Introduction to the special research topic on the neurobiology of emotion-cognition interactions

The effects of emotional stimuli and oxytocin on inhibition ability and response execution in macaque monkeys

Social and emotional content of environmental stimuli influence executive control of behavior. There has been a great variability in the behavioral effects of emotional stimuli in humans. These variabilities might arise from other contextual factors, such as specific task demands or natural hormones, which potentially interact with emotional stimuli in modulating executive functions. This study aimed at examining the effects of social-emotional visual stimuli and a natural hormone (oxytocin) on inhibition ability and response execution of macaque monkeys. In a crossover design, monkeys received inhaled oxytocin or its vehicle before performing a stop-signal task in which they must respond rapidly to a visual go-cue in Go trials but inhibit the initiated response following the onset of a stop-cue in Stop trials. The social-emotional content (negative, positive or neutral) of the go-cue was changed trial-by-trial. We found that monkeys' inhibition ability was significantly influenced by the social-emotional content of stimuli and appeared as an enhanced inhibition ability when monkeys were exposed to negative stimuli. However, response execution was not influenced by the emotional content of stimuli in the current or preceding trials. The same dose of oxytocin, which modulated working memory in monkeys, had no significant effect on the inhibition ability, but significantly decreased monkeys' response time regardless of the stimulus valence. Our findings indicate that emotional stimuli, valence dependently, influence monkeys' inhibition ability but not their response execution and suggest that oxytocin might attenuate reorientation of cognitive resources to the task irrelevant emotional information.

Mutual influence between emotional language and inhibitory control processes. Evidence from an event-related potential study

There is abundant literature demonstrating that processing emotional stimuli modulates inhibitory control processes. However, the reverse effects, namely, how cognitive inhibition influences the processing of emotional stimuli, have been considerably neglected. This ERP study tries to fill this gap by studying the bidirectional interactions between emotional language and inhibitory processes. To this end, participants read emotional sentences, embedded in a cue-based Go-NoGo task. In Experiment 1, the critical emotional adjective preceded the Go-NoGo visual cue. The ERPs showed a significant reduction in the inhibition-related N2 component in NoGo trials when they were preceded by negative adjectives, compared to positive or neutral adjectives, indicating a priming-like effect on inhibitory control. Consistently, the estimated source of this interaction was the dorsomedial PFC, a region associated with inhibitory and control processes. In Experiment 2, the Go-NoGo cue preceded the emotional adjective, and the ERPs showed a sustained, broadly distributed LPP-like positivity for NoGo negative trials, relative to all the other conditions. In this case, the presetting of an inhibition state modulated the processing of negatively charged words. Together, the two experiments suggest a mutual facilitation between inhibitory control and negative valence, supporting thereby recent integrative theories of cognition-emotion interactions.

The neurobiology of emotion-cognition interactions: fundamental questions and strategies for future research

Recent years have witnessed the emergence of powerful new tools for assaying the brain and a remarkable acceleration of research focused on the interplay of emotion and cognition. This work has begun to yield new insights into fundamental questions about the nature of the mind and important clues about the origins of mental illness. In particular, this research demonstrates that stress, anxiety, and other kinds of emotion can profoundly influence key elements of cognition, including selective attention, working memory, and cognitive control. Often, this influence persists beyond the duration of transient emotional challenges, partially reflecting the slower molecular dynamics of catecholamine and hormonal neurochemistry. In turn, circuits involved in attention, executive control, and working memory contribute to the regulation of emotion. The distinction between the 'emotional' and the 'cognitive' brain is fuzzy and context-dependent. Indeed, there is compelling evidence that brain territories and psychological processes commonly associated with cognition, such as the dorsolateral prefrontal cortex and working memory, play a central role in emotion. Furthermore, putatively emotional and cognitive regions influence one another via a complex web of connections in ways that jointly contribute to adaptive and maladaptive behavior. This work demonstrates that emotion and cognition are deeply interwoven in the fabric of the brain, suggesting that widely held beliefs about the key constituents of 'the emotional brain' and 'the cognitive brain' are fundamentally flawed. We conclude by outlining several strategies for enhancing future research. Developing a deeper understanding of the emotional-cognitive brain is important, not just for understanding the mind but also for elucidating the root causes of its disorders.