Incidental learning of faces during threat: No evidence for enhanced physiological responses to former threat identities.

Remembering an unfamiliar person and the contextual conditions of that encounter is important for adaptive future behavior, especially in a potentially dangerous situation. Initiating defensive behavior in the presence of former dangerous circumstances can be crucial. Recent studies showed selective electrocortical processing of faces that were previously seen in a threat context compared to a safety context, however, this was not reflected in conscious recognition performance. Here, we investigated whether previously seen threat-faces, that could not be remembered, were capable to activate defensive psychophysiological response systems. During an encoding phase, 50 participants with low to moderate levels of anxiety viewed 40 face pictures with neutral expressions (6 s each), without an explicit learning instruction (incidental learning task). Each half of the faces were presented with contextual background colors that signaled either threat-of-shock or safety. In the recognition phase, all old and additional new faces (total of 60) were presented intermixed without context information. Participants had to decide whether a face was new or had been presented previously in a threatening or a safe context. Results show moderate face recognition independent of context conditions. Startle reflex and skin conductance responses (SCR) were more pronounced for threat compared to safety during encoding. For SCR, this differentiation was enhanced with higher levels of depression and anxiety. There were no differential startle reflex or SCR effects during recognition. From a clinical perspective, these findings do not support the notion that perceptual biases and physiological arousal directly relate to threat-associated identity recognition deficits in healthy and clinical participants with anxiety and trauma-related disorders.

A multinomial modelling approach to face identity recognition during instructed threat.

To organise future behaviour, it is important to remember both the central and contextual aspects of a situation. We examined the impact of contextual threat or safety, learned through verbal instructions, on face identity recognition. In two studies (N = 140), 72 face-context compounds were presented each once within an encoding session, and an unexpected item/source recognition task was performed afterwards (including 24 new faces). Hierarchical multinomial processing tree modelling served to estimate individual parameters of item (face identity) and source memory (threat or safety context) as well as guessing behaviour. Results show that language was highly effective in establishing threatening and safe context conditions. In Study 1, a fleeting picture stream (1 s per picture) led to poor item and source recognition. Prolonged presentation times (Study 2 with 6 s per picture) improved face memory but no contextual modulation was observed. Thus, incidental face learning was surprisingly poor and rapidly changing contextual settings might have interfered with the accurate encoding of face identity information and item-source binding.

Help or flight? Increased threat imminence promotes defensive helping in humans.

In humans and other mammals, defensive responses to danger vary with threat imminence, but it is unknown how those responses affect decisions to help conspecifics. Here, we manipulated threat imminence to investigate the impact of different defensive states on human helping behaviour. Ninety-eight healthy adult participants made trial-by-trial decisions about whether to help a co-participant avoid an aversive shock, at the risk of receiving a shock themselves. Helping decisions were prompted under imminent or distal threat, based on temporal distance to the moment of shock administration to the co-participant. Results showed that, regardless of how likely participants were to also receive a shock, they helped the co-participant more under imminent than distal threat. Reaction times and cardiac changes during the task supported the efficacy of the threat imminence manipulation in eliciting dissociable defensive states, with faster responses and increased heart rate during imminent compared to distal threats. Individual differences in empathic concern were specifically correlated with helping during imminent threats. These results suggest that defensive states driving active escape from immediate danger may also facilitate decisions to help others, potentially by engaging neurocognitive systems implicated in caregiving across mammals.

Contextual source information modulates neural face processing in the absence of conscious recognition: A threat-of-shock study.

Often the source of information is as important as the information itself. The present study examined the impact of contextual threat and safety signals (source information) on memory encoding and recognition of faces (item information). In two experimental sessions, 30 participants viewed neutral face pictures. In the encoding session, 60 faces were presented with contextual background colors (blue or green, 30 pictures each) which were verbally instructed to signal either threat-of-shock or safety. In the recognition session, the 60 old faces intermixed with 30 new faces were shown while a combined old/new recognition and source memory task was performed. During the encoding session, face processing varied as a function of contextual source information. Confirming successful threat-of-shock manipulation, threatening compared to safe face-context compounds revealed differential neural processing (early parieto-occipital and late fronto-central negativity) as well as pronounced threat ratings. During the recognition session, participants had serious problems identifying old from new faces with poor source memory. Intriguingly, however, brain activity differentiated previously seen faces from newly presented pictures (old/new ERP effect). Moreover, old faces presented within a threat context were associated with distributed late negativities compared to old safe faces. Thus, threat effects not only emerged during face encoding (incidental learning) but also during face recognition, although no valid judgements could be made regarding the threatening or safe sources. These findings support the notion that contextual source information critically modulates person perception and recognition as a form of an expectation based remembering in the absence of conscious recognition.

The mere sight of loved ones does not inhibit psychophysiological defense mechanisms when threatened.

Looking at pictures of loved ones, such as one's romantic partner or good friends, has been shown to alleviate the experience of pain and reduce defensive reactions. However, little is known about such modulatory effects on threat and safety learning and the psychophysiological processes involved. Here, we explored the hypothesis that beloved faces serve as implicit safety cues and attenuate the expression of fear responses and/or accelerate extinction learning in a threatening context. Thirty-two participants viewed pictures of their loved ones (romantic partner, parents, and best friend) as well as of unknown individuals within contextual background colors indicating threat-of-shock or safety. Focusing on the extinction of non-reinforced threat associations (no shocks were given), the experiment was repeated on two more test days while the defensive startle-EMG, SCR, and threat ratings were obtained. Results confirmed pronounced defensive responding to instructed threat-of-shock relative to safety context (e.g., threat-enhanced startle reflex and SCR). Moreover, threat-potentiated startle response slowly declined across test days indicating passive extinction learning in the absence of shocks. Importantly, neither a main effect of face category (loved vs. unknown) nor a significant interaction with threat/safety instructions was observed. Thus, a long-term learning history of beneficial relations (e.g., with supportive parents) did not interfere with verbal threat learning and aversive apprehensions. These findings reflect the effects of worries and apprehensions that persist despite the repeated experience of safety and the pictorial presence of loved ones. How to counter such aversive expectations is key to changing mal-adaptive behaviors (e.g., avoidance or stockpiling), biased risk perceptions, and stereotypes.

Social threat and safety learning in individuals with adverse childhood experiences: electrocortical evidence on face processing, recognition, and working memory.

Background: Adverse childhood experiences (ACEs) are often associated with stress and anxiety-related disorders in adulthood, and learning and memory deficits have been suggested as a potential link between ACEs and psychopathology. Objective: In this preregistered study, the impact of social threat learning on the processing, encoding, and recognition of unknown faces as well as their contextual settings was measured by recognition performance and event-related brain potentials. Method: Sixty-four individuals with ACEs encoded neutral faces within threatening or safe context conditions. During recognition, participants had to decide whether a face was new or had been previously presented in what context (item-source memory), looking at old and new faces. For visual working memory, participants had to detect changes in low and high load conditions during contextual threat or safety. Results: Results showed a successful induction of threat expectation in persons with ACEs. In terms of face and source recognition, overall recognition of safe and new faces was better compared to threatening face-compounds, with more socially anxious individuals having an advantage in remembering threatening faces. For working memory, an effect of task load was found on performance, irrespective of threat or safety context. Regarding electrocortical activity, an old/new recognition effect and threat-selective processing of face-context information was observed during both encoding and recognition. Moreover, neural activity associated with change detection was found for faces in a threatening context, but only at high task load, suggesting reduced capacity for faces in potentially harmful situations when cognitive resources are limited. Conclusion: While individuals with ACE showed intact social threat and safety learning overall, threat-selective face processing was observed for item/source memory, and a threatening context required more processing resources for visual working memory. Further research is needed to investigate the psychophysiological processes involved in functional and dysfunctional memory systems and their importance as vulnerability factors for stress-related disorders.

Antecedentes: Las experiencias adversas en la infancia (ACEs, por su sigla en inglés) estan a menudo asociadas con trastornos relacionados con el estrés y la ansiedad en la edad adulta, y los déficits de aprendizaje y memoria han sido sugeridos como un vínculo potencial entre las ACEs y la psicopatología.Objetivo: En este estudio previamente registrado, el impacto del aprendizaje de amenazas sociales en el procesamiento, la codificación y el reconocimiento de rostros desconocidos, así como sus entornos contextuales, se midió mediante el rendimiento y los potenciales cerebrales relacionados con los eventos.Método: Sesenta y cuatro personas con ACEs codificaron rostros neutrales dentro de condiciones de contextos amenazantes o seguros. Durante el reconocimiento, los participantes tenían que decidir si una cara era nueva o se había presentado previamente en qué contexto (elemento-fuente de memoria), mirando caras antiguas y nuevas. Para la memoria de trabajo visual, los participantes tenían que detectar cambios en las condiciones de carga baja y alta durante la amenaza contextual o la seguridad.Resultados: Los resultados mostraron una inducción exitosa de la expectativa de amenaza en personas con ACEs. En términos de reconocimiento de rostros y fuentes, el reconocimiento general de rostros seguros y nuevos fue mejor en comparación con los compuestos de rostros amenazantes, y las personas más ansiosas socialmente tenían una ventaja para recordar rostros amenazantes. Para la memoria de trabajo, se encontró un efecto de la carga de tareas en el rendimiento, independientemente de la amenaza o el contexto de seguridad. Con respecto a la actividad electrocortical, se observó un efecto de reconocimiento antiguo/nuevo y un procesamiento selectivo de amenazas de la información del contexto facial durante la codificación y el reconocimiento. Además, se encontró actividad neuronal asociada con la detección de cambios para rostros en un contexto amenazante, pero solo con una gran carga de tareas, lo que sugiere una capacidad reducida para rostros en situaciones potencialmente dañinas cuando los recursos cognitivos son limitados.Conclusión: Si bien las personas con ACE mostraron un aprendizaje intacto de amenazas sociales y seguridad en general, se observó un procesamiento facial selectivo de amenazas para la memoria de elementos/fuentes, y un contexto amenazante requería más recursos de procesamiento para la memoria de trabajo visual. Se necesita más investigación para investigar los procesos psicofisiológicos involucrados en los sistemas de memoria funcional y disfuncional y su importancia como factores de vulnerabilidad para los trastornos relacionados con el estrés.

Aversive anticipations modulate electrocortical correlates of decision-making and reward reversal learning, but not behavioral performance.

Predicting the consequences of one's own decisions is crucial for organizing future behavior. However, when reward contingencies vary frequently, flexible adaptation of decisions is likely to depend on the situation. We examined the effects of an instructed threat context on choice behavior (i.e., reversal learning) and its electrocortical correlates. In a probabilistic decision-making task, 30 participants had to choose between two options that were either contingent on monetary gains or losses. Reward contingencies were reversed after reaching a probabilistic threshold. Decision-making and reversal learning were examined with two contextual background colors, which were instructed as signals for threat-of-shock or safety. Self-report data confirmed the threat context as more unpleasant, arousing, and threatening relative to safety condition. However, against our expectations, behavioral performance was comparable during the threat and safety conditions (i.e., errors-to-criterion, number of reversal, error rates, and choice times). Regarding electrocortical activity, feedback processing changed throughout the visual processing stream. The feedback-related negativity (FRN) reflected expectancy-driven processing (unexpected vs. congruent losses and gains), and the threat-selective P3 component revealed non-specific discrimination of gains vs. losses. Finally, the late positive potentials (LPP) showed strongly valence-specific processing (unexpected and congruent losses vs. gains). Thus, regardless of contextual threat, early and late cortical activity reflects an attentional shift from expectation- to outcome-based feedback processing. Findings are discussed in terms of reward, threat, and reversal-learning mechanisms with implications for emotion regulation and anxiety disorders.