Dissociating representations of affect and motion in visual cortices.

While a delicious dessert being presented to us may elicit strong feelings of happiness and excitement, the same treat falling slowly away can lead to sadness and disappointment. Our emotional response to the item depends on its visual motion direction. Despite this importance, it remains unclear whether (and how) cortical areas devoted to decoding motion direction represents or integrates emotion with perceived motion direction. Motion-selective visual area V5/MT+ sits, both functionally and anatomically, at the nexus of dorsal and ventral visual streams. These pathways, however, differ in how they are modulated by emotional cues. The current study was designed to disentangle how emotion and motion perception interact, as well as use emotion-dependent modulation of visual cortices to understand the relation of V5/MT+ to canonical processing streams. During functional magnetic resonance imaging (fMRI), approaching, receding, or static motion after-effects (MAEs) were induced on stationary positive, negative, and neutral stimuli. An independent localizer scan was conducted to identify the visual-motion area V5/MT+. Through univariate and multivariate analyses, we demonstrated that emotion representations in V5/MT+ share a more similar response profile to that observed in ventral visual than dorsal, visual structures. Specifically, V5/MT+ and ventral structures were sensitive to the emotional content of visual stimuli, whereas dorsal visual structures were not. Overall, this work highlights the critical role of V5/MT+ in the representation and processing of visually acquired emotional content. It further suggests a role for this region in utilizing affectively salient visual information to augment motion perception of biologically relevant stimuli.

The psychophysiology of guilt in healthy adults.

Guilt is a negative emotion, elicited by realizing one has caused actual or perceived harm to another person. Anecdotally, guilt often is described as a visceral and physical experience. However, while the way that the body responds to and contributes to emotions is well known in basic emotions, little is known about the characteristics of guilt as generated by the autonomic nervous system. This study investigated the physiologic signature associated with guilt in adults with no history of psychological or autonomic disorder. Healthy adults completed a novel task, including an initial questionnaire about their habits and attitudes, followed by videos designed to elicit guilt, as well as the comparison emotions of amusement, disgust, sadness, pride, and neutral. During the video task, participants' swallowing rate, electrodermal activity, heart rate, respiration rate, and gastric activity rate were continuously recorded. Guilt was associated with alterations in gastric rhythms, electrodermal activity, and swallowing rate relative to some or all the comparison emotions. These findings suggest that there is a mixed pattern of sympathetic and parasympathetic activation during the experience of guilt. These results highlight potential therapeutic targets for modulation of guilt in neurologic and psychiatric disorders with deficient or elevated levels of guilt, such as frontotemporal dementia, posttraumatic stress disorder, and Obsessive-compulsive disorder.

Disentangling Reversal-learning Impairments in Frontotemporal Dementia and Alzheimer Disease.

BACKGROUND: Individuals with frontotemporal dementia (FTD) often present with poor decision-making, which can affect both their financial and social situations. Delineation of the specific cognitive impairments giving rise to impaired decision-making in individuals with FTD may inform treatment strategies, as different neurotransmitter systems have been associated with distinct patterns of altered decision-making. OBJECTIVE: To use a reversal-learning paradigm to identify the specific cognitive components of reversal learning that are most impaired in individuals with FTD and those with Alzheimer disease (AD) in order to inform future approaches to treatment for symptoms related to poor decision-making and behavioral inflexibility. METHOD: We gave 30 individuals with either the behavioral variant of FTD or AD and 18 healthy controls a stimulus-discrimination reversal-learning task to complete. We then compared performance in each phase between the groups. RESULTS: The FTD group demonstrated impairments in initial stimulus-association learning, though to a lesser degree than the AD group. The FTD group also performed poorly in classic reversal learning, with the greatest impairments being observed in individuals with frontal-predominant atrophy during trials requiring inhibition of a previously advantageous response. CONCLUSION: Taken together, these results and the reversal-learning paradigm used in this study may inform the development and screening of behavioral, neurostimulatory, or pharmacologic interventions aiming to address behavioral symptoms related to stimulus-reinforcement learning and response inhibition impairments in individuals with FTD.

Early symptoms in symptomatic and preclinical genetic frontotemporal lobar degeneration.

OBJECTIVES: The clinical heterogeneity of frontotemporal dementia (FTD) complicates identification of biomarkers for clinical trials that may be sensitive during the prediagnostic stage. It is not known whether cognitive or behavioural changes during the preclinical period are predictive of genetic status or conversion to clinical FTD. The first objective was to evaluate the most frequent initial symptoms in patients with genetic FTD. The second objective was to evaluate whether preclinical mutation carriers demonstrate unique FTD-related symptoms relative to familial mutation non-carriers. METHODS: The current study used data from the Genetic Frontotemporal Dementia Initiative multicentre cohort study collected between 2012 and 2018. Participants included symptomatic carriers (n=185) of a pathogenic mutation in chromosome 9 open reading frame 72 (C9orf72), progranulin (GRN) or microtubule-associated protein tau (MAPT) and their first-degree biological family members (n=588). Symptom endorsement was documented using informant and clinician-rated scales. RESULTS: The most frequently endorsed initial symptoms among symptomatic patients were apathy (23%), disinhibition (18%), memory impairments (12%), decreased fluency (8%) and impaired articulation (5%). Predominant first symptoms were usually discordant between family members. Relative to biologically related non-carriers, preclinical MAPT carriers endorsed worse mood and sleep symptoms, and C9orf72 carriers endorsed marginally greater abnormal behaviours. Preclinical GRN carriers endorsed less mood symptoms compared with non-carriers, and worse everyday skills. CONCLUSION: Preclinical mutation carriers exhibited neuropsychiatric symptoms compared with non-carriers that may be considered as future clinical trial outcomes. Given the heterogeneity in symptoms, the detection of clinical transition to symptomatic FTD may be best captured by composite indices integrating the most common initial symptoms for each genetic group.

Decoding auditory spatial and emotional information encoding using multivariate versus univariate techniques.

Emotion can have diverse effects on behaviour and perception, modulating function in some circumstances, and sometimes having little effect. Recently, it was identified that part of the heterogeneity of emotional effects could be due to a dissociable representation of emotion in dual pathway models of sensory processing. Our previous fMRI experiment using traditional univariate analyses showed that emotion modulated processing in the auditory 'what' but not 'where' processing pathway. The current study aims to further investigate this dissociation using a more recently emerging multi-voxel pattern analysis searchlight approach. While undergoing fMRI, participants localized sounds of varying emotional content. A searchlight multi-voxel pattern analysis was conducted to identify activity patterns predictive of sound location and/or emotion. Relative to the prior univariate analysis, MVPA indicated larger overlapping spatial and emotional representations of sound within early secondary regions associated with auditory localization. However, consistent with the univariate analysis, these two dimensions were increasingly segregated in late secondary and tertiary regions of the auditory processing streams. These results, while complimentary to our original univariate analyses, highlight the utility of multiple analytic approaches for neuroimaging, particularly for neural processes with known representations dependent on population coding.

Emotion and personal space: Neural correlates of approach-avoidance tendencies to different facial expressions as a function of coldhearted psychopathic traits.

In social interactions, humans are expected to regulate interpersonal distance in response to the emotion displayed by others. Yet, the neural mechanisms implicated in approach-avoidance tendencies to distinct emotional expressions have not been fully described. Here, we investigated the neural systems implicated in regulating the distance to different emotions, and how they vary as a function of empathy. Twenty-three healthy participants assessed for psychopathic traits underwent fMRI scanning while they viewed approaching and withdrawing angry, fearful, happy, sad and neutral faces. Participants were also asked to set the distance to those faces on a computer screen, and to adjust the physical distance from the experimenter outside the scanner. Participants kept the greatest distances from angry faces, and shortest from happy expressions. This was accompanied by increased activation in the dorsomedial prefrontal and orbitofrontal cortices, inferior frontal gyrus, and temporoparietal junction for angry and happy expressions relative to the other emotions. Irrespective of emotion, longer distances were kept from approaching faces, which was associated with increased activation in the amygdala and insula, as well as parietal and prefrontal regions. Amygdala activation was positively correlated with greater preferred distances to angry, fearful and sad expressions. Moreover, participants scoring higher on coldhearted psychopathic traits (lower empathy) showed reduced amygdala activation to sad expressions. These findings elucidate the neural mechanisms underlying social approach-avoidance, and how they are related to variations in empathy. Hum Brain Mapp 38:1492-1506, 2017. © 2016 Wiley Periodicals, Inc.

Enhanced conscious processing and blindsight-like detection of fear-conditioned stimuli under continuous flash suppression.

Emotional information, and specifically fear-related stimuli, have been shown to be preferentially processed at a nonconscious level and gain privileged access to awareness. However, recent evidence has emerged suggesting these findings are explained by low-level visual features rather than emotional salience. In this study, we tested the hypothesis that emotional salience increases both blindsight (i.e., detection with reduced awareness) and awareness of visually suppressed stimuli. We used fear conditioning to manipulate the emotional significance of neutral expressions presented under Continuous Flash Suppression. Fifty-two healthy participants were presented with perithreshold neutral faces, previously paired with an electric shock (CS+) or not (CS-), and asked to localise the quadrant wherein faces were presented and rate their level of confidence in the response. Results showed fear conditioning strength (indexed by skin conductance response to CS+ versus CS-) was positively associated with both increased "blindsight" and awareness of conditioned stimuli. These findings suggest emotional significance alone, and not merely low-level visual differences, can enhance pre-conscious and conscious processing of visual stimuli.

Opposing effects of perceptual versus working memory load on emotional distraction.

Throughout our day-to-day activities, we are subjected to numerous stimuli that compete for our attention; consequently, we must prioritize stimuli for further processing and influence over behaviour. Previous research has demonstrated that the extent to which task-irrelevant distractors are processed is mediated by the nature of the cognitive task, and the level of processing load. Importantly though, the interaction between cognitive task, processing load, and emotional distractor processing remains unclear. This is a particularly important question given the unique ways that emotion interacts with attention, and the fact that some other forms of processing load have been shown to reduce emotional distractor encoding. In the present study, participants were presented with emotional distractors during a perceptual and working memory task, under varying levels of load. In Experiment 1, we showed that the impact of emotional distractors on behaviour was reduced under conditions of high relative to low perceptual load. However, in sharp contrast, high working memory load was associated with increased emotional distraction. Importantly, these results were replicated in Experiment 2. Overall, the impact of processing load on emotional distraction varies according to the cognitive function being performed. These results raise the intriguing possibility that working memory operations deplete some of the cognitive resources needed to control the impact of emotion on behaviour. The findings, therefore, may have important implications for clinical populations featuring cognitive dysfunction and emotional dysregulation.

A network of amygdala connections predict individual differences in trait anxiety.

In this study we demonstrate that the pattern of an amygdala-centric network contributes to individual differences in trait anxiety. Individual differences in trait anxiety were predicted using maximum likelihood estimates of amygdala structural connectivity to multiple brain targets derived from diffusion-tensor imaging (DTI) and probabilistic tractography on 72 participants. The prediction was performed using a stratified sixfold cross validation procedure using a regularized least square regression model. The analysis revealed a reliable network of regions predicting individual differences in trait anxiety. Higher trait anxiety was associated with stronger connections between the amygdala and dorsal anterior cingulate cortex, an area implicated in the generation of emotional reactions, and inferior temporal gyrus and paracentral lobule, areas associated with perceptual and sensory processing. In contrast, higher trait anxiety was associated with weaker connections between amygdala and regions implicated in extinction learning such as medial orbitofrontal cortex, and memory encoding and environmental context recognition, including posterior cingulate cortex and parahippocampal gyrus. Thus, trait anxiety is not only associated with reduced amygdala connectivity with prefrontal areas associated with emotion modulation, but also enhanced connectivity with sensory areas. This work provides novel anatomical insight into potential mechanisms behind information processing biases observed in disorders of emotion.

"Blindsight" and subjective awareness of fearful faces: Inversion reverses the deficits in fear perception associated with core psychopathic traits.

Though emotional faces preferentially reach awareness, the present study utilised both objective and subjective indices of awareness to determine whether they enhance subjective awareness and "blindsight". Under continuous flash suppression, participants localised a disgusted, fearful or neutral face (objective index), and rated their confidence (subjective index). Psychopathic traits were also measured to investigate their influence on emotion perception. As predicted, fear increased localisation accuracy, subjective awareness and "blindsight" of upright faces. Coldhearted traits were inversely related to subjective awareness, but not "blindsight", of upright fearful faces. In a follow-up experiment using inverted faces, increased localisation accuracy and awareness, but not "blindsight", were observed for fear. Surprisingly, awareness of inverted fearful faces was positively correlated with coldheartedness. These results suggest that emotion enhances both pre-conscious processing and the qualitative experience of awareness, but that pre-conscious and conscious processing of emotional faces rely on at least partially dissociable cognitive mechanisms.

Emotion modulates allocentric but not egocentric stimulus localization: implications for dual visual systems perspectives.

Considerable evidence suggests that emotional cues influence processing prioritization and neural representations of stimuli. Specifically, within the visual domain, emotion is known to impact ventral stream processes and ventral stream-mediated behaviours; it remains unclear, however, the extent to which emotion impacts dorsal stream processes. In the present study, participants localized a visual target stimulus embedded within a background array utilizing allocentric localization (requiring an object-centred representation of visual space to perform an action) and egocentric localization (requiring purely target-directed actions), which are thought to differentially rely on the ventral versus dorsal visual stream, respectively. Simultaneously, a task-irrelevant negative, positive or neutral sound was presented to produce an emotional context. In line with predictions, we found that during allocentric localization, response accuracy was enhanced in the context of negative compared to either neutral or positive sounds. In contrast, no significant effects of emotion were identified during egocentric localization. These results raise the possibility that negative emotional auditory contexts enhance ventral stream, but not dorsal stream, processing in the visual domain. Furthermore, this study highlights the complexity of emotion-cognition interactions, indicating how emotion can have a differential impact on almost identical overt behaviours that may be governed by distinct neurocognitive systems.

Simultaneous conditioning of valence and arousal.

Evaluative conditioning (EC) refers to the change in the valence of a conditioned stimulus (CS) due to its pairing with a positive or negative unconditioned stimulus (US). To the extent that core affect can be characterised by the two dimensions of valence and arousal, EC has important implications for the origin of affective responses. However, the distinction between valence and arousal is rarely considered in research on EC or conditioned responses more generally. Measuring the subjective feelings elicited by a CS, the results from two experiments showed that (1) repeated pairings of a CS with a positive or negative US of either high or low arousal led to corresponding changes in both CS valence and CS arousal, (2) changes in CS arousal, but not changes in CS valence, were significantly related to recollective memory for CS-US pairings, (3) subsequent presentations of the CS without the US reduced the conditioned valence of the CS, with conditioned arousal being less susceptible to extinction and (4) EC effects were stronger for high arousal than low arousal USs. The results indicate that the conditioning of affective responses can occur simultaneously along two independent dimensions, supporting evidence in related areas that calls for a consideration of both valence and arousal. Implications for research on EC and the acquisition of emotional dispositions are discussed.

Prefrontal cortex structural and developmental associations with callous-unemotional traits and aggression.

Youths with high levels of callous-unemotional (CU) traits and aggression are at an increased risk for developing antisocial behaviours into adulthood. In this population, neurostructural grey matter abnormalities have been observed in the prefrontal cortex. However, the directionality of these associations is inconsistent, prompting some to suggest they may vary across development. Although similar neurodevelopmental patterns have been observed for other disorders featuring emotional and behavioural dysregulation, few studies have tested this hypothesis for CU traits, and particularly not for aggression subtypes. The current study sought to examine grey matter correlates of CU traits and aggression (including its subtypes), and then determine whether these associations varied by age. Fifty-four youths (10-19 years old) who were characterized for CU traits and aggression underwent MRI. Grey matter volume and surface area within the anterior cingulate cortex was positively associated with CU traits. The correlation between CU traits and medial orbitofrontal cortex (mOFC) volume varied significantly as a function of age, as did the correlation between reactive aggression and mOFC surface area. These associations became more positive with age. There were no significant findings for proactive/total aggression. Results are interpreted considering the potential for delayed cortical maturation in youths with high CU traits/aggression.

The impact of acute violent videogame exposure on neurocognitive markers of empathic concern.

Research examining the purported association between violent gaming and aggression remains controversial due to concerns related to methodology, unclear neurocognitive mechanisms, and the failure to adequately consider the role of individual differences in susceptibility. To help address these concerns, we used fMRI and an emotional empathy task to examine whether acute and cumulative violent gaming exposure were associated with abnormalities in emotional empathy as a function of trait-empathy. Emotional empathy was targeted given its involvement in regulating not only aggression, but also other important social functions such as compassion and prosocial behaviour. We hypothesized that violent gaming exposure increases the risk of aberrant social behaviour by altering the aversive value of distress cues. Contrary to expectations, neither behavioural ratings nor empathy-related brain activity varied as a function of violent gaming exposure. Notably, however, activation patterns in somatosensory and motor cortices reflected an interaction between violent gaming exposure and trait empathy. Thus, our results are inconsistent with a straightforward relationship between violent gaming exposure and reduced empathy. Furthermore, they highlight the importance of considering both individual differences in susceptibility and other aspects of cognition related to social functioning to best inform public concern regarding safe gaming practices.

The nonverbal expression of guilt in healthy adults.

Guilt is a negative emotion elicited by realizing one has caused actual or perceived harm to another person. One of guilt's primary functions is to signal that one is aware of the harm that was caused and regrets it, an indication that the harm will not be repeated. Verbal expressions of guilt are often deemed insufficient by observers when not accompanied by nonverbal signals such as facial expression, gesture, posture, or gaze. Some research has investigated isolated nonverbal expressions in guilt, however none to date has explored multiple nonverbal channels simultaneously. This study explored facial expression, gesture, posture, and gaze during the real-time experience of guilt when response demands are minimal. Healthy adults completed a novel task involving watching videos designed to elicit guilt, as well as comparison emotions. During the video task, participants were continuously recorded to capture nonverbal behaviour, which was then analyzed via automated facial expression software. We found that while feeling guilt, individuals engaged less in several nonverbal behaviours than they did while experiencing the comparison emotions. This may reflect the highly social aspect of guilt, suggesting that an audience is required to prompt a guilt display, or may suggest that guilt does not have clear nonverbal correlates.

Emotion modulates activity in the 'what' but not 'where' auditory processing pathway.

Auditory cortices can be separated into dissociable processing pathways similar to those observed in the visual domain. Emotional stimuli elicit enhanced neural activation within sensory cortices when compared to neutral stimuli. This effect is particularly notable in the ventral visual stream. Little is known, however, about how emotion interacts with dorsal processing streams, and essentially nothing is known about the impact of emotion on auditory stimulus localization. In the current study, we used fMRI in concert with individualized auditory virtual environments to investigate the effect of emotion during an auditory stimulus localization task. Surprisingly, participants were significantly slower to localize emotional relative to neutral sounds. A separate localizer scan was performed to isolate neural regions sensitive to stimulus location independent of emotion. When applied to the main experimental task, a significant main effect of location, but not emotion, was found in this ROI. A whole-brain analysis of the data revealed that posterior-medial regions of auditory cortex were modulated by sound location; however, additional anterior-lateral areas of auditory cortex demonstrated enhanced neural activity to emotional compared to neutral stimuli. The latter region resembled areas described in dual pathway models of auditory processing as the 'what' processing stream, prompting a follow-up task to generate an identity-sensitive ROI (the 'what' pathway) independent of location and emotion. Within this region, significant main effects of location and emotion were identified, as well as a significant interaction. These results suggest that emotion modulates activity in the 'what,' but not the 'where,' auditory processing pathway.

Emotional distraction and facilitation across sense and time.

Emotional stimuli can disrupt or enhance task performance according to factors that are presently poorly understood. One potentially important determinant is the sensory modality involved. In unimodal visual paradigms (visual task-irrelevant stimuli during a visual task) emotional stimuli frequently produce distraction effects; however, the effects across modalities appear more complex and may also depend on factors related to stimulus timing. It is entirely unclear how task-irrelevant visual stimuli impact auditory task performance in cross-modal paradigms. This project explored task performance as a function of sensory modality, emotional valence, and stimulus timing. In Study 1, participants (N = 50) completed a visual stimulus detection task in the presence of task-irrelevant negative and neutral images and sounds. Accuracy was disrupted in the presence of visual but not auditory emotional stimuli, particularly when the target and task-irrelevant stimulus appeared simultaneously. In Study 2, participants (N = 38) completed an equivalent auditory stimulus detection task. In sharp contrast to the effects observed with visual targets, response times and accuracy were enhanced in the presence of auditory emotional stimuli at the first timepoint but disrupted at later timepoints. However, there was no effect of task-irrelevant visual stimuli on auditory task performance. These findings demonstrate the importance of both sensory modality and timing in determining how emotional stimuli affect task performance and lay the groundwork for future studies examining the interaction between emotional and attentional processes. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Masking our emotions: Emotion recognition and perceived intensity differ by race and use of medical masks.

Although medical masks have played a key role in decreasing the transmission of communicable disease, they simultaneously reduce the availability of nonverbal cues fundamental to social interaction. In the present study, we determined the collective impact of medical masks on emotional expression recognition and perceived intensity as a function of actor race. Participants completed an emotional expression recognition task involving stimuli with or without medical masks. Across six basic emotional facial expressions, medical masks were associated with significantly more emotional expression recognition errors. Overall, the effects associated with race varied depending on the emotion and appearance of masks. Whereas recognition accuracy was higher for White relative to Black actors for anger and sadness, the opposite pattern was observed for disgust. Medical mask-wearing exacerbated actor-race related recognition differences for anger and surprise, but attenuated these differences for fear. Emotional expression intensity ratings were significantly reduced for all emotions except fear, where masks were associated with increased perceived intensity. Masks further increased already higher intensity ratings for anger in Black versus White actors. In contrast, masks eliminated the tendency to give higher intensity ratings for Black versus White sad and happy facial expressions. Overall, our results suggest that the interaction between actor race and mask wearing status with respect to emotional expression judgements is complex, varying by emotion in both direction and degree. We consider the implications of these results particularly in the context of emotionally charged social contexts, such as in conflict, healthcare, and policing.

The effects of oxytocin on social cognition and behaviour in frontotemporal dementia.

Patients with behavioural variant frontotemporal dementia demonstrate abnormalities in behaviour and social cognition, including deficits in emotion recognition. Recent studies suggest that the neuropeptide oxytocin is an important mediator of social behaviour, enhancing prosocial behaviours and some aspects of emotion recognition across species. The objective of this study was to assess the effects of a single dose of intranasal oxytocin on neuropsychiatric behaviours and emotion processing in patients with behavioural variant frontotemporal dementia. In a double-blind, placebo-controlled, randomized cross-over design, 20 patients with behavioural variant frontotemporal dementia received one dose of 24 IU of intranasal oxytocin or placebo and then completed emotion recognition tasks known to be affected by frontotemporal dementia and by oxytocin. Caregivers completed validated behavioural ratings at 8 h and 1 week following drug administrations. A significant improvement in scores on the Neuropsychiatric Inventory was observed on the evening of oxytocin administration compared with placebo and compared with baseline ratings. Oxytocin was also associated with reduced recognition of angry facial expressions by patients with behavioural variant frontotemporal dementia. Together these findings suggest that oxytocin is a potentially promising, novel symptomatic treatment candidate for patients with behavioural variant frontotemporal dementia and that further study of this neuropeptide in frontotemporal dementia is warranted.

Dissociable effects of acute versus cumulative violent video game exposure on the action simulation circuit in university students.

There is an ongoing debate as to whether violent video game exposure (VGE) has a negative impact on social functioning. This debate continues in part because of methodological concerns and the paucity of identifiable neurocognitive mechanisms. Also, little attention has been given to how specific personality characteristics may influence susceptibility to the purported effects. Using a combined experimental and cross-sectional approach, we examined the impact of VGE on action simulation as a function of trait coldheartedness in a sample of university students. Healthy adults played a violent or nonviolent version of Grand Theft Auto V before completing an fMRI measure of action simulation circuit (ASC) activity. Simulation-related activity was not significantly different between groups; however, greater overall activation was observed in left inferior frontal gyrus for those in the violent condition. Contrary to predictions, no evidence was observed that trait coldheartedness significantly interacts with violent gaming to influence ASC activation. However, prior cumulative VGE was negatively correlated with simulation-related activity in a subsection of the ASC. This study highlights a potential dissociation between the effects of acute versus cumulative violent gaming and may challenge assumptions that the directionality of effects for cross-sectional associations always mirror those of acute exposure.