Abstract
At present, there is no clear demonstration of equivalence class formation in elderly participants with neurocognitive disorders. We attempted to establish equivalence classes with a patient with Alzheimer’s disease, starting with relations maintained in her repertoire, so that she could learn by exclusion. After baseline training she acquired arbitrary conditional discriminations and tests suggested the emergence of symmetry and transitivity. Inclusion of a third comparison disrupted performance. Some methodological aspects of this exploratory study may contribute to future research with this particularly challenging population.