Spatial Perception and Inhibition of Emotional vs. Visual Cues of Threatening Stimuli

Abstract

Attention is rapidly drawn to threatening stimuli. A longstanding debate in the field revolves around whether the root cause of this bias is primarily attributable to the affective aspects (e.g., Fear Module Theory) or the general features (e.g., General Feature Detection Theory) of said stimuli. Additionally, there is an ongoing debate (Attention Capture Debate) that revolves around the mechanisms by which salient stimuli seize our attention. Some theories suggest that salient stimuli will always capture attention automatically (stimulus-driven attention), while on the other hand, some suggest that these stimuli can be ignored when irrelevant to our goals (goal-driven attention). There are many factors that may influence the interaction between these processes, such as physical features of the salient object or the presentation time and – place of the object. Additionally, the Signal Suppression Hypothesis suggests that it is possible to suppress the processing of visually salient stimuli before attentional capture happens. Ensuring a robust foundation for our research, we conducted a systematic review on the topic of the perception and inhibition of salient stimuli. Then, throughout a series of three experiments that employ a combination of visual search and vigilance tasks, we led investigations, grounded in the collection of behavioural measures, encompassing response times and accuracy, coupled with insights derived from eye-tracking technology. Furthermore, it is important to emphasise that our choice of healthy young adult participants is intentional, as our research primarily focuses on examining the fundamental mechanisms of attention. The main finding of the dissertation is that negative stimuli, when presented as distractors, are exceptionally challenging to inhibit. In the far condition task performance exhibited a noticeable decline when threatening distractors were presented, compared to nonthreatening or neutral distractors. Surprisingly, we observed that the presentation of threatening stimuli could lead to improved task performance when appearing close to the task, with no significant difference between nonthreatening or neutral stimuli and threatening stimuli. This enhancement in performance may be attributed to the arousal stimulation effect.