| Description |
The effects of the independent influences of emotional reactivity and cognitive processing on pupil diameter within the same experimental task were investigated. Pupil measurements included pupil diameter level, rate of recovery, and blink rate. All measurements were taken using both eyes to address possible effects of eye dominance. In the experiment, 40 participants (20% male) completed a modified Reading Span Task consisting of neutral and emotionally arousing stimuli, varied orthogonally. The stimuli were administered aurally to maximize pupil dilation differentials with memory loads ranging from one to three words. Participants were instructed to answer yes or no to factual statements along with remembering the last word of each statement. After one to three sentences, the participants were prompted to recall a specific word from the memory load, responses were given verbally. Main effects for cognitive load and emotional reactivity were observed during both the stimuli sentence processing phases and memory load recall phase. A main effect of load was observed for blink rate differences along with a main effect of content for differences in recovery rate. The findings also suggest an over-additive relationship between emotional reactivity (sympathetic) and cognitive processing (parasympathetic) influences on pupil diameter change, which was contrary to the predicted outcome. The evidence for this relationship was observed during trials of greatest cognitive demands, specifically the data for PD level during memory load recall. |
