| dc.description.abstract | Underpinned by the Behavioural Approach System (BAS) dysregulation theory of bipolar disorder (BD), five studies were conducted in non-clinical samples to; refine the measurement of state Approach Motivation (AM); measure minor increases in AM; and then finally, to investigate how this relates to attentional biases for emotional stimuli.
Study 1 attempted to clarify the phenomenology of state AM and revealed four separable factors that emerged from pooled AM questionnaire items. These structures loosely mapped on hypothesized components of the BAS (Depue & Iacono, 1989) that pertain to; cognitive elements of approach motivation (feeling determined and inspired); an energized, activated state; an affective structure relating to positive mood and outlook; and finally to feelings of excitement. Studies 2 and 3 investigated the validity of the four derived factors and their parent scales against a reward-oriented laboratory induction, a psychophysiological marker of AM, and a test of the discriminative power. The validity results suggested that the most well-established of the scales, the PANAS-PA, slightly outperformed the other measures by showing the greatest response to an AM induction. A second aim was to explore the substructure of a valid measure of mania risk - the hypomanic personality scale (HPS: Eckblad & Chapman, 1986) – in relation to AM responsivity. Unexpectedly, individuals who endorsed unpredictable and changeable moods (mood volatility) displayed elevated sympathetic arousal in response to control task.
On this basis, and with a view to exploring the role selective attentional processes as a mediator of AM dysregulation that is relevant to bipolar disorder, study 4 and 5 utilised PANAS-PA to replicate a bi-directional congruency-effect found in the literature between elevations in AM and attentional information-processing biases to reward-related stimuli. Results in general did not support a causal influence of AM on attentional biases, nor did the attempted manipulation of attentional biases affect downstream AM. However, there was evidence that within a stratified sample of participants who reliably responded to the AM and control conditions, those at greater risk to mania exhibited an attentional bias for both positive and negative stimuli, relative those at lower risk to mania. | en_GB |
