Ascending-descending threshold difference and internal subjective judgment in CFF measurements of depressed patients before and after clinical improvement

The purpose of this study was to measure, using the method of limits, the ascending-descending threshold difference, Δ = fa - fd, in subjects with major depression. 28 patients were given two sessions, one before treatment and the other after recovery. Mean values of Δ measured in the second session were significantly smaller than those scored before treatment. The two sets of values were positively correlated. The ascending-descending threshold difference was suggested previously as likely related to the internal subjective judgment of subjects. The present results are consistent with the hypothesis of a more conservative response criterion in depressed patients before than after clinical improvement.