Responder por exclusão em treinos de discriminação condicional com estímulos temporais por universitários

Abstract

Choose by exclusion has been extensively investigated and documented in different human populations. The pattern of conditional discrimination of an undefined stimulus obtained for an undefined model when possible experimentally defined choices exist has attracted the attention of researchers interested in symbolic processes such as vocabulary acquisition. Studies employing concrete stimuli have generated compelling data at the same time that they have also highlighted the need for refining knowledge about the properties of the stimuli controlling the response. The utilization of a onedimensional stimulus, like time, could add empirical data about the exact moment when the participant starts to see the undefined stimulus as being different from those used during training. Temporal stimuli have been applied in many investigations of temporal perception. In this context, this work aims to verify how university students respond to exclusion tasks and generalization tests using temporal stimuli as the stimulus mode,on the basis of double temporal bisection trainings. Forty-four university students aged between 18 and 26 years participated in this study, conducted under four different experimental conditions. For the first condition, training consisted in the formation of two conditionals between stimuli lasting 0.5 and 2 seconds for the colors red and green (first bisection), and the relation between stimuli lasting 2 and 8 seconds for the colors blue and yellow (second bisection).For the second condition, the model stimuli lasted 0.3 and 1.2 seconds for red and green, and 1.2 and 4.8for blue and yellow. Models with even shorter duration were utilized for the third and fourth conditions, 0.2 and 0.6,and 0.6 and 1.8 seconds for red and green, and blue and yellow, respectively. The other difference between the conditions lay on the stimulus mode; i.e., visual (time during which a black square remained on the screen) for the first three conditions, and auditory (time during which a beep could be heard) for the last condition. Once the baseline was established, we conducted five blocks of generalization tests with attempts consisting in the presentation of model stimuli lasting for a time period different from the trained periods and undefined and defined comparison stimuli (colors). The generalization test results revealed that the preference for red diminished with longer stimuli, and that the preference for yellow followed an inverse trend. Compared with blue, the choice of green was more frequent during shorter time intervals. As for the Exclusion Test, there was preference for defined stimuli compared with stimuli closer to the trained ones and for undefined stimuli compared with periods less close to the trained ones. These findings contribute to the investigation of responding by exclusion, since there is preference for the undefined stimulus compared with models never seen previously, especially if the models are distant from the trained ones. The generalization data differed from those achieved for non-humans, which opens a discussion about temporal discrimination learning and the role of verbalization and counting.