Stimulus Onset Asynchrony Research Articles

Evidence for distinct steps in response preparation from a delayed response paradigm

Task parameters still affect reaction times even when all necessary information for executing an action is presented prior to a Go signal to execute the action. Hypotheses in terms of short-term memory capacity, residual activation, and a separate motor-programming stage have been suggested to explain what can and cannot be prepared prior to a delayed Go signal. To test these hypotheses, we used a delayed response task, in which participants were to initiate a movement at onset of an imperative Go signal following the target stimulus. Across Experiments 1–3 we varied task properties including stimulus type, information uncertainty and response complexity, respectively, while controlling other factors. We also varied the time available to process the response by randomly varying the interval between onset of the target and the Go signal (i.e., the stimulus onset asynchrony, or SOA). If the preparation process is completed before initiation, the examined factor should display a strong interaction with SOA, with its effect disappearing at long SOAs. Our results showed strong, weaker, and no interaction patterns for the three factors, respectively, favoring the separate stage hypothesis, according to which response preparation is separated into steps to arrange kinematic specifications into muscle-controllable terms.

Selection for encoding: No evidence of better endogenous orienting following forget than following remember instructions.

In an item-method directedforgetting task, attentional resources are withdrawn from forget item processing (e.g., Taylor & Fawcett in Attention, Perception, & Psychophysics, 73, 1790-1814, 2011). Taylor and Hamm (Attention, Perception, & Psychophysics, 78, 168-186, 2016) demonstrated that there is no corresponding increase in the proclivity for exogenous attention to be captured following a forget instruction. This means either that the attentional resources withdrawn from the forget item are reallocated immediately (and therefore not especially vulnerable to capture) or that it is not exogenous attention thatis withdrawn. Given that endogenous attention is distinct from exogenous attention, we therefore extended the Taylor and Hamm study by using endogenous orientingrather than exogenous orienting. Words appeared individually in a peripheral location (Exp. 1) or ina central location (Exp. 2), followed by an instruction to either remember or forget. After a short (50-ms) or long (250-ms) interstimulus interval (ISI), a central cue (80% accurate) directed participants to allocate their attention to the left or right. This was followed by a discrimination target that appeared at a 1,000-ms cue-target stimulus onset asynchrony. A subsequent yes-no recognition test assessed memory for all study items. In both experiments, we observed better recognition of remember wordsthan forget words-a directedforgetting effect. We also found a cueing effect, revealed as faster reaction times to discriminate cued targetsthan to discriminate uncued targets. There was not, however, an effect of memory instruction (and/or instruction-cue ISI) on the magnitude of this cueing effect. Thus, neither exogenous attentionnor endogenous attention remains in an unengaged state following an instruction to forget.

Inhibition of return (IOR) in patients with schizophrenia and cannabis use

Research concerning the spatial orientation in patients with schizophrenia has demonstrated a state independent deficit in inhibition of return (IOR), which has been discussed as a vulnerability marker for schizophrenia. Other recent investigations on brain structure and cognitive processing have revealed less deficits in schizophrenia patients with comorbid cannabis use (SCH + CUD) compared to abstinent schizophrenia patients (SCH). It was hypothesized that these results may reflect a premorbid lower vulnerability in at least a subgroup of comorbid patients. The aim of the present study is to extend previous work by investigating IOR functioning in patients with schizophrenia and cannabis use. This in turn should supplement the existing studies on the vulnerability of this patient group. Therefore, we compared IOR functioning in four groups: 62 patients with schizophrenia and 46 healthy controls, both with and without cannabis use. Participants underwent a covert orienting of attention task (COVAT) with peripheral cues and three stimulus onset asynchronies (SOAs: 200 ms, 400 ms and 800 ms). Both schizophrenia groups displayed delayed IOR with a more pronounced IOR effect in SCH + CUD compared to SCH. In healthy controls, IOR did not seem to be significantly affected by cannabis use. Significant IOR-differences between groups were only seen between SCH patients without cannabis use and both healthy groups at SOA 400 ms. Patterns of cannabis use as well as clinical parameters of psychoses did not affect IOR. Our results may support the hypothesis of IOR as a vulnerability marker for schizophrenia and of a lower biological vulnerability in at least a subgroup of SCH + CUD.

The Effects of Masking on the Detection of Alarms in Close Temporal Proximity

The Effects of Masking on the Detection of Alarms in Close Temporal Proximity

Learning new meanings for known words: Perturbation of original meanings and retention of new meanings.

Learning a new, unrelated meaning for a known word faces competition from the word's original meaning. Moreover, the connection of the word with its original meaning also shows a subtle form of interference, a perturbation, when tested immediately after learning. However, the long-term effects of both types of interference are unclear. The present study paired both high and low frequency words with new unrelated meanings, testing the fate of new and original meanings on three different days over one week as a function of word familiarity. The results were that learners maintained memory for new meanings of high frequency words better than the new meanings of low frequency words over one week. Following learning, meaning decisions on highfrequency words that required the original meaning of the trained word were delayed relative to decisions on control words - but only when testing was immediate and the stimulus-onset asynchrony (SOA) between the trained word and its original meaning probe was 200 ms. When the SOA was 500 ms or when the test was delayed by one day or one week, no effect occurred. The findings indicate that in the learning of new meanings for known words, word familiarity benefits long-term retention of new meanings. The facilitation effect occurs along with a perturbation effect, in which the original meaning of a familiar word is made momentarily less accessible immediately after learning.

Visual Dominance Effect upon Passing the Central Bottleneck of Information Processing.

Background:In the classical psychological refractory period (PRP) paradigm, two stimuli are presented in brief succession, and participants are asked to make separate speeded responses to both stimuli. Due to a central cognitive bottleneck, responses to the second stimulus are delayed, especially at short stimulus-onset asynchrony (SOA) between the two stimuli. Although the mechanisms of dual-task interference in the classical PRP paradigm have been extensively investigated, specific mechanisms underlying the cross-modal PRP paradigm are not well understood. In particular, it remains unknown whether the dominance of vision over audition manifests in the cross-modal PRP tasks. The present study aimed to investigate whether the visual dominance effect manifests in the cross-modal PRP paradigm.Methods:We adapted the classical PRP paradigm by manipulating the order of a visual and an auditory task: the visual task could either precede the auditory task or vice versa, at either short or long SOAs. Twenty-five healthy participants took part in Experiment 1, and thirty-three new participants took part in Experiment 2. Reaction time and accuracy data were calculated and further analyzed by repeated-measures analysis of variance.Results:The results showed that visual precedence in the Visual-Auditory condition caused larger impairments to the subsequent auditory processing than vice versa in the Auditory-Visual condition: a larger delay of second response was revealed in the Visual-Auditory condition (135 ± 10 ms) than the Auditory-Visual condition (88 ± 9 ms). This effect was found only at the short SOAs under the existence of the central bottleneck, but not at the long SOAs. Moreover, this effect occurred both when the single visual and the single auditory task were of equal difficulty in Experiment 1 and when the single auditory task was more difficult than the single visual task in Experiment 2.Conclusion:Results of the two experiments suggested that the visual dominance effect occurred under the central bottleneck of cognitive processing.

RT Slowing to Valid Cues on a Reflexive Attention Task in Children and Young Adults.

Peripheral cueing tasks can be used to measure reflexive (automatic) attention. In these tasks, increases in response time or RT (costs) typically follow contralateral (invalid) cues as attention must move from the location of the cue to the target. Reductions in RT (benefits) to a target typically follow ipsilateral (valid) cues because the cue draws attention to where the target will appear. Two exceptions to RT benefits are inhibition of return (IOR) and masking. IOR is the tendency to respond slower to targets that appear in locations attended within the last 200–2000 ms. Masking occurs when the visibility of a target is blocked by another stimulus (e.g., the cue). Herein, we describe two experiments, both using a modified Posner task with “earth rockets” as cues and “alien spaceships” as targets. Cues were equally likely to appear on the left or right side of a display following targets. Participants were instructed to press a left or right key corresponding to a left or right target. In Experiment 1, we obtained data from 203 children (10.58–16.55 years old). We discovered unexpected costs following cues that typically provide RT benefits. In Experiment 2, we explored IOR, masking, and age differences in the occurrence of these costs. We manipulated the cue-target temporal distance (“stimulus onset asynchrony” or SOA) to explore IOR and the cue-target spatial distance to explore masking. We also considered a wider age range. Sixty-three children and 41 young adults participated. Experiment 2 revealed a three-way interaction between SOA, spatial distance, and age. At the shorter SOA (100 ms) and moderate spatial distance, unexpected costs followed valid cues for younger children (7.07–10.15 years old). These costs also occurred in young adults (18.00–23.02 years old) following far distance cues at this SOA. At the longer SOA (200 ms), these costs followed moderate and far cues for younger children and near cues for young adults. Older children (10.31–14.92 years) did not have unexpected costs. We explain the findings in terms of masking, IOR, and possible developmental mechanisms.

Vestibular-somatosensory interactions affect the perceived timing of tactile stimuli.

Passive rotation has been shown to alter temporal-order judgments for tactile stimuli delivered to the hands giving an advantage to the leading hand. Here we measure thresholds for detecting stimulus onset asynchrony for touches on the hands during tilt to the left or right and during galvanic vestibular stimulation (GVS) that evoked illusory tilt. During tilt to one side, the effect of gravity on the otoliths is equivalent to a physical acceleration away from that side (e.g., tilt left is equivalent to accelerating rightwards). We therefore predicted a "leading hand advantage" for the hand opposite to the tilt direction. Thresholds for detecting asynchronicity for left-hand-first and right-hand-first touches (defined as correct detection 75% of the time) were measured separately using interleaved adaptive staircases for 15 participants. For both physical and illusory tilt there was a temporal advantage for stimuli presented to the hand contralateral to the tilt-equivalent to the "leading hand" during passive rotation. That is, there was a temporal advantage for the upward hand (for physical tilt) and for the anodal-side hand (for illusory tilt caused by GVS). These results are discussed in terms of attention and direct sensory components evoking the "leading hand" bias. These findings add to the emerging understanding of the pervasive role of vestibular activity in many aspects of cognitive processing.

Crowdsourced Measurement of Reaction Times to Audiovisual Stimuli With Various Degrees of Asynchrony.

Objective:This study was designed to replicate past research concerning reaction times to audiovisual stimuli with different stimulus onset asynchrony (SOA) using a large sample of crowdsourcing respondents.Background:Research has shown that reaction times are fastest when an auditory and a visual stimulus are presented simultaneously and that SOA causes an increase in reaction time, this increase being dependent on stimulus intensity. Research on audiovisual SOA has been conducted with small numbers of participants.Method:Participants (N = 1,823) each performed 176 reaction time trials consisting of 29 SOA levels and three visual intensity levels, using CrowdFlower, with a compensation of US$0.20 per participant. Results were verified with a local Web-in-lab study (N = 34).Results:The results replicated past research, with a V shape of mean reaction time as a function of SOA, the V shape being stronger for lower-intensity visual stimuli. The level of SOA affected mainly the right side of the reaction time distribution, whereas the fastest 5% was hardly affected. The variability of reaction times was higher for the crowdsourcing study than for the Web-in-lab study.Conclusion:Crowdsourcing is a promising medium for reaction time research that involves small temporal differences in stimulus presentation. The observed effects of SOA can be explained by an independent-channels mechanism and also by some participants not perceiving the auditory or visual stimulus, hardware variability, misinterpretation of the task instructions, or lapses in attention.Application:The obtained knowledge on the distribution of reaction times may benefit the design of warning systems.

P17. Impaired auditory attention in adolescents with developmental dyslexia

Theoretical background Developmental dyslexia (DD) refers to the pathological impairment in the acquisition of reading and/or writing skills that is not accounted for by biological age, intelligence or inadequate schooling (WHO, 2011). It is hypothesized that DD relies, at least in part, on the impaired ability to shift attention to relevant information (Hari and Renvall, 2001). On a neurophysiological level, attention is represented by alpha oscillations (about 8–12 Hz). In adults with DD, recent studies showed altered alpha oscillations during the processing of auditory and visual stimuli (Dhar et al., 2010) but also in resting state (Papagiannopoulou and Lagopoulos, 2016). However, until today, there is only sparse knowledge on auditory attention and the underlying neural mechanisms in adolescents with DD. Methods A sample of adolescents with diagnosed DD (Mean age: 14.29 years, SD: 1.46) and an age-matched control group (CG) participated in this study. In balanced order they performed two auditory spatial-cueing paradigms. In the exogenous paradigm, cue and target tones were presented monaurally at Stimulus onset Asynchrony (SOA) 100 ms and 250 ms. 50% of the trials consisted of valid cues. Catch trials (cue only) were intermittently presented. Participants had to respond as fast as possible whenever a target tone was presented. In the endogenous paradigm, cue and target tones were presented at SOAs between 1000 ms and 1500 ms. 80% of the trials consisted of valid cues. During both tasks EEG data was continuously recorded. Results While the CG showed an inhibition of return (IOR) i.e. reduced RT at invalid compared to valid cues with SOA 250 ms, no such effect was present in the DD sample. ERPs measured at the vertex electrode revealed prolonged peak latencies for target stimuli for both valid and invalid trials at SOA 250 ms in DD compared to CG. In the endogenous task, we found increased alpha desynchronization in the post-cue phase over left auditory cortex (AC) regions in DD compared to CG. Notably, this pattern was found irrespective of the site at which the cue was presented. Discussion The lack of an IOR in adolescents with DD demonstrates a decreased withdrawal of attention and suggests reduced orienting towards novel locations. Considering the endogenous task, our findings indicate a maladaptive inhibition of the left AC in DD that, in turn, might account for dysfunctional processing of incoming acoustic information. Our findings suggest altered auditory attention as potential basis for higher order language skills. Future studies investigating attention processes in pre-reading children will shed more light on whether attention is a cause of impaired language skills rather than the consequence of a maladaptive compensation over the course of reading/ writing acquisition.

Enhanced temporal binding of audiovisual information in the bilingual brain

We asked whether bilinguals’ benefits reach beyond the auditory modality to benefit multisensory processing. We measured audiovisual integration of auditory and visual cues in monolinguals and bilinguals via the double-flash illusion where the presentation of multiple auditory stimuli concurrent with a single visual flash induces an illusory perception of multiple flashes. We varied stimulus onset asynchrony (SOA) between auditory and visual cues to measure the “temporal binding window” where listeners fuse a single percept. Bilinguals showed faster responses and were less susceptible to the double-flash illusion than monolinguals. Moreover, monolinguals showed poorer sensitivity in AV processing compared to bilinguals. The width of bilinguals’ AV temporal integration window was narrower than monolinguals’ for both leading and lagging SOAs (Biling.: -65–112 ms; Mono.: -193 – 112 ms). Our results suggest the plasticity afforded by speaking multiple languages enhances multisensory integration and audiovisual binding in the bilingual brain.

Rapid recalibration to audiovisual asynchrony follows the physical-not the perceived-temporal order.

In natural scenes, audiovisual events deriving from the same source are synchronized at their origin. However, from the perspective of the observer, there are likely to be significant multisensory delays due to physical and neural latencies. Fortunately, our brain appears to compensate for the resulting latency differences by rapidly adapting to asynchronous audiovisual events by shifting the point of subjective synchrony (PSS) in the direction of the leading modality of the most recent event. Here we examined whether it is the perceived modality order of this prior lag or its physical order that determines the direction of the subsequent rapid recalibration. On each experimental trial, a brief tone pip and flash were presented across a range of stimulus onset asynchronies (SOAs). The participants' task alternated over trials: On adaptor trials, audition either led or lagged vision with fixed SOAs, and participants judged the order of the audiovisual event; on test trials, the SOA as well as the modality order varied randomly, and participants judged whether or not the event was synchronized. For test trials, we showed that the PSS shifted in the direction of the physical rather than the perceived (reported) modality order of the preceding adaptor trial. These results suggest that rapid temporal recalibration is determined by the physical timing of the preceding events, not by one's prior perceptual decisions.

An ERP Investigation of L2–L1 Translation Priming in Adult Learners

A longstanding debate centers around how beginning adult bilinguals process words in their second language (L2). Do they access the meaning of the L2 words directly or do they first activate the native language (L1) translation equivalents in order to access meaning? To address this question, we used ERPs to investigate how newly learned L2 words influence processing of their L1 translation equivalents. We taught participants the meanings of 80 novel L2 (pseudo)words by presenting them with pictures of familiar objects. After 3 days of learning, participants were tested in a backward translation priming paradigm with a short (140 ms) stimulus onset asynchrony. L1 targets preceded by their L2 translations elicited faster responses and smaller amplitude negativities than the same L1 targets preceded by unrelated L2 words. The bulk of the ERP translation priming effect occurred within the N400 window (350–550 ms), suggesting that the new L2 words were automatically activating their semantic representations. A weaker priming effect in the preceding window (200–350 ms) was found at anterior sites, providing some evidence that the forms of the L1 translation equivalents had also been activated. These results have implications for models of L2 processing at the earliest stages of learning.

Activation, Inhibition, or Something Else: An Exploratory Study on Response Priming Using Moving Dots as Primes in Middle-Aged and Old Adults.

Response priming refers to the finding that a prime stimulus preceding a target stimulus influences the response to the following target stimulus. With young subjects, using moving dot stimuli as primes indicated faster responses to compatible targets (i.e., prime and target are associated with the same response) with short stimulus onset asynchronies (SOAs). In contrast, with longer SOAs, participants responded faster to incompatible targets. In the present study, we extended the evidence by comparing middle-aged (50–65 years) and old (66–87 years) adults. With two different motion types, the result found in young participants was replicated in the middle-aged adults. In contrast, old adults showed large positive compatibility effects with the short SOA but neither activation nor inhibition effects with the longer SOA. We discuss our findings in light of several theoretical accounts (i.e., inhibitory deficit, deautomatization, evaluation window account, attention, rapid decay).

The contribution of perceptual factors and training on varying audiovisual integration capacity.

The suggestion that the capacity of audiovisual integration has an upper limit of 1 was challenged in 4 experiments using perceptual factors and training to enhance the binding of auditory and visual information. Participants were required to note a number of specific visual dot locations that changed in polarity when a critical auditory stimulus was presented, under relatively fast (200-ms stimulus onset asynchrony [SOA]) and slow (700-ms SOA) rates of presentation. In Experiment 1, transient cross-modal congruency between the brightness of polarity change and pitch of the auditory tone was manipulated. In Experiment 2, sustained chunking was enabled on certain trials by connecting varying dot locations with vertices. In Experiment 3, training was employed to determine if capacity would increase through repeated experience with an intermediate presentation rate (450 ms). Estimates of audiovisual integration capacity (K) were larger than 1 during cross-modal congruency at slow presentation rates (Experiment 1), during perceptual chunking at slow and fast presentation rates (Experiment 2), and, during an intermediate presentation rate posttraining (Experiment 3). Finally, Experiment 4 showed a linear increase in K using SOAs ranging from 100 to 600 ms, suggestive of quantitative rather than qualitative changes in the mechanisms in audiovisual integration as a function of presentation rate. The data compromise the suggestion that the capacity of audiovisual integration is limited to 1 and suggest that the ability to bind sounds to sights is contingent on individual and environmental factors. (PsycINFO Database Record

Developmental changes in the perception of visuotactile simultaneity

A simultaneity judgment (SJ) task was used to measure the developmental trajectory of visuotactile simultaneity perception in children (aged 7, 9, 11, and 13 years) and adults. Participants were presented with a visual flash in the center of a computer monitor and a tap on their right index finger (located 20° below the flash) with 13 possible stimulus onset asynchronies (SOAs). Participants reported whether the flash and tap were presented at the same time. Compared with the adult group, children aged 7 and 9 years made more simultaneous responses when the tap led by more than 300 ms and when the flash led by more than 200 ms, whereas they made fewer simultaneous responses at the 0 ms SOA. Model fitting demonstrated that the window of visuotactile simultaneity became narrower with development and reached adult-like levels between 9 and 11 years of age. Response errors decreased continuously until 11 years of age. The point of subjective simultaneity (PSS) was located on the tactile-leading side in all participants tested, indicating that 7-year olds (the youngest age tested) are adult-like on this measure. In summary, the perception of visuotactile simultaneity is not fully mature until 11 years of age. The protracted development of visuotactile simultaneity perception may be related to the need for crossmodal recalibration as the body grows and to the developmental improvements in the ability to optimally integrate visual and tactile signals.

An Tactile ERP-Based Brain–Computer Interface for Communication

ABSTRACTA classical visual event relative potential (ERP) brain–computer interface (BCI) system relies on visual stimuli to choose commands. Users obtain most information about their surroundings visually as well. This large amount of information can aggravate visual burden and fatigue. In our study, we proposed a novel approach to evoke ERP with a tactile stimulus. To achieve this approach, we first designed a wireless stimulus module with vibrators to provide a tactile stimulus for the system. The vibrators were located on the subject’s arm to imitate the joint motion of a robotic arm. Then, the ERP feature and the parameters of classifiers were obtained through offline experimental data analysis. Based on the analysis, the suitable electrode channels, stimulus onset asynchrony (SOA), and filter upper limit were different for different subjects. According to those outcomes, a unique classifier was designed for each subject. Finally, 10 healthy BCI-naive subjects participated in online experiments to evaluate the performance of our tactile BCI system; they achieved an accuracy range from 78.67% to 100% with an average of 89.1% and an instantaneous transmission rate (ITR) range from 7.77 to 28.70 bits/min with an average of 14.77 bits/min. The accuracy of different subjects and SOAs remained relatively stable, the ITR fluctuated mainly due to the different SOAs, and we achieved balance between ITR and accuracy.

Event-related potentials associated with cognitive mechanisms underlying lexical-semantic processing in monolingual and bilingual 18-month-old children

Prior to their second birthday, children are sensitive to the semantic relatedness between spoken words. Yet, it remains unclear whether simultaneous second language acquisition affects this sensitivity. Here, we investigated the influence of early acquisition of two languages on the event-related potentials (ERPs) associated with lexical-semantic processing of spoken words in 18-month-old monolingual and bilingual children. Children were exposed to an auditory semantic priming task in French, while their ERPs were recorded. Word pairs were either semantically related (e.g., train-bike) or unrelated (e.g., chicken-bike), and they were presented at two stimulus onset asynchronies (SOA). The results revealed that only monolingual children exhibited a semantic priming effect at the short SOA while at the long SOA condition, both monolingual and bilingual children exhibited more pronounced ERPs in response to unrelated compared with related target words. This finding suggests that both language groups are sensitive to taxonomic relations between words but activation of sematic network might be less automatized or slower in bilingual children.

A putative electrophysiological biomarker of auditory sensory memory encoding is sensitive to pharmacological alterations of excitatory/inhibitory balance in male macaque monkeys.

The amplitude of the auditory evoked N1 component that can be derived from noninvasive electroencephalographic recordings increases as a function of time between subsequent tones. N1 amplitudes in individuals with schizophrenia saturate at a lower asymptote, thus giving rise to a reduced dynamic range. Reduced N1 dynamic range is a putative electrophysiological biomarker of altered sensory memory function in individuals with the disease. To date, it is not clear what determines N1 dynamic range and what causes reduced N1 dynamic range in individuals with schizophrenia. Here we test the hypothesis that reduced N1 dynamic range results from a shift in excitatory/inhibitory (E/I) balance toward an excitation-deficient or inhibition-dominant state. We recorded auditory-evoked potentials (AEPs) while 4 macaque monkeys passively listened to sequences of sounds of random pitch and stimulus-onset asynchrony (SOA). Three independent experiments tested the effect of the N-methyl-d-aspartate receptor channel blockers ketamine and MK-801 as well as the γ-aminobutyric acid (GABA) A receptor-positive allosteric modulator midazolam on the dynamic range of a putative monkey N1 homologue and 4 other AEP components. Ketamine, MK-801 and midazolam reduced peak N1 amplitudes for the longest SOAs. Other AEP components were also affected, but revealed distinct patterns of susceptibility for the glutamatergic and GABA-ergic drugs. Different patterns of susceptibility point toward differences in the circuitry maintaining E/I balance of individual components. The study used systemic pharmacological interventions that may have acted on targets outside of the auditory cortex. The N1 dynamic range may be a marker of altered E/I balance. Reduced N1 dynamic range in individuals with schizophrenia may indicate that the auditory cortex is in an excitation-deficient or inhibition-dominant state. This may be the result of an incomplete compensation for a primary deficit in excitatory drive.

Seeing it both ways: Using a double-cuing task to investigate the role of spatial cuing in Level-1 visual perspective-taking.

Previous research using the dot-perspective task has produced evidence that humans may be equipped with a mechanism that spontaneously tracks others' gaze direction and thereby acquires information about what they can see. Other findings, however, support the alternative hypothesis that a spatial-cuing mechanism underpins the effect observed in the dot-perspective task. To adjudicate between these hypotheses, we developed a double-cuing version of Posner's (1980) spatial-cuing paradigm to be implemented in the dot-perspective task, and conducted 3 experiments in which we manipulated stimulus-onset asynchrony, as well as secondary task demands. Crucially, the 2 conflicting hypotheses generated divergent patterns of predictions across these experimental conditions. Our results support the hypothesis of an automatic perspective-taking mechanism. (PsycINFO Database Record