What do you mean by orthodromic conduction?
What do you mean by orthodromic conduction?
Orthodromic denotes the propagation of an impulse along a conduction system (for example, nerve fiber) in the direction it normally travels. Compare: antidromic. In the heart, orthodromic refers to an impulse going in the correct direction from the atria to the ventricles, in contrast to some impulses in re-entry.
What is orthodromic and antidromic conduction?
In an orthodromic study, the recording electrodes measure the action potential traveling in the physiologic direction. In an antidromic study, the recording electrodes measure the action potential traveling opposite the physiologic direction.
What is the antidromic conduction?
An antidromic impulse in an axon refers to conduction opposite of the normal (orthodromic) direction. That is, it refers to conduction along the axon away from the axon terminal(s) and towards the soma.
How is it possible for an axon to generate an antidromic action potential?
Electrical stimulation of the central nervous system creates both orthodromically propagating action potentials, by stimulation of local cells and passing axons, and antidromically propagating action potentials, by stimulation of presynaptic axons and terminals.
What is Chronaxie and Rheobase?
Rheobase—The minimum current required to depolarize a nerve given an infinite duration of stimulation. Chronaxie—The duration of current required to depolarize a nerve to threshold when the current is two times the rheobase.
What is axonal hillock?
In nervous system: Axon. …at a region called the axon hillock, or initial segment. This is the region where the plasma membrane generates nerve impulses; the axon conducts these impulses away from the soma or dendrites toward other neurons.
Is WPW antidromic vs orthodromic?
Types of arrhythmias in WPW are AVRT (80%). There are two type of AVRT, orthodromic (90 to 95%) vs. antidromic (5%), other types are atrial fibrillation (AF) (10% to 30%), atrial flutter, and ventricular tachycardia/ventricular fibrillation [4-7]. The different types of arrhythmias are shown in Figure 5.
How do you identify Wolff Parkinson White on ECG?
Classic ECG findings that are associated with WPW syndrome include the following:
- Presence of a short PR interval (<120 ms)
- A wide QRS complex longer than 120 ms with a slurred onset of the QRS waveform, termed a delta wave, in the early part of QRS.
- Secondary ST-T wave changes (see the image below)
What is chronaxie in biology?
Definition of chronaxie : the minimum time required for excitation of a structure (such as a neuron) by a constant electric current of twice the threshold voltage.
What is the difference between rheobase and threshold?
The threshold , or minimal stimulus , is defined as “the electrical stimulus whose strength (or voltage) is sufficient to excite the tissue. Rheobase is defined as “the minimum strength (voltage) of stimulus which can excite the tissue”.
Is axon hillock the same as axon terminal?
The axon hillock is the last site in the soma where membrane potentials propagated from synaptic inputs are summated before being transmitted to the axon….
| Axon hillock | |
|---|---|
| Red labeled is pointing directly at the axon hillock. | |
| Details | |
| Part of | Axon of a nerve |
| System | Nervous system |
What is an axolemma?
Medical Definition of axolemma : the plasma membrane of an axon For a short time after the passage of a nerve impulse along a nerve fiber, while the axolemma is still depolarized, a second stimulus, however strong, is unable to excite the nerve. —