Implicit Processes Research Articles

Event-related potentials in studies of the implicit component of cognitive biases

The review analyzes neurophysiological correlates of the implicit component of cognitive bias in the processes of perception and decision-making. The review identifies the leading methodological pipeline for analysis of the implicit component of cognitive bias, and justifies its choice in terms of the objectives of this review. The method of recording event-related potentials (ERPs) was chosen as the main approach to determining neurophysiological indicators of implicit processes. The analysis of literature allowed us to identify ERP components reproduced in the works of different authors using different variants of experimental designs for studying implicit bias, which may indicate the presence of common neurophysiological mechanisms associated with implicit processes in cognitive bias. The possibility of using other approaches to the analysis of EEG data to obtain new information about the mechanisms of implicit components in cognitive bias is also discussed.

Numerical simulation of influence of jet flow parameters on cone-cylinder-flare configuration

Abstract Reaction control system technology is used to realize attitude control or trajectory change. The hot jet effect should be considered to get more accurate aerodynamic characteristics as the flight vehicle develops. The simulation for hot jet flow needs more calculation resources, so it is important to research the suitable similarity parameters of jet flow. Then, we can use cold jet flow to simulate hot jet flow. In this paper, the influence of jet flow parameters is numerically studied on cone-cylinder-flare configuration. The numerical simulation method for hot jet flow is established, containing finite volume method, multi-component three-dimensional Reynolds Navier-Stokes equation with source terms, multi-block patched grid technique, and fully implicit processing method. The numerical method is verified by using experimental reference results, and the grid independence is assured. The numerical results reveal that the cold jet flowfield under the same mass flow ratio is more similar to the hot jet flowfield than the cold jet flowfield under the total temperature of 293 K. The maximum amplification factor difference between cold and hot jet flow is reduced from 14.1% to 1.2%.

The Body Knows Better: Sensorimotor signals reveal the interplay between implicit and explicit Sense of Agency in the human mind

Sense of Agency (SoA) is the feeling of control over our actions. SoA has been suggested to arise from both implicit sensorimotor integration as well as higher-level decision processes. SoA is typically measured by collecting participants' subjective judgments, conflating both implicit and explicit processing. Consequently, the interplay between implicit sensorimotor processing and explicit agency judgments is not well understood. Here, we evaluated in one exploratory and one preregistered experiment (N = 60), using a machine learning approach, the relation between a well-known mechanism of implicit sensorimotor adaptation and explicit SoA judgments. Specifically, we examined whether subjective judgments of SoA and sensorimotor conflicts could be inferred from hand kinematics in a sensorimotor task using a virtual hand (VH). In both experiments participants performed a hand movement and viewed a virtual hand making a movement that could either be synchronous with their action or include a parametric temporal delay. After each movement, participants judged whether their actual movement was congruent with the movement they observed. Our results demonstrated that sensorimotor conflicts could be inferred from implicit motor kinematics on a trial by trial basis. Moreover, detection of sensorimotor conflicts from machine learning models of kinematic data provided more accurate classification of sensorimotor congruence than participants' explicit judgments. These results were replicated in a second, preregistered, experiment. These findings show evidence of diverging implicit and explicit processing for SoA and suggest that the brain holds high-quality information on sensorimotor conflicts that is not fully utilized in the inference of conscious agency.

Emotional contagion to vocal smile revealed by combined pupil reactivity and motor resonance

The interplay between the different components of emotional contagion (i.e. emotional state and facial motor resonance), both during implicit and explicit appraisal of emotion, remains controversial. The aims of this study were (i) to distinguish between these components thanks to vocal smile processing and (ii) to assess how they reflect implicit processes and/or an explicit appraisal loop. Emotional contagion to subtle vocal emotions was studied in 25 adults through motor resonance and Autonomic Nervous System (ANS) reactivity. Facial expressions (fEMG: facial electromyography) and pupil dilation were assessed during the processing and judgement of artificially emotionally modified sentences. fEMG revealed that Zygomaticus major was reactive to the perceived valence of sounds, whereas the activity of Corrugator supercilii reflected explicit judgement. Timing analysis of pupil dilation provided further insight into both the emotional state and the implicit and explicit processing of vocal emotion, showing earlier activity for emotional stimuli than for neutral stimuli, followed by valence-dependent variations and a late judgement-dependent increase in pupil diameter. This innovative combination of different electrophysiological measures shed new light on the debate between central and peripherical views within the framework of emotional contagion.

A Matter of Memory? Age-Invariant Relative Clause Disambiguation and Memory Interference in Older Adults.

Past research suggests that Working Memory plays a role in determining relative clause attachment bias. Disambiguation preferences may further depend on Processing Speed and explicit memory demands in linguistic tasks. Given that Working Memory and Processing Speed decline with age, older adults offer a way of investigating the factors underlying disambiguation preferences. Additionally, older adults might be subject to more severe similarity-based memory interference given their larger vocabularies and slower lexical access. Nevertheless, memory interference and sentence disambiguation have not been combined in studies on older adults before. We used a self-paced reading paradigm under memory load interference conditions. Older (n=30) and Younger (n=35) readers took part in the study online; reading times were recorded and measures of comprehension accuracy and load recall were collected. This setup allowed for the implicit measurement of attachment biases and memory interference effects interactively. Results show that similarity-based interference affected both age groups equally, but was more pronounced in NP2-biased structures, which took participants generally longer to read. Attachment preferences did not differ by group and were unaffected by Working Memory span. However, accuracy on recall prompts was predicted by Working Memory span in both groups. Findings of greater interference in syntactically dispreferred structures support unified processing models where parsing constraints naturally interact. The lack of age differences on our measures further aligns with research finding age-invariant implicit language processing.

Explicit and implicit locomotor learning in individuals with chronic hemiparetic stroke.

Motor learning involves both explicit and implicit processes that are fundamental for acquiring and adapting complex motor skills. However, stroke may damage the neural substrates underlying explicit and/or implicit learning, leading to deficits in overall motor performance. Although both learning processes are typically used in concert in daily life and rehabilitation, no gait studies have determined how these processes function together after stroke when tested during a task that elicits dissociable contributions from both. Here, we compared explicit and implicit locomotor learning in individuals with chronic stroke to age- and sex-matched neurologically intact controls. We assessed implicit learning using split-belt adaptation (where two treadmill belts move at different speeds). We assessed explicit learning (i.e., strategy-use) using visual feedback during split-belt walking to help individuals explicitly correct for step length errors created by the split-belts. After the first 40 strides of split-belt walking, we removed the visual feedback and instructed individuals to walk comfortably, a manipulation intended to minimize contributions from explicit learning. We used a multirate state-space model to characterize individual explicit and implicit process contributions to overall behavioral change. The computational and behavioral analyses revealed that, compared with controls, individuals with chronic stroke demonstrated deficits in both explicit and implicit contributions to locomotor learning, a result that runs counter to prior work testing each process individually during gait. Since poststroke locomotor rehabilitation involves interventions that rely on both explicit and implicit motor learning, future work should determine how locomotor rehabilitation interventions can be structured to optimize overall motor learning. NEW & NOTEWORTHY Motor learning involves both implicit and explicit processes, the underlying neural substrates of which could be damaged after stroke. Although both learning processes are typically used in concert in daily life and rehabilitation, no gait studies have determined how these processes function together after stroke. Using a locomotor task that elicits dissociable contributions from both processes and computational modeling, we found evidence that chronic stroke causes deficits in both explicit and implicit locomotor learning.

Correlates of implicit semantic processing as revealed by representational similarity analysis applied to EEG

Correlates of implicit semantic processing as revealed by representational similarity analysis applied to EEG

Decomposing decision-making in preschoolers: Making decisions under ambiguity versus risk.

Decision-making in the real world involves multiple abilities. The main goal of the current study was to examine the abilities underlying the Preschool Gambling task (PGT), a preschool variant of the Iowa Gambling task (IGT), in the context of an integrative decision-making framework. Preschoolers (n = 144) were given the PGT along with four novel decision-making tasks assessing either decision-making under ambiguity or decision-making under risk. Results indicated that the ability to learn from feedback, to maintain a stable preference, and to integrate losses and gains contributed to the variance in decision-making on the PGT. Furthermore, children's awareness level on the PGT contributed additional variance, suggesting both implicit and explicit processes are involved. The results partially support the integrative decision-making framework and suggest that multiple abilities contribute to individual differences in decision-making on the PGT.

Sparse representation of neurons for encoding complex sounds in the auditory cortex

Listening in complex sound environments requires rapid segregation of different sound sources, e.g., having a conversation with multiple speakers or other environmental sounds. Efficient processing requires fast encoding of inputs to adapt to target sounds and identify relevant information from past experiences. This adaptation process represents an early phase of implicit learning of the sound statistics to form auditory memory. The auditory cortex (ACtx) plays a crucial role in this implicit learning process, but the underlying circuits are unknown. In awake mice, we recorded neuronal responses in different ACtx subfields using in vivo 2-photon imaging of excitatory and inhibitory (parvalbumin; PV) neurons. We used a paradigm adapted from human studies that induced rapid implicit learning from passively presented complex sounds and imaged A1 Layer 4 (L4), A1 L2/3, and A2 L2/3. In this paradigm, a frozen spectro-temporally complex ‘Target’ sound randomly re-occurred within a stream of other random complex sounds. All ACtx subregions contained distinct groups of cells specifically responsive to complex acoustic sequences, indicating that even thalamocortical input layers (A1 L4) respond to complex sounds. Subgroups of excitatory and inhibitory cells in all subfields showed decreased responses for re-occurring Target sounds, indicating that ACtx is highly involved in the early implicit learning phase. At the population level, activity was more decorrelated to Target sounds independent of the duration of frozen token, subregions, and cell type. These findings suggest that ACtx and its input layers contribute to the early phase of auditory memory for complex sounds, suggesting a parallel strategy across ACtx areas and between excitatory and inhibitory neurons.

Cognitive behavioral phenotyping of DSCAM heterozygosity as a model for autism spectrum disorder.

It is estimated that 1 in 36 children are affected by autism spectrum disorder (ASD) in the United States, which is nearly a twofold increase from a decade ago. Recent genetic studies have identified de novo loss-of-function (dnLoF) mutations in the Down Syndrome Cell Adhesion Molecule (DSCAM) as a strong risk factor for ASD. Previous research has shown that DSCAM ablation confers social interaction deficits and perseverative behaviors in mouse models. However, it remains unknown to what extent DSCAM underexpression captures the full range of behaviors, specifically cognitive phenotypes, presented in ASD. Here, we conducted a comprehensive cognitive behavioral phenotyping which revealed that loss of one copy of DSCAM, as in the DSCAM2J+/-, that is, DSCAM heterozygous mice, displayed hyperactivity, increased anxiety-like behavior, and motor coordination deficits. Additionally, hippocampal-dependent learning and memory was affected, including impairments in working memory, long-term memory, and contextual fear learning. Interestingly, implicit learning processes remained intact. Therefore, DSCAM LoF produces autistic-like behaviors that are similar to those observed in human cases of ASD. These findings further support a role for DSCAM dnLoF mutations in ASD and suggest DSCAM2J+/- as a suitable model for ASD research.

Oxytocin modulation of explicit pandemic stigma in men with varying social anxiety levels

ObjectiveStigma can create divisions within societies, hindering social cohesion and cooperation. Notably, it has significant public health implications, especially during infectious disease outbreaks like COVID-19. However, little is known about the neural and molecular basis of disease-related stigma and their association with individual differences. MethodsTo address this gap, we performed a double-blind, placebo-controlled, within-subject design study with 70 males, to investigate the effect of intranasal oxytocin (OT) administration on the explicit and implicit processing of disease-related stigma (i.e., COVID-19 stigma). After self-administrated 24 IU of OT or placebo, participants completed a stigma evaluation task and an Implicit Association Test (IAT) to assess the explicit and implicit processes of stigma evaluation, respectively. ResultsThe results showed that oxytocin amplified the differences between participants with high and low social anxiety in explicit COVID-19 stigma, with a higher inclination to attribute the stigmatized status of the stigmatized targets (i.e., COVID-19 related group) to personal causes in high social anxiety individuals, but reduced blame towards the stigmatized targets in low social anxiety individuals under oxytocin compared to placebo treatment. Furthermore, oxytocin strengthened the connections between responsibility attribution and the other processes (i.e., emotional, approach motivation, social deviance). While no modulation of oxytocin on implicit stigma emerged, oxytocin did modulate the associations between specific dimensions of explicit stigma (i.e., social deviance and approach motivation) and implicit stigma. ConclusionIn conclusion, these findings demonstrated that intranasal oxytocin administration could temporally impact the explicit cognitive judgment in disease-related stigma but not the implicit aspect; furthermore, it modulated in distinct ways in individuals with different levels of social anxiety. These findings highlight the trait-dependent oxytocin modulation on disease-related stigma, implying that oxytocin is partly involved in the endocrine system of disease-related stigma. By unraveling the molecular basis of stigma and its association with individual traits, such as social anxiety, we can tailor interventions to meet specific needs of different individuals in the future.

A graphical model to make explicit pharmacist clinical reasoning during medication review

Pharmacists’ roles have evolved substantially from traditional drug compounding and dispensing to encompass patient-centred clinical services. Pharmacist clinical reasoning, though fundamental to these new roles, generally remains implicit and understudied, particularly compared with that of other healthcare professionals, such as physicians. However, teaching and supervising the clinical services provided by pharmacists require a thorough understanding of the reasoning process involved. Several models describing pharmacist clinical reasoning have been developed, but they lack unified mapping.Here, we used an instrumental case study approach to develop a model of pharmacist clinical reasoning during medication review. Our model is adapted from a previously published modelling-using-typified-objects model of physician clinical reasoning in all its cognitive complexity. Our pharmacist model, validated after iterative development and expert consultation, aligns components of pharmacist clinical reasoning with those of physician clinical reasoning. The clinical case contains drug-related problems of variable clinical relevance, as well as numerous key elements (e.g., laboratory results, vital signs) necessary for conducting a medication review. The case serves both as the foundation for model development and as an illustrative step-by-step example within this article.Our model delineates the subprocesses of pharmacist clinical reasoning during medication review, offering a flexible, multipath structure that underscores the dynamic, nonlinear nature of the reasoning. The model might be able to clarify implicit cognitive processes, thus furthering the overarching objective of promoting reflective skill development among learners rather than relying solely on tacit knowledge gained through practice experience.

Implicit processing of linear prediction residual for replay attack detection

Implicit processing of linear prediction residual for replay attack detection

Learning facial structural dependency in 3D aligned space for face alignment

Facial structure's statistical characteristics offer pivotal prior information in facial landmark prediction, forming inter-dependencies among different landmarks. Such inter-dependencies ensure that predictions adhere to the shape distribution typical of natural faces. In challenging scenarios like occlusions or extreme facial poses, this structure becomes indispensable, which can help to predict elusive landmarks based on more discernible ones. While current deep learning methods do capture these landmark dependencies, it's often an implicit process heavily reliant on vast training datasets. We contest that such implicit modeling approaches fail to manage more challenging situations. In this paper, we propose a new method that harnesses the facial structure and explicitly explores inter-dependencies among facial landmarks in an end-to-end fashion. We propose a Structural Dependency Learning Module (SDLM). It uses 3D face information to map facial features into a canonical UV space, in which the facial structure is explicitly 3D semantically aligned. Besides, to explore the global relationships between facial landmarks, we take advantage of the self-attention mechanism in the image and UV spaces. We name the proposed method Facial Structure-based Face Alignment (FSFA). FSFA reinforces the landmark structure, especially under challenging conditions. Extensive experiments demonstrate that FSFA achieves state-of-the-art performance on the WFLW, 300W, AFLW, and COFW68 datasets.

Exploring corpus-invariant emotional acoustic feature for cross-corpus speech emotion recognition

Unsupervised cross-corpus speech emotion recognition (SER) is the task where the labeled training (source) and unlabeled testing (target) speech come from different corpora. Subspace transfer learning is one of the mainstream technologies for tackling cross-corpus SER challenges, which is achieved by utilizing projection matrices to learn common corpus-invariant feature representations between the source and target corpus. However, these methods mainly focus on mapping modeling from the input low-level descriptor (LLD) feature space to the corpus-invariant emotional feature space, which is an implicit feature mapping process that lacks interpretability for the selected features. This omission leads to an inability to pinpoint which acoustic features possess corpus invariance. To bridge this gap, we first propose a new transfer subspace learning framework with feature selection capabilities, i.e., the Corpus-Invariant Emotional Acoustic Feature Seeker (CAFS). Specifically, the CAFS integrates two core terms into the transfer regression loss function: (1) the emotion preservation term: This term includes emotional regression and the l2,1 norm, which is mainly used to select features and ensure that these features are related to emotions. (2) the corpus invariance preservation term: This item is mainly used to measure the difference in feature distribution between the source and target corpora. Minimizing this term bridges the gap between the source and target domains, ensuring that the chosen acoustic features are corpus-invariant. Subsequently, we conducted extensive cross-corpus SER experiments to explore corpus-invariant emotional acoustic features under various commonly used acoustic feature sets (IS09 and eGeMAPS). Through statistical analysis of the acoustic features sought by the CAFS framework, some acoustic features (e.g., Mel-Frequency Cepstral Coefficients (MFCC) and Formant) reveal their corpus-invariant properties, which could provide insights for feature selection in cross-corpus SER. These findings also lay the groundwork for a solid theoretical and empirical foundation for future research and applications in cross-corpus SER.

Implicit audiomotor adaptation

Sensorimotor adaptation alters mappings between motor commands and their predicted outcomes. Such remapping has been extensively studied in the visual domain, but the degree to which it occurs in modalities other than vision remains less well understood. Here, we manipulated the modality of reach target presentation to compare sensorimotor adaptation in response to perturbations of visual and auditory feedback location. We compared the extent of adaptation to perturbed sensory feedback for visual and auditory sensory modalities, and the magnitude of reach-direction aftereffects when the perturbation was removed. To isolate the contribution of implicit sensorimotor recalibration to adaptation in reach direction, we held sensory prediction errors and task-performance errors constant via a task-irrelevant clamp of sensory feedback. Seventy-two participants performed one of three experiments in which target location information and endpoint reach direction feedback were presented by loudspeakers (n = 24), headphones (n = 24), or a visual display (n = 24). Presentation durations for target stimuli (500 ms) and (non-veridical) endpoint feedback of reach direction (100 ms) were matched for visual and auditory modalities. For all three groups, when endpoint feedback was perturbed, adaptation was evident: reach-directions increased significantly in the direction opposite the clamped feedback, and a significant aftereffect persisted after participants were instructed that the perturbation had been removed. This study provides new evidence that implicit sensorimotor adaptation occurs in response to perturbed auditory feedback of reach direction, suggesting that an implicit neural process to recalibrate sensory to motor maps in response to sensory prediction errors may be ubiquitous across sensory modalities.

Motivation toward physical activity in patients with chronic musculoskeletal disorders: a meta-analysis of the efficacy of behavioural interventions

Musculoskeletal disorders (MDs) represent a global health issue, which can lead to disability. Physical activity (PA) reduces pain and increases physical function among patients with MDs. To promote behavioural changes, it seems important to focus on modifiable factors, such as motivation. Thus, this review aims to assess effects of interventions targeting PA on motivation towards PA. Searches used terms referring to “physical activity”, “motivation” and “chronic musculoskeletal disorders” on the databases PubMed, PsychINFO, MEDLINE, EMBASE, PEDro and Web of Science. All types of intervention—including but not limited to RCTs—were eligible for inclusion. Risk of bias was assessed with the Quality Assessment Tool for Studies with Diverse Designs (QATSDD). Among 6 489 abstracts identified, there were 387 eligible studies and 19 were included, reporting in total 34 effect sizes. The meta-analysis concerned 1 869 patients and indicated a small effect of interventions on change in motivation towards PA (d = 0.34; 95% CI [0.15; 0.54]; p < .01; k = 33). Behavioural interventions positively impact PA motivation in patients with MDs. In the literature, most studies focused on intervention’s effect on fear of movement. Future research should assess other explicit motivational constructs, as well as implicit processes.

A theoretical model of emotional processing in visual artmaking and art therapy

Current theoretical models of emotional processing rely mainly on detecting emotional processing through verbal, conscious, and cognitive processes. However, artmaking can potentially reveal embodied and implicit processes that may otherwise remain hidden in verbal expression. This paper attempts to close the scholarly gap by introducing a novel art-based emotional processing model that integrates emotional processing and art therapy literature, incorporating emotional meaning-making, awareness, acceptance, and memory consolidation. The art-based EP model explains the processes through which art creation may benefit emotional processing. It also elucidates the ways in which art therapy can be used to enhance therapeutic outcomes.

Individual differences in working memory capacity and temporal preparation: A secondary reanalysis.

The ability to prepare and maintain an optimal level of preparedness for action, across some unknown duration, is critical for human behavior. Temporal preparation has historically been analyzed in the context of reaction time (RT) experiments where the interval varies between the start of the trial, or foreperiod (FP), and the required response. Two main findings have come out of such paradigms: the variable FP effect (longer RTs to shorter vs. longer FPs) and the sequential FP effect (longer RTs when shorter FPs follow longer FPs). Several theoretical views of these FP effects have been proposed with some suggesting a dissociation while others argue for an implicit process driven by memory traces. One possible method to test these views of FP effects is to examine how individual differences in working memory capacity (WMC) moderate such effects. To this end, I reanalyzed data from three studies in which participants completed measures of WMC and a simple RT task with a variable FP. Results suggest that individual differences in WMC were related to the magnitude of the variable FP and the sequential FP effect in two of three individual studies. A "mega-analysis" provided supportive evidence for a relationship between WMC and both forms of FP effects. The present combined experimental-individual differences study provides a novel approach to better understand how and why individuals vary in temporal preparation ability. Through leveraging several large-scale databases unseen in FP research, I provide a new way of understanding FP effects and response timing more generally.

The role of explicit knowledge in compensating for a visuo-proprioceptive cue conflict.

It is unclear how explicit knowledge of an externally imposed mismatch between visual and proprioceptive cues of hand position affects perceptual recalibration. The Bayesian causal inference framework might suggest such knowledge should abolish the visual and proprioceptive recalibration that occurs when individuals perceive these cues as coming from the same source (their hand), while the visuomotor adaptation literature suggests explicit knowledge of a cue conflict does not eliminate implicit compensatory processes. Here we compared visual and proprioceptive recalibration in three groups with varying levels of knowledge about the visuo-proprioceptive cue conflict. All participants estimated the position of visual, proprioceptive, or combined targets related to their left index fingertip, with a 70mm visuo-proprioceptive offset gradually imposed. Groups 1, 2, and 3 received no information, medium information, and high information, respectively, about the offset. Information was manipulated using instructional and visual cues. All groups performed the task similarly at baseline in terms of variance, weighting, and integration. Results suggest the three groups recalibrated vision and proprioception differently, but there was no difference in variance or weighting. Participants who received only instructional cues about the mismatch (Group 2) did not recalibrate less, on average, than participants provided no information about the mismatch (Group 1). However, participants provided instructional cues and extra visual cues of their hands during the perturbation (Group 3) demonstrated significantly less recalibration than other groups. These findings are consistent with the idea that instructional cues alone are insufficient to override participants' intrinsic belief in common cause and reduce recalibration.