| retrograde conduction | Conduction backward from the ventricles or from the A-V node into and through the atria. Synonym: retroconduction, ventriculoatrial conduction, V-A conduction. (05 Mar 2000) |
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| concealed conduction | Conduction of an impulse through a part of the heart without direct evidence of its presence in the electrocardiogram; conduction is inferred only because of its influence on the subsequent cardiac cycle. (05 Mar 2000) |
| conduction | <physics, physiology> The transfer of sound waves, heat, nervous impulses or electricity. Origin: L. Conductio (18 Nov 1997) |
| conduction anaesthesia | Regional anaesthesia in which local anaesthetic solution is injected about nerves to inhibit nerve transmission; includes spinal, epidural, nerve block, and field block anaesthesia, but not local or topical anaesthesia. Synonym: block anaesthesia. (05 Mar 2000) |
| conduction analgesia | Use of local anaesthetic solution(s) to produce circumscribed areas of loss of sensation; a generic term including conduction, nerve block, spinal, epidural, field block, infiltration, and topical anaesthesia. Synonym: conduction analgesia. (05 Mar 2000) |
| conduction aphasia | A form of aphasia in which the patient understands spoken and written words, is aware of his deficit, and can speak and write, but skips or repeats words, or substitutes one word for another (paraphasia);word repetition is severely impaired. The responsible lesion is in the associate tracks connecting the various language centres. Synonym: associative aphasia. (05 Mar 2000) |
| conduction block | Failure of impulse transmission at some point along a nerve, although conduction along the segments proximal and distal to it are unaffected. Clinically, most often caused by an area of focal demyelination; when caused by focal trauma, called neurapraxia. (05 Mar 2000) |
| heart conduction system | An impulse-conducting system composed of modified cardiac muscle and having the power of spontaneous rhythmicity and conduction more highly developed than the rest of the heart. (12 Dec 1998) |
| saltatory conduction | A method of neuronal transmission in vertebrate nerves, where only specialised nodes of Ranvier participate in excitation. This reduces the capacitance of the neuron, allowing much faster transmission. See: myelin, Schwann cells. (18 Nov 1997) |
| Purkinje conduction | <neurology, physiology> Conduction of the cardiac impulse through the Purkinje system. (05 Mar 2000) |
| sinoventricular conduction | <cardiology, physiology> A rare form of conduction of the sinus impulse during paralysis of the atrial muscle by hyperkalaemia. The impulse leaves the sinus node and enters the internodal tracts rapidly achieving the junctional tissues but without inscribing a P wave due to the inactivation of the atrial muscle cells. (05 Mar 2000) |
| nerve conduction | The transmission of an impulse along a nerve fibre. (05 Mar 2000) |
| nerve conduction velocity | The rate of impulse conduction in a peripheral nerve or its various component fibres, generally expressed in meters per second. (05 Mar 2000) |
| decremental conduction | Impaired conduction in a portion of a fibre because of progressively lessening response of the unexcited portion of the fibre to the action potential coming toward it; it is manifested by decreasing speed of conduction, amplitude of action potential, and extent of spread of the impulse. (05 Mar 2000) |
| supranormal conduction | Transmission of an impulse during the brief period of the cardiac cycle when it would be expected to fail if it occurred outside this time interval. Compare: supranormal excitability. (05 Mar 2000) |