Breaking News
September 22, 2018 - Concern over fussy eating prompts parents to use non-responsive feeding practices
September 22, 2018 - Novel mathematical approach uncovers existence of unsuspected biological cycles
September 22, 2018 - Cancer Research UK invests £14 million to transform London into cancer biotherapeutics hub
September 22, 2018 - Scientists predict how well the body will fight lung cancer by analyzing immune cell shapes
September 22, 2018 - New outbreak of rare eye disease identified in contact lens wearers
September 22, 2018 - Iterum Initiates SURE 2 and SURE 3 Phase 3 Clinical Trials of IV and Oral Sulopenem in Complicated Urinary Tract and Complicated Intra-abdominal Infections
September 22, 2018 - Research finds divide in dental health accessibility between city and regional areas
September 22, 2018 - Premature babies show better brain development when fed breast milk, finds study
September 22, 2018 - Novel system uses AI to detect abnormalities in fetal hearts
September 22, 2018 - UNC scientists reveal new approach to prevent obesity and diabetes
September 22, 2018 - CWRU receives NIH grant to learn how non-coding genes contribute to spread of colorectal cancer
September 22, 2018 - Scientists better understand influenza virus and how it spreads
September 22, 2018 - Scientists to focus on length of time when a person is alive and healthy
September 22, 2018 - Study shows positive financial impacts of Medicaid expansion for low-income Michigan residents
September 22, 2018 - Innovative approach for developing vaccine against most prevalent human malaria parasite
September 22, 2018 - Inhibiting NF-kB improves heart function in a mouse model of Duchenne muscular dystrophy
September 22, 2018 - Introducing new EMR system may affect several aspects of clinic workflow
September 22, 2018 - Study finds why some human genes are more popular with biomedical researchers
September 22, 2018 - Finding epigenetic signature appears to predict inflammation risk in serious type of IBD
September 22, 2018 - Researchers develop light-based technique to measure very weak magnetic fields
September 22, 2018 - UAB researchers study dysfunction of the immune system associated with NSAID carprofen
September 22, 2018 - QIAGEN and DiaSorin launch automated, CE-marked workflow for high-throughput TB screening
September 22, 2018 - Researchers identify new genetic disorder in a human patient
September 22, 2018 - Cardiac MR With Contrast Feasible in Developing World
September 22, 2018 - Daily low-dose aspirin doesn’t reduce heart-attack risk in healthy people
September 21, 2018 - Children with asthma found to be disadvantaged in education and future occupation
September 21, 2018 - Interaction of chemical slurry and ancient shale in fracking wastewater causes radioactivity
September 21, 2018 - Scientists use mice to study transmission of Lyme disease bacteria by infected ticks
September 21, 2018 - Researchers find that sample size is key factor determining accuracy of study results
September 21, 2018 - Study shows how the drive to eat overpowers the brain’s signal to stop
September 21, 2018 - 30 Million Americans Now Have Diabetes
September 21, 2018 - Thousands of breast cancer gene variants engineered and analyzed
September 21, 2018 - The current fellowship interview process is cumbersome — Stanford researchers have a better idea
September 21, 2018 - Progenitor cells for human bone and cartilage have been identified
September 21, 2018 - Study reveals new therapeutic target for pediatric tumor-associated intractable epilepsy
September 21, 2018 - SLU’s College professor receives NIH grant to develop I-TEST project
September 21, 2018 - DermTech completes enrollment in clinical study to assess DNA damage and reversal
September 21, 2018 - Grieving patients treated with talk therapy have lower risk of suicide and psychiatric illness
September 21, 2018 - NIH and FDA call for eliminating involvement of RAC in human gene therapy experiments
September 21, 2018 - New system uses algorithm to convert 2D videos into 3D printed ‘motion sculptures’
September 21, 2018 - Sea squirt model reveals key molecules in dopaminergic neuron differentiation
September 21, 2018 - Effective management of neonatal abstinence syndrome requires coordinated ‘cascade of care’
September 21, 2018 - Refugees seek care for wounds of war
September 21, 2018 - Under the sea, in an octopus’ garden on ecstacy
September 21, 2018 - Eating foods with low nutritional quality ratings linked to cancer risk in large European cohort
September 21, 2018 - Giving kids honest information about water consumption may help them make healthy choices
September 21, 2018 - Horwitz Prize Awarded for Work on Hormones
September 21, 2018 - CHMP issues positive opinion supporting use of Trelegy Ellipta in broader group of COPD patients
September 21, 2018 - Scientists discover new molecules that work together to remove unwanted DNA
September 21, 2018 - Dr. Fenella France to deliver 2019 Plenary Lecture
September 21, 2018 - New research finds that MHC-II molecules have more influence on tumors than MHC-I
September 21, 2018 - Researchers study effects of cardiac cycle in simple learning task
September 21, 2018 - FDA takes new steps to address opioid crisis by approving Opioid Analgesic Risk Evaluation and Mitigation Strategy
September 21, 2018 - Positive Barhemsys Phase 3 Treatment Data Published in Anesthesia & Analgesia
September 21, 2018 - Celiac Disease Screening: MedlinePlus Lab Test Information
September 21, 2018 - Autism linked to egg cells’ difficulty creating large proteins
September 21, 2018 - Tweaking nuclear pores could provide new avenue to battle against cancer
September 21, 2018 - Experts warn health care providers to slow down in allowing smart pill in patient care settings
September 21, 2018 - MoreGrasp reports breakthrough development of grasp neuroprosthetics activated by thought control
September 21, 2018 - Study reveals new way to target HER2-negative metastatic breast cancer
September 21, 2018 - CHMP grants positive opinion for VENCLYXTO plus rituximab for treating relapsed/refractory CLL
September 21, 2018 - Study offers solid link between visceral organs and brain’s reward, motivation system
September 21, 2018 - First U.S. patient treated with innovative gene therapy at Bascom Palmer Eye Institute
September 21, 2018 - New study shows how Ethiopia has managed to achieve extraordinary progress
September 21, 2018 - Choroidal Detachment – The American Society of Retina Specialists
September 21, 2018 - New clinical trial evaluates aesthetic results of conservative surgery in breast cancer
September 21, 2018 - Discovery of a key protein involved in the development of autism
September 21, 2018 - Air pollution appears to be linked to increased risk of developing dementia
September 21, 2018 - Henry Ford Health System receives $600k grant to study genetic makeup of gliomas
September 21, 2018 - Arthritis common in individuals with varying degrees of depression, finds study
September 21, 2018 - Scientist intends to fight pathogenic bacteria with viruses
September 21, 2018 - New research suggests link between PFAS chemicals and hyperthyroidism in pet cats
September 21, 2018 - Multi-year study data shows impact of new soft contact lens to slow myopia progression in children
September 21, 2018 - Neuroscientists identify circuit for brain’s statistical inference about motion
September 21, 2018 - MILabs’ VECTor6 system wins Commercial Innovation Award at WMIC 2018
September 21, 2018 - Scientists find wild African monkeys infected with bacterium that causes syphilis, yaws in humans
September 21, 2018 - 2006 to 2015 Saw Increase in Severe Maternal Morbidity
September 21, 2018 - Similar changes in the brains of patients with ADHD and emotional instability
September 21, 2018 - Cobalt mining in DR Congo takes a high toll on both creuseurs and environment
September 21, 2018 - Eating fatty fish during pregnancy may boost unborn child’s brain development
Comparative silence between firing spikes of neurons reveals what they are really up to

Comparative silence between firing spikes of neurons reveals what they are really up to

image_pdfDownload PDFimage_print

It’s the comparative silence between the firing spikes of neurons that tells what they are really up to, scientists report.

“The brain appears to use these durations of silence to encrypt information,” Dr. Joe Z. Tsien, neuroscientist at the Medical College of Georgia at Augusta University says of his new Neural Self-Information Theory.

It’s widely held that neurons generate perceptions, thoughts and actions by emitting electrical pulses called action potentials or spikes. One problem with that standard measure of neuron action is that neurons are essentially always firing at some level and with spontaneous fluctuation, even when it’s not clear what is happening as a result, says Tsien, Georgia Research Alliance Eminent Scholar in Cognitive and Systems Neurobiology and a corresponding author of the study in the journal Cerebral Cortex.

He uses the analogy of an ocean surface that may look calm compared to a tsunami, but is never truly still. Many scientists have noted that there can also be variation in how even the same neuron responds to the same stimulus or even a quiet, resting state. Yet, there must be some kind of operating principle that enables us to think and act in real time in the face of this ongoing variability, he says. Brain scientists call the decades-old puzzle cracking the neural code.

Tsien’s team has evidence from monitoring mouse neurons during various activities that the magic happens when you see a group of neurons each entering an atypical state for them – not of firing – but of the relative periods of silence between the firing and entering that period at the same time.

These silent spaces between overt firing are called interspike intervals, and, the neurons having atypical intervals at the same time are part of a clique generating perceptions, actions and thoughts in real time, he theorizes.

“These cells belong to the same group, an assembly,” Tsien says. “It’s a very general finding about how neuron activity codes information.”

Applying this new Neural Self-Information Theory, they have identified 15 groups of cell assemblies in the cortex and hippocampus of the brain that work together to enable things like sleep cycles, sensing where you are and how you act in response to things you see and experience.

For example, they studied mice playing a game where a light shines on a wall and the mouse learns that if he pokes a hole in that same spot, rather than four other choices, he will get a food pellet when he returns to where he started. If he doesn’t come back in time or pokes the wrong hole, no food pellet awaits. “It’s a simple task but highly attention driven, and how the brain executes this task was poorly understood,” Tsien says.

“To identify the cell cliques that help the mouse be successful, you have to find out what each neuron’s interspike intervals looks like when they are out of their normal range of occurrence,” Tsien says. “Among all the cells you record, you then identify the ones that move into that different state – called a surprisal state – at the same time.” This time he uses the analogy of a normally chatty individual in an uncharacteristic period of silence.

“That is when these cells start to act as a clique,” he says. “That is when the neural cliques are coming together to encode a train of thought or a set of actions. If it’s what happens usually, that means it does not carry much information, it’s like a ground state,” Tsien adds.

Tagged with:

About author

Related Articles