Subliminal Priming-State of the Art and Future Perspectives

Sex Differences in Sexual Motivation in Humans and Other Mammals: The Role of Conscious and Unconscious Processes

In self-report questionnaires, men report higher scores than women on variables such as desire for sex, frequency of sexual thoughts, number of sex partners, etc. Based on this, men are considered to have a higher level of sexual motivation than women. However, retrospective self-reports may be unsuitable for estimations of the inherent level of sexual motivation. We review data on automatic (unconsciously controlled) responses and measures of implicit motivation during exposure to sexual stimuli. These responses and measures are inaccessible to willful manipulations and make it possible to determine whether the sex difference in answers to questionnaires is replicated when volitional response manipulations are unlikely. We complement the human data with observations from some rodent and non-human primate species. The attentional resources allotted to stimuli with sexual relevance as well as genital responses to such stimuli are similar in men and women. Measures of implicit motivation also fail to detect any sex difference. Finally, the frequency of masturbation is superior in female infants before the age at which social expectations begin to determine behavior. Neither in rodents nor in non-human primates is there any clear-cut evidence for sex differences in motivation. It seems that males and females are similar with regard to the intensity of sexual motivation. The responses to questionnaires may be affected by social learning of sexual scripts and/or the inferior quality of sexual experiences in women, among other things.

Action-outcome delays modulate the temporal expansion of intended outcomes

The phenomenon of intentional binding pertains to the perceived connection between a voluntary action and its anticipated result. When an individual intends an outcome, it appears to subjectively extend in time due to a pre-activation of the intended result, particularly evident at shorter action-outcome delays. However, there is a concern that the operationalisation of intention might have led to a mixed interpretation of the outcome expansion attributed to the pre-activation of intention, given the sensitivity of time perception and intentional binding to external cues that could accelerate the realisation of expectations. To investigate the expansion dynamics of an intended outcome, we employed a modified version of the temporal bisection task in two experiments. Experiment 1 considered the action-outcome delay as a within-subject factor, while experiment 2 treated it as a between-subject factor. The results revealed that the temporal expansion of an intended outcome was only evident under the longer action-outcome delay condition. We attribute this observation to working memory demands and attentional allocation due to temporal relevancy and not due to pre-activation. The discrepancy in effects across studies is explained by operationalising different components of the intentional binding effect, guided by the cue integration theory. Moreover, we discussed speculative ideas regarding the involvement of specific intentions based on the proximal intent distal intent (PIDI) theory and whether causality plays a role in temporal binding. Our study contributes to the understanding of how intention influences time perception and sheds light on how various methodological factors, cues, and delays can impact the dynamics of temporal expansion associated with an intended outcome.

Anxiety and Avoidance in Close Relationships Are Associated With Responses to Negative and Positive Stimuli

Humans tend to assign valence to objects, people, and events in the environment, but there are individual differences in the evaluation of the affective nature of these environmental stimuli. This exploratory study investigated how individual differences in anxiety and avoidance in close relationships are associated with the emotional appraisal of valenced and neutral stimuli. Participants evaluated negative, neutral, and positive stimuli for emotional valence in an image classification task. There was a positivity offset across all participants, in that neutral stimuli were evaluated as more positive than negative. Individuals higher on the Experiences in Close Relationships-Anxiety subscale showed a negativity bias in reaction times and ratings: they had faster response times to negative than to positive stimuli and had a greater tendency to evaluate positive stimuli as "negative." Individuals higher on the Experiences in Close Relationships-Avoidance subscale gave more positive ratings of negative stimuli and more negative ratings of positive stimuli, which may suggest a general blunted response to emotional stimuli. Findings are discussed in the context of the literature on individual differences and emotional appraisal of stimuli.

Disentangling affect from self-esteem using subliminal conditioning

Across three experiments, participants underwent conditioning sequences where the self-referential term I AM (Conditioned Stimulus, or CS+) or a scrambled counterpart M IA (CS-) was paired with either neutral (Unconditioned Stimulus, or US-) or positive attributes (US+). CS and US were presented under subliminal and/or visible conditions. A normalized indicator of affective shift and an explicit self-esteem measure were deployed as outcome measures. In Experiment 1 (N = 60), subliminal CS+ followed by visible US+ produced a significant affective shift only. Experiment 2 (N = 59) presented CS and US under subliminal conditions, which did not influence either outcome measure. In Experiment 3 (N = 60), visible CS appeared with visible US, which resulted in a significant effect on explicit self-esteem only. These findings highlight the central roles of CS and/or US visibility towards influencing reported affect and self-esteem. We theorize that configural components of subliminally presented stimuli can become perceptually encoded and influence self-related affect non-consciously.

The Architecture of Object-Based Attention

The allocation of attention to objects raises several intriguing questions: What are objects, how does attention access them, what anatomical regions are involved? Here, we review recent progress in the field to determine the mechanisms underlying object-based attention. First, findings from unconscious priming and cueing suggest that the preattentive targets of object-based attention can be fully developed object representations that have reached the level of identity. Next, the control of object-based attention appears to come from ventral visual areas specialized in object analysis that project downward to early visual areas. How feedback from object areas can accurately target the object's specific locations and features is unknown but recent work in autoencoding has made this plausible. Finally, we suggest that the three classic modes of attention may not be as independent as is commonly considered, and instead could all rely on object-based attention. Specifically, studies show that attention can be allocated to the separated members of a group-without affecting the space between them-matching the defining property of feature-based attention. At the same time, object-based attention directed to a single small item has the properties of space-based attention. We outline the architecture of object-based attention, the novel predictions it brings, and discuss how it works in parallel with other attention pathways.

Implicit bias training can remove bias from subliminal stimuli, restoring choice divergence: A proof-of-concept study

Subliminal information can influence our conscious life. Subliminal stimuli can influence cognitive tasks, while endogenous subliminal neural information can sway decisions before volition. Are decisions inextricably biased towards subliminal information? Or can they diverge away from subliminal biases via training? We report that implicit bias training can remove biases from subliminal sensory primes. We first show that subliminal stimuli biased an imagery-content decision task. Participants (n = 17) had to choose one of two different patterns to subsequently imagine. Subliminal primes significantly biased decisions towards imagining the primed option. Then, we trained participants (n = 7) to choose the non-primed option, via post choice feedback. This training was successful despite participants being unaware of the purpose or structure of the reward schedule. This implicit bias training persisted up to one week later. Our proof-of-concept study indicates that decisions might not always have to be biased towards non-conscious information, but instead can diverge from subliminal primes through training.

Exploring the role of empathy in prolonged grief reactions to bereavement

Grief reactions to the bereavement of a close individual could involve empathy for pain, which is fundamental to social interaction. To explore whether grief symptoms interact with social relatedness to a person to whom one directs empathy to modulate the expression of empathy, we administered an empathy task to 28 bereaved adults during functional magnetic resonance imaging, in which participants were subliminally primed with facial stimuli (e.g., faces of their deceased or living relative, or a stranger), each immediately followed by a visual pain stimulus. Individuals' grief severity promoted empathy for the pain stimulus primed with the deceased's face, while it diminished the neural response to the pain stimulus primed with the face of either their living relative or a stranger in the medial frontal cortex (e.g., the right dorsal anterior cingulate cortex). Moreover, preliminary analyses showed that while the behavioral empathic response was promoted by the component of "longing" in the deceased priming condition, the neural empathic response was diminished by the component of "avoidance" in the stranger priming condition. Our results suggest an association between grief reactions to bereavement and empathy, in which grief symptoms interact with interpersonal factors to promote or diminish empathic responses to others' pain.

Temporal pain processing in the primary somatosensory cortex and anterior cingulate cortex

Pain is known to have sensory and affective components. The sensory pain component is encoded by neurons in the primary somatosensory cortex (S1), whereas the emotional or affective pain experience is in large part processed by neural activities in the anterior cingulate cortex (ACC). The timing of how a mechanical or thermal noxious stimulus triggers activation of peripheral pain fibers is well-known. However, the temporal processing of nociceptive inputs in the cortex remains little studied. Here, we took two approaches to examine how nociceptive inputs are processed by the S1 and ACC. We simultaneously recorded local field potentials in both regions, during the application of a brain-computer interface (BCI). First, we compared event related potentials in the S1 and ACC. Next, we used an algorithmic pain decoder enabled by machine-learning to detect the onset of pain which was used during the implementation of the BCI to automatically treat pain. We found that whereas mechanical pain triggered neural activity changes first in the S1, the S1 and ACC processed thermal pain with a reasonably similar time course. These results indicate that the temporal processing of nociceptive information in different regions of the cortex is likely important for the overall pain experience.

Expertise-dependent perceptual performance in chess tasks with varying complexity

Perceptual performance, anticipating opponents' strategies, and judging chess positions especially in subliminal processing is related to expertise level and dependent on chunking processes. It becomes obvious that chess expertise is a multidimensional phenomenon related predominantly to experience. Under consideration of chess expertise categorization, we conducted two priming experiments expanding existing designs by gradually increasing the target and task complexity. The main aim was the evaluation of potential visuocognitive limitations. The results reveal experts' perceptual superiority manifested by their faster reaction times in settings with increased stimulus and task complexity. Further, experts' priming effects seem to be affected by the target content and/ or priming duration. For short prime duration, experts show priming effects only for less complex prime-target content. Interestingly, for longer prime duration and more complex prime-target content, all participants reveal priming effects. In summary, we argue that experts' visuocognitive processing (i.e., detecting or anticipating potential threats to the king) is rooted in a more efficient visuocognition due to stored chunks of checking and mating constellations. We suggest that visuocognitive limitations are related also to the prime-target complexity as well as to the task. Further investigations must be conducted in order to elucidate the factors with an increased impact on chess players' performance.

Awareness and consciousness in humans and animals – neural and behavioral correlates in an evolutionary perspective

Awareness or consciousness in the context of stimulus perception can directly be assessed in well controlled test situations with humans via the persons’ reports about their subjective experiences with the stimuli. Since we have no direct access to subjective experiences in animals, their possible awareness or consciousness in stimulus perception tasks has often been inferred from behavior and cognitive abilities previously observed in aware and conscious humans. Here, we analyze published human data primarily on event-related potentials and brain-wave generation during perception and responding to sensory stimuli and extract neural markers (mainly latencies of evoked-potential peaks and of gamma-wave occurrence) indicating that a person became aware or conscious of the perceived stimulus. These neural correlates of consciousness were then applied to sets of corresponding data from various animals including several species of mammals, and one species each of birds, fish, cephalopods, and insects. We found that the neural markers from studies in humans could also successfully be applied to the mammal and bird data suggesting that species in these animal groups can become subjectively aware of and conscious about perceived stimuli. Fish, cephalopod and insect data remained inconclusive. In an evolutionary perspective we have to consider that both awareness of and consciousness about perceived stimuli appear as evolved, attention-dependent options added to the ongoing neural activities of stimulus processing and action generation. Since gamma-wave generation for functional coupling of brain areas in aware/conscious states is energetically highly cost-intensive, it remains to be shown which animal species under which conditions of lifestyle and ecological niche may achieve significant advantages in reproductive fitness by drawing upon these options. Hence, we started our discussion about awareness and consciousness in animals with the question in how far these expressions of brain activity are necessary attributes for perceiving stimuli and responding in an adaptive way.

Subliminal Priming Effects of Masked Social Hierarchies During a Categorization Task: An Event-Related Brain Potentials Study

Evidence so far shows that status detection increases attentional resources, especially for high hierarchies. However, little is known about the effects of masked social status cues on cognition. Here, we explore the masked priming effects of social status cues during a categorization task. For this purpose, we use Event-Related brain Potentials (ERP) time-locked to the presentation of two types of artworks (Christian, non-Christian) primed by masked social hierarchies sorted into two types (religious, military), and in two ranks (high, low) each. ERP results indicate early attention effects at N1, showing larger amplitudes for the processing of artworks after high and military ranks. Thereafter, the P3a increased for all artworks primed by religious vs. military figures, indicating a relevant role of task demands at this processing stage. Our results remark the automaticity of hierarchy detection and extend previous findings on the effects of social status cues on complex cognitive processes.

Organization and Priming of Long-term Memory Representations with Two-phase Plasticity

Background / Introduction

In recurrent neural networks in the brain, memories are represented by so-called Hebbian cell assemblies. Such assemblies are groups of neurons with particularly strong synaptic connections formed by synaptic plasticity and consolidated by synaptic tagging and capture (STC). To link these synaptic mechanisms to long-term memory on the level of cognition and behavior, their functional implications on the level of neural networks have to be understood.

Methods

We employ a biologically detailed recurrent network of spiking neurons featuring synaptic plasticity and STC to model the learning and consolidation of long-term memory representations. Using this, we investigate the effects of different organizational paradigms, and of priming stimulation, on the functionality of multiple memory representations. We quantify these effects by the spontaneous activation of memory representations driven by background noise.

Results

We find that the learning order of the memory representations significantly biases the likelihood of activation towards more recently learned representations, and that hub-like overlap structure counters this effect. We identify long-term depression as the mechanism underlying these findings. Finally, we demonstrate that STC has functional consequences for the interaction of long-term memory representations: 1. intermediate consolidation in between learning the individual representations strongly alters the previously described effects, and 2. STC enables the priming of a long-term memory representation on a timescale of minutes to hours.

Conclusion

Our findings show how synaptic and neuronal mechanisms can provide an explanatory basis for known cognitive effects.

Attention-Setting and Human Mental Function

This article provides an introduction to experimental research on top-down human attention in complex scenes, written for cognitive scientists in general. We emphasize the major effects of goals and intention on mental function, measured with behavioral experiments. We describe top-down attention as an open category of mental actions that initiates particular task sets, which are assembled from a wide range of mental processes. We call this attention-setting. Experiments on visual search, task switching, and temporal attention are described and extended to the important human time scale of seconds.

Cautionary Observations Concerning the Introduction of Psychophysiological Biomarkers into Neuropsychiatric Practice

The combination of statistical learning technologies with large databases of psychophysiological data has appropriately generated enthusiastic interest in future clinical applicability. It is argued here that this enthusiasm should be tempered with the understanding that significant obstacles must be overcome before the systematic introduction of psychophysiological measures into neuropsychiatric practice becomes possible. The objective of this study is to identify challenges to this effort. The nonspecificity of psychophysiological measures complicates their use in diagnosis. Low test-retest reliability complicates use in longitudinal assessment, and quantitative psychophysiological measures can normalize in response to placebo intervention. Ten cautionary observations are introduced and, in some instances, possible directions for remediation are suggested.

Identifying knowledge important to teach about the nervous system in the context of secondary biology and science education-A Delphi study

Teaching about the nervous system has become a challenging task in secondary biology and science education because of the fast development in the field of neuroscience. A major challenge is to determine what content to teach. Curricula goals are often too general to guide instruction, and information about the nervous system has become overwhelming and diverse with ubiquitous relevance in society. In addition, several misconceptions and myths are circulating in educational communities causing world-wide confusion as to what content is correct. To help teachers, textbook authors, and curricula developers in this challenging landscape of knowledge, the aim of the present study is to identify the expert view on what knowledge is important for understanding the nervous system in the context of secondary biology and science education. To accomplish this, we have conducted a thematic content analysis of textbooks followed by a Delphi study of 15 experts in diverse but relevant fields. The results demonstrate six curriculum themes including gross anatomy and function, cell types and functional units, the nerve signal, connections between neurons, when nerve signals travel through networks of neurons, and plasticity in the nervous system, as well as 26 content principles organized in a coherent curriculum progression from general content to more specific content. Whereas some of the principles clarify and elaborate on traditional school biology knowledge, others add new knowledge to the curriculum. Importantly, the new framework for teaching about the nervous system presented here, meets the needs of society, as expressed by recent international policy frameworks of OECD and WHO, and it addresses common misconceptions about the brain. The study suggests an update of the biology and science curriculum.

Future Thinking Priming Especially Effective at Modifying Delay Discounting Rates among Cigarette Smokers

BACKGROUND

Tobacco use remains one of the world's greatest preventable causes of death and disease. While most smokers want to quit, few are successful, highlighting a need for novel therapeutic approaches to support cessation efforts. Lower delay discounting (DD) rates are associated with increased smoking cessation success. Future thinking priming (FTP) reliably reduces DD rates in large populations. Smokers consistently discount more than nonsmokers, and evidence suggests that changes in DD rates are rate dependent. This study examined whether smoking status moderated the effect of FTP on DD rates and, if so, if the moderation effect could be attributed to differences in baseline rates of DD.

METHODS

Moderation analysis was conducted to determine whether the effect of FTP, versus neutral priming (NP), on DD differed among smokers and nonsmokers.

RESULTS

Smoking status moderated the effect of condition (FTP vs. NP) on post-intervention DD scores (b = -0.2919, p = 0.0124) and DD change scores (b = -0.2975, p = 0.0130). There was no evidence of rate dependence effects in the current sample.

CONCLUSIONS

FTP had a greater effect on decreasing DD rates among smokers than nonsmokers. FTP is effective and simple to administer, which makes it a promising therapeutic approach for aiding smoking cessation.

Exposure to the thin beauty ideal: Are there subliminal priming effects?

OBJECTIVE

Previous research suggested that exposure to the thin beauty ideal propagated by the media is associated with body dissatisfaction and the development of disordered eating. Given recent suggestions regarding the role of automatic processes, we aimed to enhance our understanding of automatic, unconscious responses to body pictures and the association with the internalization of the thin ideal and the severity of eating disorder symptoms.

METHOD

An affective priming task with body pictures of different weight as primes and a normal-weight body picture as target, which had to be evaluated with regard to attractiveness and desirability, was administered to healthy women with either subliminal prime presentation (Experiment 1) or conscious presentation (Experiment 2).

RESULTS

Subliminal presentation did not affect the evaluation of the normal-weight target, although strength of evaluative shifts was significantly associated with internalization of the thin ideal. In contrast, the conscious presentation of the ultra-thin prime decreased and of the obese prime increased desirability and attractiveness ratings of the target.

DISCUSSION

Prevention strategies focusing on the critical evaluation of the thin ideal are important. Future studies are warranted to enhance our understanding of automatic, unconscious processes in women experiencing eating disorders.

Gender differences in subliminal affective face priming: A high-density ERP study

INTRODUCTION

Subliminal affective priming effects (SAPEs) refer to the phenomenon by which the presentation of an affective prime stimulus influences the subsequent affective evaluation of a target stimulus. Previous studies have reported that unconsciously processed stimuli affect behavioral performance more than consciously processed stimuli. However, the impact of SAPEs on the face-specific N170 component is unclear. We studied how SAPEs for fearful faces affected the N170 for subsequent supraliminal target faces using event-related potentials (ERPs).

METHODS

Japanese adults (n = 44, 20 females) participated in this study. Subliminal prime faces (neutral or fearful) were presented for 17 ms, followed by a backward mask for 283 ms and 800 ms target faces (neutral, emotionally ambiguous, or fearful). 128-channel ERPs were recorded while participants judged the expression of target faces as neutral or fearful. Response rates and response times were also measured for assessing behavioral alterations.

RESULTS

Although the behavioral results revealed no evidence of SAPEs, we found gender-related SAPEs in right N170 amplitude. Specifically, female participants exhibited enhanced right N170 amplitude for emotionally neutral faces primed by fearful faces, while male participants exhibited decreased N170 amplitude in fearful prime trials with fearful target faces. Male participants exhibited significant correlations between N170 amplitude and behavioral response time in the fearful prime-neutral target condition.

CONCLUSIONS

Our ERP results suggest the existence of a gender difference in target-face processing preceded by subliminally presented face stimuli in the right occipito-temporal region.

Prime Movers: Effects of Subliminal Primes, Music, and Music Video on Psychological Responses to Exercise

BACKGROUND

Priming is a process in which exposure to a stimulus activates relevant mental representations that are given increased weight in subsequent judgment tasks. Affective primes can influence affective evaluations and associations. Such influence has meaningful implications for the promotion of exercise behavior, yet there is scant research on priming effects in exercise settings.

PURPOSE

The purpose of the present pair of studies was to examine the efficacy of music (M), music video (MV), and music video with affective primes (PRIME) in modulating psychological responses during and immediately following an exercise bout among two distinct populations.

METHODS

In Study 1, physically active participants completed a brisk walking task on a treadmill under four conditions: M, MV, PRIME, and control. Affective valence and rating of perceived exertion (RPE) were assessed during exercise and remembered/forecasted pleasure was measured immediately following each exercise bout. In Study 2, largely inactive and overweight participants completed a brisk walking task on a treadmill under two conditions: MV and PRIME. Affective valence was assessed during exercise, while exercise enjoyment and remembered/forecasted pleasure were assessed postexercise.

RESULTS

In Study 1, PRIME yielded more positively valenced affect, remembered/forecasted pleasure, and lower RPE when compared to the other conditions (MCohen's d for all DVs = 0.91). In Study 2, PRIME elicited more positively valenced affect, greater enjoyment, and enhanced remembered/forecasted pleasure when compared to MV (MCohen's d for all DVs = 0.64).

CONCLUSIONS

Subliminal primes embedded in music video can elicit positive changes in psychological responses during and immediately following exercise.

The assessment of views on ageing: a review of self-report measures and innovative extensions

This is a review of existing self-report measures for assessing views on ageing. It provides an overview of instruments, for which basic psychometric properties are available and describes them according to the purposes for which they are suitable. Literature search resulted in the inclusion of 89 instruments which were categorised along eight dimensions. The majority of measures focus on explicit cognitions about people's own age and ageing or other (older) people. A substantial amount of tools account for the multidimensionality and multidirectionality of views on ageing, i.e. the idea that ageing is accompanied by both gains and losses in several different domains. To some extent, measures reflect that ageing is a long-term process and that views on ageing are malleable, rather than just stable traits. Cluster analysis revealed heterogeneity in instruments regarding the dimensions of Ecosystem, Balance, Stability, Dynamics, and Complexity. It becomes apparent, however, that approaches to measure views on ageing should be extended to more specifically target the implicit level as well as affective, physiological, and behavioural manifestations. Additionally, means for capturing views on ageing on the societal level and tools with a distinct time reference are needed. This is particularly important when one wants to account for the lifelong dynamics of views on ageing.

Evidence against subliminal anchoring: Two close, highly powered, preregistered, and failed replication attempts

•The only two published studies on subliminal anchoring report contradictory results.•In two replications of these studies we could not find any evidence for subliminal anchoring.•Replications were as close as possible and high data quality was ensured, for example by introducing new manipulation checks.•Both our studies feature entirely open materials and preregistration of all materials including the analysis scripts. OPEN SCIENCE BADGES: Please grant all three badges, Preregistration, Open Materials, and Open Data.

Dissociating preferences from evaluations following subliminal conditioning

Preferences towards unfamiliar drink brands may be influenced through subliminal conditioning. This can involve associating unfamiliar brands (CS) with positively valenced attributes (US) under constrained visual conditions to prevent the former's conscious detection. According to learning theory, CS associated with positive US should become increasingly preferred as the latter's positive valences generalizes (transfer) across associated CS. Similarly, correlating CS with negative US should reduce CS-associated preferences. There is some evidence that CS-associated preferences can be reliably influenced through subliminal conditioning (Elgendi et al., 2018). Conversely, there is also evidence that subliminal conditioning does not effectively alter evaluations of CS valence (Heycke et al., 2018). Those works suggest CS preferences may be more susceptible to subliminal valence transfer relative to CS evaluations. We explored this hypothesis presently, where four pairs of supraliminal/visible and subliminal trigrams (CS) were respectively associated with four US categories varied along aggregate valence (100% positive, 80% positive, 20% positive, 0% positive). CS evaluations and preferences were recorded before and after conditioning. Bayesian analyses revealed US valence manipulations were likely to shift preferences, but not evaluations, of subliminal CS. Across supraliminal CS, Bayesian and frequentist analyses indicated US valence was significant and likely to shift preferences and evaluations. The present study demonstrates preferences may be influenced through subliminal conditioning even as evaluations are not.