Psycho-physical Staircase
Psycho-physical Staircase - Related Videos
06:48
The Staircase Procedure for Finding a Perceptual Threshold
0 Views •
2023
Source: Laboratory of Jonathan Flombaum—Johns Hopkins University Psychophysics is the name for a set of methods in perceptual psychology designed in order to relate the actual intensity of stimuli to their perceptual intensity. One important aspect of psychophysics involves the measurement of perceptual thresholds: How bright does a light need to be for a person to be able to detect it? How little pressure applied to the skin is detectable? How soft can a sound be and still be heard? Put...
02:39
Staircase Test for Motor Function Assessment in a Hemiparkinsonian Rat
0 Views •
2025
This video demonstrates the staircase test to assess motor function in a hemiparkinsonian rat with a right brain lesion. The lesion disrupts dopamine signaling, impairing left paw control, which results in more pellets remaining on the left stairs, indicating motor dysfunction.
07:14
A Novel Approach to Assess Motor Outcome of Deep Brain Stimulation Effects in the Hemiparkinsonian Rat: Staircase and Cylinder Test
0 Views •
Cited by 7 •
2016
Deep brain stimulation (DBS) is an effective treatment option for Parkinson's disease. We established a study design to screen novel stimulation paradigms in rats. The protocol describes the use of the staircase test and cylinder test for motor outcome assessment in DBS treated hemiparkinsonian rats.
07:28
Psychophysically-anchored, Robust Thresholding in Studying Pain-related Lateralization of Oscillatory Prestimulus Activity
0 Views •
Cited by 8 •
2017
Psychophysical methods such as the QUEST estimation procedure can efficiently yield robust estimates of the stimulation intensity at which nonpainful sensations transition into painful sensations. By stimulating repeatedly at the threshold intensity, the variability in rating responses can directly be attributed to perceptual classifications in subsequent analyses.
09:17
Psychophysical Tracking Method to Measure Taste Preferences in Children and Adults
0 Views •
Cited by 10 •
2016
Sweet taste has powerful hedonic appeal among people of all ages, particularly children. Described herein is a reliable and valid method that can be used to determine the level of sweetness most preferred, making it a valuable psychophysical tool for scientists.
FAQs
Step size controls the balance between speed and precision. Larger intensity changes move the procedure more rapidly toward the participant’s performance region, while smaller changes support a finer estimate but may require more trials. Selecting the step size therefore determines how efficiently the staircase approaches the target threshold and how precisely that threshold can be characterized.
A reversal occurs when the adjustment direction changes, such as when a correct response follows an intensity increase or an incorrect response follows a decrease. Individual reversals show that the procedure is responding to the participant’s performance. Repeated reversals are important because their pattern indicates convergence near the selected performance threshold rather than a one-time response fluctuation.
The response rule determines how each answer changes the next stimulus. In the basic arrangement described here, an incorrect response increases intensity and a correct response decreases it, directing the sequence toward a chosen level of performance. Other predefined rules can produce different adjustment patterns, so the rule must match the threshold being estimated.
A typical task presents a stimulus, records the participant’s behavioral response, applies the predefined adjustment rule, and presents the next stimulus at the resulting level. The sequence continues across repeated trials, with intensity changing after each response. Researchers then examine the reversals and convergence pattern to estimate the selected performance threshold.
The principal outcome is an estimate of the stimulus level associated with a selected performance threshold. Interpretation depends on the adjustment history, including the direction of changes and the repeated reversals that produced convergence. The result can therefore serve as an index of sensory sensitivity or discrimination performance within the specific behavioral task.
A Psycho-physical Staircase reduces the number of trials needed to estimate sensory performance by adapting stimulus intensity to the participant’s responses. That efficiency makes it useful for studies of perception, attention, discrimination, and decision-making. Within behavior research, the method links observable choices to changes in stimulus level and supports individualized threshold measurement.