Effects of a meaningful, a discriminative, and a meaningless stimulus on equivalence class formation

Thirty college students attempted to form three 3-node 5-member equivalence classes under the simultaneous protocol. After concurrent training of AB, BC, CD, and DE relations, all probes used to assess the emergence of symmetrical, transitive, and equivalence relations were presented for two test blocks. When the A-E stimuli were all abstract shapes, none of 10 participants formed classes. When the A, B, D, and E stimuli were abstract shapes and the C stimuli were meaningful pictures, 8 of 10 participants formed classes. This high yield may reflect the expansion of existing classes that consist of the associates of the meaningful stimuli, rather than the formation of the ABCDE classes, per se. When the A-E stimuli were abstract shapes and the C stimuli became S(D)s prior to class formation, 5 out of 10 participants formed classes. Thus, the discriminative functions served by the meaningful stimuli can account for some of the enhancement of class formation produced by the inclusion of a meaningful stimulus as a class member. A sorting task, which provided a secondary measure of class formation, indicated the formation of all three classes when the emergent relations probes indicated the same outcome. In contrast, the sorting test indicated "partial" class formation when the emergent relations test indicated no class formation. Finally, the effects of nodal distance on the relatedness of stimuli in the equivalence classes were not influenced by the functions served by the C stimuli in the equivalence classes.     

Equivalence class formation as a function of preliminary training with pictorial stimuli

The present experiment investigated the effects of preliminary training with pictorial stimuli on the subsequent formation of three 5‐member equivalence classes (A?B?C?D?E) in 84 university students assigned to seven groups of 12. In the Abstract (ABS) group, all stimuli were abstract shapes. In the Picture (PIC) group, the C stimuli were pictures, and the remaining stimuli were the same abstract shapes as in the ABS group. For the remaining five groups, all stimuli were the same abstract shapes as in the ABS group. However, across groups, preliminary training involved either the establishment of conditional relations with simultaneous (SMTS) or delayed (DMTS) matching‐to‐sample with 0 s, 3 s, 6 s, or 9 s between the abstract C stimuli and the meaningful pictures. For the ABS and the PIC groups, 16.7% and 83.3% of participants formed classes, respectively. Preliminary training with SMTS and DMTS with 0 s, 3 s, and 6 s produced a linear increase in the likelihood of equivalence class formation, 41.7%, 50%, and 75%, respectively. Increasing the duration of delay further from 6 s to 9 s produced a substantial decline, 50%. This experiment extends knowledge about how including meaningful pictures enhances equivalence class formation.     

The Role of Meaningful Stimuli in Large Stimulus Classes

The Psychological Record - The present experiment examined the effect of having the D-stimuli as meaningful pictures when establishing 18 conditional discriminations and testing for the emergence...     

Effects of mand-tact versus tact-only training on the acquisition of tacts

We sought to replicate and extend Carroll and Hesse's (1987) study of the acquisition of tacts by including participants with and without developmental disabilities. As in Carroll and Hesse, the present results showed that mand-tact training, rather than tact-only training, led to more rapid acquisition of tacts. Tacting on follow-up tests did not differ. In addition, our results show that mand-tact training established both verbal operants involved about as rapidly as tact-only training established only one verbal operant. DESCRIPTORS: verbal behavior, tact acquisition, mand-tact training, tact-only training, follow-up     

DISCRIMINATION LEARNING IN ADULTS WITH NEUROCOGNITIVE DISORDERS

Alzheimer's disease is the most commonly known neurocognitive disorder characterized by deterioration in areas such as memory, attention, and activities of daily living. From a behavioral perspective, memory and attentional deficits may be described as deterioration of stimulus control. This paper provides a case study of discrimination behavior in a patient with neurocognitive disorder. The purpose of the current study was twofold: (i) to study the effect of using presumed familiar pictures in arbitrary matching‐to‐sample tasks and (ii) to study variables that affect stimulus control in a patient diagnosed with vascular dementia. There were 12 conditional discrimination experimental conditions with various types of stimuli, from familiar pictures to identity matching. The results showed that the participant's responses were not in accord with experimenter‐defined stimulus classes when using familiar pictures. However, intact stimulus control by sample stimulus was established following systematic procedural changes in the conditional discrimination tasks. Copyright © 2014 John Wiley & Sons, Ltd.     

Effects of Training Structure and the Passage of Time on Trained and Derived Performance

The Psychological Record - Conditional discriminations established using a linear series training structure were shown in a previous study to be intact when unreinforced trials assessing such...