Deprivation and reward stimuli as compound stimuli

In Experiment 1 the experimental group was tested with a deprivation level and a reward magnitude which it had experienced previously but which it had not experienced in combination. This group was inferior in test performance to a group which had experienced the test deprivation-reward combination prior to test. These results were interpreted as indicating that deprivation stimuli and reward stimuli form a compound stimulus and training on the elements of the compound produces performance inferior to training directly on the compound. In Experiment 2, the decrement associated with two different shifts in deprivation and reward did not differ despite the different size change of total incentive involved in the two shifts. The results were interpreted as indicating that the deprivation-reward stimulus is not produced by a single underlying incentive mechanism.     

Short-term memory,verbal competence,and age as predictors of imagery instructional effectiveness

Children 6 to 11 years of age heard concrete sentences that they were asked to learn. Half the subjects were instructed to construct images representing the sentence meanings. The remaining participants were provided no strategy instructions (control condition). Consistent with previous outcomes, the older children in the imagery condition learned signficantly more than did the older control subjects. There was a slight trend favoring imagery for younger children in the sample. Individual differences in short-term memory and verbal competence were more highly associated with performance in the imagery than in the control condition, such that greater short-term memory and verbal competence predicted better sentence learning in the imagery condition. In particular, short-term memory and verbal competence made unique contributions (relative to age and to each other) to prediction of sentence learning in the imagery condition, but not in the control condition. In short, imagery instruction is more effective with children who are more intellectually competent.     

Instructions as discriminative stimuli

Four undergraduates were exposed to a fixed-ratio schedule under an instruction to respond slowly and to a differential-reinforcement-of-low-rate 5-s schedule under an instruction to respond rapidly. Following this, a fixed-interval schedule was in effect under those same two sets of instructions. For 3 of 4 subjects, response rates were higher with the instruction to respond slowly than with the instruction to respond rapidly during the fixed-interval schedule. For the remaining subject, low-rate responding with the instruction to respond rapidly continued during the first 17 reinforcements of the fixed-interval schedule. Such control by instructions was not observed for other subjects exposed only to a fixed-interval schedule, with or without instructions. The results demonstrate that the effect of instructions can be altered by contingencies and suggest that instructions can function as discriminative stimuli.     

Reinforcement contingencies as discriminative stimuli

A matching paradigm was used to examine the discriminative properties of two different reinforcement contingencies. Responding according to either a differential-reinforcement-of-low-rate or a differential-reinforcement-of-other-behavior schedule produced a choice situation in which each of two keys was illuminated with a unique color. The correct choice response was defined by the contingency that was met to produce the choice. Eighty to 100% correct matching was obtained and recovered during two reversals of the choice stimuli. Introduction of a delay between completion of the reinforcement contingency and presentation of the choice stimuli resulted in decrements in matching performances similar to those obtained when other types of sample stimuli are used. The results provided evidence of the discriminative properties of the relation between behavior and other classes of stimuli.     

Tilted lines as complex stimuli

Severely retarded boys were taught to respond differentially to lines tilted at 45 degrees and 135 degrees . While all subjects could perform the discrimination, the aspect of the stimulus that controlled responding was shown to differ among subjects.     

Conflict performance as a function of instructional set and absolute strength

One-hundred-twenty-eight male and female introductory psychology students performed in a conflict task. It was found that neither prior knowledge of the “correct” response nor number of practice trials prior to the conflict trial (8 versus 24) had differential effects on performance on the conflict trial. However, subjects who were shocked following an incorrect response took longer to make a decision on the conflict trial than subjects who were not shocked, and females took significantly longer than males.