periphery of AD patients (14/55; 25.4%) compared to controls (2/48; 4.2%) [χ2 = 9.9, df = 4, p = 0.04]. A markedly increased drusen number was observed at the 2-year FU in patients with AD compared to controls. There was a significant increase in venular width gradient at BL (zone C: 8.425 × 10–3 ± 2.865 × 10–3 vs. 6.375 × 10–3 ± 1.532 × 10–3, p = 0.008; entire image: 8.235 × 10–3 ± 2.839 × 10–3 vs. 6.050 × 10–3 ± 1.414 × 10–3, p = 0.004) and a significant decrease in arterial fractal dimension in AD at BL (entire image: 1.250 ± 0.086 vs. 1.304 ± 0.089, p = 0.049) with a trend for both at FU.

Conclusions: UWF retinal imaging revealed a significant association between AD and peripheral hard drusen formation and changes to the vasculature beyond the posterior pole, at BL and after clinical progression over 2 years, suggesting that monitoring pathological changes in the peripheral retina might become a valuable tool in AD monitoring.

Summary: A new study reports children who receive musical training have better word discrimination than other kindergarteners who had not undertaken music lessons.

Source: MIT.

Many studies have shown that musical training can enhance language skills. However, it was unknown whether music lessons improve general cognitive ability, leading to better language proficiency, or if the effect of music is more specific to language processing.

A new study from MIT has found that piano lessons have a very specific effect on kindergartners’ ability to distinguish different pitches, which translates into an improvement in discriminating between spoken words. However, the piano lessons did not appear to confer any benefit for overall cognitive ability, as measured by IQ, attention span, and working memory.

“The children didn’t differ in the more broad cognitive measures, but they did show some improvements in word discrimination, particularly for consonants. The piano group showed the best improvement there,” says Robert Desimone, director of MIT’s McGovern Institute for Brain Research and the senior author of the paper.

The study, performed in Beijing, suggests that musical training is at least as beneficial in improving language skills, and possibly more beneficial, than offering children extra reading lessons. The school where the study was performed has continued to offer piano lessons to students, and the researchers hope their findings could encourage other schools to keep or enhance their music offerings.

Yun Nan, an associate professor at Beijing Normal University, is the lead author of the study, which appears in the Proceedings of the National Academy of Sciences the week of June 25.

Other authors include Li Liu, Hua Shu, and Qi Dong, all of Beijing Normal University; Eveline Geiser, a former MIT research scientist; Chen-Chen Gong, an MIT research associate; and John Gabrieli, the Grover M. Hermann Professor in Health Sciences and Technology, a professor of brain and cognitive sciences, and a member of MIT’s McGovern Institute for Brain Research.

Benefits of music

Previous studies have shown that on average, musicians perform better than nonmusicians on tasks such as reading comprehension, distinguishing speech from background noise, and rapid auditory processing. However, most of these studies have been done by asking people about their past musical training. The MIT researchers wanted to perform a more controlled study in which they could randomly assign children to receive music lessons or not, and then measure the effects.

They decided to perform the study at a school in Beijing, along with researchers from the IDG/McGovern Institute at Beijing Normal University, in part because education officials there were interested in studying the value of music education versus additional reading instruction.

“If children who received music training did as well or better than children who received additional academic instruction, that could a justification for why schools might want to continue to fund music,” Desimone says.

The 74 children participating in the study were divided into three groups: one that received 45-minute piano lessons three times a week; one that received extra reading instruction for the same period of time; and one that received neither intervention. All children were 4 or 5 years old and spoke Mandarin as their native language.

After six months, the researchers tested the children on their ability to discriminate words based on differences in vowels, consonants, or tone (many Mandarin words differ only in tone). Better word discrimination usually corresponds with better phonological awareness — the awareness of the sound structure of words, which is a key component of learning to read.

Children who had piano lessons showed a significant advantage over children in the extra reading group in discriminating between words that differ by one consonant. Children in both the piano group and extra reading group performed better than children who received neither intervention when it came to discriminating words based on vowel differences.

The researchers also used electroencephalography (EEG) to measure brain activity and found that children in the piano group had stronger responses than the other children when they listened to a series of tones of different pitch. This suggest that a greater sensitivity to pitch differences is what helped the children who took piano lessons to better distinguish different words, Desimone says.

“That’s a big thing for kids in learning language: being able to hear the differences between words,” he says. “They really did benefit from that.”

In tests of IQ, attention, and working memory, the researchers did not find any significant differences among the three groups of children, suggesting that the piano lessons did not confer any improvement on overall cognitive function.

Aniruddh Patel, a professor of psychology at Tufts University, says the findings also address the important question of whether purely instrumental musical training can enhance speech processing.

“This study answers the question in the affirmative, with an elegant design that directly compares the effect of music and language instruction on young children. The work specifically relates behavioral improvements in speech perception to the neural impact of musical training, which has both theoretical and real-world significance,” says Patel, who was not involved in the research.

Educational payoff

Desimone says he hopes the findings will help to convince education officials who are considering abandoning music classes in schools not to do so.

“There are positive benefits to piano education in young kids, and it looks like for recognizing differences between sounds including speech sounds, it’s better than extra reading. That means schools could invest in music and there will be generalization to speech sounds,” Desimone says. “It’s not worse than giving extra reading to the kids, which is probably what many schools are tempted to do — get rid of the arts education and just have more reading.”

Desimone now hopes to delve further into the neurological changes caused by music training. One way to do that is to perform EEG tests before and after a single intense music lesson to see how the brain’s activity has been altered.

Funding: The research was funded by the National Natural Science Foundation of China, the Beijing Municipal Science and Technology Commission, the Interdiscipline Research Funds of Beijing Normal University, and the Fundamental Research Funds for the Central Universities

Source: Anne Trafton – MIT
Publisher: Organized by NeuroscienceNews.com.
Image Source: NeuroscienceNews.com image is adapted from the MIT news release.
Original Research: Abstract for “Piano training enhances the neural processing of pitch and improves speech perception in Mandarin-speaking children” by Yun Nan, Li Liu, Eveline Geiser, Hua Shu, Chen Chen Gong, Qi Dong, John D. E. Gabrieli, and Robert Desimone in PNAS. Published June 25 2018.
doi:10.1073/pnas.1808412115

Abstract

Piano training enhances the neural processing of pitch and improves speech perception in Mandarin-speaking children

Musical training confers advantages in speech-sound processing, which could play an important role in early childhood education. To understand the mechanisms of this effect, we used event-related potential and behavioral measures in a longitudinal design. Seventy-four Mandarin-speaking children aged 4–5 y old were pseudorandomly assigned to piano training, reading training, or a no-contact control group. Six months of piano training improved behavioral auditory word discrimination in general as well as word discrimination based on vowels compared with the controls. The reading group yielded similar trends. However, the piano group demonstrated unique advantages over the reading and control groups in consonant-based word discrimination and in enhanced positive mismatch responses (pMMRs) to lexical tone and musical pitch changes. The improved word discrimination based on consonants correlated with the enhancements in musical pitch pMMRs among the children in the piano group. In contrast, all three groups improved equally on general cognitive measures, including tests of IQ, working memory, and attention. The results suggest strengthened common sound processing across domains as an important mechanism underlying the benefits of musical training on language processing. In addition, although we failed to find far-transfer effects of musical training to general cognition, the near-transfer effects to speech perception establish the potential for musical training to help children improve their language skills. Piano training was not inferior to reading training on direct tests of language function, and it even seemed superior to reading training in enhancing consonant discrimination.

Summary: Researchers report developmental prosopagnosia, or face blindness, occurs as the results of neurobiological problems that broadly affect visual recognition.

Source: Dartmouth College.

Imagine that you’re supposed to meet colleagues for dinner, only you can’t remember what their faces look like. For some, this is a reality, as people with face blindness or developmental prosopagnosia (DP) have severe difficulties recognizing faces, including those of family and friends, despite having no history of brain damage (e.g., brain trauma, head injuries). A Dartmouth study finds that developmental prosopagnosia often occurs as a result of a neurobiological problem in the brain, which affects visual recognition broadly. The findings are published in the Proceedings of the National Academy of Sciences.

“Our results indicate that neural abnormalities in many people with DP are more widespread than previous studies have suggested,” says senior author Bradley Duchaine , a professor of psychological and brain sciences and the principal investigator of the Social Perception Lab at Dartmouth College. Duchaine worked closely with Guo Jiahui, a Dartmouth psychological and brain sciences graduate student and member of his lab, who served as first author of the study.

For the research, the Dartmouth team used functional MRI to measure the brain responses to video clips showing faces, objects, scrambled objects, scenes, and bodies. They then compared these responses in 22 people with developmental prosopagnosia and 25 control participants to determine which regions in the facial processing system may be abnormal and whether any regions that respond preferentially to scenes, bodies, or objects respond abnormally in the developmental prosopagnosics.

This is the first study of DP to use videos of moving faces and is more in line with how one experiences the world, rather than relying on static images of faces. It is also the first fMRI study of its kind to investigate activity in scene and body areas.

The researchers examined 12 face-selective areas throughout the brain (six face-selective areas in each hemisphere). These are different parts of the brain that are interconnected and form the face processing network. The findings showed that DPs had reduced responses to faces but normal responses to objects, scenes, and bodies across all 12 of the face-selective areas.

The study also looked at how DPs responded to visual categories, such as scene areas, body areas and object areas. Known as category-selective areas, the researchers assessed how strongly tuned a cortical area is to a particular category; if the cortex doesn’t develop properly, behavioral deficits ensue. In comparison to the controls, the DPs had pronounced reductions in their responses to scenes and marginal reductions in their responses to bodies. Yet, DPs’ responses to objects in object areas were normal and the same as that of the controls.

“The study participants with developmental prosopagnosia had reduced responses to not only face areas but also to scene areas and body areas. Our findings suggest that most cases of developmental prosopagnosia are not caused by a lack of experience with faces during development but instead, by a broader neurobiological cause that affects all three types of areas,” explained Duchaine. “Our results indicate that the deficits across face areas, scene areas and body areas may be due to a broad region of cortex that did not develop properly. In other words, these areas did not get wired properly during development,” he added.

Past research on visual recognition disorders has focused almost entirely on prosopagnosia; however, the results indicate that many DPs have deficits that extend beyond face areas and it seems likely that abnormalities in scene and body areas will cause difficulties with scene and body perception. Duchaine plans to conduct further research to gain insight into these other visual recognition deficits in order to better understand the types of disorders that impact the visual system.

Duchaine has been conducting research on face perception and face blindness for over 20 years. The findings build on his earlier work, which found abnormalities in some face-selective areas but which did not investigate the entire face network or areas that are selective for other categories such as scenes and bodies.

Source: Amy D. Olson – Dartmouth College
Publisher: Organized by NeuroscienceNews.com.
Image Source: NeuroscienceNews.com image is credited to Guo Jiahui.
Original Research: Abstract for “Developmental prosopagnosics have widespread selectivity reductions across category-selective visual cortex” by Guo Jiahui, Hua Yang, and Bradley Duchaine in PNAS. Published June 25 2018.
doi:10.1073/pnas.1802246115

Abstract

Developmental prosopagnosics have widespread selectivity reductions across category-selective visual cortex

Developmental prosopagnosia (DP) is a neurodevelopmental disorder characterized by severe deficits with facial identity recognition. It is unclear which cortical areas contribute to face processing deficits in DP, and no previous studies have investigated whether other category-selective areas function normally in DP. To address these issues, we scanned 22 DPs and 27 controls using a dynamic localizer consisting of video clips of faces, scenes, bodies, objects, and scrambled objects. We then analyzed category selectivity, a measure of the tuning of a cortical area to a particular visual category. DPs exhibited reduced face selectivity in all 12 face areas, and the reductions were significant in three posterior and two anterior areas. DPs and controls showed similar responses to faces in other category-selective areas, which suggests the DPs’ behavioral deficits with faces result from problems restricted to the face network. DPs also had pronounced scene-selectivity reductions in four of six scene-selective areas and marginal body-selectivity reductions in two of four body-selective areas. Our results demonstrate that DPs have widespread deficits throughout the face network, and they are inconsistent with a leading account of DP which proposes that posterior face-selective areas are normal in DP. The selectivity reductions in other category-selective areas indicate many DPs have deficits spread across high-level visual cortex.