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Recent predictive processing accounts of perception and action point towards a key challenge for the nervous system in dynamically optimizing the balance between incoming sensory information and existing expectations regarding the state of the environment. Here, we report differences in the influence of the preceding sensory context on motor function, varying with respect to both clinical and subclinical features of autism spectrum disorder (ASD). Reach-to-grasp movements were recorded subsequent to an inactive period in which illusory ownership of a prosthetic limb was induced. We analysed the sub-components of reach trajectories derived using a minimum-jerk fitting procedure. Non-clinical adults low in autistic features showed disrupted movement execution following the illusion compared to a control condition. By contrast, individuals higher in autistic features (both those with ASD and non-clinical individuals high in autistic traits) showed reduced sensitivity to the presence of the illusion in their reaching movements while still exhibiting the typical perceptual effects of the illusion. Clinical individuals were distinct from non-clinical individuals scoring high in autistic features, however, in the early stages of movement. These results suggest that the influence of high-level representations of the environment differs between individuals, contributing to clinical and subclinical differences in motor performance that manifest in a contextual manner. As high-level representations of context help to explain fluctuations in sensory input over relatively longer time scales, more circumscribed sensitivity to prior or contextual information in autistic sensory processing could contribute more generally to reduced social comprehension, sensory impairments and a stronger desire for predictability and routine. [ABSTRACT FROM AUTHOR]

Often, during daily experiences, hearing peers' actions can activate motor regions of the CNS. This activation is termed auditory-motor resonance (AMR) and is thought to represent an internal simulation of one's motor memories. Currently, AMR is demonstrated at the neuronal level in the Macaque and songbird, in conjunction with evidence on a systems level in humans. Here, we review evidence of AMR development from a motor control perspective. In the context of internal modelling, we consider data that demonstrates sensory-guided motor learning and action maintenance, particularly the notion of sensory comparison seen during songbird vocalisation. We suggest that these comparisons generate accurate sensory-to-motor inverse mappings. Furthermore, given reports of mapping decay after songbird learning, we highlight the proposal that the maintenance of these sensorimotor maps potentially explains why frontoparietal regions are activated upon hearing known sounds (i.e., AMR). In addition, we also recommend that activation of these types of internal models outside of action execution may provide an ecological advantage when encountering known stimuli in ambiguous conditions. [ABSTRACT FROM AUTHOR]

Background Manipulation of multisensory integration induces illusory perceptions of body ownership. Patients with Parkinson's disease (PD), a neurodegenerative disorder characterised by striatal dopamine deficiency, are prone to illusions and hallucinations and have sensory deficits. Dopaminergic treatment also aggravates hallucinations in PD. Whether multisensory integration in body ownership is altered by PD is unexplored. Objective To study the effect of dopamine neurotransmission on illusory perceptions of body ownership. Methods We studied the Rubber Hand Illusion (RHI) in 21 PD patients (on- and off-medication) and 21 controls. In this experimental paradigm, synchronous stroking of a rubber hand and the subject's hidden real hand results in the illusory experience of ‘feeling’ the rubber hand, and proprioceptive mislocalisation of the real hand towards the rubber hand (‘proprioceptive drift’). Asynchronous stroking typically attenuates the RHI. Results The effect of PD on illusory experience depended on the stroking condition ( b = −2.15, 95% CI [−3.06, −1.25], p < .0001): patients scored questionnaire items eliciting the RHI experience higher than controls in the illusion-attenuating (asynchronous) condition, but not in the illusion-promoting (synchronous) condition. PD, independent of stroking condition, predicted greater proprioceptive drift ( b = 15.05, 95% CI [6.05, 24.05], p = .0022); the longer the disease duration, the greater the proprioceptive drift. However, the RHI did not affect subsequent reaching actions. On-medication patients scored both illusion (critical) and mock (control) questionnaire items higher than when off-medication, an effect that increased with disease severity (log ( OR ) =.014, 95% CI [.01, .02], p < .0001). Conclusion PD affects illusory perceptions of body ownership in situations that do not typically induce them, implicating dopamine deficit and consequent alterations in cortico-basal ganglia-thalamic circuitry in multisensory integration. Dopaminergic treatment appears to increase suggestibility generally rather than having a specific effect on own-body illusions, a novel finding with clinical and research implications. [ABSTRACT FROM AUTHOR]

The mental states of other people are components of the external world that modulate the activity of our sensory epithelia. Recent probabilistic frameworks that cast perception as unconscious inference on the external causes of sensory input can thus be expanded to enfold the brain’s representation of others’ mental states. This paper examines this subject in the context of the debate concerning the extent to which we have perceptual awareness of other minds. In particular, we suggest that the notion of perceptual presence helps to refine this debate: are others’ mental states experienced as veridical qualities of the perceptual world around us? This experiential aspect of social cognition may be central to conditions such as autism spectrum disorder, where representations of others’ mental states seem to be selectively compromised. Importantly, recent work ties perceptual presence to the counterfactual predictions of hierarchical generative models that are suggested to perform unconscious inference in the brain. This enables a characterisation of mental state representations in terms of their associated counterfactual predictions, allowing a distinction between spontaneous and explicit forms of mentalising within the framework of predictive processing. This leads to a hypothesis that social cognition in autism spectrum disorder is characterised by a diminished set of counterfactual predictions and the reduced perceptual presence of others’ mental states. [ABSTRACT FROM AUTHOR]

A disproportionate amount of research on impulsivity has focused on trait-related aspects rather than state fluctuations. As a result, the relationship between state impulsivity and moment-to-moment behaviour is unclear. Impulsivity is assumed to negatively affect self-control, but an alternative explanation, yet to be tested, could be that changes in state impulsivity and its homeostatic drivers influence the intensity of urges. We tested whether state impulsivity and hunger affected behaviour through a dual-process model, affecting both the experience of various urges, and self-control, using a smartphone-based experience sampling approach. We found that state impulsivity is associated with stronger urges, but we found no evidence of an association with diminished self-control. Being hungry amplifies urges across different types of urges, and both hunger and late hours are negatively related to the likelihood of controlling urges. These findings imply that the influence of hunger is not limited to the food domain, and provide new insight into the role of state impulsivity in daily life. [ABSTRACT FROM AUTHOR]

The question how the brain distinguishes between information about self and others is of fundamental interest to both philosophy and neuroscience. In this functional magnetic resonance imaging (fMRI) study, we sought to distinguish the neural substrates of representing a full‐body movement as one's movement and as someone else's movement. Participants performed a delayed match‐to‐sample working memory task where a retained full‐body movement (displayed using point‐light walkers) was arbitrarily labeled as one's own movement or as performed by someone else. By using arbitrary associations we aimed to address a limitation of previous studies, namely that our own movements are more familiar to us than movements of other people. A searchlight multivariate decoding analysis was used to test where information about types of movement and about self‐association was coded. Movement specific activation patterns were found in a network of regions also involved in perceptual processing of movement stimuli, however not in early sensory regions. Information about whether a memorized movement was associated with the self or with another person was found to be coded by activity in the left middle frontal gyrus (MFG), left inferior frontal gyrus (IFG), bilateral supplementary motor area, and (at reduced threshold) in the left temporoparietal junction (TPJ). These areas are frequently reported as involved in action understanding (IFG, MFG) and domain‐general self/other distinction (TPJ). Finally, in univariate analysis we found that selecting a self‐associated movement for retention was related to increased activity in the ventral medial prefrontal cortex. [ABSTRACT FROM AUTHOR]

Little is known about how different government communication strategies may systematically affect people's attitudes to staying home or going out during the COVID‐19 pandemic, nor how people perceive and process the risk of viral transmission in different scenarios. In this study, we report results from two experiments that examine the degree to which people's attitudes regarding the permissibility of leaving one's home are (1) sensitive to different levels of risk of viral transmission in specific scenarios, (2) sensitive to communication framings that are either imperative or that emphasize personal responsibility, or (3) creating 'loopholes' for themselves, enabling a more permissive approach to their own compliance. We find that the level of risk influences attitudes to going out, and that participants report less permissive attitudes to going out when prompted with messages framed in imperative terms, rather than messages emphasizing personal responsibility; for self‐loopholes, we find no evidence that participants' attitudes towards going out in specific scenarios are more permissive for themselves than for others. However, participants report they are more rigorous in staying home than others, which may cause moral licensing. Additionally, we find that age is negatively associated with permissive attitudes, and that male participants are more permissive to going out. Thus, during phases where it is important to promote staying home for all scenarios, including those perceived to be low‐risk, imperative communication may be best suited to increase compliance. [ABSTRACT FROM AUTHOR]

Depersonalisation is a common dissociative experience characterised by distressing feelings of being detached or 'estranged' from one's self and body and/or the world. The COVID-19 pandemic forcing millions of people to socially distance themselves from others and to change their lifestyle habits. We have conducted an online study of 622 participants worldwide to investigate the relationship between digital media-based activities, distal social interactions and peoples' sense of self during the lockdown as contrasted with before the pandemic. We found that increased use of digital media-based activities and online social e-meetings correlated with higher feelings of depersonalisation. We also found that the participants reporting higher experiences of depersonalisation, also reported enhanced vividness of negative emotions (as opposed to positive emotions). Finally, participants who reported that lockdown influenced their life to a greater extent had higher occurrences of depersonalisation experiences. Our findings may help to address key questions regarding well-being during a lockdown, in the general population. Our study points to potential risks related to overly sedentary, and hyper-digitalised lifestyle habits that may induce feelings of living in one's 'head' (mind), disconnected from one's body, self and the world. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated that individuals with methamphetamine dependence have impaired emotion recognition. However, heterogeneity in results from these studies may indicate that individual factors such as personality beliefs moderate emotion recognition deficits. Thus, we aimed to examine the relationship between dimensional estimates of dysfunctional personality beliefs and facial emotion recognition in 86 Australian treatment seekers with methamphetamine dependence. Dysfunctional beliefs were measured using the Personality Beliefs Questionnaire, and emotion recognition was measured with the Ekman's Faces Test. We applied hierarchical regression analyses to test the relationship between beliefs and emotion recognition after accounting for the effects of intelligence. Results indicated that personality beliefs reflecting antisocial and paranoid schemas together accounted for a significant increase in the variance in fear recognition (higher levels of beliefs associated with poorer fear recognition). Further, high levels of passive-aggressive personality beliefs were associated with a tendency to misclassify faces as disgust. Our findings suggest that antisocial, paranoid, and passive-aggressive dysfunctional personality beliefs may underlie inter-individual differences in emotion recognition in methamphetamine dependent individuals. Additional research is required to better understand the relationship between personality and social processing biases, and investigate the direct impact these have on the significant psychosocial impairments present in individuals with methamphetamine dependence. [ABSTRACT FROM AUTHOR]

The purpose of this review was to integrate leading paradigms in psychology and neuroscience with a theory of the embodied, situated human brain, called the Hierarchically Mechanistic Mind (HMM). The HMM describes the brain as a complex adaptive system that functions to minimize the entropy of our sensory and physical states via action-perception cycles generated by hierarchical neural dynamics. First, we review the extant literature on the hierarchical structure of the brain. Next, we derive the HMM from a broader evolutionary systems theory that explains neural structure and function in terms of dynamic interactions across four nested levels of biological causation (i.e., adaptation, phylogeny, ontogeny, and mechanism). We then describe how the HMM aligns with a global brain theory in neuroscience called the free-energy principle, leveraging this theory to mathematically formulate neural dynamics across hierarchical spatiotemporal scales. We conclude by exploring the implications of the HMM for psychological inquiry. [ABSTRACT FROM AUTHOR]

The efference copy account of the tickle effect (i.e., our inability to tickle ourselves) predicts no tickle effect (i.e., an ability to tickle ourselves) when the trajectory of a tactile stimulus is perturbed relative to the associated movement, and there is evidence in support of this. The active inference account, however, predicts the tickle effect should survive trajectory perturbation. We test these accounts of the tickle effect under the hypothesis that previous findings are due to attentional modulation, and that the tickle effect will be found in a paradigm with no conscious attention directed to the trajectory perturbation. We thus expected to find support for active inference. Our first experiment confirms this hypothesis, while our second seeks to explain previous findings in terms of the modulation of the tickle sensation when there is awareness of, and different degrees of attention to, the spatial tactile and kinesthetic trajectories. [ABSTRACT FROM AUTHOR]

Among all their sensations, agents need to distinguish between those caused by themselves and those caused by external causes. The ability to infer agency is particularly challenging under conditions of uncertainty. Within the predictive processing framework, this should happen through active control of prediction error that closes the action-perception loop. Here we use a novel, temporally-sensitive, behavioural proxy for prediction error to show that it is minimised most quickly when volatility is high and when participants report agency, regardless of the accuracy of the judgement. We demonstrate broad effects of uncertainty on accuracy of agency judgements, movement, policy selection, and hypothesis switching. Measuring autism traits, we find differences in policy selection, sensitivity to uncertainty and hypothesis switching despite no difference in overall accuracy. [ABSTRACT FROM AUTHOR]

Autism spectrum disorder (ASD) – and autistic traits more generally – are associated with a heterogeneous pattern of differences in cognitive function. These include differences in associative learning, attention, and processing of social information. All three cognitive functions have importance in clinical, educational, and research contexts. The present study investigates the relationships between these functions in the context of autistic traits in the neurotypical population. In an online study, we asked a group of over 400 people to complete the Autism Spectrum Quotient questionnaire. We also asked participants to complete one of two standard attentional learning paradigms – either a Kamin blocking or an attentional highlighting task. To investigate the relation of attention and learning to social information processing, we incorporated social cues in one of each kind of paradigm. We found Kamin blocking increased with increasing number of autistic traits, in particular the sub-trait attention switching, but only for non-social cues. We found that highlighting decreased with increasing number of traits, in particular the sub-trait communication, but only for social cues. We interpret these findings as evidence of a crucial role for attention in other characteristics of the broader autistic phenotype, and discuss the relevance of these results for cognitive explanations of autistic traits and symptoms. • We demonstrate links between autistic traits and cognitive processes related to attentional learning • We show Kamin blocking increases with autistic traits associated with attention • We show attentional highlighting decreases with autistic traits associated with communication, but only for social cues • We link individual differences in learning to differences in social cognition associated with autism [ABSTRACT FROM AUTHOR]

The optimism bias is a cognitive bias where individuals overestimate the likelihood of good outcomes and underestimate the likelihood of bad outcomes. Associated with improved quality of life, optimism bias is considered to be adaptive and is a promising avenue of research for mental health interventions in conditions where individuals lack optimism such as major depressive disorder. Here we lay the groundwork for future research on optimism as an intervention by introducing a domain general formal model of optimism bias, which can be applied in different task settings. Employing the active inference framework, we propose a model of the optimism bias as high precision likelihood biased towards positive outcomes. First, we simulate how optimism may be lost during development by exposure to negative events. We then ground our model in the empirical literature by showing how the developmentally acquired differences in optimism are expressed in a belief updating task typically used to assess optimism bias. Finally, we show how optimism affects action in a modified two-armed bandit task. Our model and the simulations it affords provide a computational basis for understanding how optimism bias may emerge, how it may be expressed in standard tasks used to assess optimism, and how it affects agents' decision-making and actions; in combination, this provides a basis for future research on optimism as a mental health intervention., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2025 The Author(s).)

Psilocybin has shown promise as a novel pharmacological intervention for treatment of depression, where post-acute effects of psilocybin treatment have been associated with increased positive mood and decreased pessimism. Although psilocybin is proving to be effective in clinical trials for treatment of psychiatric disorders, the information processing mechanisms affected by psilocybin are not well understood. Here, we fit active inference and reinforcement learning computational models to a novel two-armed bandit reversal learning task capable of capturing engagement behaviour in rats. The model revealed that after receiving psilocybin, rats achieve more rewards through increased task engagement, mediated by modification of forgetting rates and reduced loss aversion. These findings suggest that psilocybin may afford an optimism bias that arises through altered belief updating, with translational potential for clinical populations characterised by lack of optimism., (© 2024. The Author(s).)

Karl Friston's free-energy principle casts agents as self-evidencing through active inference. This implies that decision-making, planning and information-seeking are, in a generic sense, 'wishful'. We take an interdisciplinary perspective on this perplexing aspect of the free-energy principle and unpack the epistemological implications of wishful thinking under the free-energy principle. We use this epistemic framing to discuss the emergence of biases for self-evidencing agents. In particular, we argue that this elucidates an optimism bias as a foundational tenet of self-evidencing. We allude to a historical precursor to some of these themes, interestingly found in Machiavelli's oeuvre, to contextualise the universal optimism of the free-energy principle.

Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jakob Hohwy reports financial support was provided by Three Springs Foundation. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Adversarial collaboration has been championed as the gold standard for resolving scientific disputes but has gained relatively limited traction in neuroscience and allied fields. In this perspective, we argue that adversarial collaborative research has been stymied by an overly restrictive concern with the falsification of scientific theories. We advocate instead for a more expansive view that frames adversarial collaboration in terms of Bayesian belief updating, model comparison, and evidence accumulation. This framework broadens the scope of adversarial collaboration to accommodate a wide range of informative (but not necessarily definitive) studies while affording the requisite formal tools to guide experimental design and data analysis in the adversarial setting. We provide worked examples that demonstrate how these tools can be deployed to score theoretical models in terms of a common metric of evidence, thereby furnishing a means of tracking the amount of empirical support garnered by competing theories over time., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)

In Fenneman et al.'s (2022) review of theories and integrated impulsivity model, the authors distinguish between information impulsivity (i.e., acting without considering consequences) and temporal impulsivity (i.e., the tendency to pick sooner outcomes over later ones). The authors find that both types of impulsivity can be adaptive in different contexts. For example, when individuals experience scarcity of resources or when they are close to a minimum level of reserves (critical threshold). In this commentary, we extend their findings to a discussion about the measurement of impulsivity. We argue that a common method for measuring temporal impulsivity in which people make decisions between outcomes that are spaced out in time (intertemporal choice tasks), puts individuals in a specific context that is unlikely to generalize well to other situations. Furthermore, trait measures of impulsivity may only be modestly informative about future impulsive behavior because they largely abstract away from important context. To address these issues, we advocate for the development of dynamic measures of the two types of impulsivity. We argue that measuring temporal impulsivity in naturalistic contexts with varying environmental and state parameters could provide insights into whether individuals (i.e., humans and nonhuman animals) react to environmental changes adaptively, while trait measures of impulsivity more generally should collect and provide more contextual information. Dynamic measurement of different types of impulsivity will also allow for more discussion about adaptive impulsive responses in different contexts, which could help combat the stigmatization of various disorders associated with impulsivity. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Background: People often feel urges to engage in activities that violate pandemic public health guidelines. Research on these urges has been reliant on measures of typical behaviour, which fail to capture these urges as they unfold. Guideline adherence could be improved through interventions, but few methods allow for ecologically valid observation of the range of behaviours that pandemic guidelines prescribe., Methods: In this preregistered parallel randomised trial, 95 participants aged 18-65 from the UK were assigned to three groups using blinded block randomisation, and engaged in episodic future thinking (n = 33), compassion exercises (n = 31), or a control procedure (n = 31). Following an ecological momentary assessment procedure, participants report on the intensity of their occurrent urges (min. 1, max. 10) and their ability to control them. The study further investigates whether, and through which mechanism, state impulsivity and vaccine attitudes affect guideline adherence., Results: Episodic future thinking (b = -1.80) and compassion exercises (b = -1.45) reduced the intensity of urges. State impulsivity is associated with stronger urges, but we found no evidence that vaccine hesitancy predicts lesser self-control., Conclusions: We conclude that episodic future thinking exercises and compassion training may be used to decrease non-compliance urges of individuals who are an acute public health risk for the community, such as those in voluntary isolation., (© 2023. The Author(s).)

Online speech processing imposes significant computational demands on the listening brain, the underlying mechanisms of which remain poorly understood. Here, we exploit the perceptual "pop-out" phenomenon (i.e. the dramatic improvement of speech intelligibility after receiving information about speech content) to investigate the neurophysiological effects of prior expectations on degraded speech comprehension. We recorded electroencephalography (EEG) and pupillometry from 21 adults while they rated the clarity of noise-vocoded and sine-wave synthesized sentences. Pop-out was reliably elicited following visual presentation of the corresponding written sentence, but not following incongruent or neutral text. Pop-out was associated with improved reconstruction of the acoustic stimulus envelope from low-frequency EEG activity, implying that improvements in perceptual clarity were mediated via top-down signals that enhanced the quality of cortical speech representations. Spectral analysis further revealed that pop-out was accompanied by a reduction in theta-band power, consistent with predictive coding accounts of acoustic filling-in and incremental sentence processing. Moreover, delta-band power, alpha-band power, and pupil diameter were all increased following the provision of any written sentence information, irrespective of content. Together, these findings reveal distinctive profiles of neurophysiological activity that differentiate the content-specific processes associated with degraded speech comprehension from the context-specific processes invoked under adverse listening conditions., (© The Author(s) 2022. Published by Oxford University Press.)

Background: How we build and maintain representations of ourselves involves both explicit features which are consciously accessible on reflection and implicit processes which are not, such as attentional biases. Understanding relations between different ways of measuring self-cognition both within and across such cognitive domains is important for understanding how selves may differ from one another, and whether self-cognition is best understood as largely uni-dimensional or more multi-dimensional. Further, uncovering this structure should inform research around how self-cognition relates to psychiatric and psychological conditions. This study explores the relations between different constructs of self-cognition and how variability within them relates to psychiatric traits., Methods: Our final dataset includes within-subject (n = 288, general population) measures of explicit self-concept (using both the Self Concept Clarity Scale and Self Concept and Identity Measure), implicit self-prioritisation in a shape-label matching task (for both reaction time and sensitivity) and measurement of traits for five psychiatric conditions (autism, borderline personality disorder, schizophrenia, depression and anxiety). We first test whether self-cognitive measures within and across domains are correlated within individuals. We then test whether these dimensions of self-cognition support a binary distinction between psychiatric conditions that either are or are not characterised in terms of self, or whether they support self-cognition as transdiagnostically predictive of the traits associated with psychiatric conditions. To do this we run a series of planned correlations, regressions, and direct correlation comparison statistics., Results: Results show that implicit self-prioritisation measures were not correlated with the explicit self-concept measures nor the psychiatric trait measures. In contrast, all the psychiatric traits scores were predicted, to varying degrees, by poorer explicit self-concept quality. Specifically, borderline personality disorder traits were significantly more strongly associated with composite explicit self-concept measures than any of depression, anxiety, or autism traits scores were., Conclusions: Our results suggest that selves can differ considerably, along different cognitive dimensions. Further, our results show that self-cognition may be a promising feature to include in future dimensional characterisations of psychiatric conditions, but care should be taken to choose relevant self-cognitive domains., (© 2022. The Author(s).)

Cory COVID-Bot is an artificial intelligence chatbot designed and built by a multisector collaboration to help people safely step towards COVID normal. Achieving COVID normal and avoiding unnecessary adverse health outcomes requires effective communication to the public regarding COVID safe behaviors, but reaching young, culturally and linguistically diverse members of the community is challenging for government. Cory COVID-Bot was developed to directly engage with difficult to reach populations in English and Vietnamese. In order to resolve public ambiguity and uncertainty about public health guidelines, and to stimulate safe behavior, Cory COVID-Bot provides updated recommendations and behavior change interventions, which emphasize the importance of COVID safe behaviors.

Functional motor disorders (FMDs) are distinguished by signs that lack congruence with recognised patterns of organic disease and show inconsistency over time. Their pathophysiology is poorly understood, but there is evidence that irregularities in perceptual and cognitive processing lie at the heart of these conditions. Here, we draw on a predictive coding account of functional neurological disorders to study perceptual decision-making in three groups: 20 patients with FMDs (14 with functional movements and 6 with functional weakness), 20 with phenotypically-matched organic motor disorders, and 20 age-matched healthy controls. We examine four cognitive domains with putative roles in FMD pathogenesis: attention, expectations, sensory processing (perceptual sensitivity), and metacognition (introspective evaluation of performance). We augmented a dual-task paradigm, manipulating the visual contrast required for target detection to examine these domains in one design. With sensory input (stimulus contrast) psychometrically adjusted to staircase target detection at a fixed level for all groups, the FMD group exhibited statistically equivalent attentional, expectational and metacognitive processing to healthy controls. However, we demonstrate Bayesian evidence and a frequentist trend that FMD patients require higher visual contrast than controls to maintain the same detection sensitivity (BF 10  = 8.1, p holm  = .066). This was statistically equivalent to the visual contrast required by the organic group, and unlikely to be accounted for by medication use or comorbid psychopathology. The organic group showed differences in processing of attention and expectations for target detection that were not observed in either healthy controls or the functional group. The distinctive behavioural profile of FMDs may arise from abnormalities in basic sensory processing, while higher attentional, expectational and metacognitive mechanisms remain intact. Conceptualising functional neurological disorders under a predictive coding account may consolidate and refine existing pathophysiological theories about them., Competing Interests: Declaration of Competing Interest We declare we have no competing interests., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Perception results from complex interactions among sensory and cognitive processes across hierarchical levels in the brain. Intermodulation (IM) components, used in frequency tagging neuroimaging designs, have emerged as a promising direct measure of such neural interactions. IMs have initially been used in electroencephalography (EEG) to investigate low-level visual processing. In a more recent trend, IMs in EEG and other neuroimaging methods are being used to shed light on mechanisms of mid- and high-level perceptual processes, including the involvement of cognitive functions such as attention and expectation. Here, we provide an account of various mechanisms that may give rise to IMs in neuroimaging data, and what these IMs may look like. We discuss methodologies that can be implemented for different uses of IMs and we demonstrate how IMs can provide insights into the existence, the degree and the type of neural integration mechanisms at hand. We then review a range of recent studies exploiting IMs in visual perception research, placing an emphasis on high-level vision and the influence of awareness and cognition on visual processing. We conclude by suggesting future directions that can enhance the benefits of IM-methodology in perception research., (Copyright © 2019 Elsevier Inc. All rights reserved.)