Breaking News
May 3, 2019 - Vaping and Smoking May Signal Greater Motivation to Quit
May 3, 2019 - Dementia looks different in brains of Hispanics
May 3, 2019 - Short-Staffed Nursing Homes See Drop In Medicare Ratings
May 3, 2019 - Study of teens with eating disorders explores how substance users differ from non-substance users
May 3, 2019 - Scientists develop new video game that may help in the study of Alzheimer’s
May 3, 2019 - Arc Bio introduces Galileo Pathogen Solution product line at ASM Clinical Virology Symposium
May 3, 2019 - Cornell University study uncovers relationship between starch digestion gene and gut bacteria
May 3, 2019 - How to Safely Use Glucose Meters and Test Strips for Diabetes
May 3, 2019 - Anti-inflammatory drugs ineffective for prevention of Alzheimer’s disease
May 3, 2019 - Study tracks Pennsylvania’s oil and gas waste-disposal practices
May 3, 2019 - Creating a better radiation diagnostic test for astronauts
May 3, 2019 - Vegans are often deficient in these four nutrients
May 3, 2019 - PPDC announces seed grants to develop medical devices for children
May 3, 2019 - Study maps out the frequency and impact of water polo head injuries
May 3, 2019 - Research on Reddit identifies risks associated with unproven treatments for opioid addiction
May 3, 2019 - Good smells may help ease tobacco cravings
May 3, 2019 - Medical financial hardship found to be very common among people in the United States
May 3, 2019 - Researchers develop multimodal system for personalized post-stroke rehabilitation
May 3, 2019 - Study shows significant mortality benefit with CABG over percutaneous coronary intervention
May 3, 2019 - Will gene-editing of human embryos ever be justifiable?
May 3, 2019 - FDA Approves Dengvaxia (dengue vaccine) for the Prevention of Dengue Disease in Endemic Regions
May 3, 2019 - Why Tonsillitis Keeps Coming Back
May 3, 2019 - Fighting the opioid epidemic with data
May 3, 2019 - Maggot sausages may soon be a reality
May 3, 2019 - Deletion of ATDC gene prevents development of pancreatic cancer in mice
May 2, 2019 - Targeted Therapy Promising for Rare Hematologic Cancer
May 2, 2019 - Alzheimer’s disease is a ‘double-prion disorder,’ study shows
May 2, 2019 - Reservoir bugs: How one bacterial menace makes its home in the human stomach
May 2, 2019 - Clinical, Admin Staff From Cardiology Get Sneak Peek at Epic
May 2, 2019 - Depression increases hospital use and mortality in children
May 2, 2019 - Vicon and NOC support CURE International to create first gait lab in Ethiopia
May 2, 2019 - Researchers use 3D printer to make paper organs
May 2, 2019 - Viral infection in utero associated with behavioral abnormalities in offspring
May 2, 2019 - U.S. Teen Opioid Deaths Soaring
May 2, 2019 - Opioid distribution data should be public
May 2, 2019 - In the Spotlight: “I’m learning every single day”
May 2, 2019 - 2019 Schaefer Scholars Announced
May 2, 2019 - Podcast: KHN’s ‘What The Health?’ Bye-Bye, ACA, And Hello ‘Medicare-For-All’?
May 2, 2019 - Study describes new viral molecular evasion mechanism used by cytomegalovirus
May 2, 2019 - SLU study suggests a more equitable way for Medicare reimbursement
May 2, 2019 - Scientists discover first gene involved in lower urinary tract obstruction
May 2, 2019 - Researchers identify 34 genes associated with increased risk of ovarian cancer
May 2, 2019 - Many low-income infants receive formula in the first few days of life, finds study
May 2, 2019 - Global study finds high success rate for hip and knee replacements
May 2, 2019 - Taking depression seriously: What is it?
May 2, 2019 - With Head Injuries Mounting, Will Cities Put Their Feet Down On E-Scooters?
May 2, 2019 - Scientists develop small fluorophores for tracking metabolites in living cells
May 2, 2019 - Study casts new light into how mothers’ and babies’ genes influence birth weight
May 2, 2019 - Researchers uncover new brain mechanisms regulating body weight
May 2, 2019 - Organ-on-chip systems offered to Asia-Pacific regions by Sydney’s AXT
May 2, 2019 - Adoption of new rules drops readmission penalties against safety net hospitals
May 2, 2019 - Kids and teens who consume zero-calorie sweetened beverages do not save calories
May 2, 2019 - Improved procedure for cancer-related erectile dysfunction
May 2, 2019 - Hormone may improve social behavior in autism
May 2, 2019 - Alzheimer’s disease may be caused by infectious proteins called prions
May 2, 2019 - Even Doctors Can’t Navigate Our ‘Broken Health Care System’
May 2, 2019 - Study looks at the impact on criminal persistence of head injuries
May 2, 2019 - Honey ‘as high in sugars as table sugar’
May 2, 2019 - Innovations to U.S. food system could help consumers in choosing healthy foods
May 2, 2019 - FDA Approves Mavyret (glecaprevir and pibrentasvir) as First Treatment for All Genotypes of Hepatitis C in Pediatric Patients
May 2, 2019 - Women underreport prevalence and intensity of their own snoring
May 2, 2019 - Concussion summit focuses on science behind brain injury
May 2, 2019 - Booker’s Argument For Environmental Justice Stays Within The Lines
May 2, 2019 - Cornell research explains increased metastatic cancer risk in diabetics
May 2, 2019 - Mount Sinai study provides fresh insights into cellular pathways that cause cancer
May 2, 2019 - Researchers to study link between prenatal pesticide exposures and childhood ADHD
May 2, 2019 - CoGEN Congress 2019: Speakers’ overviews
May 2, 2019 - A new strategy for managing diabetic macular edema in people with good vision
May 2, 2019 - Sagent Pharmaceuticals Issues Voluntary Nationwide Recall of Ketorolac Tromethamine Injection, USP, 60mg/2mL (30mg per mL) Due to Lack of Sterility Assurance
May 2, 2019 - Screen time associated with behavioral problems in preschoolers
May 2, 2019 - Hormone reduces social impairment in kids with autism | News Center
May 2, 2019 - Researchers synthesize peroxidase-mimicking nanozyme with low cost and superior catalytic activity
May 2, 2019 - Study results of a potential drug to treat Type 2 diabetes in children announced
May 2, 2019 - Multigene test helps doctors to make effective treatment decisions for breast cancer patients
May 2, 2019 - UNC School of Medicine initiative providing unique care to dementia patients
May 2, 2019 - Nestlé Health Science and VHP join forces to launch innovative COPES program for cancer patients
May 2, 2019 - Study examines how our brain generates consciousness and loses it during anesthesia
May 2, 2019 - Transition Support Program May Aid Young Adults With Type 1 Diabetes
May 2, 2019 - Study shows how neutrophils exacerbate atherosclerosis by inducing smooth muscle-cell death
May 2, 2019 - Research reveals complexity of how we make decisions
Special input pathway may hold the key to coding sensory information in the cerebellum

Special input pathway may hold the key to coding sensory information in the cerebellum

As we go about our daily lives, we are constantly bombarded by a steady stream of sensory information. Take a typical morning routine for example- roused from sleep by a shrill alarm, the strong aroma of freshly brewed coffee, and the brake lights and traffic horns of rush hour. In the course of a single day, we experience thousands of different cues across all senses.

Despite the numerous chaotic cues we encounter, our brains do a remarkable job assembling and processing them; allowing us to make sense of the world around us. This processing can take shape in very noticeable ways, such as our vision and hearing, but also occurs more subtly and unexpectedly. For instance, when learning a new movement, our brain is constantly keeping track of the sensory cues around us. This sensory snapshot helps to instruct and guide motor learning so that when we encounter the same context again, we’ll be more likely to perform the movement in better way.

Though there is a wealth knowledge supporting the idea that sensory cues benefit motor learning, the precise brain circuitry and mechanisms tying these two together has been debated in recent years. Shedding new light on this topic, a recently published paper in Neuron from the lab of Dr. Jason Christie, Research Group Leader at the Max Planck Florida Institute for Neuroscience (MPFI), has revealed that a special input pathway into the cerebellum seems to hold the key to coding sensory information.

The cerebellum is a unique structure within the brain that plays a critically important role in motor coordination and learning that improves movements. By receiving many inputs from various regions of the brain, the cerebellum integrates and sends refined information out through a single neuron type called a Purkinje cell. One significant input to the Purkinje cells, are long-range projections called climbing fibers.

“Climbing fibers are very well-known and extensively studied in the field.” describes Dr. Michael Gaffield, Research Fellow in the Christie Lab and first author of the publication. “These fibers form long-range connections with the cerebellum and are thought to deliver instructive motor signals and relay sensory information. But in the past few years it’s been suggested that local circuits within the cerebellum, such as parallel fibers or molecular layer interneurons, may also play a part in coding of sensory information.”

To investigate, the team used two-photon calcium imaging to monitor the activity of Purkinje cells within the cerebellum of mice while presenting various sensory stimuli (auditory, visual and somatosensory). They then isolated and assessed changes in Purkinje cell activity that directly corresponded to the timing of each individual stimulus and climbing fiber input.

“Within each Purkinje cell, we saw a consistent enhancement of activity whenever a sensory stimulus was presented. But the enhancement wasn’t the exact same across all three sensory types, it varied depending on the type of stimulus presented” explains Gaffield.

Next MPFI scientists examined if other cell types besides climbing fibers, contributed directly to the sensory enhanced activity seen in the Purkinje cells. Using the techniques of optogenetic inactivation (suppression of neural activity using light) and chemogenetic inhibition (suppression of neural activity using drugs), the team was able to inhibit individual cell types in the local cerebellar circuitry. Despite altering the local activity, no change occurred to the sensory enhanced activity of the Purkinje cells. However, by inhibiting climbing fiber activity directly, the enhancement was abolished; indicating that climbing fibers alone are responsible for conveying sensory information to the cerebellum.

Taking their investigation a step further, the Christie lab pioneered a novel technique allowing them to monitor the activity of climbing fiber axonal projections themselves. They discovered that when presenting sensory stimuli, the graded changes in the presynaptic activity of climbing fibers was accurately represented in the Purkinje cells; stronger activity in the climbing fiber was precisely mirrored by stronger activity in the Purkinje cells they connect with.

“Our results actually came as a bit of a surprise” notes Dr. Christie. “Traditionally it was thought that sensory signals arriving in the cerebellum were integrated and processed by Purkinje cells using local connections. Our findings demonstrate that Purkinje cells are merely reflecting what the climbing is doing. This means that a more distal region of the brain is doing the actual processing of sensory information and simply relaying it to the cerebellum. “

“Since Purkinje cell activity is critically important for motor learning, we are now in the process looking at sensory-derived activity during more complex motor behaviors” describes Dr. Christie. “Hopefully we will be able to uncover the neural mechanisms that underlie the climbing fiber’s unique ability to convey sensory information and how learning benefits from this coding scheme.”

About author

Related Articles