In 1860, when John Hughlings Jackson was just beginning his career as a physician, neurology did not yet exist as a medical specialty. In fact, at that time there had been little attention paid to developing a standard approach to treating patients with neurological disease. Such an approach was one of Jackson's greatest contributions to neuroscience. He advocated for examining each patient individually in an attempt to identify the biological underpinnings of neurological disorders. This examination, Jackson asserted, should be guided by the tenets of localization of function, which had been popularized by Franz Joseph Gall in the decades before Jackson was born. Concordant with these tenets, Jackson believed that neurological dysfunction could be traced back to dysfunction in specific foci of the nervous system, and the ability to identify the part of the nervous system that was affected to produce a disease was critical for making an accurate diagnosis.Jackson's perspective on understanding neurological diseases is exemplified by his efforts to elucidate the neurobiological origins of epilepsy---the work he is probably best known for. Jackson's observations on epilepsy date back to the very beginning of his medical career. At that time, the most popular explanation for epileptic seizures was that they were associated with abnormal function in a region of the brain known as the corpus striatum, a term that refers to a composite structure consisting of the striatum and the globus pallidus. The corpus striatum was known to be involved with motor functions, which caused it to be implicated in epileptic seizures as well.Jackson, however, began to suspect that the cerebral cortex participated in creating the convulsions that epileptics suffered from during seizures. To support this hypothesis, he cited cases where patients experienced convulsions that primarily struck one side of the body. Very often, Jackson argued, these patients upon autopsy would display damage to the cerebral hemisphere on the opposite side of the body that was affected by seizures.
Watch this 2-Minute Neuroscience video to learn more about epilepsy.Jackson approached the idea that there were certain areas of the cortex devoted to movement with hesitancy for multiple reasons. First, at the time the prevailing view was still that the cortex was unexcitable, and thus would be unlikely to be affected by what Jackson considered to be a disease of increased excitability. Additionally, it was still common in Jackson's time to consider the cortex to be homogenous. Although the concept of localization of function was challenging this idea, many still held the belief that all gray matter in the cortex was equivalent and there were no areas of functional specialization. According to this view, the entire mass of the cortex had to act together to produce some sort of response. Jackson's idea that seizures could be linked to increased excitability in one half of the cortex did not conform to this perspective.In addition to his observations about the link between hemispheric damage and seizures on the other side of the body, Jackson also noted a unique feature of some of the seizures he observed. He pointed out that in certain patients convulsions started in one specific area of the body and then proceeded to travel outward from that area in a predictable fashion. For example, convulsions might begin in the hand and then move up the arm to the face, and then down the same leg on the same side of the body. Or they might start in the foot and travel up the leg, then down the arm and into the hand on the same side of the body.This process, later called the Jacksonian march, would help Jackson to formulate some of his most important ideas about the brain. He hypothesized that there were areas of the cortex that were devoted to controlling the movement of different parts of the body. When excitation spreads throughout the cortex, Jackson posited, it stimulates these different areas one by one, creating the Jacksonian march of convulsions through the patient's body. Furthermore, Jackson suggested that the parts of the body that were capable of the most diverse movements (e.g. hand, face, foot) likely had the most space in the cortex devoted to them.With his observations on epilepsy Jackson was essentially predicting the existence of the motor cortex as well as anticipating the functional arrangement of the gray matter that the motor cortex is made up of. His hypothesis that there was a distinct region of the cerebral cortex devoted to motor function was confirmed in 1870 when Gustav Fritsch and Eduard Hitzig provided experimental evidence of a motor cortex in dogs. The arrangement Jackson envisioned, where one part of the cortex is devoted to one part of the body, we now call somatotopic arrangement. It has been verified by a series of experiments, capped by Wilder Penfield's electrical stimulation studies of the 1930s. It is now common neuroscience knowledge that there are regions of the motor cortex that seem to be devoted specifically to movement of the hands, other regions devoted to the movement of the face, and so on. As Jackson predicted, areas of the body that are involved in more diverse movements generally have more cortical area devoted to them.Jackson's clinical observations of epilepsy and his hypotheses about the motor regions in the cortex accurately predicted what would soon be discovered through experimentation, and acted as a guide for researchers like Fritsch and Hitzig. Thus, Jackson's work contributed significantly to a better understanding of the organization of the cortex, a region that we now consider to be functionally diverse and intricately arranged---a far cry from the idea of cortical homogeneity common in Jackson's time. Additionally, Jackson's development of a more formalized methodology of observation in neurology has caused him to be considered one of the founding fathers of the field.Jackson's contributions to neuroscience, however, were much more extensive than there is room to cover here. He wrote copiously on diverse topics ranging from the evolution of the nervous system to aphasia. At a time when our understanding of the brain was still so lacking in comparison to today, Jackson had a brilliant mind that seemed capable of comprehending brain function in a way that has rarely been replicated in the history of neuroscience.Finger, S. Origins of Neuroscience. New York, NY: Oxford University Press; 1994.York GK, Steinberg DA. An Introduction to the Life and Work of John Hughlings Jackson: Introduction. Med Hist Suppl. 2007; (26): 3–34.... Read more »
York GK, Steinberg DA. (2007) An Introduction to the Life and Work of John Hughlings Jackson. Med Hist Suppl., 3-34. info:/
By Matthew Whitley Imagine you are walking alone in parking lot, when suddenly somebody grabs you by the arm and flashes a knife, demanding your money. Do you A) scream for help, B) try to wrestle the knife away, or C) remove your arm from your shoulder and make a break for it? Disarming your assailant may seem preferable to dis-arming yourself, but for a lizard option C is a likely response. A lizard tail left behind. Image by Metatron at Wikimedia Commons.You likely have heard before that many lizards can break off their tail when trying to make an escape. This ability is called caudal autotomy; autotomy meaning the ability to shed a limb, and caudal simply being a fancy word for tail. Of course, losing a limb is no simple procedure, and lizards possess many specialized features to make caudal autotomy possible. There are two main kinds of caudal autotomy in lizards: intervertebral and intravertebral. Intervertebral refers to when the tail breaks between vertebrae, and is considered the simpler and more primitive form. Intravertebral, on the other hand, involves some more complex features. The word intravertebral refers to fracture planes found in the middle of each vertebra in the middle of the lizard’s tail. At these fracture planes, the bone can easily snap in half. This snapping of bone is performed by the lizard itself—when its tail is caught, muscles surrounding the bone just above where its tail is held squeeze tight until the bone breaks. After the bone breaks, the rest of the tail follows: the skin stretches and breaks, muscles detach, any remaining tissue divides, and—POP—the tail falls off! After snapping your arm off to run from an attacker, you would probably just bleed out in your retreat, but lizards have that covered. In their tails, lizards have sphincters (rings of muscle) along their arteries—vessels that normally carry blood to the tail. When the tail is detached, these sphincters tighten to prevent blood from gushing out. Additionally, their veins, which normally bring blood back from the tail, have valves that prevent blood from flowing backwards, similar to the valves in your heart. And while the lizard makes its escape, the dislocated tail jerks and twitches, which distracts the lizard’s assailant. The tail owes its spastic actions to fast, glycolytic muscles, a variety of muscle that can act quickly and with a lot of force, but wears out quickly. After our reptilian friend has made its daring escape, it has a new problem—it has no tail. A lizard without its tail is at a disadvantage, just as you would be without your arm. Lizards rely on their tails for several functions, including movement, nutrient storage, and social and sexual behaviors. Fortunately, lizards that exercise caudal autotomy can actually re-grow their tails, a process which itself is highly complex. In lieu of a lengthy explanation of another amazing phenomenon, I’ll share this tidbit: to regain lost nutrients and help recover, some lizards have been known to go back and eat their lost tail! So when you tear off your arm to escape a mugger, don’t forget to return to the scene of the crime to self-cannibalize…or maybe just buy some pepper spray beforehand. Here you can see that the lizard is caught by the tail, pops it off and runs away, and the tail is left twitching.Works CitedBateman, P., & Fleming, P. (2009). To cut a long tail short: a review of lizard caudal autotomy studies carried out over the last 20 years Journal of Zoology, 277 (1), 1-14 DOI: 10.1111/j.1469-7998.2008.00484.xClause, A., & Capaldi, E. (2006). Caudal autotomy and regeneration in lizards Journal of Experimental Zoology Part A: Comparative Experimental Biology, 305A (12), 965-973 DOI: 10.1002/jez.a.346Gilbert, E., Payne, S., & Vickaryous, M. (2013). The Anatomy and Histology of Caudal Autotomy and Regeneration in Lizards Physiological and Biochemical Zoology, 86 (6), 631-644 DOI: 10.1086/673889 ... Read more »
Bateman, P., & Fleming, P. (2009) To cut a long tail short: a review of lizard caudal autotomy studies carried out over the last 20 years. Journal of Zoology, 277(1), 1-14. DOI: 10.1111/j.1469-7998.2008.00484.x
Gilbert, E., Payne, S., & Vickaryous, M. (2013) The Anatomy and Histology of Caudal Autotomy and Regeneration in Lizards. Physiological and Biochemical Zoology, 86(6), 631-644. DOI: 10.1086/673889
It is always frustrating when you hear about a financial scam that has target a vulnerable population like the elderly population.Elderly individuals may be targeted for a variety of reasons. First, they often have financial resources. Second, they may be a generally more trustworthy group increasing risk for falling for a scam. Third, elderly may suffer from some age-related brain changes that impair cognition and judgment.A recent research study suggests specific brain deficits may increase vulnerability to financial scams in elderly populations.The designed a study with the following key design elements:Subjects: 13 older adults with a mean age of 70 years who had been financially exploited after age 60. A matched control group of 13 subjects who had been exposed to a financial scam but not been compliantMeasures: Neuropsychological testing of cognition, personality and behavior. Additionally, subjects completed structural and functional brain MRI imagingStatistics: Cases were compared to controls on key study measuresVictims of financial scams showed key differences from controls including:Brain cortex thinning in the anterior insula and posterior temporal regionsFunctional brain connectivity was reduced in default and salience regionsFunctional between network connectivity was increasedHigher scores on measures of anger and hostilityThe authors their findings support a potential role for brain impairment in salience and social cognition regions as markers for risk of financial exploitation.They note significant weaknesses in their study design including a small sample size. Nevertheless, they note clinicians should be aware of potential for increased risk of financial exploitation in elderly with evidence of damage to these key brain regions.This is an important study and goes beyond risk associated with general cognitive decline and early dementia. This study suggests that specific brain regions associated with social cognition may be linked to risk of financial scams in elderly populations.The free full-text manuscript can be accessed by clicking on the link in the citation below.Follow me on Twitter @WRY999Image of brain insula is from my iPad screen shot using the 3D Brain app.Spreng, R., Cassidy, B., Darboh, B., DuPre, E., Lockrow, A., Setton, R., & Turner, G. (2017). Financial Exploitation Is Associated With Structural and Functional Brain Differences in Healthy Older Adults The Journals of Gerontology: Series A DOI: 10.1093/gerona/glx051... Read more »
Spreng, R., Cassidy, B., Darboh, B., DuPre, E., Lockrow, A., Setton, R., & Turner, G. (2017) Financial Exploitation Is Associated With Structural and Functional Brain Differences in Healthy Older Adults. The Journals of Gerontology: Series A. DOI: 10.1093/gerona/glx051
As a neuroscientist, when I think of the retina I am trained to think of a precise set of neurons that functions like a machine, grinding out the visual basis of the world and sending it on to the brain. It … Continue reading →... Read more »
Repérant J, Médina M, Ward R, Miceli D, Kenigfest NB, Rio JP, & Vesselkin NP. (2007) The evolution of the centrifugal visual system of vertebrates. A cladistic analysis and new hypotheses. Brain research reviews, 53(1), 161-97. PMID: 17059846
Theory of Mind (ToM) is a concept describing the ability to understand what another person is thinking or feeling.Today in my neuroscience medicine news review I ran across a novel, interesting and important research study targeting brain development in ToM.Normally developing children develop ToM around 4 years of age. In the study published in Nature Communications, a research team at the Max Planck Institute in Germany studied white matter development in 3 to 4 year old children.Using a series of neuropsychological tasks, they studied white matter development using diffusion tensor brain imaging as it related to ToM skill.The research team was able to identify the following brain development features in ToM:White matter changes in the temperoparietal regions, the precuneus and the medial prefrontal cortexIncreased white matter connectivity between temperoparietal and inferior frontal brain regionsThese changes were independent of development of non-ToM cognitive abilityThe authors note in the discussion section that non-human primates fail to develop explicit ToM cognitive ability. Non-human primate brain show poor arcuate fascicle connectivity. They note that arcuate fascicle white matter connectivity appears to be key for ToM cognitive skills.This manuscript is available in free full-text format and readers with more interest in this study can access the manuscript by clicking on the citation link below.Follow me on Twitter @WRY999Image of white matter tract in human brain is from the iPad app Brain Tutor.Grosse Wiesmann C, Schreiber J, Singer T, Steinbeis N, & Friederici AD (2017). White matter maturation is associated with the emergence of Theory of Mind in early childhood. Nature communications, 8 PMID: 28322222... Read more »
Grosse Wiesmann C, Schreiber J, Singer T, Steinbeis N, & Friederici AD. (2017) White matter maturation is associated with the emergence of Theory of Mind in early childhood. Nature communications, 14692. PMID: 28322222
There was a time when the neuroscience world was consumed by the question of how individual neurons were coding information about the world. Was it in the average firing rate? Or did every precise spike matter, down to the millisecond? Was … Continue reading →... Read more »
Srivastava KH, Holmes CM, Vellema M, Pack AR, Elemans CP, Nemenman I, & Sober SJ. (2017) Motor control by precisely timed spike patterns. Proceedings of the National Academy of Sciences of the United States of America, 114(5), 1171-1176. PMID: 28100491
Nemenman I, Lewen GD, Bialek W, & de Ruyter van Steveninck RR. (2008) Neural coding of natural stimuli: information at sub-millisecond resolution. PLoS computational biology, 4(3). PMID: 18369423
What IS that? A photo by Stefan Kraft at Wikimedia Commons.1. Platypuses are so strange, that when British scientists first encountered one, they thought it was a joke: A Governor of New South Wales, Australia, sent a platypus pelt and sketch to British scientists in 1798. Even in their first published scientific description of the species, biologists thought that this duck-beaked, beaver-bodied, web-footed specimen may be some Frankenstein-like creation stitched together as a hoax. But this is only the beginning of their oddities…2. Platypuses are egg-laying mammals. Mammals are animals that have a backbone, are warm-blooded, and females produce milk for their young. Most females that nurse their young also carry their developing babies in their bodies and give birth to live young… But platypuses don’t play by those rules. Platypuses are monotremes, egg-laying mammals that include the platypus and four species of echidna. Most female mammals have two functional ovaries, but female platypuses, like most female birds, only have a functional left ovary. Once a year, a female platypus may produce a clutch of two or three small, leathery eggs (similar to reptile eggs), that develop in her uterus for 28 days. Because female platypuses don’t even have a vagina, when the eggs are ready, she lays them through her cloaca, an opening that serves for reproduction, peeing and pooping. (In fact, monotreme comes from the Greek for “one hole”). She then curls around them and incubates them for another 10 days until they hatch. 3. Platypuses sweat milk! Not only do female platypuses not have vaginas, they don’t have nipples either! Instead, lactating mothers ooze milk from pores in their skin, which pools in grooves on their bellies so the babies can lap it up. …And they’re not even embarrassed about it! 4. Adult platypuses are toothless. Baby platypuses (that is the actual technical term for them, by the way… not “puggles”, which would be way more fun) are born with teeth but they lose them around the time that they leave the breeding burrow. In their place are rigid-edged keratinized pads that they use as grinding plates. When they catch their prey (worms, bugs, shrimp, and even crayfish), they store it in their cheek pouches and carry it to the surface, where they use gravel to crush it in their toothless maw.5. The platypus “duck bill” is a sensory organ used to detect electric fields. Muscles and neurons use electrical impulses to function, and these impulses can be detected by electroreceptors. Although common in shark and ray species, electroreception is rare in mammals, only having been discovered in monotremes and the Guiana dolphin. Platypuses have rows of around 40,000 electroreceptors on their highly sensitive bill, which they wave back and forth in the water, much like a hammerhead shark, to determine the location of their prey. It’s a good thing this sense is so sensitive, since they close their eyes, nose and ears every time they dive. 6. Platypuses don’t use their tails like beavers do. Whereas beavers use their large, flat, leathery tails for swimming and slapping the water to send signals, platypuses don’t use their tails for any of that. Platypuses have large, flat tails for storing fat in case of a food shortage. Unlike beaver tails, platypus tails are covered in fur, which the mothers use to snuggle with their incubating eggs.A platypus ankle spur. Photo by E.Lonnon at Wikimedia Commons.7. Male platypuses have venomous ankle spurs. Their venom is strong enough to kill small animals and to create excruciating pain in humans. Since only males have it and they produce more venom during the breeding season, we think its main function may be to compete for mates and breeding territories.8. Platypuses are knuckle-walkers with a reptilian gait. Although they are well-built for swimming with their webbed feet and legs on the sides of their bodies, these traits make it quite awkward to get around on dry land. To walk, they pull in their webbing and walk on their knuckles, exposing their claws. Like reptiles and salamanders, platypuses flex their spines from side-to-side, supported by their sprawling legs. 9. Platypuses have unusually low body temperatures. As unusual as they are, platypuses are still mammals, which are defined, in part, by their ability to generate most of their own body heat with their metabolism. Platypuses do this as well, but whereas most mammals maintain body temperatures between 37-40 degrees C (99-104 degrees F), platypuses are happy with a body temperature of 32 degrees C (90 degrees F). This lower metabolism reduces the amount of calories they need to eat.10. They have no stomach. Stomachs are specialized protein-digesting chambers of digestive tracts that contain protein-digesting enzymes and acids to activate them. Not all animals have them, but most carnivores do. The most common exceptions to this rule are fish… and platypuses. Why? We don’t know for sure, but many of these animals consume diets high in calcium carbonate, which is a natural antacid. If their own diet would constantly neutralize their stomach acid, then the stomach really isn’t going to do them any good anyway.11. They have 10 sex chromosomes! Most mammals have two sex chromosomes, one from each parent. An individual that has two X chromosomes is usually female and an individual that has one X and one Y chromosome is usually male. Thus, female mammals pass along an X chromosome to each offspring and males can pass along an X or a Y. But platypuses are not content to be normal in any way…They have 10 sex chromosomes: 5 from mom and 5 from dad. All 5 chromosomes from mom are Xs, whereas a male sperm either contains 5 Xs or 5 Ys. Birds also have two sex chromosomes, but in birds, individuals with two of the same type are usually male and individuals with different chromosomes are usually female. Their system is called ZW, where the mammalian system is XY. The platypus X chromosome is more similar than the X chromosome of other mammals to the bird Z chromosome.12. The platypus genome is as much of a hodgepodge as its body. Only 80% of the platypus’ genes are like other mammals. Some of their genes have only previously been found in birds, reptiles, fish, or amphibians.To learn about more weird animals, go here.References: ... Read more »
Warren, W., Hillier, L., Marshall Graves, J., Birney, E., Ponting, C., Grützner, F., Belov, K., Miller, W., Clarke, L., Chinwalla, A.... (2008) Genome analysis of the platypus reveals unique signatures of evolution. Nature, 453(7192), 175-183. DOI: 10.1038/nature06936
The evolving epidemic of opioid overdose and overdose deaths is receiving increased public and research attention.Opioids overdoses and overdose deaths are often unintentional or accidental. It has been known that concurrent use of opioids with alcohol or benzodiazepines (i.e. Valium or Xanax) increases risk for overdose toxicity.A recent study published in the British Medical Journal confirmed the association of concurrent benzodiazepine prescription with opioid overdose.This research team examined confidential medical database records from over 500,000 patients in the U.S.Those that were enrolled in a medical plan including pharmaceutical benefits between 2001 and 2013 were included in the analysis.The key findings from the study included the following:The percentage of opioid users concurrently using a benzodiazepine rose from 9% of opioid users in 2001 to 17% of opioid users in 2013Chronic users of opioids nearly doubled their risk of opioid overdose if they took a concurrent benzodiazepine medication (4/100 persons/year to 7-8/100 person years)If the association is causal, the authors estimate emergency room visits and inpatient admissions could be reduced by 15% by stopping concurrent prescriptionsThis association of risk seems reasonable given the toxicities of opioids and benzodiazepines. Both at higher doses decrease respiratory drive potentially contributing to hypoxia and death.The authors note several take home messages for clinicians. Chronic users of benzodiazepines should be prescribed opioids cautiously if at all. Opioid prescriptions should be for short periods of time and low doses for chronic benzodiazepine patients.Likewise, if chronic opioids are necessary they should rarely be combined with intermittent or long-term benzodiazepine prescriptions.Readers with more interest in this topic can access the free full-text manuscript by clicking on the PMID link in the citation below.Photo of NCAA men's basketball tournament in Tulsa, OK is from my files.Follow me on Twitter WRY999Sun EC, Dixit A, Humphreys K, Darnall BD, Baker LC, & Mackey S (2017). Association between concurrent use of prescription opioids and benzodiazepines and overdose: retrospective analysis. BMJ (Clinical research ed.), 356 PMID: 28292769... Read more »
Sun EC, Dixit A, Humphreys K, Darnall BD, Baker LC, & Mackey S. (2017) Association between concurrent use of prescription opioids and benzodiazepines and overdose: retrospective analysis. BMJ (Clinical research ed.). PMID: 28292769
I just read a concerning paper about an experimental stem cell treatment for children with autism.
The authors are Himanshu Bansal and colleagues of India. The senior author, Prasad S Koka, is the Editor-in-Chief of the Journal of Stem Cells where the paper appeared, which raises questions about whether the manuscript received a thorough peer review. Koka is actually an author on all five of the research papers published in that issue of the journal. But that's a minor issue compared ... Read more »
Bansal H, Verma P, Agrawal A, Leon J, Sundell IB, Koka PS. (2016) A Short Study Report on Bone Marrow Aspirate Concentrate Cell Therapy in Ten South Asian Indian Patients with Autism. Journal of Stem Cells, 11(1). info:/
Emotional intelligence (EI) is characterized by the ability to recognize emotional states in self and in others.This emotional recognition may be helpful in guiding behavior and in improving interpersonal relationships.It seems logical on a face validity level to assume that higher levels of EI would be good in the selection of students for medical school.However, there are few studies assessing EI in physicians. There are fewer studies that examine whether EI influences physician behavior, patient satisfaction and ultimately patient outcomes.Rhamzan Shahid and colleagues at the Stritch School of Medicine at Loyola University Medical examined levels of EI in a group of resident physicians in training in the specialties of pediatrics and combined internal medicine-pediatrics.This was a cross-sectional study design that included comparison of residents in the first two years of training versus those in years 3 and 4. The main findings included the following:Residents tended to score high on EI overall with the highest scores on impulse control and the interpersonal composite subscaleResidents scored relatively lower on assertiveness and independence subscalesAssertiveness subscale scores were higher in the more senior residentsEmpathy scores were lower in the the more senior residentsIncreased assertiveness sub-scale scores in more senior residents might be a good thing, possibly indicating a growth in confidence and skill level. This cannot be stated definitely as this study was not longitudinally designed.The lower empathy sub-scale scores in senior residents is an interesting finding. Some might argue it is a negative consequence of training and reflects an increasing disenchantment with being a physician. The authors of the study encourage interventions to "ensure they (resident physicians) do not lose empathy".However, it may be that in a group selected for high empathy, a reduction may also represent a normal maturational process. Maybe high empathy contributes to higher physician distress in the clinical setting and potentially more burnout and depression. Maybe empathy levels that are too high produce emotional states that actually impair physician behavior and reduce effectiveness of clinical decision making.These possibilities should prompt studies correlating EI with patient satisfaction, patient outcome, physician satisfaction with medicine and their specialty and risk for physician burnout.The manuscript reviewed and commented on today is available in free full-text format by clicking on the link in the citation below.Follow me on Twitter @WRY999Photo of the lesser scaup duck is from my personal photography files.Shahid, R., Stirling, J., & Adams, W. (2016). Assessment of Emotional Intelligence in Pediatric and Med-Peds Residents Journal of Contemporary Medical Education, 4 (4) DOI: 10.5455/jcme.20170116015415... Read more »
Shahid, R., Stirling, J., & Adams, W. (2016) Assessment of Emotional Intelligence in Pediatric and Med-Peds Residents. Journal of Contemporary Medical Education, 4(4), 153. DOI: 10.5455/jcme.20170116015415
How much damage can the brain take and still function normally? In a new paper, A Lesion-Proof Brain?, Argentinian researchers Adolfo M. García et al. describe the striking case of a woman who shows no apparent deficits despite widespread brain damage.
The patient, "CG", is 44 years old and was previously healthy until a series of strokes lesioned large parts of her brain, as shown below.
García et al. say that the damage included "extensive compromise of the right fronto-temporo-parie... Read more »
García, A., Sedeño, L., Herrera Murcia, E., Couto, B., & Ibáñez, A. (2017) A Lesion-Proof Brain? Multidimensional Sensorimotor, Cognitive, and Socio-Affective Preservation Despite Extensive Damage in a Stroke Patient. Frontiers in Aging Neuroscience. DOI: 10.3389/fnagi.2016.00335
Amyloid brain plaques are well-known pathological changes associated with Alzheimer's disease. Changes preceding amyloid plaque build up are less well studied and understood. Some of this relates to limitations to current imaging technology.Klementieva and colleagues from Sweden and Spain recently published an important reserach topic in this area.Their studied used a rat model of Alzheimer's disease and imaging techniques that included infrared microspectroscopy and gel electrophoresis.The main findings of their study included the following:Conformation changes of beta amyloid and it's amyloid precursor protein (APP) start before the development of amyloid plaquesThe early changes in beta amyloid localize to the synaptic terminalsThese early changes may provide novel targets for drug developmentThese findings suggest current strategies to alter beta amyloid plaques after development may be too late to alter the course of the disease.Identification and reversal of earlier mechanisms may be a more productive drug development strategy.Readers with more interest in this topic can access the free full-text manuscript by clicking on the citation link below.Follow be on Twitter WRY999Photo of robin in back yard waterer is from my photography files.Klementieva, O., Willén, K., Martinsson, I., Israelsson, B., Engdahl, A., Cladera, J., Uvdal, P., & Gouras, G. (2017). Pre-plaque conformational changes in Alzheimer’s disease-linked Aβ and APP Nature Communications, 8 DOI: 10.1038/ncomms14726... Read more »
Klementieva, O., Willén, K., Martinsson, I., Israelsson, B., Engdahl, A., Cladera, J., Uvdal, P., & Gouras, G. (2017) Pre-plaque conformational changes in Alzheimer’s disease-linked Aβ and APP. Nature Communications, 14726. DOI: 10.1038/ncomms14726
Older drivers are over-represented in motor-vehicle driving accidents.The lowest rate of fatal vehicle crashes per 100 million miles driven is found in drivers between the ages of 30-69 years of age.Fatal vehicle driving rates per miles driven is 4 to 5 times higher in drivers over 80 years of age. (IIHS.org data)So can older drivers be trained or educated to improve their safety (and the safety o those around them)?A recent randomized controlled trial examined an educational intervention in drivers 75 years and older in Australia.This intervention targeted a reduction or avoidance of seven high-risk driving situations:Night drivingDriving in the rainRight-hand (left-hand in U.S.) turns across oncoming trafficDriving during heavy trafficDriving on high-speed roadsDriving during rush hourDriving aloneThe trial found participants in the intervention group showed a greater readiness to make changes that could reduce high-risk accident exposure. However, the intervention group did not reduce total miles driven in the year following the intervention.Additionally, the intervention group did not increase their use of alternate transportation (i.e. buses or cabs) in the follow-up period.This trial showed limited response to educational training in an older-aged drivers population. Alternate approaches (adoption of high safety feature vehicles, use of newer alternative driving programs like Uber, cognitive training programs to improve psychomotor speed) may hold more promise in reducing fatal accident rates in elderly populations.Follow me on Twitter WRY999Photo of moon is from my photography files.Coxon K, Chevalier A, Brown J, Clarke E, Billot L, Boufous S, Ivers R, & Keay L (2016). Effects of a Safe Transportation Educational Program for Older Drivers on Driving Exposure and Community Participation: A Randomized Controlled Trial. Journal of the American Geriatrics Society PMID: 27943260... Read more »
Coxon K, Chevalier A, Brown J, Clarke E, Billot L, Boufous S, Ivers R, & Keay L. (2016) Effects of a Safe Transportation Educational Program for Older Drivers on Driving Exposure and Community Participation: A Randomized Controlled Trial. Journal of the American Geriatrics Society. PMID: 27943260
Fig 1 (Roskams-Edriset al., 2017). The number of patents implicating specific brain regions has risen from 1976 to the mid 2010s. Results were obtained by searching The Lens patent database (http://lens.org/).
“What is the ethical value of awarding patent rights that implicate regions of the brain?”
Do the applicants intend to patent the function of specific brain areas? This absurd
... Read more »
Roskams-Edris, D., Anderson-Redick, S., Kiss, Z., & Illes, J. (2017) Situating brain regions among patent rights and moral risks. Nature Biotechnology, 35(2), 119-121. DOI: 10.1038/nbt.3782
Imagine there is a cookie sitting in front of you. You are hungry. You have been on a diet for months. If you have to look at one more raw, paleo, gluten free snack you are going to scream.... Read more »
Lehne, M., & Koelsch, S. (2015) Toward a general psychological model of tension and suspense. Frontiers in Psychology. DOI: 10.3389/fpsyg.2015.00079
Naqvi, N., Gaznick, N., Tranel, D., & Bechara, A. (2014) The insula: A critical neural substrate for craving and drug seeking under conflict and risk. Annals of the New York Academy of Sciences, 53-70. PMID: 24690001
Saarikallio, S., Nieminen, S., & Brattico, E. (2012) Affective reactions to musical stimuli reflect emotional use of music in everyday life. Musicae Scientiae, 17(1), 27-39. DOI: 10.1177/1029864912462381
What happens in the brain when we die?
Canadian researchers Loretta Norton and colleagues of the University of Western Ontario examine this grave question in a new paper: Electroencephalographic Recordings During Withdrawal of Life-Sustaining Therapy Until 30 Minutes After Declaration of Death
Norton et al. examined frontal EEG recordings from four critically ill patients at the point where their life support was withdrawn. Here are some details on the four:
Here's the EEG recor... Read more »
Norton L, Gibson RM, Gofton T, Benson C, Dhanani S, Shemie SD, Hornby L, Ward R, & Young GB. (2017) Electroencephalographic Recordings During Withdrawal of Life-Sustaining Therapy Until 30 Minutes After Declaration of Death. The Canadian Journal of Neurological Sciences, 44(2), 139-145. PMID: 28231862
There are significant barriers to widespread use of hearing-aids in older adults with age-related hearing loss.Sensitivity to the stigma of wearing a hearing-aid is one barrier.Cost is another significant barrier. In the U.S., bilateral hearing-aid purchase amounts to a cost of $2400 to $5800. This cost is typically not covered by Medicare or other health insurance plans.I ran into a interesting manuscript on looking at an alternative less costlier approach to hearing-aid selection and purchase.Larry Humes and colleagues compared the outcome of a older adults randomized to one of three hearing aid interventions. One was standard audiology best practices, one was a placebo hearing-aid (device without amplication). A third alternative was also studied that was called an over-the-counter (OTC) intervention. This intervention included the following elements:Self-selection of hearing aid tips, tubes and devicesThree types of hearing-aids were provided for selection. Each was programmed with one of the three most common patterns of hearing lossSubjects tried various combinations of devices and listened to sample sounds of speech, music and environmental soundsSubjects were assessed after a six week trial for hearing function, satisfaction and desire to keep the deviceSubjects were randomized to pay a fee of $3500 versus $600 for devices that were identical in features. This allowed for study of the effect of cost on outcome measures.Interestingly, the OTC intervention resulted in outcomes (i.e. hearing improvement) that were very similar to audiology best practices. However, OTC subjects showed a slightly lower satisfaction score and were somewhat more likely to return devices after the study for a refund. Higher price also predicted return for refund following the study.The authors conclude:"Efficacious OTC service-delivery models (and devices) may increase accessibility and affordability of hearing aids for millions of older adults, but further research is required to evaluate various devices and approaches as well as to examine the generalization of the findings from this clinical trial."This study provides an impetus for further study of the OTC model in hearing aid selection and use. Cost issues appear to continue to be a significant barrier to wider hearing-aid access.Readers with more interest in this study can access the free full-text manuscript by clicking on the link in the citation below.Photo of wood duck is from my photography file.Follow me on Twitter WRY999Humes, L., Rogers, S., Quigley, T., Main, A., Kinney, D., & Herring, C. (2017). The Effects of Service-Delivery Model and Purchase Price on Hearing-Aid Outcomes in Older Adults: A Randomized Double-Blind Placebo-Controlled Clinical Trial American Journal of Audiology DOI: 10.1044/2017_AJA-16-0111... Read more »
Humes, L., Rogers, S., Quigley, T., Main, A., Kinney, D., & Herring, C. (2017) The Effects of Service-Delivery Model and Purchase Price on Hearing-Aid Outcomes in Older Adults: A Randomized Double-Blind Placebo-Controlled Clinical Trial. American Journal of Audiology, 1. DOI: 10.1044/2017_AJA-16-0111
Neurofeedback training (NFT) is a procedure that tries to shape a participant's pattern of brain activity by providing real-time feedback, often in the form of a video game combined with other sensory stimuli that provide rewards when the “correct” state is achieved. The most common form of NFT uses EEG (brainwave) activity recorded non-invasively from the scalp. The EEG is a complex mixture
... Read more »
Manuel Schabus, Hermann Griessenberger, Maria-Teresa Gnjezda, Dominik P.J. Heib, Malgorzata Wislowska, Kerstin Hoedlmoser. (2017) Better than sham? A double-blind placebo-controlled neurofeedback study in primary insomnia. Brain. info:/10.1093/brain/awx011
Sitaram, R., Ros, T., Stoeckel, L., Haller, S., Scharnowski, F., Lewis-Peacock, J., Weiskopf, N., Blefari, M., Rana, M., Oblak, E.... (2016) Closed-loop brain training: the science of neurofeedback. Nature Reviews Neuroscience, 18(2), 86-100. DOI: 10.1038/nrn.2016.164
Despite centuries of experience in education, the best time to start formal education is still under debate. Is five years of age too old? Is three years of age too early?One issue with early education interventions is the potential for catch-up in children starting school later. In other words, early gains with younger children may evaporate overtime.One recent research study examines effectiveness of a child development intervention known as Educare. Educare seeks to reduce the achievement gap between low-income and economically advantaged peer children.Educare is operational in 21 cities in the United States. It is somewhat unique in entering children as infants (<1 year of age) for an intensive ongoing child and parent intervention. A recent study randomized 239 infants to receive Educare or no intervention. This study found superiority for the Educare children following one-year of intervention in the following domains:Expressive communicationAuditory comprehensionProblem behaviors (reduced level)Positive parental-child interactionThe authors note the size of the effects were in the modest to medium strength. Additionally, they note they cannot know how enduring the effects of this type of intervention might be.Additional longitudinal assessments will be needed to examine the potential of catch up in the control group. Studies of elementary, middle and senior high achievement will be needed.Aggressive early intervention programs are expensive and will need to be validated before efforts to expand this type of early childhood intervention.Follow me on Twitter WRY999Photo of children playing on the beach at sunset is from my photography files.Yazejian, N., Bryant, D., Hans, S., Horm, D., St. Clair, L., File, N., & Burchinal, M. (2017). Child and Parenting Outcomes After 1 Year of Educare Child Development DOI: 10.1111/cdev.12688... Read more »
Yazejian, N., Bryant, D., Hans, S., Horm, D., St. Clair, L., File, N., & Burchinal, M. (2017) Child and Parenting Outcomes After 1 Year of Educare. Child Development. DOI: 10.1111/cdev.12688
Where are the mammillary bodies?
The mammillary bodies are part of the diencephalon, which is a collection of structures found between the brainstem and cerebrum. The diencephalon includes the hypothalamus, and the mammillary bodies are found on the inferior surface of the hypothalamus (the side of the hypothalamus that is closer to the brainstem). The mammillary bodies are a paired structure, meaning there are two mammillary bodies---one on either side of the midline of the brain. They get their name because they were thought by early anatomists to have a breast-like shape. The mammillary bodies themselves are sometimes each divided into two nuclei, the lateral and medial mammillary nuclei. The medial mammillary nucleus is the much larger of the two, and is often subdivided into several subregions. What are the mammillary bodies and what do they do?The mammillary bodies are best known for their role in memory, although in the last couple of decades the mammillary bodies have started to be recognized as being involved in other functions like maintaining a sense of direction. The role of the mammillary bodies in memory has been acknowledged since the late 1800s, when mammillary body atrophy was observed in Korsakov's syndrome---a disorder characterized by amnesia and usually linked to a thiamine deficiency. Since then a number of findings---anatomical, clinical, and experimental---have supported and expanded upon a mnemonic role for the mammillary bodies.The mammillary bodies are directly connected to three other brain regions: the hippocampus via the fornix, thalamus (primarily the anterior thalamic nuclei) via the mammillothalamic tract, and the tegmental nuclei of the midbrain via the mammillary peduncle and mammillotegmental tract. Two of the three connections are thought to primarily carry information in one direction: the hippocampal connections carry information from the hippocampus to the mammillary bodies and the thalamic connections carry information from the mammillary bodies to the thalamus (the tegmental connections are reciprocal). These connections earned the mammillary bodies the reputation of being relay nuclei that pass information from the hippocampus on to the anterior thalamic nuclei to aid in memory consolidation. This hypothesis is supported by the fact that damage to pathways that connect the mammillary bodies to the hippocampus or thalamus is associated with deficits in consolidating new memories. Others argue, however, that the mammillary bodies act as more than a simple relay, making independent contributions to memory consolidation. Both perspectives emphasize a role for the mammillary bodies in memory but differ as to the specifics of that role.Further supporting a role for the mammillary bodies in memory, there is evidence from humans that suggests damage to the mammillary bodies is associated with memory deficits. Several cases of brain damage involving the mammillary bodies as well as cases of tumor-related damage to the area of the mammillary bodies suggests that damage to the mammillary bodies is linked to anterograde amnesia. Indeed, mammillary body dysfunction has been identified as a major factor in diencephalic amnesia, a type of amnesia that originates in the diencephalon (Korsakoff's syndrome, an amnesia that is seen primarily in long-term alcoholics, is one type of diencephalic amnesia).Experimental evidence from animal studies also underscores the importance of the mammillary bodies in memory. Studies with rodents and monkeys have found deficits in spatial memory to occur after damage to the mammillary bodies or the mammillothalamic tract. In addition to involvement in memory functions, there are cells in the mammillary bodies that are activated only when an animal's head is facing in a particular direction. These cells are thought to be involved in navigation and may act somewhat like a compass in creating a sense of direction.Vann SD, & Aggleton JP (2004). The mammillary bodies: two memory systems in one? Nature reviews. Neuroscience, 5 (1), 35-44 PMID: 14708002... Read more »
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