Hearing is often described as a simple act of receiving sound, but in reality it’s a deeply interactive process. Every noise, voice, or melody you encounter sets off an intricate exchange between your ears and your brain. Your brain sorts through the chaos, interprets patterns, and gives meaning to what you hear. When hearing weakens, this seamless coordination becomes strained, and the brain must work harder to keep up.
When sound input becomes faint or distorted, the brain starts compensating by trying to reconstruct what was missed. That extra mental effort drains cognitive resources that would normally support attention, memory, and comprehension. People may not notice the load they’re carrying until they begin feeling mentally tired, overwhelmed in conversation, or unable to follow speech in groups.
Hearing loss also affects the brain’s auditory centers—the areas responsible for interpreting sound and supporting higher-level thinking skills. When these pathways receive less stimulation, they can weaken, which may influence broader cognitive functions over time. This connection helps explain why untreated hearing difficulties often coincide with challenges in focus, processing, or recall.
Social behavior plays a role as well. When hearing becomes a struggle, many individuals gradually step back from group interactions or noisy environments. With fewer conversations and less meaningful auditory engagement, the brain loses important practice. This creates a circular pattern: difficulty hearing leads to less participation, which then reduces the brain’s exposure to the very stimulation that keeps it sharp.
Dr. Ådén[/caption]
Ulrika Ådén PhD
Professor of Neonatology
Department of Women's and
Children's Health Karolinska
MedicalResearch.com: What is the background for this study?
Response: Children born preterm are at higher risk of cognitive impairment during childhood and later in life. However, an important unresolved question is whether these impairments primarily reflect genetic susceptibility or are driven by the biological consequences of being born too early. Cognitive development is known to have a strong heritable component (~70 %), and previous studies have attempted to disentangle genetic and environmental contributions, for example through sibling comparison designs. Although informative, such approaches have inherent limitations.
In this study, we aimed to investigate long-term cognitive outcomes across a range of gestational age groups including very preterm, moderately preterm, late preterm, and early term, compared to children born full term. Importantly, we accounted for genetic influences as well as a range of potential confounding factors, including prenatal risks and child-specific factors. This approach provides a more nuanced understanding of the extent to which cognitive outcomes associated with preterm birth reflect biological versus inherited risk.
Dr. Harmer[/caption]
Peter A. Harmer, PhD, MPH, AT-Ret, FACSM
Senior Associate Research Scientist
Oregon Research Institute
MedicalResearch.com: What is the background for this study?
Response: Decline in various aspects of cognitive function, such as memory, executive function, and multitasking ability is common as we age. The rate and extent of decline varies among older adults but approximately 20% of those aged 65+ will experience clinically relevant mild cognitive impairment, which places them at increased risk of progressing to Alzheimer’s disease or related dementias. It is also associated with decreased mobility, increased risk of falls and impaired capacity for complex activities of daily living.
Lotfi Khemiri
Centre for Psychiatry Research
Stockholm, Sweden
MedicalResearch.com: What is the background for this study?
Response: Our study used large-scale national register data in close to 2 million children, and found that parental abuse of both alcohol and drugs are associated with increased risk of intellectual disability in the offspring. Importantly, the risk increase was observed in both mothers and fathers which to the best of our knowledge is a novel finding, and may be explained by both genetic and environmental factors including toxic effects of substance intake on fetal development.
Prof. Leon[/caption]
Michael Leon, Professor emeritus
Dr. Stern[/caption]
Robert A. Stern, Ph.D.
Professor of Neurology, Neurosurgery, and Anatomy & Neurobiology
Director of Clinical Research, BU CTE Center
Senior Investigator, BU Alzheimer’s Disease Research Center
Boston University School of Medicine
MedicalResearch.com: What is the background for this study?
Response: The link between playing American football at the professional level and later-life brain disorders like chronic traumatic encephalopathy – or CTE -- and ALS has received increasing attention over the past 15 years. Previous research has shown that former NFL players are more likely to die from CTE and amyotrophic lateral sclerosis (ALS) and more likely to report cognitive impairment, behavioral changes, and dementia during life. Despite previous research focusing on the later-life effects of playing American football at the professional level, the long-term effects of college football participation remain largely unknown.
We had two goals for this new investigation. The first was to conduct a survey of the current overall health status, including cognitive and other neurological disorders, of older former college American football players compared with men in the general population. The second goal was to examine the mortality rate and causes of death in a cohort of older former college football players. The target population for this study was all 447 former Notre Dame football players who were listed as seniors on the varsity rosters during the 1964-1980 seasons. This was the era of legendary coaches Ara Parseghian and Dan Devine. I should add that this study was fully independent of the University of Notre Dame.
Dr. Launer[/caption]
Lenore J. Launer, Ph.D.
Chief, Laboratory of Epidemiology and Population Sciences
Intramural Research Program, National Institute on Aging.
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Identifying early risk factors and early changes in the brain will have a major impact on future clinical and public health priorities related to the looming epidemic of dementia. Several studies based on older populations suggest mid-life is an important period to start prevention measures. To date control of blood pressure levels has been the most robust and promising candidate to target for prevention of future cognitive impairment. Although several studies have looked at levels of blood pressure and risk for cognitive impairment, it was not known whether trajectories from young adulthood to middle age studies provided additional information about risk. To investigate possible biomarkers of future risk, we chose to examine the association of the mean arterial blood pressure trajectories to indicators of pathology seen on MRI and that are associated with cognition.
We highlight the results of the mean arterial blood pressure (MAP) measure, which is an integrated measure of systolic and diastolic blood pressure.
Dr. Shiou Liang[/caption]
Wee Shiou Liang, PhD
Associate Professor | Health and Social Sciences, Singapore Institute of Technology
Faculty | Geriatric Education and Research Institute
Singapore
MedicalResearch.com: What is the background for this study?
Response: This study was funded by Singapore’s Ministry of Health Geriatric Education and Research Institute.
We randomly recruited 500+ adults aged 21-90+ from the residential town of Yishun. We performed detailed assessments of physical and cognitive performance, body composition using DEXA, and participants also provided information on their levels and frequencies of physical activities (PA) including recreational PA/exercise, commuting, housework and other occupational related PA. The demographics of the sample of participants is the same as that of Singapore in terms of age and ethnic composition. Comparing the results of those aged 21-<65 and those >=65 years, only around a third (36%; 90) of those in the younger group and only around half (48%;116) of those in the older age group, met guidelines recommended physical activity quota exclusively from recreational PA/exercise. But nearly two thirds (61% younger; 152 and 66% older; 159) met this target exclusively through housework.
Dr. Nation[/caption]
Daniel A. Nation, Ph.D.,
Associate Professor of Psychological Science
Institute for Memory Impairments and Neurological Disorders
University of California, Irvin
MedicalResearch.com: What is the background for this study?
Response: Hypertension is a risk factor for cognitive decline and dementia, and treatment of hypertension has been linked to decreased risk for cognitive impairment.
Prior studies have attempted to identify which specific type of antihypertensive treatment conveys the most benefit for cognition, but findings have been mixed regarding this question. We hypothesized that antihypertensive drugs acting on the brain angiotensin system may convey the greatest benefit since they affect the brain angiotensin system that has been implicated in memory function.
Dr. Dunietz[/caption]
Galit Levi Dunietz MPH, PhD
Assistant Professor
Dr. Braley[/caption]
Dr. Willette[/caption]
Auriel Willette, PhD
Assistant Professor
Food Science and Human Nutrition
Iowa State University
MedicalResearch.com: What is the background for this study?
Response: To date, pharmacology therapies done to slow down or halt Alzheimer's disease have been inconclusive. Lifestyle interventions like changes in diet and activity are also mixed but do show some promise. Dietary clinical trials or self-reported diet have tended to focus on groups of foods such as the Mediterranean or MIND diet. To build from this excellent work, we were curious if we could pinpoint specific foods that were correlated with changes in fluid intelligence over time. Fluid intelligence represents our ability to creatively use existing knowledge, working memory, and other components of "thinking flexibly."
Further, we tested if these patterns of association differed based on genetic risk. In this case, genetic risk was defined as having a family history of Alzheimer's disease or having 1-2 "bad" copies of the Apolipoprotein E (APOE) gene, which is the strongest genetic risk factor for Alzheimer's disease.
Dr. Rosi[/caption]
Susanna Rosi, Ph.D.
Lewis and Ruth Cozen Chair II
Dr. Mahncke[/caption]
MedicalResearch.com: What is heart failure?
Response: Heart failure – sometimes called congestive heart failure or congestive cardiac failure – is when the heart cannot pump sufficient blood flow to maintain the body’s needs. Common symptoms include excessive tiredness, shortness of breath and swelling particularly in legs. It’s treated with a combination of lifestyle changes, drugs, and devices. An estimated 6.5 million Americans are diagnosed with heart failure, with 960,000 new cases each year, leading some to describe it as reaching epidemic proportions. In older adults, it’s the most common cause of hospital readmissions within 30 days of discharge and among the most costly areas of Medicare expenditures.