Author Interviews, Memory / 14.02.2024 Interview with: Prof. Frederic Meunier PhD Professor and Academic Senior Group/Unit Leader/Supervisor Queensland Brain Institute and Isaac O Akefe DVM, PhD Clem Jones Centre for Ageing Dementia Research Queensland Brain Institute The University of Queensland St Lucia Academy for Medical Education, Medical School Brisbane QLD Australia What is the background for this study? Response: The brain is the body’s fattiest organ, with fatty compounds called lipids making up 60% of its weight. Fatty acids are the building blocks of a class of lipids called phospholipids. In our study, we first showed that levels of saturated fatty acids increase in the brain during neuronal communication and long-term memory formation, but we didn’t know what was causing these changes. (more…)
Author Interviews, Cognitive Issues, Memory / 07.08.2023 Interview with: Michael Leon, Professor emeritusDepartment of Neurobiology and BehaviorCenter for the Neurobiology of Learning and MemoryInstitute for Memory Impairments and Neurological DisordersUniversity of California Irvine What is the background for this study?  What types of aromas were employed? Response: The olfactory system is the only sense to have a direct “superhighway” access to the memory centers of the brain. The other senses can contribute to the health of the memory centers, but they have to take the brain's “side streets” to get there and consequently have much less impact on the health of those centers. If there is olfactory loss for any reason, the memory centers start to deteriorate. Stimulation of those memory centers with odors allows those centers to allow for better memory. We used naturally occurring pleasant odors: rose, orange, eucalyptus, lemon, peppermint, rosemary, and lavender. (more…)
AHA Journals, Author Interviews, Blood Pressure - Hypertension, Cognitive Issues, Memory / 21.06.2021 Interview with: Daniel A. Nation, Ph.D., Associate Professor of Psychological Science Institute for Memory Impairments and Neurological Disorders University of California, Irvin 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. (more…)
Alzheimer's - Dementia, Author Interviews, Cognitive Issues, Memory, Surgical Research / 23.01.2021 Interview with: Pascual Sánchez-Juan, MD, PhD Servicio de Neurología Hospital Universitario "Marqués de Valdecilla" Unidad de Deterioro Cognitivo Director científico Biobanco Valdecilla Avda Marqués de Valdecilla s/n What is the background for this study? Response: Alzheimer's disease is one of the greatest public health challenges. From the moment the first lesions appear in the brain to the clinical manifestations, up to 20 years can pass. Today we can detect the presence of these initial lesions through biochemical markers such as amyloid-β, which is one of the main proteins accumulated in the brains of Alzheimer's patients. The prevalence of cerebral amyloid-β pathology in cognitively asymptomatic individuals increases with age. It has been estimated that 21.1% of the population at the age of 65 will have a positive amyloid scan or a pathological cerebrospinal fluid (CSF) amyloid-β determination, and which will double by the age of 90. Due to the aging of our societies and advances made in medical care, an increasing number of elderly and more fragile people are considered candidates for major surgery. In preoperative screenings, respiratory and cardiovascular functions are routinely checked; however, it is not commonly assessed how the brain is going to cope with the intervention. In the clinic, the patient’s relatives frequently tell us that the memory problems began after a surgical procedure or a hospital admission. This posed us the following question: is this just a recall bias or has surgery triggered the appearance of the symptoms in a previously affected brain?” (more…)
Author Interviews, Education, Memory, Pediatrics / 08.10.2020 Interview with: Leonie Margarita Kausel, PhD Postdoctoral Researcher Development University Santiago, Chile What is the background for this study? Response: As a violin teacher, I observed the positive impact on many levels that musical training has on children and as a scientist (Biochemist), I was intrigued to be able to show this with data. I thought this was very important, because in my experience childhood music education can give you so much joy and important skills for life, but it is often not considered to be important in educational settings. After attending a seminar on education and neuroscience, I discovered that this discipline could allow me to investigate this in a scientific manner. This inspired me to enter the Neuroscience PhD program at the Pontificia Universidad Católica de Chile where I was lucky to work with Dr. Francisco Aboitiz, who has vast experience in attention research (ADHD) and is an international expert in language and evolution. At that time Dr. Mary Elizabeth Sutherland was making her postdoc at the lab, and she had worked with Dr. Robert Zatorre, one of the leading researchers in music and the brain. Also, I was lucky to work with Dr. Francisco Zamorano, a pioneer of fMRI research in Chile. So together we designed the research. :)  Also, I am very grateful that I could make a research stay at the Lab of Dr. Gottfried Schalug, who is also a pioneer in the research of music and the brain, and who inspired me to do this research since he wrote the first papers that I read about this subject.  (more…)
Author Interviews, Cannabis, Cognitive Issues, Memory, Pediatrics / 04.09.2020 Interview with: Jarrod Ellingson PhD Assistant Professor Department of Psychiatry Anschutz Medical Campus University of Colorado Denver What is the background for this study? What are the main findings? Response: We know that cannabis use is associated with many negative outcomes, but there could be many of reasons for that. For example, socioeconomic factors and peer influences both affect adolescent cannabis use and poorer cognitive functioning. To account for some of those risk factors, we studied nearly 600 sibling pairs with moderate to heavy cannabis use. We found that, as a person uses more cannabis than their sibling, they tend to have worse memory recall than their sibling. (more…)
Author Interviews, Memory / 04.10.2019 Interview with: Noah Forrin, PhD Postdoctoral fellow in Psychology University of Waterloo What is the background for this study? Response: Everyday experience suggests that people have poor memory for information that they encounter prior to their own public performance.  For example, prior to giving a presentation at school or at work, people often struggle to remember information from a presentation that occurred before their own. n our study, we tested the hypothesis that performance anticipation reduces memory for pre-performance information.  We found that when participants anticipated a simple upcoming presentation--reading words out loud in front of someone else--their memory was diminished prior to reading those words out loud.  Memory may be reduced in this way because people are thinking about their upcoming performance or because they are anxious (i.e., performance anxiety). (more…)
Alzheimer's - Dementia, Author Interviews, Memory, Pharmacology / 12.09.2019 Interview with: James O’Donnell, PhD Dean and professor Pharmacy and Pharmaceutical Sciences University at Buffalo School of Pharmacy Ying Xu, MD, PhD Research associate professor University at Buffalo School of Pharmacy and Pharmaceutical SciencesYing Xu, MD, PhD Research associate professor University at Buffalo School of Pharmacy and Pharmaceutical Sciences What is the background for this study? Response: We have been studying cyclic nucleotide phosphodiesterase (PDE), an enzyme, for quite a while as a potential target for neuropsychiatric disease.  One aspect involves the effects of PDE inhibitors on memory.  This was prompted by our earlier finding that one form of the enzyme, PDE4, is in the NMDA receptor signaling pathway in neurons; this pathway has been implicated in memory.  (more…)
Alzheimer's - Dementia, Author Interviews, Genetic Research, Memory / 23.08.2019 Interview with: Dr. Claude Alain PhD Senior Scientist Baycrest's Rotman Research Institute What is the background for this study? Response: Adults carrying a gene associated with a higher risk of Alzheimer’s disease had a harder time accessing recently acquired knowledge, even though they didn’t show any symptoms of memory problems. What are the main findings?  Response: Researchers found that older adults carrying a specific strain of the gene, apolipoprotein E4, otherwise known as APOE4, weren’t able to tap into information they had just learned to assist them on a listening test. These findings suggest greater difficulty for these individuals to access knowledge from their memory to guide their attention in ways that would have improved their performance. This work could lead to the development of new ways to detect individuals at risk. (more…)
Author Interviews, Memory, NIH, Sleep Disorders / 17.04.2019 Interview with: Leonardo G. Cohen, M.D., Ph.D., Senior Investigator Marlene Bönstrup, M.D., Postdoctoral fellow in  Dr. Cohen's lab NIH's National Institute of Neurological Disorders and Stroke What is the background for this study? What are the main findings?  Response: Learning a new skill is typically divided into online (during practice) and offline (after practice has ended) components. Particularly motor skill learning occurs to a considerable degree offline, meaning that performance further improves even after practice has ended. A single practice session itself however, is typically divided into short (level of seconds) periods of practice and rest. In this study, we set out to investigate the contribution of those short periods of practice and rest to the learning during a practice session (i.e. online learning). We found that during early motor skill learning, when most of the total learning occurs, performance improvements actually precipitate during short periods of rest whereas during practice periods, performance mostly stagnated. We found a signature of neural activity predictive of those performance improvements during rest: The lower the beta rhythmic activity in the parietofrontal regions of the brain during those short periods of rest, the higher were participant’s performance jumps.  (more…)
Author Interviews, Cognitive Issues, Memory, University Texas / 16.04.2019 Interview with: Dr. Sandra Bond Chapman PhD Founder and Chief Director, Center for BrainHealth, Co-Leader, The BrainHealth Project University of Texas, Dallas What is the background for this study? Response: Finding effective treatments to reverse or slow rates of cognitive decline for those at risk for developing dementia is one of the most important and urgent challenges of the 21st century. Brain stimulation is gaining attention as a viable intervention to increase neuroplasticity when used in isolation or when combined with cognitive training regimens. Given the growing evidence that certain cognitive training protocols, such as SMART, benefit people with Mild Cognitive Impairment (MCI), a population that is vulnerable to Alzheimer’s disease, we were interested in exploring whether we could further increase the gains from cognitive training (i.e., SMART) when the training was preceded by brain stimulation using tDCS.  (more…)
Author Interviews, Memory, Sleep Disorders / 11.02.2019 Interview with: Marc Züst, PhD University of Bern Department of Psychology Division of Experimental Psychology and Neuropsychology Switzerland What is the background for this study? What are the main findings? Response: Slow wave sleep (deep sleep) is known to be very important for memory reorganization. The brain goes through the memory traces that were created during wakefulness and strengthens the important ones, while unimportant ones are weakened or deleted to make room for new learning the next day. This happens during the peaks of the eponymous slow waves, also called up-states, where the brain is highly active and interconnected. Up-states last for about 0.5 sec before transitioning into down-states, where the brain is relatively silent. Based on these findings, we hypothesized that up-states constitute windows of opportunity to learn new information during slow wave sleep: The "channels are open", and the brain is already performing memory functions. The results of our study support this hypothesis. We found that, if we repeatedly managed to synchronize presentation of word pairs with up-states, memory for these pairs was best. Moreover, we find a dose-response function: The more often word pairs hit up-states, the better the memory. On top of that, fMRI during the retrieval test suggests that the same brain regions are involved in sleep learning as are involved in learning during wakefulness. (more…)
Author Interviews, Memory, Sleep Disorders / 25.01.2019 Interview with: "Tonight, I am grateful for an old rocking chair that had the power to quell my crying baby after hours of fussing. It has rocked several generations on my dad's side and I like to think its legacy of comfort can be magical from time to time. #aboynamedfox" by mandaloo is licensed under CC BY-NC-SA 2.0. To view a copy of this license, visit: Aurore Perrault, PhD Student Department of Neuroscience, Faculty of Medicine University of Geneva Geneva, Switzerland What is the background for this study?   Response: We naturally rock babies to sleep. Yet, we also have plenty of anecdotal reports of adults falling asleep faster when in a train or a car, as well as a feeling of relaxation in a hammock. Our companion paper on mice (Kompotis et a., 2019 – same issue in Current Biology) clearly established that the beneficial effects of rocking on sleep relied on the activation of the vestibular system and might thus suggest some shared neurophysiological mechanisms in mammals. (more…)
Author Interviews, Memory, OBGYNE / 06.12.2018 Interview with: Heather A. Bimonte-Nelson, Ph.D. Professor, Barrett Honors Faculty Department of Psychology Arizona State University What is the background for this study? What are the main findings? Response: The dogma in the field is that the nonpregnant uterus is dormant, and therefore it has not necessarily been of interest to study. Textbooks have described the nonpregnant uterus as “quiescent,” “dormant,” and “useless.” When I was in graduate school studying endocrinology, I read statements in books saying that the sole purpose of the uterus is for gestation. However, all women aging into midlife will experience some type of menopause, and some of these women will undergo surgical menopause via removal of all, or a part of, their reproductive tracts. Research evaluating reproductive tract-brain connections has grown quite a bit in the last few decades. For example, the ovary-brain connection has been focused on quite a bit, and we now know that hormones coming from the ovaries (such as estrogens and progesterone) can affect more than reproduction, and can impact brain functioning. While the uterus-brain connection is not well understood, there is research indicating that the uterus and autonomic nervous system communicate directly. We also know that hormones released from the ovaries impact the uterus. Therefore, there is a uterus-ovary-brain triad system. This uterus-ovary-brain triad has undergone little scientific investigation for functions outside of reproduction. Given that by age 60 one in three women experience hysterectomy, thereby interrupting this uterus-ovary-brain triad system, we believe it is important to understand the effects of variants of surgical menopause including hysterectomy. This led to our current evaluation testing multiple variations in surgical menopause using a rat model, where we tested the effects of uterus removal alone (hysterectomy), ovarian removal alone, or uterus plus ovarian removal. (more…)
Author Interviews, Memory, Pediatrics, Sleep Disorders / 22.08.2018 Interview with: Dr. Rebecca Spencer PhD Associate Professor Department of Psychological and Brain Sciences University of Massachusetts What is the background for this study? What are the main findings? Response: We know that in young adults, sleep contributes to emotion processing. We wondered if naps work similarly for preschool children.  To look at this, we had children learn an emotional memory task and then either take a nap or stay awake.  We then tested their memory after that interval and again the next day. We found that when children napped, they had better memory for those items the next day than if they did not nap.  That the naps seem to support memory (even if in a delayed fashion) seems consistent with the observation of parents and preschool teachers that children are often emotionally dysregulated if they do not nap. (more…)
Author Interviews, Cannabis, Cognitive Issues, Memory / 18.08.2018 Interview with: Dr. Italia V. Rolle, PhD and Dr. Tim McAfee, MD Office on Smoking and Health National Center for Chronic Disease Prevention and Health Promotion CDC Ana Maria Sebastião, PhD Professor of Pharmacology and Neurosciences Director Institute of Pharmacology and Neurosciences, Faculty of Medicine and Francisco Mouro, PhD Unit of Neurosciences, Institute of Molecular Medicine University of Lisbon, Portugal What is the background for this study? What are the main findings?  Response: There is pressing need to comprehend how cannabinoid exposure impacts brain functioning. While cannabinoid-related research has increased exponentially in the last decade, the mechanisms through which cannabinoids affect brain functioning are still elusive. Specifically, we need to know how prolonged cannabinoid exposure affects important cognitive processes, such as memory, and also find the roots of those effects. This is particularly relevant considering that several countries have already approved cannabis-based medicines. In this sense, our work sheds new light into the mechanisms underlaying the memory-deficits provoked by a continuous exposure to a cannabinoid drug. More precisely, using brain imaging techniques, we found that long-term exposure to a synthetic cannabinoid drug impairs the ability of key brain regions involved in learning and memory to communicate with each other. Our data points to the necessity of considering cannabinoid actions in a broader perspective, including brain circuitry and communication.  (more…)
Author Interviews, Cognitive Issues, Memory / 05.08.2018 Interview with: Dr Antonina Pereira - CPsychol, PhD, FHEA, AFBPsS Head of Department of Psychology & Counselling University of Chichester Chichester, West Sussex UK What is the background for this study? What are the main findings?  Response: Prospective memory (PM) is the ability to remember to perform future activities, such as remembering to take medication or remembering to attend an appointment. Prospective memory tasks pervade our daily lives, and PM failures, although sometimes merely annoying (e.g., forgetting an umbrella at home on a rainy day), can have serious and even life-threatening consequences (e.g., forgetting to turn off the stove). The fulfilment of such delayed intended actions can indeed be an early indicator of Alzheimer’s disease, with prospective memory failures representing one of the most prominent memory concerns in older adulthood and a fundamental requirement for independent living across the lifespan. We aimed to address this issue by exploring the potential benefits of a purposefully designed technique, encoded enactment, where participants were encouraged to act through the activity they must remember to do. This particular study was the fruit of an international research collaboration led by the University of Chichester and including members from Radboud University Nijmegen, Sussex Partnership NHS Foundation Trust and the Faculty of Medicine of the University of Lisbon. Our team has explored the potential benefits of this specific encoding strategy for healthy younger adults, healthy older adults as well as for patients with mild cognitive impairment. Results were very encouraging: All age groups reported improvement in prospective memory, but this was particularly evident in older patients with mild cognitive impairment, that is, potentially in the early stages of Alzheimer’s disease. The study suggests that encouraging people in this category to adopt enactment as a means to enhance prospective memory could result in them leading independent, autonomous lives for longer. (more…)
Author Interviews, Memory, Technology / 15.06.2018 Interview with: Eric Krokos 5th-year Ph.D. student in computer science Augmentarium visualization lab University of Maryland What is the background for this study? What are the main findings? Response: I am interested in exploring the use of virtual and augmented reality in high-impact areas like education, medicine, and high-proficiency training. For VR and AR to excel as a learning tool, we felt there needed to be a baseline study on whether people would perceive information better, and thus learn better, in an immersive, virtual environment as opposed to viewing information on a two-dimensional desktop monitor or handheld device. Our comprehensive user-study showed initial results that people are able to recall information using virtual reality—there was an 8.8 percent improvement in recall ability from our study participants using VR. (more…)
Alzheimer's - Dementia, Author Interviews, JAMA, Medical Imaging, Memory / 12.06.2018 Interview with: Arno de Wilde, MD / PhD candidate Department of Neurology & Alzheimer Center Amsterdam Neuroscience VU University Medical Center Amsterdam, the Netherlands What is the background for this study? What are the main findings? Response: Previous studies assessing the clinical utility of amyloid imaging used very selected research populations, limiting the translatability to clinical practice. In contrast, we used an unselected memory clinic cohort, offering amyloid PET to ALL patients visiting our memory clinic, and for the purpose of this study, we implemented amyloid PET in our routine diagnostic work-up. Our results demonstrate that amyloid PET has important consequences, in terms of diagnosis and treatment changes, for a significant number of patients within a situation that closely resembles clinical practice. I think that these results are an important step in 'bridging the gap' between using amyloid PET in a research setting versus daily clinical practice. (more…)
Author Interviews, Memory, Technology / 28.03.2018 Interview with: Robert E. Hampson, PhD Professor, Physiology & Pharmacology School of Medicine Wake Forest What is the background for this study? What are the main findings? Response: There are many diseases and injuries that affect human memory, and many types of memory deficits, from inability to recall stored memories to the inability to make new memories.  We focused on problems with making new memories, and identifying the brain activity associated with those memories.  We found that we could identify when the brain formed "codes" for new memory, and when those codes were incorrect or faulty.  By identifying what both "strong" and "weak" naturally occurring codes should be, we influence the process to strengthen the weak codes, resulting in better memory. (more…)
Author Interviews, Memory, Technology, UC Davis / 31.01.2018 Interview with: Halle Dimsdale-Zucker University of California, Davis Center for Neuroscience | Ph.D. Candidate Dynamic Memory Lab What is the background for this study? What are the main findings? Response: This study sought to test competing models for how different types of retrieved contextual information (spatial, episodic - which is spatial AND temporal information) are supported by the hippocampus and its subfields. We only found differences between the subfields when people were spontaneously reactivating episodic, but not spatial information. This is surprising because a dominant view of the hippocampus is that it is specialized to represent spatial information. What this suggests is that when there is more than just spatial information that can be remembered that the hippocampus is able to flexibly represent whatever information is most task-relevant for remembering and distinguishing items from one another. Intriguingly, we found that different subfields represented shared episodic contextual information and item-unique contextual information. This highlights that our memories need to both link together common features of related events while retaining the event-specific details. (more…)
Author Interviews, Memory, UCLA / 18.12.2017 Interview with: “Cute babies” by daily sunny is licensed under CC BY 2.0Benjamin M. Seitz Doctoral Student Department of Psychology, Learning & Behavior University of California, Los Angeles What is the background for this study? What are the main findings?   Response: The adaptive memory literature is based on two crucial theories. The first is that we process information on different ‘levels’ and these different levels of processing information strongly influence our ability to later remember that information. The second is that our evolutionary history has shaped our cognitive abilities and that these abilities therefore perform optimally when performing tasks related to evolutionary fitness. It has been established that processing words based on their relevancy to an imagined ancestral survival scenario yields incredible memory performance far superior than processing those same words based on their relevancy to similar imagined scenarios that do not involve the survival element or ancestral environment. Our study demonstrates that thinking about raising offspring in an ancestral environment while processing words leads to a similar benefit to recall of those words as when thinking about survival, suggesting the human memory system while also useful in helping our species survive may have also been particularly useful in helping us raise our offspring. (more…)
Author Interviews, Memory / 11.12.2017 Interview with: Beth A. Taylor, PhD Director of Exercise Physiology Research, Hartford Hospital Associate Professor, Kinesiology University of Connecticut What is the background for this study? What are the main findings? Response: Hydroxy-methyl-glutaryl (HMG) CoA reductase inhibitors (statins) are the most effective medications for managing elevated concentrations of low-density lipoprotein cholesterol (LDL-C).  Although statins are generally well-tolerated, they are not without side effects, and mild central nervous system (CNS) complaints such as memory loss and attention decrements are the second most commonly reported adverse effect of these drugs. Studies assessing cognitive effects of statins vary widely and have produced inconclusive findings. Despite the equivocal data on adverse cognitive side effects with statin therapy, in 2012 the FDA announced a safety label change for statins, based on published case reports of memory loss and confusion and data from the Adverse Events Reporting System. One possibility for these equivocal findings is that studies involving the effects of statins on cognition typically have assessed cognitive function using traditional cognitive tests, which may yield small effect sizes and demonstrate high intra-participant variability. This may explain the discrepancy between clinical trials and patient self-reports, and could be addressed by utilizing CNS tests that directly assess brain parameters. To the best of our knowledge and literature review, this study is the first to investigate the effects of statins on the central nervous system by utilizing fMRI to assess brain neural activation in healthy adults treated with 80 mg atorvastatin or placebo. We detected few changes attributable to statin therapy with standardized neuropsychological tests, a finding similar to that from previous clinical trials. However, participants on atorvastatin demonstrated altered patterns of neural activation on vs. off statin compared to participants treated with placebo. Unexpectedly, the treatment groups differed at both timepoints. The clinical implications of these findings are unclear and warrant additional clinical trials. (more…)
Alzheimer's - Dementia, Author Interviews, Johns Hopkins, Memory, Mental Health Research / 04.11.2017 Interview with: Keenan A. Walker, PhD Johns Hopkins University School of Medicine Baltimore, MD What is the background for this study? What are the main findings? Response: There is quite a bit of evidence linking immune function with dementia. For example, several of the risk genes for Alzheimer’s disease are known to play a key role in immune functioning and the regulation of inflammation. We conducted the current study to determine whether systemic inflammation earlier in life might be a risk factor for neurodegeneration decades later. This long temporal window allows us to get closer to understanding causality. That is, which comes first – systemic inflammation or brain volume loss. Using a large community sample, we found that individuals with higher levels of blood inflammatory markers during midlife tended to have smaller brain volumes in select regions and reduced memory ability as older adults. We found the strongest associations between systemic inflammation and brain volume loss in brain regions most vulnerable Alzheimer’s disease. (more…)
Author Interviews, Memory, PTSD / 17.08.2017 Interview with: Jun-Hyeong Cho MD PhD Department of Molecular, Cell and Systems Biology University of California, Riverside Riverside, CA 92521 What is the background for this study? What are the main findings? Response: To survive in a dynamic environment, animals develop fear responses to dangerous situations. For these adaptive fear responses to be developed, the brain must discriminate between different sensory cues and associate only relevant stimuli with aversive events. In our current study, we investigated the neural mechanism how the brain does this, using a mouse model of fear learning and memory. Our study demonstrates that the formation of fear memory associated with an auditory cue requires selective synaptic strengthening in neural pathways that convey the auditory signals to the amygdala, an essential brain area for fear learning and memory. (more…)
Author Interviews, Columbia, Memory / 24.06.2017 Interview with: Samuel Schacher, PhD and Jiangyuan Hu, PhD, Department of Neuroscience Columbia University Medical Cente New York State Psychiatric Institute New York, NY 10032, USA What is the background for this study? What are the main findings? Response: It is well established that learning and memory requires changes in the properties of specific neural circuits in the brain activated by the experience. The long-term storage of the memory is encoded through changes in the function of the synapses within the circuit. Synapses are sites of communication between neurons, and the changes in their function come in two varieties: increases in strength and decreases in strength. The encoding of memories typically requires some combination of these synaptic changes, synaptic plasticity, which can last a long time to contribute to long-term memory. Thus the maintenance of a memory will require the persistent change (long-term synaptic memory) in the function of specific synapses. But memories come in different flavors. In the original experiment by Pavlov, a neutral tone, which dogs ignore, came to predict the immediate appearance of a meal. After several of these pairings, the dogs would become happily excited just with the tone. The same type of conditioning could have a negative valence - the tone could proceed a shock to one of the dog's paw. Now the neutral tone would predict a negative stimulus and the dog would express fearful behavior just with the tone (associative learning). A non-associative form of memory would be the same types of stimuli but without the preceding neutral stimulus. At random times the animal will be given a meal or a shock. The behavior of the animal for some time will take on the positive or negative features of its environment - a contented versus depressed condition. Each of these forms of long-term memory would be maintained by increases in the strength of specific synapses. The questions addressed in our study published in Current Biology, based on previous work in my lab and the lab of my colleague Wayne Sossin at McGill, were: 1) Do the same molecules maintain increases in synaptic strength in the neurons of the circuit after stimuli that produce long-term classical conditioning (associative learning) and long-term sensitization (non-associative learning)? 2) If different molecules maintain the different synaptic memories, is it possible to reverse or erase the different synaptic memories by interfering with the function of the different molecules? 3) If true, can we reverse the different synaptic memories expressed in the same neuron by interfering with the function of the different molecules. (more…)
Author Interviews, Memory / 07.05.2017 Interview with: Michael CTrumbo Sandia National Laboratories Department of Psychology Psychology Clinical Neuroscience Center The University of New Mexico Albuquerque, NM What is the background for this study? What are the main findings? Response: The impetus for this study can be found in claims made by several commercial enterprises that you can get cognitive benefits from brain training games intended to enhance working memory (the amount of information you can hold and manipulate in your mind at one time). However, a burgeoning body of research shows working memory training games often do not provide the benefits claimed. Research led by my colleague Laura Matzen shows evidence that working memory training may actually impair other kinds of memory. A key concept in demonstrating improvement of the working memory system is task transfer – if working memory has been improved, then that improvement should be evident when attempting tasks aside from the trained task, to the extent that these new tasks utilize working memory. Brain stimulation combined with working memory training might work when training by itself falls short because stimulation allows for manipulation of brain plasticity in brain regions that are relevant to working memory task performance. If you’re improving connectivity in a brain region involved in working memory, then you should get transfer to other tasks to the extent that they rely on that same brain region. When you’re having people do tasks in the absence of brain stimulation, it’s not clear if you’re getting this general improvement in working memory brain areas. You might be getting very selective, task kind of improvements due to use of task-specific strategy development. Therefore, the current study was designed to see if noninvasive brain stimulation paired with different types of working memory training might result in improvement not only in the trained task, but in related tasks. The findings suggest that particular parings of stimulation parameters and training programs result in working memory improvement. This is important because working memory is a critical component of many everyday tasks, such as reading and language comprehension, and working memory deficits are common in a number of disease states, such as depression. Working memory decline is also evident as part of the healthy aging process, beginning as early as your mid-20s. Therefore, a safe, reliable way to improve working memory stands to benefit both healthy and clinical populations in a variety of task domains which are critical to achieving a high quality of life. (more…)
Author Interviews, Memory, Nature, PTSD / 05.04.2017 Interview with: Dominik R Bach, PhD, MD University of Zurich What is the background for this study? What are the main findings? Response: Posttraumatic stress disorder (PTSD) can occur after a psychological trauma such as physical violence, abuse, or natural disaster. It is characterised by increased arousal, flashbacks, and nightmares that reflect memories of the trauma. Current therapies include talking therapy, but it is costly and does not work in everybody. This is why we were looking for ways of reducing aversive memories with a drug. In the current study, we found that the antibiotic doxycycline impairs the formation of negative memories in healthy volunteers. To form memories, the brain needs to strengthen connections between neurons. It has recently emerged that for strengthening such connections particular proteins are required that sit between nerve cells, so-called MMPs. They are involved in many disorders outside the brain, such as certain cancers and heart disease. This is how we already know that doxycycline suppresses the activity of MMPs. Since doxycycline is relatively safe and readily accessible, our research was relatively straightforward. 76 healthy volunteers - half women, half men - came to the laboratory and received either placebo (a sugar pill) or 200 mg doxycycline. They then took part in a computer test in which one screen color was often followed by a mildly painful electric shock and another color was not. A week later, volunteers came back to the lab. They were shown the colors again , this time followed by a loud sound but never by shocks. The loud sounds made people blink their eyes - a reflexive response to sudden threat. This eye blink response was measured. Volunteers who had initially been under placebo had stronger eye blink after the color that predicted electric shock than after the other color. This "fear response" is a sensitive measure for memory of negative associations. Strikingly, the fear response was 60% lower in participants who had initially taken doxycycline. (more…)