The measurement of impulsivity
The focus of this thesis is the much debated construct of impulsivity, exploring its meaning, etiology and measurement. The literature review provides a background for the empirical papers, by examining the theoretical underpinnings of impulsivity, from which a plethora of measuring instruments have been generated. The review explores the difficulties associated with measuring a contrast which has little consensus over its components, and highlights studies which have attempted to draw together a common understanding of the construct. The main paper provides a useful exploration of four widely used self-report measures of impulsivity, investigating whether the measures examine similar or different facets of impulsivity. The results demonstrate the lack of congruity between the measures, suggesting that two of the measures appear to tap a common construct, whereas the remaining two measure only a narrow construct and raise questions about its validity. The brief paper is a pilot study drawing upon a visual search paradigm to investigate the Attentional Fixity theory of impulsivity, arousal and performance among a sexual offending sample. The findings although tentative, failed to support the hypothesis that arousal improves performance in a cognitive task. Instead it was found that performance decreased when individuals were presented with sexual stimuli. The findings also fail to support the hypothesis that high impulsivity is associated with an inability to fix attention on a source of input. This suggest that the current sample of sexual offenders, as a high impulsive group tend to fix their attention on sexual stimuli and become distracted from other cognitive demands. Finally, the reflective review explores further findings from the empirical papers, reflecting upon methodological, ethical and conceptual issues.