Stimulus Over-selectivity: An Investigation of Extinction Effects and Correlates across Populations
Kelly, Michelle Patricia
MetadataShow full item record
This item's downloads: 565 (view details)
This thesis examined stimulus over-selectivity, a phenomenon where only a limited subset of the total number of stimuli present during discrimination learning controls behaviour. Stimulus over-selectivity is a widely acknowledged problem for an individual's functioning because it limits learning in situations consisting of multiple and complex cues. This research experimentally demonstrated over-selectivity in both clinical and non-clinical populations, using a discrete trial discrimination paradigm. It investigated the remediating effects of stimulus over-selectivity by manipulating post-learning behaviour by extinguishing the over-selected stimuli. This research examined the correlation between stimulus over-selectivity and several variables, including: attention, cognitive flexibility, behavioural flexibility, stereotyped behaviour, IQ, mental age, chronological age, and severity of autism diagnosis. Chapters 2 and 3 investigated stimulus over-selectivity in children and adolescents with Autistic Spectrum Conditions (ASC). Chapter 2 examined the effects of level of functioning on degree of over-selective responding. Extinction was investigated as a potential remediation strategy for stimulus over-selectivity. Chapter 3 explored the correlation between stimulus over-selectivity and inflexibility, attention, and stereotyped behaviour to extend the theoretical framework of the concept. Chapter 4 examined stimulus over-selectivity in typically developing children aged three to seven years. An extinction procedure was employed to test the effects on the previously over-selected and under-selected stimuli, and to evaluate its potential to act as an effective remediation strategy. Chapter 4 also investigated correlations between cognitive flexibility and selective attention with over-selectivity in this non-clinical population. In Chapter 5, extinction was employed to demonstrate its effects on post-test levels of over-selectivity in three age groups of typically developing elderly individuals. This chapter also analysed chronological age, cognitive flexibility and attention levels as correlates of over-selectivity. The results from the current thesis are discussed in terms of theoretical perspectives of stimulus over-selectivity, and implications for potential remediation strategies.
This item is available under the Attribution-NonCommercial-NoDerivs 3.0 Ireland. No item may be reproduced for commercial purposes. Please refer to the publisher's URL where this is made available, or to notes contained in the item itself. Other terms may apply.
The following license files are associated with this item: