An absolute threshold was seen as a hypothetical barrier that incoming stimuli must overcome before they can be perceived, it was based on the ability to pass through the threshold based on absolute judgements about a single stimulus. In the case where a person were to, for example- detect a light, the strength of said light would have to be strong enough to pass the threshold for an observer to perceive it, it was generally based on the observer's ability to detect a signal.In reality however, there is no such threshold that splits the stimulus dimension into detectable and undetectable components. Rather, a stimulus must yield a sensation that exceeds the decision criterion (beta) for even the weakest signal to be perceived, so a decision threshold is the stimulus that elicits the response or perception. The detectability and reporting of the presence of a signal- or the light- are both factors because the decision threshold must be passed and the results from the strength of the stimulus, for example the light- as well the evidence of yielding such strength, must be plausible. Only in this case, do we have correct detection of a signal.
The Lurker at the Threshold was created in 1945.
Threshold - 2012 I was released on: USA: 2012
Threshold - TV series - ended on 2006-02-01.
Threshold The Blue Angels Experience - 1975 was released on: USA: September 1975
The threshold stimulus is the stimulus required to create an action potential. So any stimulus under this level will not cause muscle contraction, while a stimulus above this level will cause the muscle to contract. The higher the stimulus the more muscle fibers are recruited, and thus the higher the response.
it is known as the threshold stimulus usually seen in tonic contraction
Yes. ....Up to a point. There is a threshold the stimulus must surpass before creating a CAP (compound action potential). Anything below this threshold is called subthreshold. Once the stimulus is strong enough cause a CAP it is a stimulus threshold. At this point the CAP will continue to increase as the intensity of the stimulus increases (now termed suprathreshold) until a maximal stimulus causes a maximum response. Any stimulus stronger than the maximal stimulus is called a supramaximal and does not result in any larger a CAP than the maximum response caused by the maximal stimulus. source: http://www.unmc.edu/physiology/Mann/mann12.html
An action potential needs to occur to trigger the neurons but the action potential depends on whether a stimulus is able to bring the membrane potential to a certain level termed the THRESHOLD. This threshold is about -55 mV for most neurons, but the stimulus needs to bring the membrane potential to this certain level or it will not be triggered. Relating to the ALL-OR-NONE PRINCIPLE, which if the threshold is not acquired then an action potential will not occur but once a stimulus is strong enough to depolarize (making the inside of the cell less negative going from -70 mV to -55 mV) it will trigger. The resting potential is -70 mV which the stimulus needs to bring it up to -55mV.
it will not respond until it reaches the threshold level