The Nervous System - riverridge210.org
... 4. Most important feature is there are small nodes or gaps in thy myelin allowing the impulse to jump from note to node instead of moving along the membrane. Jumping greatly increases the speed of the impulse. 5. The minimum level of a stimulus that is required to activate a neuron is called a thre ...
... 4. Most important feature is there are small nodes or gaps in thy myelin allowing the impulse to jump from note to node instead of moving along the membrane. Jumping greatly increases the speed of the impulse. 5. The minimum level of a stimulus that is required to activate a neuron is called a thre ...
Nervous System - WordPress.com
... Regarding the resting membrane potential in peripheral nerves: a) membrane permeability of potassium ions via K+ leak channels produces the resting potential b) a decrease in extracellular Ca2+ decreases excitability c) decreasing external Na+ concentration lowers the resting membrane potential d) c ...
... Regarding the resting membrane potential in peripheral nerves: a) membrane permeability of potassium ions via K+ leak channels produces the resting potential b) a decrease in extracellular Ca2+ decreases excitability c) decreasing external Na+ concentration lowers the resting membrane potential d) c ...
Sensation
... Pinna: Collects sounds. Shaped like a funnel Auditory canal: The auditory canal is a tube that connects the pinna and the tympanic membrane (eardrum) ...
... Pinna: Collects sounds. Shaped like a funnel Auditory canal: The auditory canal is a tube that connects the pinna and the tympanic membrane (eardrum) ...
Motor Areas - Motlow State Community College
... relates present and past visual experiences essential in recognizing and evaluating what is seen ...
... relates present and past visual experiences essential in recognizing and evaluating what is seen ...
Nervous System
... stimulates neurons connecting to the optic nerve. • Rod cells detect amount of light, cone cells distinguish ...
... stimulates neurons connecting to the optic nerve. • Rod cells detect amount of light, cone cells distinguish ...
brain movement and disorder
... Without this supraspinal innervation, such as after acute stroke, there is not enough background excitation of alpha motor neurons to sustain a reflex. Ultimately the 1A fibers sprout more synaptic knobs so alpha motor neurons are excited by stretch alone ...
... Without this supraspinal innervation, such as after acute stroke, there is not enough background excitation of alpha motor neurons to sustain a reflex. Ultimately the 1A fibers sprout more synaptic knobs so alpha motor neurons are excited by stretch alone ...
Neurobiology
... • The myelin sheath is segmental, presenting discontinuities at ( ) regular intervals (forming the nodes of Ranvier). • Voltage-gated Na+ and K+ channels are clustered at the nodes. • The lipid-rich, water-poor, nature of compact myelin gives the latter good electrical insulating properties. • Actio ...
... • The myelin sheath is segmental, presenting discontinuities at ( ) regular intervals (forming the nodes of Ranvier). • Voltage-gated Na+ and K+ channels are clustered at the nodes. • The lipid-rich, water-poor, nature of compact myelin gives the latter good electrical insulating properties. • Actio ...
Fig. 6.1
... • Every time another potassium ion leaves the cell, it adds to the force that pushes potassium ions back into the cell. • Within milliseconds an equilibrium is reached • It is reached after just 2 million out of 0.5 trillion potassium ions leave the cell ...
... • Every time another potassium ion leaves the cell, it adds to the force that pushes potassium ions back into the cell. • Within milliseconds an equilibrium is reached • It is reached after just 2 million out of 0.5 trillion potassium ions leave the cell ...
Functional Organization of Nervous Tissue
... medial epicondyle of the humerus will produce strong tingling sensations along the forearm and hand. (a) Radial (b) Median (c) Phrenic (d) Femoral (e) Ulnar ...
... medial epicondyle of the humerus will produce strong tingling sensations along the forearm and hand. (a) Radial (b) Median (c) Phrenic (d) Femoral (e) Ulnar ...
Central Tendency” - North Dakota State University
... 4. After a series of higher than normal stimulations followed by a rest period, a baseline stimulation to a neuron elicits a greater excitatory post synaptic potential from another neuron that receives it’s projections. This phenomenon is known as: a. kindling b. long-term potentiation c. ischemia ...
... 4. After a series of higher than normal stimulations followed by a rest period, a baseline stimulation to a neuron elicits a greater excitatory post synaptic potential from another neuron that receives it’s projections. This phenomenon is known as: a. kindling b. long-term potentiation c. ischemia ...
CHAPTER OUTLINE
... Color blindness and problems with visual focus are two common abnormalities of the eye. More serious disorders can result in blindness. Color Blindness Complete color blindness is extremely rare. In most instances, a particular type of cone is lacking or deficient in number. Visual Focus The majorit ...
... Color blindness and problems with visual focus are two common abnormalities of the eye. More serious disorders can result in blindness. Color Blindness Complete color blindness is extremely rare. In most instances, a particular type of cone is lacking or deficient in number. Visual Focus The majorit ...
Nerve Cells and Nerve Impulses
... other cells. A single neuron may have thousands of dendrites, so it can communicate with thousands of other cells but only one axon. The axon is covered with a myelin sheath, a fatty layer that insulates the axon and allows the electrical signal to travel much more quickly. The node of Ranvier is an ...
... other cells. A single neuron may have thousands of dendrites, so it can communicate with thousands of other cells but only one axon. The axon is covered with a myelin sheath, a fatty layer that insulates the axon and allows the electrical signal to travel much more quickly. The node of Ranvier is an ...
What is Superior Laryngeal Nerve Paresis
... susceptible to viral infections for some reason, and this kind of weakness is fairly common. When a virus affects the nerve, it swells and cannot deliver all of the information to the muscle, so the muscle becomes weak and does not function to its potential. That’s generally when the vocal symptoms ...
... susceptible to viral infections for some reason, and this kind of weakness is fairly common. When a virus affects the nerve, it swells and cannot deliver all of the information to the muscle, so the muscle becomes weak and does not function to its potential. That’s generally when the vocal symptoms ...
22 reflexes 1 - The reflex arc
... The frequency of the action potentials is what determines the intensity of the stimulus At the synapse, the action potentials from the afferent neuron produce excitatory post synaptic potentials in the efferent neuron If these excitatory potentials summate enough to bring the efferent membrane to th ...
... The frequency of the action potentials is what determines the intensity of the stimulus At the synapse, the action potentials from the afferent neuron produce excitatory post synaptic potentials in the efferent neuron If these excitatory potentials summate enough to bring the efferent membrane to th ...
Physiology Lecture Outline: Membrane Potential and Neurophysiology
... This is not what actually happens at the Nodes of Ranvier, but at this stage it is convenient to think of the signal 'jumping' down the myelinated axon significantly faster than a non-myelinated axon. Of these three factors that can effect the speed of an action potential traveling down an axon, (di ...
... This is not what actually happens at the Nodes of Ranvier, but at this stage it is convenient to think of the signal 'jumping' down the myelinated axon significantly faster than a non-myelinated axon. Of these three factors that can effect the speed of an action potential traveling down an axon, (di ...
Sensory Physiology
... Somatic afferent fibers – carries impulses from skin, skeletal muscles and joints Visceral afferent fibers – carries impulses from organs within ventral body cavities Special sense afferent fibers – eyes, ears, taste, smell ...
... Somatic afferent fibers – carries impulses from skin, skeletal muscles and joints Visceral afferent fibers – carries impulses from organs within ventral body cavities Special sense afferent fibers – eyes, ears, taste, smell ...
Sensory Physiology
... carries impulses from skin, skeletal muscles and joints Visceral afferent fibers – carries impulses from organs within ventral body cavities Special sense afferent fibers – eyes, ears, taste, smell ...
... carries impulses from skin, skeletal muscles and joints Visceral afferent fibers – carries impulses from organs within ventral body cavities Special sense afferent fibers – eyes, ears, taste, smell ...
PowerPoint to accompany Hole’s Human Anatomy and
... • Neurons share certain features: • Dendrites • A cell body ...
... • Neurons share certain features: • Dendrites • A cell body ...
Central Nervous System
... Fine coordination: 3 main functions ____________________________________ ____________________________________ Flocculonodular lobe= _________________________ Hemispheres separated by falx cerebelli Cerebellar cortex – gray ...
... Fine coordination: 3 main functions ____________________________________ ____________________________________ Flocculonodular lobe= _________________________ Hemispheres separated by falx cerebelli Cerebellar cortex – gray ...
Nervous & Endocrine Systems
... 2. Receptors in your ear pick the sound of a ringing phone 5. Receptors trigger nerve impulses in sensory neurons 1. The nerve impulses pass to interneurons in the brain. 6. Your brain interprets the impulses from many interneurons and you realize the phone is ringing. Your brain also decides that y ...
... 2. Receptors in your ear pick the sound of a ringing phone 5. Receptors trigger nerve impulses in sensory neurons 1. The nerve impulses pass to interneurons in the brain. 6. Your brain interprets the impulses from many interneurons and you realize the phone is ringing. Your brain also decides that y ...
THE NERVOUS SYSTEM (PART II): THE TRAFFIC CONTROL
... structures and their corresponding functions of the brain ...
... structures and their corresponding functions of the brain ...
NeuralCell-Neurons.stud
... Neurons differ from Other Cells 1. Neurons have specialized projections called dendrites and axons. Dendrites take information to the cell body and axons take information away from the cell body 2. Neurons communicate with each other through an electrochemical process 3. Neurons contain some specia ...
... Neurons differ from Other Cells 1. Neurons have specialized projections called dendrites and axons. Dendrites take information to the cell body and axons take information away from the cell body 2. Neurons communicate with each other through an electrochemical process 3. Neurons contain some specia ...
Bidirectional propagation of Action potentials
... Signal propagation can be described uniform for neurons, regardsless of different neuron shapes and functions, in a model neuron. A signal travelling through the neuron can be seen as a linkage between four components. A input component, a trigger component, a long-distance component and a secretory ...
... Signal propagation can be described uniform for neurons, regardsless of different neuron shapes and functions, in a model neuron. A signal travelling through the neuron can be seen as a linkage between four components. A input component, a trigger component, a long-distance component and a secretory ...
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.