The phrase "average contrast thresholds" is correct and usable in written English.
It can be used in contexts related to vision science, psychology, or any field that discusses visual perception and measurement.
Example: "The study aimed to determine the average contrast thresholds for different age groups to understand how vision changes over time."
Alternatives: "mean contrast thresholds" or "typical contrast thresholds".
In the lowest three external noise conditions, the average contrast thresholds of day 1/2 are 0.12±0.03 and 0.09±0.01 for the WD and control subjects, respectively, with no significant difference between them (t(18) = 1.371, p>0.10).
In the highest two external noise conditions, the average contrast thresholds of day 1/2 are 0.56±0.07 and 0.46±0.07 for the WD and control subjects, respectively, with no significant difference between them (t(18) = 0.194, p>0.30).
Perceptual learning reduced the average contrast threshold by 4.57±1.22 dB for the WD subjects, and by 4.33±0.40 dB for the control subjects (Figure 4E).
Perceptual learning reduced the average contrast threshold by 3.04±0.74 dB for the WD group, and 4.66±0.25 dB for the control group.
The time course of perceptual learning was also not significantly different between the two groups (all p>0.10): The average contrast threshold reduction in every two consecutive training sessions are 2.14±0.52, 1.73±0.68, and 0.71±0.24 in the WD group, and 3.15±0.54, 0.98±0.18, and 0.20±0.26 in the control group.
Spearman correlation coefficients were in addition computed between mean accommodation response (accommodation response7-min average) and mean contrast thresholds (contrast threshold7-min average) for each viewing condition for the purpose of assessing the internal validity of the results obtained with two different measurement techniques.
GEE was used to assess the relationship between 1 min means of contrast thresholds (contrast threshold1-min averages) and accommodation responses (accommodation response1-min averages) with time (min 1 7) to ascertain if the two sets of response measures were stable.
The discrimination threshold was calculated as the average contrast or orientation of the pop-out grating.
Since there was a significant effect of time on accommodation response in condition MM (see Sect. " Accommodation responses and contrast thresholds"; Fig. 3), the variable accommodation response1-min averages was used when analyzing condition MM.
For all subjects, contrast thresholds were assessed in Maxwellian-view.
(3) Different contrast levels converge onto an average contrast.
