Working Memory Problems Can Persist Into Adulthood in Children with ADHD

Dr. Graham Murray PhD University Lecturer Department of Psychiatry Addenbrooke's Hospital Cambridge UKMedicalResearch.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.  Continue reading

Commercial Brain Training Device Reduces Working Memory

Laura Steenbergen, MSc., PhD Candidate Cognitive Psychology at Institute of Psychology Leiden UniversityMedicalResearch.com Interview with:
Laura Steenbergen, MSc., PhD Candidate
Cognitive Psychology at Institute of Psychology
Leiden University 

Medical 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 tested is 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.

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Insulin Resistance Linked to Poor Memory Performance

Auriel A. Willette, M.S., Ph.D. Food Science and Human Nutrition Neuroscience Interdepartmental Graduate Program Gerontology Interdepartmental Graduate Program Iowa State University, AmesMedicalResearch.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.

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Deep Brain Stimulation Has Potential to Treat Dementia and Memory Loss

Associate Professor Lim Lee Wei (Sunway University, Malaysia) and Assistant Professor Ajai Vyas (Nanyang Technological University, Singapore) discover a new treatment using deep brain stimulation of the Prefrontal Cortex for dementia.

Associate Professor Lim Lee Wei (Sunway University, Malaysia) and Assistant Professor Ajai Vyas (Nanyang Technological University, Singapore) discover a new treatment using deep brain stimulation of the Prefrontal Cortex for dementia.

MedicalResearch.com Interview with: Dr. Lim Lee Wei
School of Biological Sciences, Nanyang Technological University, Singapore;
Department of Biological Sciences, Sunway University, Malaysia

Medical 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.

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Cognitive Function Test Helps Predict Future Memory Loss

Dr. Rebecca E. Amariglio Ph.D. Massachusetts Alzheimers Disease Research Center Massachusetts General HospitalMedicalResearch.com Interview with:
Dr. Rebecca E. Amariglio Ph.D.
Massachusetts Alzheimers Disease Research Center
Massachusetts 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.
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Resveratrol In Food May Help Maintain Memory and Mood Function in Old Age

Ashok K. Shetty, Ph.D. Professor and Director of Neurosciences Institute 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, TXMedicalResearch.com Interview with:
Ashok K. Shetty, Ph.D.
Professor and Director of Neurosciences
Institute 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).

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Community Based Memory Testing Provides Useful Screening Information

dr-peter-bayleyMedicalResearch.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).

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Cardiorespiratory Fitness May Slow Memory Loss In Older Adults

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 MedicineMedicalResearch.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.

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Complaints of Memory Loss May Signal Increased Stroke Risk

MedicalResearch.com Interview with:
M. Arfan Ikram, MD, PhD,and Ayesha Sajjad, MD

Department of Epidemiology
Erasmus University Medical Center, Rotterdam
Rotterdam, The Netherlands

Medical 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.

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Chromosomal Location of Exceptional Memory Identified

Sandra Barral Rodriguez, Ph.D Assistant Professor G. H. Sergievsky Center & Taub Institute Columbia University Medical Center New York, NY 10032MedicalResearch.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.

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Traumatic Brain Injury: Link Between Cognitive Reserve and Long-Term Memory Impairment

Joshua Sandry, Ph.D. Neuropsychology & Neuroscience Research Kessler Foundation, West Orange, NJ Assistant Professor, Department of Physical Medicine and Rehabilitation Rutgers New Jersey Medical SchoolMedicalResearch.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.

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Lower Calorie Diets May Slow Aging and Memory Loss

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  10962MedicalResearch.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. Continue reading

Sleep Deprivation: Specific Molecular Changes Lead To Memory Impairment

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.
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Musical Training Enhances Long Term Memory

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.

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Cocoa Flavenols May Improve Age-Related Memory Decline

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, New YorkMedicalResearch.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.
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Exercise Improves Brain Blood Flow Up To About Age 70

Professor Emrah Düzel Director, Institute of Cognitive Neuroscience University College LondonMedicalResearch.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.

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Memory Complaints May Presage Increased Risk Of Dementia

Richard J. Kryscio, PhD, Professor Sanders-Brown Center on Aging University of KentuckyMedicalResearch.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.
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Adequate Sleep May Help Preserve Memory at Older Ages

dr_elizabeth_devoreMedicalResearch.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.

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Alzheimer’s Disease: Subjective Memory Complaints May Predict Future Cognitive Decline

Dr. Erin Abner Ph.D. Assistant Professor of Epidemiology University of Kentucky College of Public Health Lexington, KentuckyMedicalResearch.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.

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Cannabis: Heavy Use Associated with Working Memory Deficits

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.
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Memory Performance: Negatively Impacted by Higher Glucose, even in Non-Diabetics

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.

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Episodic Memory Impairments and Tip-of-Tongue Experiences

Prof. Timothy Salthouse Brown-Forman Professor of Psychology Department of Psychology University of Virginia Charlottesville, VA 22904-4400MedicalResearch.com Interview with:
Prof. Timothy Salthouse
Brown-Forman Professor of Psychology
Department of Psychology
University of Virginia
Charlottesville, VA 22904-4400
MedicalResearch.com: What prompted this work?

Prof. Salthouse: I think it is noteworthy that the research originated as an undergraduate project by Arielle Mandell. Ms. Mandell was supported by a University of Virginia Harrison Undergraduate Research Award while she was doing the research, and a report of the research served as her Distinguished Major Thesis.

The research was prompted by the observation that according to self-reports, tip-of-the-tongue experiences occur more and more frequently with increased age, and often seem to be associated with concerns about memory decline and possibly impending dementia. We wondered

  1. 1) whether these self-reports are valid, and
  2. 2) if they are valid, do they truly indicate age-related failures of the type of memory used in the diagnosis of dementia.

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Methamphetamine: Research Aims to Disrupt Drug-Associated Memories

MedicalResearch.com Interview with:

Ph.D., Neurobiology & Behavior and Center for the Neurobiology of Learning & Memory (2005), University of California, Irvine, CaliforniaCourtney A. Miller, PhD
Assistant Professor
Department of Metabolism & Aging
Department of Neuroscience
The Scripps Research Institute
Jupiter, FL 33458


MedicalResearch.com: What are the main findings of the study?

Dr. Miller: The relapse rate for drug abusers, smokers and alcoholics is high because abstinence is so difficult. A major factor is the craving that drug associations can trigger. These range from seeing the neighborhood where someone used to buy, in the case of illicit drugs, to social drinking for a smoker. We’ve found a way to disrupt these drug-associated memories without affecting other, more benign memories.
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Intrusive Memories found more commonly during 3rd week of Menstrual cycle

Dr Sunjeev Kamboj

Lecturer in Clinical Psychology
Co-ordinator for International DClinPsy Trainees
http://www.ucl.ac.uk/clinical-psychology/index.htm

MedicalResearch.com: What are the main findings of the study?

Dr. Kamboj: Using a fairly standard approach for this type of research, we measured the frequency of intrusive memories in normal, healthy women after they watched a series of video clips containing distressing scenes. We also measured baseline levels of progesterone and estrogen. We tested three groups of women who, while similar in all respects such age, education level, as well as how they responded to the film, differed in terms of the stage of the menstrual cycle they were in.

Our key finding was that women in the ‘early luteal phase’ – which occurs in the third week of the cycle – had three times as many intrusive memories about the video than women in the first two weeks or fourth week of the cycle.

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Interpolated memory tests reduce mind wandering and improve learning of online lectures


Karl K. Szpunar PhD Department of Psychology, Harvard University, Cambridge, MA 02138MedicalResearch.com Interview with Karl K. Szpunar PhD

Department of Psychology,
Harvard University, Cambridge, MA 02138

MedicalResearch.com:   What are the main findings of the study?

Dr. Szpunar: The results of our experiments demonstrate that students can have difficulty paying attention to online lectures, and that including brief quizzes during lectures can help to alleviate this problem. Specifically, we found that students who were tested throughout a 21-minute long Statistics lecture were half as likely to mind wander during the lecture, three times as likely to take additional notes, and much better able to retain the contents of the lecture at a later time.
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