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What is differential threshold?

Updated: 12/8/2022
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The differential threshold of retinal sensitivity, as contrasted with the absolute threshold, has also been investigated in amblyopic eyes. In testing the differential threshold, one asks how much brighter than its surroundings a test field must be so that it may be just perceived.

A number of workers studied this question, and most found a slight elevation of the differential threshold of amblyopic eyes, provided the test field was small enough, on the order of magnitude of a few minutes. In other words, a small, shallow relative scotoma of the amblyopic eyes could be shown to exist. Various methods have been used to establish this fact, among them monocular static perimetry. Aulhorn19reported on 70 amblyopes tested with this method, 35 of whom had foveolar or extrafoveolar depression, 26 had only flattening of the curve, and 9 had the normal foveolar peak in their sensitivity curve. Donahue and coworkers120 recently revisited this problem, using automated perimetry. They found that all types of amblyopia are associated with a generalized depression of light sensitivity, which was proportionately greatest at the fovea and highly correlated with visual acuity loss.

A higher-than-normal central differential threshold was also found by EF Miller309 under photopic conditions using rectangular test objects in the shape of luminous bars or slits of different widths. Grosvenor174 confirmed the work of Miller but added important amplifications by testing normal and amblyopic eyes over a wide range of exposure times and background luminance levels. He found that "the normal and amblyopic eyes have essentially equal thresholds at the absolute threshold level, which substantiates the work of Wald and Burian." In addition, the fact that the thresholds for the two eyes are not the same at higher luminance levels "bears out their prediction that amblyopia has its effects mainly at higher levels of luminance."174 Because of the impaired differential threshold of the light-adapted amblyopic eyes, Harms184 questioned the conclusion by Wald and Burian457 that the entire apparatus of simple light perception was normal in amblyopic eyes. However, Wald456 pointed out that every brightness discrimination involved some degree of form discrimination, which indeed is impaired in amblyopia. Jung234 explained the apparent contradiction between the findings of Wald and Burian and those of Harms by the following neurophysiologic considerations. The lateral inhibition, essential to contrast vision and visual acuity, disappears in dark adaptation, and spatial summation prevails. For scotopic vision there is no reduction in darklight perception, and diffuse light perception is retained by the amblyopic eye. This favors a separate neuronal mechanism for brightness perception.

Herzau and coworkers201 measured the differential light thresholds in the nasal and temporal visual field periphery in patients with strabismic amblyopia and found consistent threshold elevation in the nasal field. These data may be the psychophysical correlate of our finding that in human strabismic amblyopia the LGN has the most pronounced cell shrinkage in layers connected with the temporal retina, which corresponds to the nasal visual field.348

Bowering and coworkers53 evaluated the visual field with manual Goldmann perimetry in patients with deprivation amblyopia from congenital cataracts. They found in all children a restricted field, especially temporally, even when the deprivation began as late as 6 years of age and lasted less than 6 months. The restrictions were larger than those shown by the adults who developed cataracts. The restrictions were also larger after longer deprivation and monocular deprivation than after binocular deprivation. However, children who regularly patched the fellow nondeprived eye and, therefore, experienced less interocular competition, exhibited smaller restrictions temporally. Neither visual acuity nor optical factors could account for all of the restrictions in the deprived children.

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Q: What is differential threshold?
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What is the difference between absolute threshold and difference threshold?

absolute threshold is the lowest level that a person will feel sensation differential threshold is the minimal difference that a person can detect between two similar stimuli For example a change in volume in certain frequencies would be crossing the absolute threshold, how much that change would need to be for someone to detect it would be dealing with the difference threshold.


What is the difference between absolute differential threshold?

ABSOLUTE THRESHOLD The smallest intensity of a stimulus that can reliably evoke a sensation. EXAMPLE THE IMPACT OF UPWARD PRICE MOVEMENTS ON DAILY HOUSEHOLD GOODS. THIS SHOWS THE IMPORTANCE OF MARKET SEGMENTATION AND THE ASSOCIATED PRICING POLICIES. ================================================== DIFFERENTIAL THRESHOLD. Difference Threshold: The difference threshold, also known as the just noticeable difference (jnd), is the minimum difference in stimulation that a person can detect 50 percent of the time. We experience the difference threshold as a just noticeable difference. For example, let's say I asked you to put your hand out and in it I placed a pile of sand. Then, I add tiny amounts of sand to your hand and ask you to tell me when you notice any change in the overall weight. As soon as you can detect any change in the weight, that difference between the weight of the sand before I added that last bit of sand and the amount of sand after I added it, is the difference threshold. How do marketers apply the concept of differential threshold or 'just noticeable difference' in their marketing strategy? Explain giving suitable examples. The concept of differential threshold is applied to almost all aspects of marketing strategies. 1.PRODUCTLINE EXTENSION. This concept is applied to the advertising/ promotion of the productline, in order to exploit the strength of the original brand. ------------------------------------------------------------------------------- 2.DISTRIBUTION CHANNELS The marketers' apply the concept of differential threshold in the selection of the distribution channels, for the various products from the same family productgroup. ----------------------------------------------------------------------------------------- 3.PRODUCT PRICING The marketers' apply the concept of differential threshold in the PRICING of the two brands from the same company --like two toothpaste brands from one company. ------------------------------------------------------------------------ 4.PRODUCT PROMOTIONS The marketers' apply the concept of differential threshold in the DEVELOPMENT/ IMPLEMENTATION of the sales promotion programs in two channels to maintain similarity / cost down. -------------------------------------------------------------------------- 5. PRODUCT PACKAGING The marketers' apply the concept of differential threshold in the PACKAGING of the various models of the company products / to create uniform image. ------------------------------------------------------------------------- 6. PRODUCT PERCEPTION/ IMAGE The marketers' apply the concept of differential threshold in the PRODUCT POSITIONING in more than one market segments. ------------------------------------------------------------------------------


What is the difference between threshold of hearing and absolute threshold of hearing?

The absolute threshold of hearing is the lowest possible tone/decibel you could possibly hear. (This differs form person to person). The Differential Threshold is the point at which a person recognizes the decibel level has changed.Hope this answers your question, just learned this in psychology!


What is the differences between the absolute threshold and the differential threshold Which is more important to marketers?

The absolute threshold is the minimum intensity of stimulus required to be perceived. In other words, it is the intensity amount which is needed to detect the difference between nothing and something. It is the lowest level at which an individual can experience a sensation.On the other hand, the minimal difference that can be detected between two stimuli is called the difference threshold or the j.n.d. (just noticeable difference)The main difference between the two concepts is that the differential threshold is a relative concept. Whereas the absolute threshold deals with whether or not a stimulus can be perceived, the differential threshold refers to the intensity difference needed between two stimuli before people can perceive that the stimuli are different.The marketing implication of absolute threshold is that consumers will only perceive a marketing stimulus when it is higher than absolute threshold. In other words, if images or words in a commercial are too small, consumer's sensory receptors will not ve activated and the stimulus will not be perceived. The differential threshold also has very important marketing applications Difference Threshold: The difference threshold, also known as the just noticeable difference (jnd), is the minimum difference in stimulation that a person can detect 50 percent of the time. We experience the difference threshold as a just noticeable difference. For example, let's say I asked you to put your hand out and in it I placed a pile of sand. Then, I add tiny amounts of sand to your hand and ask you to tell me when you notice any change in the overall weight. As soon as you can detect any change in the weight, that difference between the weight of the sand before I added that last bit of sand and the amount of sand after I added it, is the difference threshold.The absolute threshold is the minimum intensity of stimulus required to be perceived. In other words, it is the intensity amount which is needed to detect the difference between nothing and something. It is the lowest level at which an individual can experience a sensation.On the other hand, the minimal difference that can be detected between two stimuli is called the difference threshold or the j.n.d. (just noticeable difference)The main difference between the two concepts is that the differential threshold is a relative concept. Whereas the absolute threshold deals with whether or not a stimulus can be perceived, the differential threshold refers to the intensity difference needed between two stimuli before people can perceive that the stimuli are different.The marketing implication of absolute threshold is that consumers will only perceive a marketing stimulus when it is higher than absolute threshold. In other words, if images or words in a commercial are too small, consumer's sensory receptors will not ve activated and the stimulus will not be perceived. The differential threshold also has very important marketing applications


When was From Threshold to Threshold created?

From Threshold to Threshold was created in 1955.


What is a antonym of threshold?

anti-threshold


What rhymes with threshold?

There are no perfect rhymes for threshold.


Threshold of human in db?

The threshold of hearing is 0 dB. The threshold of pain = 137.5 dB.


How do you spell theshhold?

threshold - After the wedding ceremony he carried her over the threshold of their new home.


When was Threshold House created?

Threshold House was created in 1987.


When was Threshold Editions created?

Threshold Editions was created in 2005.


Who wrote Threshold?

The Golden Threshold was written by Sarojini Naidu.