MedicalResearch.com Interview with:Roi LevyThe Leslie and Susan Gonda (Goldschmied) Multidisciplinary Brain Research Center,
The Mina and Everard Goodman Faculty of Life Sciences
Bar Ilan University
Ramat Gan, Israel
MedicalResearch.com: What is the background for this study?Response: Long-term memory after an experience takes many hours to be reach its final form. During the consolidation period, the nascent memory is labile: the consolidation can be interrupted by new experiences, or new experiences that are too insignificant to be remembered can capture the consolidation process, and thereby be remembered.
To avoid potentially maladaptive interactions between a new experience and consolidation, a major portion of the consolidation is deferred to the time in which we sleep, when new experiences are unlikely. For over 100 years, studies have demonstrated that sleep improves memory formation. More recent studies have shown that consolidation occurs during sleep, and that consolidation depends on the synthesis of products that support memory formation. Consolidation is unlikely to be shut off immediately when we are awakened from sleep. At this time, even a transient experience could capture the consolidation, leading to a long-lasting memory of an event that should not be remembered, or could interfere with the consolidation. We have identified a mechanism that prevents long-term memories from being formed by experiences that occur when awakened from sleep.
(more…)
MedicalResearch.com Interview with:Steven J. Hardy, PhdLicensed Clinical Psychologist
Divisions of Hematology and Oncology
Children’s National Health System
Assistant Professor of Pediatrics and Psychiatry & Behavioral Sciences
George Washington School of Medicine and Health Sciences Washington, DC
MedicalResearch.com: What is the background for this study? What are the main findings?Response: Children with sickle cell disease exhibit neurocognitive deficits as a consequence of either silent or overt cerebral infarction or disease-related non-infarct central nervous system effects (likely resulting from chronic anemia and hypoxic events). These complications often lead to impairment in executive functioning (e.g., working memory, attention, inhibition, cognitive flexibility), which can make it difficult to focus in class, plan for long-term school projects, remember and carry out multi-step tasks or assignments, and stay organized. The literature on interventions to reduce neurocognitive sequelae of sickle cell disease is extremely limited.
Our research team investigated a promising home-based, computerized cognitive training program (Cogmed) involving repeated practice on performance-adapted exercises targeting working memory with a sample of youth (ages 7 – 16) with sickle cell disease. Of the participants who have enrolled in the study (n = 70), 49% exhibited working memory deficits (<25% in the general population have a working memory deficit) and were randomized to an eight-week waitlist or to begin Cogmed immediately. Participants who used Cogmed demonstrated significant improvements on multiple measures of working memory, while those randomized to the waitlist group only exhibited such improvements after receiving Cogmed. Approximately 25% of participants completed the recommended number of Cogmed sessions (20 – 25 sessions). However, analyses revealed that participants who completed at least 10 sessions (about 50% of the participants) showed comparable levels of working memory improvement.
(more…)
MedicalResearch.com Interview with:
Jill M. Goldstein, Ph.D.
Director of Research for the Connors Center for Women's Health and Gender Biology
Brigham and Women's Hospital and
Professor of Psychiatry and Medicine at Harvard Medical School
MedicalResearch.com: What is the background for this study? Response: Maintaining intact memory function as we age is one of the primary public health challenges of our time. In fact, women are at almost twice the risk for Alzheimer's disease and it is not only because women live longer. Thus, it is incumbent upon us to understand this sex difference and incorporate the knowledge into the development of sex-dependent therapeutics.
Our study focused on beginning this investigation by understanding how memory circuitry and memory function change over the menopausal transition, when we believe that sex differences in memory aging emerge. By understanding healthy aging, we will better understand how the brain goes awry with age differently in men and women and who might be at highest risk for Alzheimer's disease later in life.
(more…)
MedicalResearch.com Interview with:
Ursala. H. Winzer-Serhan Ph.D.
Associate Professor
Department of Neuroscience and Experimental Therapeutics
Texas A&M Health Science Center
MedicalResearch.com: What is the background for this study? What are the main findings?Response: Nicotine is a plant alkaloid that is naturally occurring in the tobacco plant. Smoking delivers nicotine to the brain where it acts as a stimulant. Tobacco and electronic cigarette smoking delivers many other chemicals to the body, which are harmful and can cause cancer.
However, the drug nicotine by itself is relatively benign and poses few health risks for most people. Nicotine acts in the brain on nicotinic receptors, which are ion channels that are widely expressed in the brain. They play an important role in cognitive functions. Research with rodents and in humans has shown that nicotine can enhance learning and memory, and furthermore, can protect neurons during injuries and in the aging brain. With the increasingly older population, it becomes more and more important to delay cognitive decline in the elderly. Right now, there is no drug available that could delay aging of the brain.
(more…)
MedicalResearch.com Interview with:Ron L. Davis, PhD Professor and Chair
Department of Neuroscience
Florida campus of The Scripps Research Institute
MedicalResearch.com: What is the background for this study? What are the main findings?Response: While calcium’s importance for our bones and teeth is well known, its role in neurons—in particular, its effects on processes such as learning and memory—has been less well defined. Our new study, published in the journal Cell Reports, offers new insights how calcium in mitochondria—the powerhouse of all cells—can impact the development of the brain and adult cognition.
Specifically, we show in fruit flies, a widely used model system, that blocking a channel that brings calcium to the mitochondria called “mitochondrial calcium uniporter” causes memory impairment but does not alter learning capacity. That surprised us – we thought they wouldn’t be able to learn at all. This is important because defects in the same calcium channel function have been shown to be associated with intellectual disability in humans.
(more…)
MedicalResearch.com Interview with:
Ron L. Davis, PhD Professor and Chair
Department of Neuroscience
Florida campus of The Scripps Research Institute
MedicalResearch.com: What is the background for this study? What are the main findings?Response: While calcium’s importance for our bones and teeth is well known, its role in neurons—in particular, its effects on processes such as learning and memory—has been less well defined. Our new study, published in the journal Cell Reports, offers new insights how calcium in mitochondria—the powerhouse of all cells—can impact the development of the brain and adult cognition.
Specifically, we show in fruit flies, a widely used model system, that blocking a channel that brings calcium to the mitochondria called “mitochondrial calcium uniporter” causes memory impairment but does not alter learning capacity. That surprised us – we thought they wouldn’t be able to learn at all. This is important because defects in the same calcium channel function have been shown to be associated with intellectual disability in humans.
(more…)
MedicalResearch.com Interview with:Flavio Frohlich PhD
Assistant Professor
Departments of Psychiatry, Cell Biology and Physiology, Biomedical Engineering, and Neurology
Neuroscience Center School of Medicine
University of North Carolina at Chapel Hill
MedicalResearch.com: What is the background for this study?Response: Although we do not understand why we sleep, it is clear that sleep is very important for overall well being and health. One of many likely functions of sleep is memory consolidation, the process of stabilizing previously acquired memories. In particular, a brief electric brain activity pattern called the sleep spindle has been shown to correlate with memory consolidation and learning in general. We asked if this brain rhythm causes memory consolidation by using non-invasive feedback brain stimulation to selectively enhance sleep spindles. We applied a weak electric current in the shape of a sleep spindle to the scalp each time our algorithm detected a sleep spindle in the EEG.
(more…)
MedicalResearch.com Interview with:Jeff Boissoneault, PhD
Research Assistant Professor
Center for Pain Research and Behavioral Health
Department of Clinical and Health Psychology
University of Florida
MedicalResearch.com: What is the background for this study? What are the main findings?Response: Many older adults are regular moderate drinkers. Although moderate drinking is considered to be a low risk behavior, growing evidence suggests older adults may be more susceptible to the cognitive and behavioral effects of moderate alcohol intake than younger people. We have previously shown that blood alcohol concentrations (BACs) below the legal limit for driving in the United States, 0.08 g/dL, affect working, or short-term, memory performance in older but not younger adults. For this study, we examined frontal theta power (FTP) and posterior alpha power (PAP), which are electrophysiological measures of brain activity associated with cognitive effort and maintenance of visual information, during a working memory task in both older and younger social drinkers.
We found that during a nine-second delay period during which participants held briefly-displayed images in memory, moderate alcohol intake increased PAP in younger adults but decreased PAP in older adults. Examining the relationship between PAP and behavioral performance (accuracy and reaction time) suggested older adults may attempt to compensate for moderate alcohol-induced working memory impairment by prioritizing quick responding over the protection of their mental representation of the task images from environmental distractions. Younger adults did not show this effect.
(more…)
MedicalResearch.com Interview with:Timothy Q. Duong, Ph.D
Stanley I. Glickman MD Professor of Ophthalmology, Radiology, and Physiology
South Texas Veterans Health Care System, VA Southwest National Primate Research Center
University of Texas Health Science Center
San Antonio, Texas
MedicalResearch.com: What is the background for this study? What are the main findings?Response: A single oral dose of methylene blue increased fMRI response in the bilateral insular cortex during a task that measured reaction time to a visual stimulus. The fMRI results also showed an increased response during short-term memory tasks involving the brain’s prefrontal cortex, which controls processing of memories. Methylene blue was also associated with a 7 percent increase in correct responses during memory retrieval. The findings suggest that methylene blue can regulate certain brain networks related to sustained attention and short-term memory after a single oral low dose.
(more…)
MedicalResearch.com Interview with:
Dr. Graham Murray PhD
University Lecturer
Department of Psychiatry
Addenbrooke's Hospital
Cambridge UK
Medical Research: What is the background for this study? What are the main findings?
Dr. Murray: There is debate about the extent to which ADHD persists into adulthood, with estimates suggesting that between 10-50% of children still have ADHD in adulthood. Diagnosis (whether in childhood or adulthood) is currently reliant on meeting symptom checklists (such as the American Psychiatric Association’s Diagnostic and Statistical Manual), and a current diagnosis is often the prerequisite to access health care from psychiatric services. We decided to follow up a sample of 49 teens who all had a confirmed diagnosis of ADHD at age 16. We also followed a control group made up of comparison healthy volunteers from the same social, ethnic and geographical background.
When we used the symptom checklist criteria of persistence, only 10% of patients still met ADHD diagnostic criteria in adulthood. However, there is more to ADHD than this. When it comes to adult brain structure and function, it didn’t make any difference whether symptom checklists were still met or not. On reaching adulthood, the adolescent ADHD group show reduced brain volume in the caudate nucleus - a key brain region that supports a host of cognitive functions, including working memory function. When we assessed working memory ability, we noted persistent problems in the adolescent ADHD group, with a third of the adolescent ADHD sample failing the memory test. The poor memory scores seemed to relate to a lack of responsiveness in the activity of the caudate nucleus that we could detect using functional MRI scans. In the control group, when the memory questions became more difficult, the caudate nucleus became more active, and this appeared to help the control group perform well; in the adolescent ADHD group, the caudate nucleus kept the same level of activity throughout the test. It was as if, for the controls, when the test got harder, the caudate nucleus went up a gear in its activity, and this is likely to have helped solve the memory problems. But for the adolescence ADHD group, the caudate couldn’t go up a gear when the test became harder, and this likely resulted in poorer performance.(more…)
MedicalResearch.com Interview with:
Laura Steenbergen, MSc., PhD Candidate
Cognitive Psychology at Institute of Psychology
Leiden UniversityMedical Research: What is the background for this study? What are the main findings?
Response: A recent initiative supported by several eminent research institutes and scientists calls for a more critical and active role of the scientific community in evaluating the sometimes far-reaching, sweeping claims from the brain training industry with regard to the impact of their products on cognitive performance. tDCS is a noninvasive brain stimulation technique that has developed into a promising tool to boost human cognition. Previous studies using medical tDCS devices have shown that tDCS promotes working memory (WM) updating in healthy individuals and patients. The aim of the current study was to investigate whether the commercial tDCS headset foc.us (v.1), which is easily and freely available to anyone in the world,does in fact improve cognitive performance, as advertised in the media. Results showed that active stimulation with the commercial device, compared to sham stimulation, significantly decreased working memory performance. The device we testedis just one example of a commercial device that can easily be purchased and, without any control or expert knowledge, used by anyone. The results of our study are straightforward in showing that the claims made by companies manufacturing such devices need to be validated. Even if the consequences of long-term or frequent use of the device are yet to be demonstrated, our findings provide strong support the important role of the scientific community in validating and testing far reaching claims made by the brain training industry.
(more…)
MedicalResearch.com Interview with:
Auriel A. Willette, M.S., Ph.D.
Food Science and Human Nutrition
Neuroscience Interdepartmental Graduate Program
Gerontology Interdepartmental Graduate Program
Iowa State University, Ames
Medical Research: What is the background for this study? What are the main findings?Response: Obesity is a major health concern around the world. Obesity causes insulin resistance, defined in this case as the inability of insulin to bind to its receptor and mediate glucose metabolism. Other researchers and I have recently found that higher insulin resistance is associated with less glucose metabolism in the brains of patients with Alzheimer's disease. This relationship is found primarily in medial temporal lobe, an area necessary for generating new memories of facts and events. This is important because Alzheimer's disease is characterized by progressive decreases in glucose metabolism over time, and partly drives worse memory performance. Insulin resistance in midlife also increases the risk of developing Alzheimer's disease.
We wanted to determine if insulin resistance is linked to similar effects in cognitively normal, late middle-aged participants decades before Alzheimer's disease typically occurs. If so, insulin resistance might be an important biological marker to track from middle-age onwards. Thus, we examined the association between insulin resistance, regional glucose metabolism using FDG-PET, and memory function in 150 middle-aged participants, many of whom had a mother or father with Alzheimer's disease.
We found that higher insulin resistance was strongly associated with less glucose metabolism throughout many brain regions, predominantly in areas that are affected by Alzheimer's disease. The strongest statistical effects were found in left medial temporal lobe, which again is important for generating new memories. This relationship, in turn, predicted worse memory performance, both immediately after learning a list of words and a 20-minute delay thereafter.
The take-home message is that insulin resistance has an Alzheimer's-like association with glucose metabolism in middle-aged, cognitively normal people at risk for Alzheimer's, an association which is related to worse memory.
(more…)
MedicalResearch.com Interview with: Dr. Lim Lee Wei
School of Biological Sciences, Nanyang Technological University, Singapore;
Department of Biological Sciences, Sunway University, MalaysiaMedical Research: What is the background for this study? What are the main findings?
Response: To date, pharmacological treatments for dementia have limited effects (most of the drugs failed in the second or third clinical trials) and there are no known treatments that cure or delay the progression of this memory impairment. Therefore, a novel non-pharmacological approach such as deep brain stimulation (DBS) is currently considered as an alternative treatment to reduce the symptomatic and progression of this memory deterioration.
Deep brain stimulation for dementia-related disease is currently evaluated as a potential therapy. In line with this development, evidence from recent studies suggests that deep brain stimulation might enhance memory functions when particular brain areas are stimulated. Of particular interest in our study, electrical stimulation of the Prefrontal Cortex induced striking antidepressant activity in both patients and animals studies (see our recent study, Lim et al., 2015 Translational Psychiatry; http://www.nature.com/tp/journal/v5/n3/full/tp201524a.html). However, no studies have shown the putative role of Prefrontal Cortex deep brain stimulation in learning and memory performance. In our finding, we have shown that deep brain stimulation of this region (Prefrontal Cortex) improved the short-term and long-term memory by a very important mechanism, which led to the formation of new brain cells in another region of the brain called the hippocampus, which is also involved in memory. Therefore, our findings suggest that deep brain stimulation of the Prefrontal Cortex has the potential to be developed into a therapy to treat dementia and other conditions that lead to memory loss in humans.
(more…)
MedicalResearch.com Interview with:
Dr. Rebecca E. Amariglio Ph.D.
Massachusetts Alzheimers Disease Research CenterMassachusetts General Hospital
Medical Research: What is the background for this study? What are the main findings?Dr. Amariglio: As the field of Alzheimer’s disease moves towards early detection and treatment, new tests that can measure very subtle changes in cognitive functioning are needed. A new instrument developed by the Alzheimer’s Disease Cooperative Study that measures subjective report of memory changes of both the study participant and a study partner (usually a family member) was associated with cognitive decline over four years. Specifically, greater report of memory concerns was associated with worse memory performance over time.
(more…)
MedicalResearch.com Interview with:
Ashok K. Shetty, Ph.D.
Professor and Director of NeurosciencesInstitute for Regenerative Medicine and Department of Molecular and Cellular Medicine Texas A&M Health Science Center College of Medicine, Temple, TX Research Career Scientist, Central Texas Veterans Health Care System (CTVHCS), Temple, TX
Medical Research: What is the background for this study?
Prof. Shetty: Hippocampus is a region in the brain important for maintaining functions such as learning, memory and mood. However, this region is highly vulnerable to aging and brain insults. Previous research has shown that diminished function in the dentate gyrus region of the hippocampus is one of the key reasons for memory impairments seen in old age. Dentate gyrus is also one of the few regions in the brain where neural stem cells generate new neurons on a daily basis, also referred to as "adult neurogenesis". Studies have suggested that a significant fraction of newly born neurons mature, get incorporated into the existing hippocampus circuitry and contribute to learning, formation of new memories, and normal mood. However, with aging, the dentate gyrus shows decreased function with some conspicuous structural changes, which include reduced production of new neurons, diminished microvasculature implying reduced blood flow, and occurrence of hypertrophy of astrocytes and activated microglia, signs of chronic low-level inflammation. Because alterations such as reduced neurogenesis, decreased blood flow and brain inflammation can contribute to memory and mood impairments, the idea that drugs that are efficacious for mitigating these changes may preserve memory and mood function in old age has emerged. Such drugs may be prescribed to the aging population if they are efficacious for maintaining normal cognitive and mood function in old age with no or minimal side effects.
Medical Research: What is the rationale for choosing resveratrol for preventing age-related memory dysfunction in this study?Prof. Shetty: Administration of resveratrol, a naturally occurring polyphenol found in the skin of red grapes, red wine, peanuts and some berries, appeared suitable for counteracting age-related detrimental changes in the hippocampus. This is because, previous studies have shown that resveratrol has ability to promote the formation of new capillaries (through pro-angiogenic effects) and to suppress oxidative stress and inflammation (via antioxidant and antiinflammatory effects) with no adverse side effects. Other studies have also reported that resveratrol can mediate extension of the life span and delayed onset of age related diseases. More importantly, a recent human study suggested that a reasonably lower dose of resveratrol intake for 26 weeks is good enough to improve memory performance as well as hippocampus functional connectivity in 23 healthy overweight older individuals (Witte et al., J. Neurosci., 34: 7862-7870, 2014).
(more…)
MedicalResearch.com Interview with:Peter Bayley PhD
War Related Illness and Injury Study Center
Veteran Affairs Palo Alto Health Care System
Palo Alto, California
MedicalResearch.com: What is the background for this study? What are the main findings?Dr. Bayley: There is currently widespread interest and debate surrounding the topic of screening for Alzheimer’s disease and other types of dementia The study describes results from National Memory Screening Day in 2010, an annual community event sponsored by the Alzheimer Foundation of America. Face-to-face screening takes place in a private setting; only the individual being tested and the screener are present. The memory screening consists of one of seven validated cognitive tests: the GPCOG (General Practitioner Assessment of Cognition), MINI-COG, MIS (Memory Impairment Screen), the BAS (Brief Alzheimer’s Screening), Kokmen Short Test of Mental Status, Mini-Mental State Examination, Montreal Cognitive Assessment, or the Saint Louis University Mental Status Examination. Participants with scores below cutoff for possible dementia are encouraged to bring the results to their healthcare professional for follow-up and/or inclusion in medical files.
We report the results from a subset of 3,064 participants. Overall, 11.7% failed one of the memory screening tests. As expected, failure rates were higher in older and less-educated participants (P’s < .05). Subjective memory concerns were associated with a 40% greater failure rate for persons of similar age and education but no memory concerns (odds ratio = 1.4, 95% confidence interval = 1.07–1.78). However, most individuals who expressed concern about their memories passed the screening tests (54-96%, depending on age and education).
(more…)
MedicalResearch.com Interview with:
Scott M. Hayes, Ph.D. Associate Director
Neuroimaging Research for Veterans Center
Memory Disorders Research Center
VA Boston Healthcare System
Assistant Professor of Psychiatry
Boston University School of Medicine
Medical Research: What is the background for this study? What are the main findings?
Dr. Hayes: Studies with rodents have demonstrated that physical activity positively impacts memory, whereas human studies have tended to emphasize a relationship with executive function—which refers to one’s ability to plan, organize, and manipulate information in one’s mind. To clarify the relationship between fitness, cognition, and aging, we directly assessed cardiorespiratory fitness (heart and lung function) using the gold standard in the field, a graded treadmill test, and assessed both memory and executive functions in young and older adults. Our results showed that cardiorespiratory fitness was positively associated with memory and executive functions in older adults, but not young adults. In fact, on tests of executive functions, older adults with higher levels of cardiorespiratory fitness performed as well as younger adults. The impact of cardiorespiratory fitness may be age-dependent. Young adults, who are at their peak in terms of memory performance, may exhibit minimal associations with cardiorespiratory fitness. In contrast, cardiorespiratory fitness likely has a larger impact in older adults by attenuating age-related decline in memory.
(more…)
MedicalResearch.com Interview with:
M. Arfan Ikram, MD, PhD,and Ayesha Sajjad, MD
Department of Epidemiology
Erasmus University Medical Center, Rotterdam
Rotterdam, The NetherlandsMedical Research: What is the background for this study? What are the main findings?
Response: The occurrence of cognitive impairment and dementia after a stroke event are already known. Since these neuro-degenerative processes and stroke share vascular pathways in their pathogenesis such as small vessel disease, we aimed to study whether early cognitive impairment can be predictive of stroke onset in the elderly. We also hypothesized that a higher cognitive reserve (due to higher education attainment) may mask early symptoms of memory loss and thus put these older individuals at a higher risk of stroke. We found that self-reported subjective memory complaints as answered by a single question: “ Do you have memory complaints?” was highly predictive of stroke especially in older persons who were highly educated. In comparison, objective measures of cognitive impairment such as MMSE did not show any association with the risk of stroke.
(more…)
MedicalResearch.com Interview with:
Sandra Barral Rodriguez, Ph.D
Assistant Professor
G. H. Sergievsky Center & Taub Institute
Columbia University Medical Center
New York, NY 10032
Medical Research: What is the background for this study? What are the main findings?Dr. Barral: We already know that there is a substantial genetic contribution to the variability observed in different cognitive tasks including memory performance. Previous work reported heritability estimates for episodic memory ranging between 30% and 60%. However, we can’t fully explain why some individuals demonstrate a better memory performance in late life, while others do not.
We have previously defined a cognitive endophenotype based on exceptional episodic memory performance (EEM) and demonstrated that there is a familial aggregation of EEM in families selected on their basis of their exceptional survival, the Long Life Family Study. We performed genome-wide linkage analysis of long-lived families selected on the basis of their exceptional episodic memory and the follow-up SNP association analysis with episodic memory in four independent cohorts of more than 4,000 non-demented elderly cohorts.
Our results provide strong evidence for potential candidate genes related to exceptional episodic memory on 6q24.
(more…)
MedicalResearch.com Interview with
Joshua Sandry, Ph.D.
Neuropsychology & Neuroscience Research
Kessler Foundation, West Orange, NJ
Assistant Professor, Department of Physical Medicine and Rehabilitation
Rutgers New Jersey Medical School
Medical Research: What is the background for this study? What are the main findings?
Dr. Sandry: We were interested in better understanding the relationship between cognitive reserve and long-term memory impairment in moderate to severe Traumatic Brain Injury, from a cognitive perspective. The theory of cognitive reserve suggests that individuals who engage in intellectually enriching activities may be less susceptible to the negative cognitive consequences of long-term memory impairment that often accompanies neurological disorders. There’s significant evidence in support of cognitive reserve; however, it’s somewhat unclear what particular cognitive processes are involved in this relationship and how those cognitive processes may differ across high and low reserve individuals. We derived our predictions on the basis of well-established cognitive theory and found that working memory capacity partially mediates the cognitive reserve – long-term memory relationship in Traumatic Brain Injury. Or to put it another way, working memory may be one underlying cognitive process involved in this relationship. Importantly, this finding corroborates some recent related work we have conducted in multiple sclerosis.
(more…)
MedicalResearch.com Interview with:
Stephen D. Ginsberg, Ph.D., Associate Professor
Departments of Psychiatry and Physiology & Neuroscience
New York University Langone Medical Center
Center for Dementia Research
Nathan Kline Institute Orangeburg, NY 10962
Medical Research:What is the background for this study? What are the main findings?Dr. Ginsberg: We tested the hypothesis that long-term calorie restriction positively alters gene expression within the hippocampus, a critical learning and memory area vulnerable in aging and Alzheimer’s disease. To test this hypothesis, we conducted experiments on female mice that were given food pellets 30% lower in calories than what was fed to the control group. The mice ate fewer calories derived from carbohydrates. Analyses were performed on mice in middle and old age to assess any differences in gene expression over time. Our data analysis revealed that the mice that were fed a lower calorie diet had fewer changes in approximately 900 genes that are linked to aging and memory. (more…)
MedicalResearch.com Interview with:
Jennifer Choi Tudor, Ph.D. Postdoctoral Fellow
Ted Abel Lab Department of Biology 10-17
Smilow Center for Translational Research
Philadelphia, PA 19104
Medical Research: What is the background for this study? What are the main findings?Dr. Tudor: We (Dr. Tudor, Dr. Abel, and colleagues) are interested in better understanding the molecular changes that occur with sleep deprivation. Previously, we found that the expression of over 500 genes changes with sleep deprivation and that many of the genes were involved with protein synthesis. Upon further investigation, we found that 5 hours of sleep deprivation impairs protein synthesis in the hippocampus, a brain region critical for memory. This impairment is due to changes in mammalian target of rapamycin (mTOR) signaling and eukaryotic initiation factor 4E binding protein 2 (4EBP2) is critical to this process. When we boosted levels of 4EBP2 in the hippocampus, mice that were sleep deprived were resistant to the detrimental effects of sleep deprivation on memory.
(more…)
MedicalResearch.com Interview Invitation with:
Dr. Heekyeong Park
Assistant Professor of Psychology
University of Texas at Arlington
Medical Research: What is the background for this study? What are the main findings?Dr. Park: This study shows that music experts with extensive musical training may have altered neural processing related to improved memory.
There has been much interest in the beneficial effects of musical training on cognition. Notably, musical training has been reported to boost processing of verbal material. Previous studies have indicated that musical training was related to superior verbal working memory and that these differences in musical training were associated with differences in neural activity in brain regions important for verbal processing. However, it was not clear whether musical training impacts memory in general, beyond working memory for verbal items. By recruiting professional musicians with vast instrumental training, we investigated if extensive musical training has a broad impact on memory with corresponding changes in the brain.
For this study, we compared highly trained musicians (10+ years of experience) and individuals with little or no formal musical training on working memory and long-term memory tasks. Each memory task included both verbal and pictorial items. We measured memory accuracy on tasks and scalp-recorded changes in the brain’s electrical activity (ERPs) while participants studied and remembered items. Musicians showed enhanced performance on the working memory task for both words and pictures. For the long-term memory task, musicians also remembered studied pictures better than non-musicians. These behavioral findings demonstrate the relationship between extensive musical training and improved memory broadly. ERP waveforms were also different between musicians and non-musicians while they performed long-term memory tasks.
(more…)
MedicalResearch.com Interview with: Scott A. Small, MD
Boris and Rose Katz Professor of Neurology
Division of Aging and Dementia
Director, Alzheimer's Disease Research Center
Taub Institute for Research on Alzheimer's Disease and the Aging Brain Department of Neurology, Columbia University New York, NY
Medical Research: What is the background for this study?Dr. Small: Previous work, including from my lab, had shown that changes in a specific part of the brain—the dentate gyrus—are associated with age-related memory decline. Until now, however, the evidence in humans showed only a correlational link, not a causal one. To see if the dentate gyrus is the source of age-related memory decline in humans, we tested whether compounds called cocoa flavanols can improve the function of this brain region and improve memory. Flavanols extracted from cocoa beans had previously been found to improve neuronal connections in the dentate gyrus of mice.
(more…)
MedicalResearch.com Interview with:Professor Emrah Düzel
Director, Institute of Cognitive Neurology and Dementia Research, OvG Univ. Magdeburg, Germany
Institute of Cognitive Neuroscience
University College London
Medical Research: What are the main findings of the study?Professor Düzel:We found that even in old age, intensive and long-term (3 months) aerobic exercise can improve blood flow in the hippocampus, a brain structure that is of critical importance for memory. The increase in blood flow is evident during a resting state and this means that the exercise improves the overall perfusion of the hippocampus. Such effects had previously only been reported in young adults. As previously observed in young adults, the change in blood flow after exercise is related to the improvement of specific memory skills. We found the closest relationship between improved blood flow and recognition memory for complex objects. This is interesting because this type of memory is likely to benefit from “pattern separation”, a process that in animal studies of exercise is tightly associated with hippocampal neurogenesis.
However, we also found that the exercise-related improvement in hippocampal blood flow and in recognition memory was absent in the older seniors of our study cohort. Those who were beyond 70 did not show any improvement. We reasoned that this may have been due to higher levels of stress in the older seniors. Therefore, we investigated whether elevated serum cortisol levels dampened the benefits of exercise in the older seniors. But this was not the case making it unlikely that stress levels can account for these findings.
(more…)
MedicalResearch.com Interview with: Richard J. Kryscio, PhD, Professor
Sanders-Brown Center on Aging
University of Kentucky
Medical Research: What are the main findings of the study?Dr. Kryscio: We followed 531 elderly over time assessing their cognition annually; of these 105 (about 20%) eventually were diagnosed with a serious cognitive impairment (either a mild cognitive impairment or a dementia) and 77% of the latter declared a subjective memory complaint prior to the diagnosis of the impairment. In brief, declaration of a memory problem put a subject at three times the risk of a future impairment.
(more…)
MedicalResearch.com Interview with: Elizabeth Devore, ScD
Associate Epidemiologist
Brigham and Women’s Hospital
Instructor in Medicine, Harvard Medical School
MedicalResearch.com: What are the main findings of the study?Dr. Devore: In this study, we examined sleep duration and memory performance in a group of ~15,000 women participating in the Nurses’ Health Study. We found that women with sleep durations of 5 or fewer hours/day or 9 or more hours/day, either in midlife or later life, had worse memory at older ages than those sleeping 7 hours/day. In addition, women with sleep durations that changed by two or more hours/day from midlife to later life performed worse on memory tests compared to those whose sleep duration did not change during that time period.The magnitude of these memory differences was approximately equivalent to being 1-2 years older in age.
(more…)
MedicalResearch.com Interview with:Dr. Erin Abner Ph.D.
Assistant Professor of Epidemiology
University of Kentucky College of Public Health
Lexington, Kentucky
MedicalResearch.com: What are the main findings of the study?Dr. Abner: The findings from this study are preliminary results from The Prevention of Alzheimer’s Disease with Vitamin E and Selenium Study. This early look at the data indicates that very simple measures of memory change, in this case asking older men with no cognitive impairment about changes in their memory over the past year, and whether they believe those changes are a problem, can be used to predict cognitive impairment years later. Men who said at study baseline that the changes in their memory represented problems to them were over twice as likely as men who did not complain to develop clinically detectable cognitive impairment during follow-up. This is exciting because the field of Alzheimer’s research is moving toward earlier intervention in the disease process. As of now, our best methods for identifying individuals without cognitive impairment who are likely to develop Alzheimer’s disease in the future are procedures that many people find intimidating, like lumbar puncture and PET scanning. Identifying older adults at high risk for future cognitive impairment with low-cost, non-invasive screening techniques would help researchers to target potential therapies to the people who stand to benefit the most.
(more…)
MedicalResearch.com Interview with:Dr. Matthew J. Smith PhD
Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, 710 N. Lake Shore Drive, 13th Floor, Abbott Hall, Chicago, IL 60611
MedicalResearch.com: What are the main findings of the study?Dr. Smith:We observed that the shapes of brain structures involved in a working memory brain circuit seemed to collapse inward in a similar fashion among both of the groups that had a history of daily cannabis use. These cannabis-related changes in shape were directly related to the participants’ poor performance on working memory tasks. Some of the shape abnormalities were more severe in the group with schizophrenia and the history of daily cannabis use. We also found that participants with an earlier age of daily cannabis use had more abnormal brain shapes.
(more…)
MedicalResearch.com Interview with:Lucia Kerti MA
From the Departments of Neurology
Charité–University Medicine, Berlin
MedicalResearch.com: What are the main findings of the study?Answer: The results of our study on 141 healthy older people suggest that chronically higher blood glucose levels may have a negative influence on memory performance even in the absence of type 2 diabetes or even pre-diabetes. Moreover, our findings indicate that elevated blood glucose levels impair the functioning of brain areas like the hippocampus, a structure particularly relevant for memory. An important novel aspect in our study was the additional analysis of diffusion tensor imaging-based mean diffusivity within the hippocampal, which allowed us to obtain information on microstructure. We here provided first-time data of an association between higher blood glucose levels and lower hippocampal microstructure. Decreased hippocampal microstructure as measured by mean diffusivity may reflect a disruption of neuronal membranes and increased extracellular water content, leading to decreased signaling within and between hippocampal cells. Thus, information transfer between cells, indispensable for memory encoding, storage and retrieval, would be compromised. In sum, our data suggest that chronically higher blood glucose levels even within the "normal range" may decrease memory functions, possibly in part mediated by microstructural changes within the hippocampus.
(more…)
This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish.AcceptRejectRead More
Privacy & Cookies Policy
Privacy Overview
This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are as essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may have an effect on your browsing experience.
Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
