ABSTRACT
This paper discusses recent methodological approaches and investigations that are aimed at developing reliable behavioral technology for teaching stimulus–stimulus relations to individuals who are minimally verbal and show protracted difficulty in acquiring such relations. The paper has both empirical and theoretical contents. The empirical component presents recent data concerning the possibility of generating rapid relational learning in individuals who do not initially show it. The theoretical component (1) considers decades of methodological investigations with this population and (2) suggests a testable hypothesis concerning some individuals who exhibit unusual difficulties in learning. Given this background, we suggest a way forward to better understand and perhaps resolve these learning challenges.
Acknowledgments
Special thanks yet again to Iver Iversen, Per Holth, Erik Arntzen, and the many others who contributed to the 2014 event in Sarasota, Fl that allowed us to again honor Murray Sidman for his past and continuing professional and personal contributions to all of our lives.
Disclosure statement
No potential conflict of interest was reported by the authors.
Notes
1. The term minimally verbal seems to have largely replaced the term nonverbal when describing this population, perhaps because few individuals exhibit a total absence of verbal behavior. The newer term is intended to convey that the individual’s functional verbal repertoire is extremely limited when contrasted with repertoires of typical individuals of a similar age.
2. Sidman and Cresson (Citation1973) published an early study of stimulus equivalence class formation that demonstrated the very slow learning that concerns us here. That study did show equivalence class formation in minimally verbal individuals, truly remarkable findings at that time. However, those findings were obtained only after very lengthy, painstaking discrimination training. One participant required nearly a year of training before he was ready for basic equivalence tests.
3. Stimulus control shaping (McIlvane & Dube, Citation1992) is typically used to refer to methods that use graduated, progressive stimulus changes over trials to prompt correct selections (i.e., stimulus shaping, stimulus fading, progressive delayed prompting, etc.).
4. As Sidman (Citation1987) reminds us, positive results on two-comparison tests do not necessarily imply that the participant has learned both sample:comparison relations. For example, such performance could result from learning merely the A1:B1 relation and selecting the B2 comparison in relation to the A2 sample via exclusion of B1.