A functional promoter variant of the human formimidoyltransferase cyclodeaminase (FTCD) gene is associated with working memory performance in young but not older adults.

OBJECTIVE: The central role of working memory in IQ and the high heritability of working memory performance motivated interest in identifying the specific genes underlying this heritability. The FTCD (formimidoyltransferase cyclodeaminase) gene was identified as a candidate gene for allelic association with working memory in part from genetic mapping studies of mouse Morris water maze performance. METHOD: The present study tested variants of this gene for effects on a delayed match-to-sample task of a large sample of younger and older participants. RESULTS: The rs914246 variant, but not the rs914245 variant, of the FTCD gene modulated accuracy in the task for younger, but not older, people under high working memory load. The interaction of haplotype × distance × load had a partial eta squared effect size of 0.015. Analysis of simple main effects had partial eta squared effect sizes ranging from 0.012 to 0.040. A reporter gene assay revealed that the C allele of the rs914246 genotype is functional and a main factor regulating FTCD gene expression. CONCLUSION: This study extends previous work on the genetics of working memory by revealing that a gene in the glutamatergic pathway modulates working memory in young people but not in older people. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Individual differences in learning correlate with modulation of brain activity induced by transcranial direct current stimulation.

Transcranial direct current stimulation (tDCS) has been shown to enhance cognitive performance on a variety of tasks. It is hypothesized that tDCS enhances performance by affecting task related cortical excitability changes in networks underlying or connected to the site of stimulation facilitating long term potentiation. However, many recent studies have called into question the reliability and efficacy of tDCS to induce modulatory changes in brain activity. In this study, our goal is to investigate the individual differences in tDCS induced modulatory effects on brain activity related to the degree of enhancement in performance, providing insight into this lack of reliability. In accomplishing this goal, we used functional magnetic resonance imaging (fMRI) concurrently with tDCS stimulation (1 mA, 30 minutes duration) using a visual search task simulating real world conditions. The experiment consisted of three fMRI sessions: pre-training (no performance feedback), training (performance feedback which included response accuracy and target location and either real tDCS or sham stimulation given), and post-training (no performance feedback). The right posterior parietal cortex was selected as the site of anodal tDCS based on its known role in visual search and spatial attention processing. Our results identified a region in the right precentral gyrus, known to be involved with visual spatial attention and orienting, that showed tDCS induced task related changes in cortical excitability that were associated with individual differences in improved performance. This same region showed greater activity during the training session for target feedback of incorrect (target-error feedback) over correct trials for the tDCS stim over sham group indicating greater attention to target features during training feedback when trials were incorrect. These results give important insight into the nature of neural excitability induced by tDCS as it relates to variability in individual differences in improved performance shedding some light the apparent lack of reliability found in tDCS research.

A Little Anthropomorphism Goes a Long Way.

OBJECTIVE: We investigated the effects of exogenous oxytocin on trust, compliance, and team decision making with agents varying in anthropomorphism (computer, avatar, human) and reliability (100%, 50%). BACKGROUND: Authors of recent work have explored psychological similarities in how people trust humanlike automation compared with how they trust other humans. Exogenous administration of oxytocin, a neuropeptide associated with trust among humans, offers a unique opportunity to probe the anthropomorphism continuum of automation to infer when agents are trusted like another human or merely a machine. METHOD: Eighty-four healthy male participants collaborated with automated agents varying in anthropomorphism that provided recommendations in a pattern recognition task. RESULTS: Under placebo, participants exhibited less trust and compliance with automated aids as the anthropomorphism of those aids increased. Under oxytocin, participants interacted with aids on the extremes of the anthropomorphism continuum similarly to placebos but increased their trust, compliance, and performance with the avatar, an agent on the midpoint of the anthropomorphism continuum. CONCLUSION: This study provides the first evidence that administration of exogenous oxytocin affected trust, compliance, and team decision making with automated agents. These effects provide support for the premise that oxytocin increases affinity for social stimuli in automated aids. APPLICATION: Designing automation to mimic basic human characteristics is sufficient to elicit behavioral trust outcomes that are driven by neurological processes typically observed in human-human interactions. Designers of automated systems should consider the task, the individual, and the level of anthropomorphism to achieve the desired outcome.

Prefrontal Hemodynamics of Physical Activity and Environmental Complexity During Cognitive Work.

OBJECTIVE: The aim of this study was to assess performance and cognitive states during cognitive work in the presence of physical work and in natural settings. BACKGROUND: Authors of previous studies have examined the interaction between cognitive and physical work, finding performance decrements in working memory. Neuroimaging has revealed increases and decreases in prefrontal oxygenated hemoglobin during the interaction of cognitive and physical work. The effect of environment on cognitive-physical dual tasking has not been previously considered. METHOD: Thirteen participants were monitored with wireless functional near-infrared spectroscopy (fNIRS) as they performed an auditory 1-back task while sitting, walking indoors, and walking outdoors. RESULTS: Relative to sitting and walking indoors, auditory working memory performance declined when participants were walking outdoors. Sitting during the auditory 1-back task increased oxygenated hemoglobin and decreased deoxygenated hemoglobin in bilateral prefrontal cortex. Walking reduced the total hemoglobin available to bilateral prefrontal cortex. An increase in environmental complexity reduced oxygenated hemoglobin and increased deoxygenated hemoglobin in bilateral prefrontal cortex. CONCLUSION: Wireless fNIRS is capable of monitoring cognitive states in naturalistic environments. Selective attention and physical work compete with executive processing. During executive processing loading of selective attention and physical work results in deactivation of bilateral prefrontal cortex and degraded working memory performance, indicating that physical work and concomitant selective attention may supersede executive processing in the distribution of mental resources. APPLICATION: This research informs decision-making procedures in work where working memory, physical activity, and attention interact. Where working memory is paramount, precautions should be taken to eliminate competition from physical work and selective attention.

An fMRI and effective connectivity study investigating miss errors during advice utilization from human and machine agents.

As society becomes more reliant on machines and automation, understanding how people utilize advice is a necessary endeavor. Our objective was to reveal the underlying neural associations during advice utilization from expert human and machine agents with fMRI and multivariate Granger causality analysis. During an X-ray luggage-screening task, participants accepted or rejected good or bad advice from either the human or machine agent framed as experts with manipulated reliability (high miss rate). We showed that the machine-agent group decreased their advice utilization compared to the human-agent group and these differences in behaviors during advice utilization could be accounted for by high expectations of reliable advice and changes in attention allocation due to miss errors. Brain areas involved with the salience and mentalizing networks, as well as sensory processing involved with attention, were recruited during the task and the advice utilization network consisted of attentional modulation of sensory information with the lingual gyrus as the driver during the decision phase and the fusiform gyrus as the driver during the feedback phase. Our findings expand on the existing literature by showing that misses degrade advice utilization, which is represented in a neural network involving salience detection and self-processing with perceptual integration.

Advice Taking from Humans and Machines: An fMRI and Effective Connectivity Study.

With new technological advances, advice can come from different sources such as machines or humans, but how individuals respond to such advice and the neural correlates involved need to be better understood. We combined functional MRI and multivariate Granger causality analysis with an X-ray luggage-screening task to investigate the neural basis and corresponding effective connectivity involved with advice utilization from agents framed as experts. Participants were asked to accept or reject good or bad advice from a human or machine agent with low reliability (high false alarm rate). We showed that unreliable advice decreased performance overall and participants interacting with the human agent had a greater depreciation of advice utilization during bad advice compared to the machine agent. These differences in advice utilization can be perceivably due to reevaluation of expectations arising from association of dispositional credibility for each agent. We demonstrated that differences in advice utilization engaged brain regions that may be associated with evaluation of personal characteristics and traits (precuneus, posterior cingulate cortex, temporoparietal junction) and interoception (posterior insula). We found that the right posterior insula and left precuneus were the drivers of the advice utilization network that were reciprocally connected to each other and also projected to all other regions. Our behavioral and neuroimaging results have significant implications for society because of progressions in technology and increased interactions with machines.

Almost human: Anthropomorphism increases trust resilience in cognitive agents.

We interact daily with computers that appear and behave like humans. Some researchers propose that people apply the same social norms to computers as they do to humans, suggesting that social psychological knowledge can be applied to our interactions with computers. In contrast, theories of human­automation interaction postulate that humans respond to machines in unique and specific ways. We believe that anthropomorphism­the degree to which an agent exhibits human characteristics­is the critical variable that may resolve this apparent contradiction across the formation, violation, and repair stages of trust. Three experiments were designed to examine these opposing viewpoints by varying the appearance and behavior of automated agents. Participants received advice that deteriorated gradually in reliability from a computer, avatar, or human agent. Our results showed (a) that anthropomorphic agents were associated with greater trust resilience, a higher resistance to breakdowns in trust; (b) that these effects were magnified by greater uncertainty; and c) that incorporating human-like trust repair behavior largely erased differences between the agents. Automation anthropomorphism is therefore a critical variable that should be carefully incorporated into any general theory of human­agent trust as well as novel automation design.

Into the Wild: Neuroergonomic Differentiation of Hand-Held and Augmented Reality Wearable Displays during Outdoor Navigation with Functional Near Infrared Spectroscopy.

Highly mobile computing devices promise to improve quality of life, productivity, and performance. Increased situation awareness and reduced mental workload are two potential means by which this can be accomplished. However, it is difficult to measure these concepts in the "wild". We employed ultra-portable battery operated and wireless functional near infrared spectroscopy (fNIRS) to non-invasively measure hemodynamic changes in the brain's Prefrontal cortex (PFC). Measurements were taken during navigation of a college campus with either a hand-held display, or an Augmented reality wearable display (ARWD). Hemodynamic measures were also paired with secondary tasks of visual perception and auditory working memory to provide behavioral assessment of situation awareness and mental workload. Navigating with an augmented reality wearable display produced the least workload during the auditory working memory task, and a trend for improved situation awareness in our measures of prefrontal hemodynamics. The hemodynamics associated with errors were also different between the two devices. Errors with an augmented reality wearable display were associated with increased prefrontal activity and the opposite was observed for the hand-held display. This suggests that the cognitive mechanisms underlying errors between the two devices differ. These findings show fNIRS is a valuable tool for assessing new technology in ecologically valid settings and that ARWDs offer benefits with regards to mental workload while navigating, and potentially superior situation awareness with improved display design.

The Brain Is Faster than the Hand in Split-Second Intentions to Respond to an Impending Hazard: A Simulation of Neuroadaptive Automation to Speed Recovery to Perturbation in Flight Attitude.

The goal of this research is to test the potential for neuroadaptive automation to improve response speed to a hazardous event by using a brain-computer interface (BCI) to decode perceptual-motor intention. Seven participants underwent four experimental sessions while measuring brain activity with magnetoencephalograpy. The first three sessions were of a simple constrained task in which the participant was to pull back on the control stick to recover from a perturbation in attitude in one condition and to passively observe the perturbation in the other condition. The fourth session consisted of having to recover from a perturbation in attitude while piloting the plane through the Grand Canyon constantly maneuvering to track over the river below. Independent component analysis was used on the first two sessions to extract artifacts and find an event related component associated with the onset of the perturbation. These two sessions were used to train a decoder to classify trials in which the participant recovered from the perturbation (motor intention) vs. just passively viewing the perturbation. The BCI-decoder was tested on the third session of the same simple task and found to be able to significantly distinguish motor intention trials from passive viewing trials (mean = 69.8%). The same BCI-decoder was then used to test the fourth session on the complex task. The BCI-decoder significantly classified perturbation from no perturbation trials (73.3%) with a significant time savings of 72.3 ms (Original response time of 425.0-352.7 ms for BCI-decoder). The BCI-decoder model of the best subject was shown to generalize for both performance and time savings to the other subjects. The results of our off-line open loop simulation demonstrate that BCI based neuroadaptive automation has the potential to decode motor intention faster than manual control in response to a hazardous perturbation in flight attitude while ignoring ongoing motor and visual induced activity related to piloting the airplane.

Individual differences in reasoning and visuospatial attention are associated with prefrontal and parietal white matter tracts in healthy older adults.

OBJECTIVE: Although reasoning and attention are 2 cognitive processes necessary for ensuring the efficiency of many everyday activities in older adults, the role of white matter integrity in these processes has been little studied. This is an important question due to the role of white matter integrity as a neural substrate of cognitive aging. Here, we sought to examine the white matter tracts subserving reasoning and visuospatial attention in healthy older adults. METHOD: Sixty-one adults ages 60 and older completed a battery of cognitive tests to assess reasoning and visuospatial attention. In addition, diffusion tensor images were collected to assess fractional anisotropy (FA), a measure of white matter integrity. A principle components analysis of the test scores yielded 2 components: reasoning and visuospatial attention. Whole-brain correlations between FA and the cognitive components were submitted to probabilistic tractography analyses for visualization of cortical targets of tracts. RESULTS: For reasoning, bilateral thalamo-anterior prefrontal, anterior corpus callosum, and corpus callosum body tracts interconnecting the superior frontal cortices and right cingulum bundle were found. For visuospatial attention, a right inferior fronto-parietal tract and bilateral parietal and temporal connections were found. CONCLUSIONS: We conclude that in older adults, prefrontal cortex white matter tracts and interhemispheric communication are important in higher order cognitive functioning. On the other hand, right-sided fronto-parietal tracts appear to be critical for supporting control of cognitive processes, such as redirecting attention. Researchers may use our results to develop neuroscience-based interventions for older adults targeting brain mechanisms involved in cognitive plasticity. (PsycINFO Database Record

Simultaneous tDCS-fMRI Identifies Resting State Networks Correlated with Visual Search Enhancement.

This study uses simultaneous transcranial direct current stimulation (tDCS) and functional MRI (fMRI) to investigate tDCS modulation of resting state activity and connectivity that underlies enhancement in behavioral performance. The experiment consisted of three sessions within the fMRI scanner in which participants conducted a visual search task: Session 1: Pre-training (no performance feedback), Session 2: Training (performance feedback given), Session 3: Post-training (no performance feedback). Resting state activity was recorded during the last 5 min of each session. During the 2nd session one group of participants underwent 1 mA tDCS stimulation and another underwent sham stimulation over the right posterior parietal cortex. Resting state spontaneous activity, as measured by fractional amplitude of low frequency fluctuations (fALFF), for session 2 showed significant differences between the tDCS stim and sham groups in the precuneus. Resting state functional connectivity from the precuneus to the substantia nigra, a subcortical dopaminergic region, was found to correlate with future improvement in visual search task performance for the stim over the sham group during active stimulation in session 2. The after-effect of stimulation on resting state functional connectivity was measured following a post-training experimental session (session 3). The left cerebellum Lobule VIIa Crus I showed performance related enhancement in resting state functional connectivity for the tDCS stim over the sham group. The ability to determine the relationship that the relative strength of resting state functional connectivity for an individual undergoing tDCS has on future enhancement in behavioral performance has wide ranging implications for neuroergonomic as well as therapeutic, and rehabilitative applications.

Oxytocin influences intuitions about the relationship between belief in free will and moral responsibility.

Philosophers have proposed that laypeople can have deterministic or indeterministic intuitions about the relationship between free will and moral responsibility. However, the psychophysiological mechanisms that generate these extreme intuitions are still underexplored. Exogenous oxytocin offers a unique opportunity to gain a deeper understanding of these underlying mechanisms, since this neuropeptide influences a wide range of outcomes related to social cognition and prosociality. This study investigated the effects of intranasal oxytocin on intuitions about the relationship between free will and moral responsibility by applying a randomized, double-blind, placebo-controlled, between-subject design. Healthy male participants rated the moral responsibility of a hypothetical offender, who committed crimes in either a primed deterministic or an indeterministic universe. Under placebo, participants held the offender more morally responsible when acting in an indeterministic compared to a deterministic universe, which could be accredited to recognition of the offender's freely chosen action to commit the crimes. Under oxytocin, participants rated the offender's actions with greater leniency and similarly assigned lower moral responsibility in both universes. These findings strengthen the assumption that a person can have different intuitions about the relationship between free will and moral responsibility, which can be presumably dependent on motivational states associated with affiliation.

Uncertainty-dependent activity within the ventral striatum predicts task-related changes in response strategy.

Recent neuroimaging work has demonstrated that the ventral striatum (VS) encodes confidence in perceptual decisions. However, it remains unclear whether perceptual uncertainty can signal the need to adapt behavior (such as by responding more cautiously) and whether such behavioral changes are related to uncertainty-dependent activity within the VS. Changes in response strategy have previously been observed following errors and are associated with both medial frontal cortex (MFC) and VS, two components of the performance-monitoring network. If uncertainty can elicit changes in response strategy (slowing), then one might hypothesize that these changes rely on the performance-monitoring network. In the present study, we investigated the link between perceptual uncertainty and task-related behavioral adaptations (response slowing and accuracy increases), as well as how such behavioral changes relate to uncertainty-dependent activity within MFC and VS. Our participants performed a two-choice perceptual decision-making task in which perceptual uncertainty was reported on each trial while behavioral and event-related functional magnetic resonance imaging data were collected. Analysis of the behavioral data revealed that uncertain (but correct) responses led to slowing on subsequent trials, a phenomenon that was positively correlated with increased accuracy. Critically, post-uncertainty slowing was negatively correlated with the VS activity elicited by uncertain responses. In agreement with previous reports, increases in MFC activation were observed for uncertain responses, although MFC activity was not correlated with post-uncertainty slowing. These results suggest that perceptual uncertainty can serve as a signal to adapt one's response strategy and that such behavioral changes are closely tied to the VS, a key node in the performance-monitoring network.

The mechanisms of far transfer from cognitive training: Review and hypothesis.

OBJECTIVE: General intelligence is important for success in daily life, fueling interest in developing cognitive training as an intervention to improve fluid ability (Gf). A major obstacle to the design of effective cognitive interventions has been the paucity of hypotheses bearing on mechanisms underlying transfer of cognitive training to Gf. Despite the large amounts of money and time currently being expended on cognitive training, there is little scientific agreement on how, or even whether, Gf can be heightened by such training. METHOD: We review the relevant strands of evidence on cognitive-training-related changes in (a) cortical mechanisms of distraction suppression, and (b) activation of the dorsal attention network (DAN). We hypothesize that training-related increases in control of attention are important for what is termed far transfer of cognitive training to untrained abilities, notably to Gf. RESULTS: We review the evidence that distraction suppression evident in behavior, neuronal firing, scalp electroencephalography, and hemodynamic change is important for protecting target processing during perception and also for protecting targets held in working memory. Importantly, attentional control also appears to be central to performance on Gf assessments. Consistent with this evidence, forms of cognitive training that increase ability to ignore distractions (e.g., working memory training and perceptual training) not only affect the DAN but also affect transfer to Gf. CONCLUSIONS: Our hypothesis is supported by existing evidence. However, to advance the field of cognitive training, it is necessary that competing hypotheses on mechanisms of far transfer of cognitive training be advanced and empirically tested. (PsycINFO Database Record

The Visual Priming of Motion-Defined 3D Objects.

The perception of a stimulus can be influenced by previous perceptual experience, a phenomenon known as perceptual priming. However, there has been limited investigation on perceptual priming of shape perception of three-dimensional object structures defined by moving dots. Here we examined the perceptual priming of a 3D object shape defined purely by motion-in-depth cues (i.e., Shape-From-Motion, SFM) using a classic prime-target paradigm. The results from the first two experiments revealed a significant increase in accuracy when a "cloudy" SFM stimulus (whose object structure was difficult to recognize due to the presence of strong noise) was preceded by an unambiguous SFM that clearly defined the same transparent 3D shape. In contrast, results from Experiment 3 revealed no change in accuracy when a "cloudy" SFM stimulus was preceded by a static shape or a semantic word that defined the same object shape. Instead, there was a significant decrease in accuracy when preceded by a static shape or a semantic word that defined a different object shape. These results suggested that the perception of a noisy SFM stimulus can be facilitated by a preceding unambiguous SFM stimulus--but not a static image or a semantic stimulus--that defined the same shape. The potential neural and computational mechanisms underlying the difference in priming are discussed.

Reducing the Disruptive Effects of Interruptions With Noninvasive Brain Stimulation.

OBJECTIVE: The authors determine whether transcranial direct current stimulation (tDCS) can reduce resumption time when an ongoing task is interrupted. BACKGROUND: Interruptions are common and disruptive. Working memory capacity has been shown to predict resumption lag (i.e., time to successfully resume a task after interruption). Given that tDCS applied to brain areas associated with working memory can enhance performance, tDCS has the potential to improve resumption lag when a task is interrupted. METHOD: Participants were randomly assigned to one of four groups that received anodal (active) stimulation of 2 mA tDCS to one of two target brain regions, left and right dorsolateral prefrontal cortex (DLPFC), or to one of two control areas, active stimulation of the left primary motor cortex or sham stimulation of the right DLPFC, while completing a financial management task that was intermittently interrupted with math problem solving. RESULTS: Anodal stimulation to the right and left DLPFC significantly reduced resumption lags compared to the control conditions (sham and left motor cortex stimulation). Additionally, there was no speed-accuracy tradeoff (i.e., the improvement in resumption time was not accompanied by an increased error rate). CONCLUSION: Noninvasive brain stimulation can significantly decrease resumption lag (improve performance) after a task is interrupted. APPLICATION: Noninvasive brain stimulation offers an easy-to-apply tool that can significantly improve interrupted task performance.

Wearable functional near infrared spectroscopy (fNIRS) and transcranial direct current stimulation (tDCS): expanding vistas for neurocognitive augmentation.

Contemporary studies with transcranial direct current stimulation (tDCS) provide a growing base of evidence for enhancing cognition through the non-invasive delivery of weak electric currents to the brain. The main effect of tDCS is to modulate cortical excitability depending on the polarity of the applied current. However, the underlying mechanism of neuromodulation is not well understood. A new generation of functional near infrared spectroscopy (fNIRS) systems is described that are miniaturized, portable, and include wearable sensors. These developments provide an opportunity to couple fNIRS with tDCS, consistent with a neuroergonomics approach for joint neuroimaging and neurostimulation investigations of cognition in complex tasks and in naturalistic conditions. The effects of tDCS on complex task performance and the use of fNIRS for monitoring cognitive workload during task performance are described. Also explained is how fNIRS + tDCS can be used simultaneously for assessing spatial working memory. Mobile optical brain imaging is a promising neuroimaging tool that has the potential to complement tDCS for realistic applications in natural settings.

Enhancing multiple object tracking performance with noninvasive brain stimulation: a causal role for the anterior intraparietal sulcus.

Multiple object tracking (MOT) is a complex task recruiting a distributed network of brain regions. There are also marked individual differences in MOT performance. A positive causal relationship between the anterior intraparietal sulcus (AIPS), an integral region in the MOT attention network and inter-individual variation in MOT performance has not been previously established. The present study used transcranial direct current stimulation (tDCS), a form of non-invasive brain stimulation, in order to examine such a causal link. Active anodal stimulation was applied to the right AIPS and the left dorsolateral prefrontal cortex (DLPFC) (and sham stimulation), an area associated with working memory (but not MOT) while participants completed a MOT task. Stimulation to the right AIPS significantly improved MOT accuracy more than the other two conditions. The results confirm a causal role of the AIPS in the MOT task and illustrate that tDCS has the ability to improve MOT performance.

The sustained attention to response task (SART) does not promote mindlessness during vigilance performance.

OBJECTIVE: In this study, we evaluated the validity of the Sustained Attention to Response Task (SART) as a means for promoting mindlessness in vigilance performance. BACKGROUND: Vigilance tasks typically require observers to respond to critical signals and to withhold responding to neutral events. The SART features the opposite response requirements, which supposedly leads it to promote a mindless, non-thoughtful approach to the vigilance task To test that notion, we compared the SART to the traditional vigilance format (TVF) in terms of diagnostic accuracy assessed through decision theory measures of positive and negative predictive power (PPP and NPP), perceived mental workload indexed by the Multiple Resource Questionnaire, and oculomotor activity reflected in the Nearest Neighbor Index and fixation dwell times. METHOD: Observers in TVF and SART conditions monitored a video display for collision flight paths in a simulated air traffic control task. RESULTS: Diagnostic accuracy in terms of NPP was high in both format conditions. While PPP was poorer in the SART than in the TVF, that result could be accounted for by a loss of motor control rather than a lack of mindfulness. Identical high levels of workload were generated by the TVF and SART tasks, and observers in both conditions showed similar dynamic scanning of the visual scene. CONCLUSION: The data indicate that the SART is not an engine of mindlessness. APPLICATION: The results challenge the widespread use of the SART to support a model in which mindlessness is considered to be the principal root of detection failures in vigilance.

What you see depends on what you saw, and what else you saw: the interactions between motion priming and object priming.

Both visual object priming and motion priming have been reported independently, but the interactions between the two are still largely unexplored. Here we investigated this question using a novel type of SFM stimuli, 3-D helixes, and found that the motion direction perception of an ambiguous helix can be biased by the motion direction of a preceding SFM stimulus - a classic motion priming effect. However, the effectiveness of motion priming depends on object priming: a neutral object priming produced a weak motion priming, a congruent object priming led to a strong motion priming, and critically, an incongruent object priming abolished and overpowered the motion priming. In contrast, object priming alone (in the absence of motion overlap) had little effects biasing motion perception. Taken together, these results suggest that there exists an integrated neural representation of motion and structure of 3-D SFM stimuli, and motion priming of 3-D SFM stimuli might happen at an intermediate stage between MT/V5 (which is not shape selective) and LO (lateral occipital, which is not motion selective). This novel type of stimuli, 3-D helixes, along with the prime-target paradigm, thus might offer a unique tool to examine neural bases underlying the perception of 3-D SFM stimuli and perceptual priming.