• Study Resource
  • Explore Categories
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
Membrane potential moves toward the K equilibrium
Membrane potential moves toward the K equilibrium

... Resting membrane potential - e.m.f. (voltage) between the inside and outside of a cell: •The zero reference point is outside the cell. •The inside of the cell is negative compared to the ref. •All cells have a membrane potential •In excitable cells (neurons and muscle cells) it is particularly impor ...
Neurophysiology Neurotransmitter and Nervous System
Neurophysiology Neurotransmitter and Nervous System

... the Na+ ion channels close and the K+ channels open and the K+ ions are driven out of the cell because of their concentration gradient and electrostatic charge. ...
2.2 Electrical Communication Study Guide by Hisrich
2.2 Electrical Communication Study Guide by Hisrich

... Eventually the lung muscles cannot contract, causing death. ...
The Nervous System
The Nervous System

... In all exercises, quizzes and tests in this class, always answer in your own words. That is the only way that you can show that you understand what you are saying. Also, make it a habit to answer in full sentences whenever it is appropriate for the question. You will also be responsible for the voca ...
Nervous System
Nervous System

... • Caffeine – lowers threshold at synapses so neurons are more easily excited. • Zoloft/Prozac/Paxil– keeps serotonin in the synapse longer; anti-depressants • Dilantin – increasing effectiveness of ...
PPt #2 Human Body Nervous system
PPt #2 Human Body Nervous system

... • 3. I can compare and contrast the central and peripheral nervous systems • 4. I can identify and explain different areas of the brain and their functions. • 5. I can explain how the nervous system passes information between the external environment and the many parts of the body. ...
Exam 4 Review Exercise 11
Exam 4 Review Exercise 11

... Exercise 13 Be able to identify the lobes, sulci, and fissures of the cerebrum. Fig. 13.8A Be able to identify the thalamus, hypothalamus, pituitary gland, pineal gland, corpus collosum, midbrain, pons, medulla oblongata, cerebellum, and arbor vitae. Fig. 13.9 Be able to identify Cranial Nerves I an ...
Nervous System Notes File
Nervous System Notes File

...  Nerve impulse conduction is an ALL-OR-NONE response – if neuron responds at all, it responds completely! ...
introduction
introduction

... • A single stimulus produces an initial depolarizing response and after reaching its peak, declines exponentially. During this potential, the excitability of the neuron to other stimuli is increased. This potential is called excitatory postsynaptic potential (EPSP). • The excitatory transmitter open ...
Chapter 13: Peripheral Nervous System
Chapter 13: Peripheral Nervous System

...  Chains of three neurons (first-, second-, and third-order) conduct sensory impulses upward to the brain  First-order neurons – soma reside in dorsal root or cranial ganglia, and conduct impulses from the skin to the spinal cord or brain stem  Second-order neurons – soma reside in the dorsal horn ...
Nervous System
Nervous System

... Ependymal cells- line the central cavities of the brain and spinal cord; act as a semi-permeable lining between the cavities and normal tissue ...
nervous-system-terms
nervous-system-terms

... are received and sent from nerve cell to nerve cell along a nerve and through the spinal cord to the brain. The control centre of the body. It is an organ in the skull made from nerve cells. It receives messages from all parts of the body and sends out messages in return. A long rod made of many ner ...
Stimulating nerve cells with laser precision - Exploration
Stimulating nerve cells with laser precision - Exploration

... Photo by Dana Johnson that it is safe, they are turning their attention Pete Konrad during surgery to studying the exact mechanisms behind the stimulation effects. The most likely candidates, Jansen and Wells say, include a photothermal or mechanical effect, or perhaps a combination of the two. The ...
Principles of Electrical Currents
Principles of Electrical Currents

... amplitude is associated with the depth of penetration. The deeper the penetration the more muscle fiber recruitment possible remember the all or none response and the Arndt-Schultz Principle ...
CHAPTER 11 Nervous Tissue - Austin Community College
CHAPTER 11 Nervous Tissue - Austin Community College

... system is the master controlling system of the body. It is designed to constantly and rapidly adjust and respond to stimuli the body receives. It includes the brain, cranial nerves, spinal cord, and associated peripheral nerves. Divisions of the nervous sytem: ...
Guillain-Barré Syndrome
Guillain-Barré Syndrome

... and other upper respiratory symptoms  Infection with Epstein-Barr virus has been linked to milder forms of Guillain-Barré Syndrome  GI symptoms may be more likely to precede GuillainBarré subtypes that are related to slower recovery and higher risk of residual disability ...
Chapter 8 Nervous System
Chapter 8 Nervous System

... 1. Astrocytes – major support of the CNS – common site of CNS tumors – look like a star with some of their processes reaching out and wrapping around capillaries (create the blood brain barrier using tight junctions) 2. Ependymal – line the fluid filled cavities of the CNS – produce and move the cer ...
Exploring the Human Nervous System
Exploring the Human Nervous System

... rest of the body ...
sensory receptors, neuronal circuits for processing information
sensory receptors, neuronal circuits for processing information

... determined by the point in the nervous system to which the fiber leads  Pain ...
neurons - haltliappsych
neurons - haltliappsych

... neuron causing a tiny difference in electrical NA+ and charge across the cell K+ ARE membrane. MAJOR PLAYERS! ...
My Reaction Test Score = Neural Transmission
My Reaction Test Score = Neural Transmission

... axon. This wave of changing electrical charge flows down the axon until it reaches the terminal button. At the end (terminal button) of the axon the signal causes small sacks (vesicles) of chemicals to be released into the space between the end of the axon and the dendrite of the next neuron. These ...
Chapter 2
Chapter 2

... Resting potential – the membrane potential of a neuron when it is not being altered by excitatory or inhibitory postsynaptic potentials Excitatory vs Inhibitory ...
Nerve Flash Cards
Nerve Flash Cards

... A sheet of paper is like one of these cells, and it wraps itself around a pencil (axon), so there are many layers. The myelin sheath is an electrical insulator. BETWEEN the sheaths are nodes = NODES OF RANVIER; these are BARE regions of axonal membranes only found in myelinated axons. ...
File - Biology with Radjewski
File - Biology with Radjewski

... • Axons are covered by a lipid membrane called the myelin sheath (ring a bell?) – It insulates the axon – It speeds up the transmission of action potentials – Produced by Schwann cells that surround the axon – Gaps in the myelin sheath are called the Nodes of Ranvier ...
013368718X_CH31_483-498.indd
013368718X_CH31_483-498.indd

... Neurons Nervous system impulses are transmitted by cells called neurons. The three types of neurons are sensory, motor, and interneurons. All neurons have certain features: The cell body contains the nucleus and much of the cytoplasm. Dendrites receive impulses from other neurons and carry impulses ...
< 1 ... 237 238 239 240 241 242 243 244 245 ... 293 >

Rheobase



Rheobase is a measure of membrane excitability. In neuroscience, rheobase is the minimal current amplitude of infinite duration (in a practical sense, about 300 milliseconds) that results in the depolarization threshold of the cell membranes being reached, such as an action potential or the contraction of a muscle. In Greek, the root ""rhe"" translates to current or flow, and ""basi"" means bottom or foundation: thus the rheobase is the minimum current that will produce an action potential or muscle contraction.Rheobase can be best understood in the context of the strength-duration relationship (Fig. 1). The ease with which a membrane can be stimulated depends on two variables: the strength of the stimulus, and the duration for which the stimulus is applied. These variables are inversely related: as the strength of the applied current increases, the time required to stimulate the membrane decreases (and vice versa) to maintain a constant effect. Mathematically, rheobase is equivalent to half the current that needs to be applied for the duration of chronaxie, which is a strength-duration time constant that corresponds to the duration of time that elicits a response when the nerve is stimulated at twice rheobasic strength.The strength-duration curve was first discovered by G. Weiss in 1901, but it was not until 1909 that Louis Lapicque coined the term ""rheobase"". Many studies are being conducted in relation to rheobase values and the dynamic changes throughout maturation and between different nerve fibers. In the past strength-duration curves and rheobase determinations were used to assess nerve injury; today, they play a role in clinical identification of many neurological pathologies, including as Diabetic neuropathy, CIDP, Machado-Joseph Disease, and ALS.
  • studyres.com © 2025
  • DMCA
  • Privacy
  • Terms
  • Report