Supine body posture reduces cognitive conflict processing: Evidence from N450 Stroop interference

Does effort increase or decrease reward valuation? Considerations from cognitive dissonance theory

The present research tested the effect of manipulated perceived control (over obtaining the outcomes) and effort on reward valuation using the event-related potential known as the Reward Positivity (RewP). This test was conducted in an attempt to integrate two research literatures with opposite findings: Effort justification occurs when high effort leads to high reward valuation, whereas effort discounting occurs when high effort leads to low reward valuation. Based on an examination of past methods used in these literatures, we predicted that perceived control and effort would interactively influence RewP. Consistent with the effort justification literature (cognitive dissonance theory), when individuals have high perceived control, high effort should lead to more reward valuation than low effort should. Consistent with the effort discounting literature, when individuals have low perceived control, low effort should lead to more reward valuation than high effort should. Results supported these interactive and integrative predictions.

Improved attention and performance monitoring in high procrastinating students after positive relative to negative norm-referenced feedback

Procrastination is an irrational delay of task completion. Previous studies have demonstrated that individuals who often procrastinate present deficits in attentional control and performance monitoring and that these dysfunctions might be differentially manifested depending on the motivational context. Building upon these results, the present event-related potential (ERP) study aimed to investigate the impact of norm-referenced feedback on executive functions among students with high (HP; N = 75) or low (LP; N = 77) procrastination levels. Participants completed the parametric Go/No-Go task, while receiving either positive or negative false feedback indicating how well they performed in comparison to others. The results indicated that positive (as opposed to negative) feedback led to higher self-reported arousal and increased post-error slowing in HP (vs. LP) participants. Moreover, neurophysiological measures indicated lower neural activation linked to attentional control (P300) and performance monitoring (ERN, CRN and Pe) in HP than LP participants, while the groups did not differ in these indices during the positive feedback condition. Obtained findings indicate that HP might be more sensitive to the motivating effects of success and more vulnerable to the detrimental influence of failure.

Facilitated extinction but impaired extinction recall by eye movement manipulation in humans - Indications for action mechanisms and the applicability of eye movement desensitization

Eye movement desensitization and reprocessing (EMDR) therapy utilizes the manipulation of eye movements to reduce affective distress during fear-exposure. Animal research recently suggested a potential neural mechanism underlying these effects, by which increased activity of the superior colliculus (SC), mediating visual attention, increases the inhibition of the basolateral amygdala (BLA), mediating defensive plasticity. We tested such mechanism in forty healthy humans using a multiple-day single-cue fear conditioning and extinction paradigm. The activity of the SC during extinction was experimentally manipulated by eye movements, as half of the participants executed saccadic eye movements (n = 20; major SC involvement), while the other half executed smooth eye pursuits (n = 20; minor SC involvement). Amygdala-mediated fear-potentiated startle responses and fear bradycardia, as well as threat expectancy was analyzed. Saccadic eye movements facilitated the extinction of fear bradycardia and fear-potentiated startle responses. Higher saccadic accuracy and range correlated with reduced fear-potentiated startle. However, during extinction recall, fear-potentiated startle and fear bradycardia resurged and partly reached levels obtained after fear acquisition. Threat expectancy was not affected by different eye movements and was not elevated during extinction recall. Within limitations, results support an inhibitory SC-BLA pathway in humans by which eye movements may reduce low-level defensive responding, but not threat expectancy. Yet, manipulating eye movements during extinction learning seems to impair extinction recall for behavioral and physiological defensive response indices. Thus, increasing SC activity might enhance initial efficacy of exposure treatment, but additional strategies seem necessary for sustained fear attenuation.