refractory period

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period

 [pēr´e-od]
an interval or division of time; the time for the regular recurrence of a phenomenon.
absolute refractory period the part of the refractory period from phase 0 to approximately −60 mV during phase 3; during this time it is impossible for the myocardium to respond with a propagated action potential, even with a strong stimulus. Called also effective refractory period.
blanking period a period of time during and after a pacemaker stimulus when the unstimulated chamber is insensitive to avoid sensing the electronic event in the stimulated chamber.
effective refractory period absolute refractory period.
ejection period the second phase of ventricular systole (0.21 to 0.30 sec), between the opening and closing of the semilunar valves, while the blood is discharged into the aorta and pulmonary artery. Called also sphygmic period.
gestation period see gestation period.
incubation period see incubation period.
isoelectric period the moment in muscular contraction when no deflection of the galvanometer is produced.
latency period
latent period a seemingly inactive period, as that between exposure to an infection and the onset of illness (incubation period) or that between the instant of stimulation and the beginning of response (latency, def. 2).
refractory period the period of depolarization and repolarization of the cell membrane after excitation; during the first portion (absolute refractory period), the nerve or muscle fiber cannot respond to a second stimulus, whereas during the relative refractory period it can respond only to a strong stimulus.
relative refractory period the part of the refractory period from approximately −60 mV during phase 3 to the end of phase 3; during this time a depressed response to a strong stimulus is possible.
safe period the period during the menstrual cycle when conception is considered least likely to occur; it comprises approximately the ten days after menstruation begins and the ten days preceding menstruation. See the section on fertility awareness methods, under contraception.
sphygmic period ejection period.
supernormal period in electrocardiography, a period at the end of phase 3 of the action potential during which activation can be initiated with a milder stimulus than is required at maximal repolarization, because at this time the cell is excitable and closer to threshold than at maximal diastolic potential.
vulnerable period that time at the peak of the T wave during which serious arrhythmias are likely to result if a stimulus occurs.
Wenckebach's period a usually repetitive sequence seen in partial heart block, marked by progressive lengthening of the P–R interval; see also dropped beat.

re·frac·to·ry pe·ri·od

1. the period following effective stimulation, during which excitable tissue such as heart muscle and nerve fails to respond to a stimulus of threshold intensity (that is, excitability is depressed);
2. a period of temporary psychophysiologic resistance to further sexual stimulation that occurs immediately following orgasm.

refractory period

the time from phase 0 to the end of phase 3 of the action potential, divided into effective and relative. In pacing terminology, the period during which a pulse generator is unresponsive to an input signal of specified amplitude. The effective refractory period is from phase 0 to approximately -60 mV during phase 3 of the action potential, a time during which it is impossible for the myocardium to respond with a propagated action potential, or even to a strong stimulus. The relative refractory period is from approximately -60 mV during phase 3 to the end of phase 3 of the action potential, the time during which a depressed response is possible to a strong stimulus. Also called refractory phase, refractory state.
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Refractory period

refractory period

A component of the resolution phase, the fourth and final phase of Masters and Johnson’s four-stage model of physiological responses to sexual stimulation, which follows the orgasmic phase. During the refractory period, it is typically physiologically impossible for males to have additional orgasms: the male is sexually satiated physically, and the penis is flaccid and unerectable. Further stimulation of the now hypersensitive penis may even be painful. As further orgasm may be achieved by females following the first, they typically do not have a refractory period.

refractory period

Cardiac pacing The time during which a pacemaker's sensing mechanism is nonresponsive–in full or in part to cardiac activity–eg, to a retrograde P-wave in a DDD pacemaker. See Pacemaker Sexuality A post-orgasm recovery period lasting from mins to hrs during which the penis is unerectable. See Erection.

re·frac·to·ry pe·ri·od

(rĕ-frak'tŏr-ē pēr'ē-ŏd)
1. The time following effective stimulation, during which excitable tissue such as heart muscle and nerve fails to respond to a stimulus of threshold intensity (i.e., excitability is depressed).
2. A period of temporary psychophysiologic resistance to further sexual stimulation, which occurs immediately following orgasm.

refractory period

The period immediately following the passage of a nerve impulse or the contraction of a muscle fibre during which a stimulus, normally capable of promoting a response, has no effect.

refractory period

the period of inexcitability, that normally lasts about three milliseconds, during which the AXON recovers after it has transmitted an impulse. During the refractory period it is impossible for the axon to transmit another impulse, because the membrane is being repolarized by ionic movements at this time. During the absolute refractory period no NERVE IMPULSE can be transmitted, but during the relative refractory period an impulse can be transmitted providing the stimulus is strong.

re·frac·to·ry pe·ri·od

(rē-frak'tŏr-ē pēr'ē-ŏd)
Duration following effective stimulation, during which excitable tissue fails to respond to a stimulus.

refractory

not readily yielding to treatment.

refractory period
the period of depolarization and repolarization of the cell membrane after excitation; during the first portion (absolute refractory period), the nerve or muscle fiber cannot respond to a second stimulus, whereas during the relative refractory period, it can respond only to a strong stimulus.
myocardial refractory state
the myocardium is refractory to stimulation during the action potential period, excitability returning in the repolarization phase; initially there is a period of supernormality.
References in periodicals archive ?
Based on the homologous genital anatomy of men and women, one might anticipate that the refractory period, if it is mediated peripherally, would have an anatomical basis for being present in women, as well as men, but expressed differently.
2002) point out that there are probably other mechanisms involved in the physiological regulation of erection in men post-orgasmically since the male refractory period is typically more on the order of 15 minutes rather than 60 minutes.
The release of prolactin is thought to be largely responsible for the post-orgasmic refractory period seen in men (Kruger et al.
These men do not have a post-orgasmic refractory period and their orgasms are followed by neither detumescence nor hypersensitivity of the glans of the penis.
Based on the foregoing background, we considered it important to determine whether women experience anything like the refractory period that is so well documented in men.
This exploratory study was prompted by the lack of research on the post-orgasmic experiences of women and by the apparent assumption in the literature that women either do not have a post-orgasmic refractory period characterized by genital hypersensivity and reduced arousability as in men or are they are less affected by it.