BackgroundA growing set of studies has shown a positive relationship between aerobic fitness and a broad array of cognitive functions. However, few studies have focused on sustained attention, which has been considered a fundamental cognitive process that underlies most everyday activities. The purpose of this study was to investigate the role of aerobic fitness as a key factor in sustained attention capacities in young adults.MethodsForty-four young adults (18–23 years) were divided into two groups as a function of the level of aerobic fitness (high-fit and low-fit). Participants completed the Psychomotor Vigilance Task (PVT) and an oddball task where they had to detect infrequent targets presented among frequent non-targets.ResultsThe analysis of variance (ANOVA) showed faster responses for the high-fit group than for the low-fit group in the PVT, replicating previous accounts. In the oddball task, the high-fit group maintained their accuracy (ACC) rate of target detection over time, while the low-fit group suffered a significant decline of response ACC throughout the task.DiscussionImportantly, the results show that the greater sustained attention capacity of high-fit young adults is not specific to a reaction time (RT) sustained attention task like the PVT, but it is also evident in an ACC oddball task. In sum, the present findings point to the important role of aerobic fitness on sustained attention capacities in young adults.

Significant others provide individuals with a sense of safety and security. However, the mechanisms that underlie attachment-induced safety are hardly understood. Recent research has shown beneficial effects when viewing pictures of the romantic partner, leading to reduced pain experience and defensive responding. Building upon this, we examined the inhibitory capacity of loved face pictures on fear learning in an instructed threat paradigm. Pictures of loved familiar or unknown individuals served as signals for either threat of electric shocks or safety, while a broad set of psychophysiological measures was recorded. We assumed that a long-term learning history of beneficial relations interferes with social threat learning. Nevertheless, results yielded a typical pattern of physiological defense activation towards threat cues, regardless of whether threat was signaled by an unknown or a loved face. These findings call into question the notion that pictures of loved individuals are shielded against becoming threat cues, with implications for attachment and trauma research.

The neuroscientific study of love has been boosted by an extended corpus of research on face-identity recognition. However, few studies have compared the emotional mechanisms activated by loved faces and names and none have simultaneously examined fMRI and autonomic measures. The present study combined fMRI with the heart rate response when 21 participants (10 males) passively viewed the face or the written name of 4 loved people and 4 unknown people. The results showed accelerative patterns in heart rate, together with brain activations, which were significantly higher for loved people than for unknown people. Significant correlations were found between heart rate and brain activation in frontal areas, for faces, and in temporal areas, for names. The results are discussed in the context of previous studies using the same passive viewing procedure, highlighting the relevance of integrating peripheral and central measures in the scientific study of positive emotion and love.

Recent studies on fear conditioning and pain perception suggest that pictures of loved ones (e.g., a romantic partner) may serve as a prepared safety cue that is less likely to signal aversive events. Challenging this view, we examined whether pictures of smiling or angry loved ones are better safety or threat cues. To this end, 47 healthy participants were verbally instructed that specific facial expressions (e.g., happy faces) cue threat of electric shocks and others cue safety (e.g., angry faces).When facial images served as threat cues, they elicited distinct psychophysiological defensive responses (e.g., increased threat ratings, startle reflex, and skin conductance responses) compared to viewing safety cues. Interestingly, instructed threat effects occurred regardless of the person who cued shock threat (partner vs. unknown) and their facial expression (happy vs. angry). Taken together, these results demonstrate the flexible nature of facial information (i.e., facial expression and facial identity) to be easily learned as signals for threat or safety, even when showing loved ones.