Deception is a complex and cognitively draining dyadic process that simultaneously involves cognitive and emotional processes, both of which demand/capture attentional resources. However, few studies have investigated the allocation of attentional resources between cognitive and emotional processes during deception. The current study presented facial expressions of different valences to 36 participants. While an electroencephalogram was recording, they were asked to make either truthful or deceptive gender judgments according to preceding cues. The results showed that deceptive responses induced smaller P300 amplitudes than did truthful responses. Task-irrelevant negative emotional information (TiN) elicited larger P300 amplitudes than did task-irrelevant positive emotional information (TiP). Furthermore, the results showed that TiN elicited larger LPP amplitudes than did TiP in deceptive responses, but not in truthful ones. The results suggested that attentional resources were directed away to deception-related cognitive processes and TiN, but not TiP, was consistently able to compete for and obtain attentional resources during deception. The results indicated that TiN could disrupt with deception and may facilitate deception detection.

Background: Smokers are more likely to report depressive symptoms, on the other hand, individuals with depression are also more likely to initiate smoking. In a recent study, higher CSF concentration of magnesium, zinc, iron, lead, lithium, and aluminum were reported among active smokers. This study investigated whether the disruption of central metal homeostasis in active smokers is associated with self-reports of depressive symptoms. Methods: CSF samples from 161 Chinese male patients who underwent anterior cruciate ligament reconstruction surgical operation following knee joint injuries were obtained. Among the 161 male patients, 57 male patients were active smokers while 104 patients reported never engaged in any form of smoking. Depressive symptoms were measured via Beck Depression Inventory (BDI) self-reports. CSF concentrations of 8 metal ions were quantified by atomic absorption spectrophotometry. Group comparisons, correlation analyses, mixed graphical model network analyses, and moderation models were performed to examine associations among smoking, CSF metal ions, and depressive symptoms. Results: Active smokers had higher BDI total scores and higher CSF concentrations of magnesium, zinc, iron, lead, lithium, and aluminum than non-smokers. Higher BDI total scores were associated with higher CSF concentration of zinc, iron, lead, and aluminum. Network analysis revealed iron, zinc, and lead ranked the highest in terms of strength, expected influence, and closeness among the 8 metal ions. With iron as an important association node among the three in the metal ion network observed, simultaneously significantly associated with BDI total scores. Further analyses revealed smoking was positively associated with depressive symptoms, and the interaction between smoking and iron significantly predicted BDI total scores. Additional analyses revealed that concentrations of iron in CSF also significantly interacted with zinc and lead. Conclusions: Iron is an important associated node that connects various other metal ions to self-reports of depressive symptoms. This finding shed light upon the interrelationships among smoking status, depressive symptoms, and metal ions in CSF, providing partial evidence supporting the relevance of central metal dysregulation to the smoking–depressive symptoms among male smokers.