Shifts in Postdiscrimination Gradients Within a Stimulus Dimension Based on Female Waist-to-Hip Ratios

Abstract

Fifteen participants were trained on a within-subjects basis with two discrimination training conditions and one simple generalization training (control) condition to determine whether gradient shifts can be obtained within a stimulus dimension consisting of women’s waist-to-hip ratios (WHRs). In one discrimination condition, the S− consisted of the “optimal” WHR; in the other, the S− consisted of the approximate mean WHR for adult women. For all three conditions, the S+ was an intermediate value. Under both discrimination training conditions, the generalization gradient was observed to shift away from the S− and toward extreme values on the opposite end of the dimension; under the control condition, the gradient was more closely centered on the S+. The results suggest that the processes involved in gradient shifts can affect judgments of biologically significant stimuli.