Metacognition of agency and theory of mind in adults with high functioning autism

We investigated metacognition of agency in adults with high functioning autism or Asperger Syndrome (HFA/AS) using a computer task in which participants moved the mouse to get the cursor to touch the downward moving X’s and avoid the O’s. They were then asked to make judgments of performance and judgments of agency. Objective control was either undistorted, or distorted by adding turbulence (i.e., random noise) or a time Lag between the mouse and cursor movements. Participants with HFA/AS used sensorimotor cues available in the turbulence and lag conditions to a lesser extent than control participants in making their judgments of agency. Furthermore, the failure to use these internal diagnostic cues to their own agency was correlated with decrements in a theory of mind task. These findings suggest that a reduced sensitivity to veridical internal cues about the sense of agency is related to mentalizing impairments in autism.     

On the Role of Vertical Texture Cues in Height Perception

When people judge height from the top looking down they tend to overestimate vertical distance. Initial findings suggest that this perceptual bias may be in part due to the experienced fear of falling. However, previous studies did not control for potentially relevant optical invariants, especially vertical texture gradient cues, that may inform such perceptual judgments. In this study, we examined to what degree texture gradient cues may account for the perceptual bias in height perception. To this end, in 2 different conditions in which vertical texture gradient cues were either present or absent, participants provided distance and size judgments from an elevated position (5.68 m) and from the ground. Results revealed a systematic overestimation of vertical extent and object size when judged from a height. Yet, the absence or presence of texture gradient cues did not differentially influence these judgments. Finally, although fear levels were reported to be larger at the elevated position than on the ground, fear levels did not correlate with the perceptual bias, thereby demanding further research into the mechanisms underlying the perceptual bias in height perception.     

Inferring agency from sound

In three experiments we investigated how people determine whether or not they are in control of sounds they hear. The sounds were either triggered by participants’ taps or controlled by a computer. The task was to distinguish between self-control and external control during active tapping, and during passive listening to a playback of the sounds recorded during the active condition. Experiment 1 required detection of a change in control mode within trials. Experiments 2 and 3 introduced a simple rhythm reproduction task that requires discrimination of control modes between trials. The results demonstrate that both sensorimotor cues and perceptual cues are used to infer agency. In addition, there may be further influences of cognitive expectation and/or multimodal integration. In accordance with hierarchical models of intention [e.g., Pacherie, E. (2008). The phenomenology of action: A conceptual framework. Cognition, 107, 179-217] this suggests that the sense of agency is not situated on one specific level of action control but subject to multiple influences.     

Evaluation of a novel translational task for assessing emotional biases in different species

Changes in the processing of emotional information are key features of affective disorders. Neuropsychological tests based on emotional faces or words are used to detect emotional/affective biases in humans, but these tests are not applicable to animal species. In the present study, we investigated whether a novel affective tone discrimination task (ATDT), developed to study emotion-related behaviour in rats, could also be used to quantify changes in affective states in humans. To date, the methods used in human neuropsychology have not been applicable to animal experiments. Participants completed a training session in which they learnt to discriminate specific tone frequencies and to correctly respond in order to gain emotionally valenced outcomes, to obtain rewards (money), or to avoid punishment (an aversive sound clip). During a subsequent test session, additional ambiguous probe tones were presented at frequencies intermediate between the reward and avoidance paired tones. At the end of the task, participants completed self-report questionnaires. All participants made more avoidance responses to the most ambiguous tone cues, suggesting a bias towards avoidance of punishment. Individual differences in the degrees of bias observed were correlated with anxiety measures, suggesting the task’s sensitivity to differences in state anxiety within a healthy population. Further studies in clinical populations will be necessary to assess the task’s sensitivity to pathological anxiety states. These data suggest that this affective tone discrimination task provides a novel method to study cognitive affective biases in different species, including humans, and offers a novel assessment to study anxiety.     

Effects of Phonetic Similarity in the Identification of Mandarin Tones

Tonal languages differ in how they use phonetic correlates e.g. average pitch height and pitch direction, for tonal contrasts. Thus, native speakers of a tonal language may need to adjust their attention to familiar or unfamiliar phonetic cues when perceiving non-native tones. On the other hand, speakers of a non-tonal language may need to develop sensitivity to tonal correlates absent from their native system. The current study examines and compares five language groups’ perception of two synthesized Mandarin tones: the high level tone and the high falling tone. It aims to examine how listeners from tonal and non-tonal backgrounds identify and categorize acoustically equidistant pitches varying along two phonetic dimensions: pitch onset and slope. Results reveal “universal” perceptual patterns across groups and also tendencies caused by native tonal systems. Our findings confirm that L1 tonal and prosodic systems affect speakers’ sensitivity to novel perceptual cues and their abilities to discern relevant phonetic differences.     

The adaptability of self-action perception and movement control when the limb is passively versus actively moved

Research suggests that perceptual experience of our movements adapts together with movement control when we are the agents of our actions. Is this agency critical for perceptual and motor adaptation? We had participants view cursor feedback during elbow extension–flexion movements when they (1) actively moved their arm, or (2) had their arm passively moved. We probed adaptation of movement perception by having participants report the reversal point of their unseen movement. We probed adaptation of movement control by having them aim to a target. Perception and control of active movement were influenced by both types of exposure, although adaptation was stronger following active exposure. Furthermore, both types of exposure led to a change in the perception of passive movements. Our findings support the notion that perception and control adapt together, and they suggest that some adaptation is due to recalibrated proprioception that arises independently of active engagement with the environment.     

A little bit louder now: negative affect increases perceived loudness

Traditionally, perception was considered to be an encapsulated process that was unaffected by top-down processes like affect. Recent work in vision draws this framework into question by showing that changes in the affective state of the perceiver can impact many different aspects of visual perception. Here, we extend the relationship between affect and perception into another perceptual modality: audition. Participants were induced into a negative or neutral mood by writing about a frightening or neutral experience in their past. They then listened to a series of short, neutral tones (320 and 640 ms) and rated the loudness and duration of the tones. Participants in a negative mood rated the tones as significantly louder, but not longer, than participants in a neutral mood, suggesting that the difference between the groups was perceptual rather than just a response bias. This research shows for the first time that the role of affect in perceptual processes may be more pervasive than previously considered.     

自杀意念高中生的社会信息编码特征

采用两因素混合实验设计, 以日常用词为实验材料, 选取不同自杀意念得分的高中生为被试, 通过三个实验考察自杀意念高中生的社会信息编码特征。研究结果发现:(1)自杀意念高分组被试对出现在消极词位置的探测刺激的反应时显著短于出现在积极词位置的探测刺激的反应时; 自杀意念低分组被试对出现在积极词位置的探测刺激的反应时显著短于出现在消极词位置的探测刺激的反应时。(2)在知觉加工水平上, 自杀意念高分组被试对消极词、积极词及中性词的回忆量之间无显著差异; 自杀意念低分组被试对三类词的回忆量之间也不存在显著差异。(3)在语义加工水平上, 自杀意念高分组被试的消极词回忆量显著高于积极词回忆量; 自杀意念低分组被试的积极词回忆量显著高于消极词回忆量。研究结论如下：高自杀意念高中生存在对消极信息的注意偏向和语义加工偏向, 但不存在知觉加工偏向; 低自杀意念高中生存在对积极信息的注意偏向和语义加工偏向, 但不存在知觉加工偏向。     

Temporal preparation decreases perceptual latency: Evidence from a clock paradigm

A clock paradigm was employed to assess whether temporal preparation decreases the time to detect the onset of a stimulus—that is, perceptual latency. In four experiments participants watched a revolving clock hand while listening to soft or loud target tones under high or low temporal preparation. At the end of each trial, participants reported the clock hand position at the onset of the target tone. The deviation of the reported clock hand position from the actual position indexed perceptual latency. As expected, perceptual latency decreased with target tone intensity. Most importantly, however, greater temporal preparation decreased perceptual latency in all four experiments, especially for soft tones, which supports rather directly the idea that temporal preparation diminishes the duration of perceptual processing.     

When aggressive individuals see the world more accurately: the case of perceptual sensitivity to subtle facial expressions of anger

Previous research has suggested that aggressive individuals exhibit a bias to perceive nonangry expressions as angry. Another line of thinking, however, posits that aggression is a learned response to hostile environments and should be linked to social-cognitive skills suited to such environments. If so, aggressive individuals may exhibit greater perceptual sensitivity to subtle facial cues of anger. Three studies were conducted to test this proposal. In them, participants' ability to discriminate between subtly different intensities of facial anger was tested. Aggressive participants generally displayed greater perceptual sensitivity to subtle cues of facial anger. This pattern could not be explained in terms of response bias and was specific to angry expressions. The results thus support the idea that aggression is associated with social-cognitive skills rather than bias and ineptitude.     

The time windows of the sense of agency

The sense of agency depends on some internal cues that derive from action control, as well as external cues like contextual information and prior information (degree of contingency between an action and is effect). We assessed whether external agency cues are combined with internal agency cues to affect the sense of agency. In two experiments participants performed a movement (button press) that elicited, after a varying delay, an effect (ball appearing on a screen), and reported their sense of agency over the effect (full, partial or no-agency) while internal cues (premotor information) and external cues (contextual and prior information) were manipulated. We assessed the effect of agency cues on the delays at which the sense of agency varied. The delays were increased with premotor signals but were decreased with contextual information. These findings favour a model of integration of internal and external agency cues over time.     

Response bias in judging deceptive movements

Two not mutually exclusive explanations, perceptual and motor expertise, account for the finding that experts outperform novices in recognizing deceptive actions from bodily (kinematic) cues. The aim of the present study was twofold: First, we sought to examine the impact of motor and perceptual expertise on distinguishing deceptive and non-deceptive actions. Second, we tested the hypothesis that differences in perceptual judgments on deceptive movements vs. non-deceptive movements do not necessarily need to be caused by either perceptual or motor expertise differences, but can also be a result of response bias. Skilled handball players (field players and goalkeepers) and novices had to detect whether a penalty-taker shot or faked a shot at the goal. Signal detection theory (SDT) analysis revealed that skilled handball players outperformed novices in discriminating shots from fakes. No differences in perceptual sensitivity were found between the goalkeepers and the field players. However, SDT analysis showed that goalkeepers were significantly biased to judge movements as deceptive, while neither field players nor novices showed this response bias.     

Ocular signatures of proactive versus reactive cognitive control in young adults

During the execution of a cognitive task, the brain maintains contextual information to guide behavior and achieve desired goals. The AX-Continuous Performance Task is used to study proactive versus reactive cognitive control. Young adults tend to behave proactively in standard testing conditions. However, it remains unclear how interindividual variability (e.g., in cognitive and motivational factors) may drive people into more reactive or proactive control under the same task demands. We investigated the use of control strategies in a large population of healthy young adults. We computed the proactive behavioral index and consequently divided participants into proactive, reactive, and intermediate groups. We found that reactive participants were generally slower, presented lower context sensitivity, and larger response variability. Pupillary changes and blink rate index cognitive effort allocation. We measured, concomitantly to the task, the pupil size and frequency of blinks associated with the cue maintenance and response intervals. During the cue period, nonfrequent, nontarget cues led to increased pupil dilation and number of blinks in all participants. During the response interval, we found more errors and increased pupil dilation to the probe when all participants had to overcome a response bias generated by the frequent cue. Only reactive participants showed larger response-related pupil when they had to overcome a response bias related to the frequent probe. Contrary to expectations, groups did not differ in ocular measures in the cue period. In conclusion, interindividual differences in cognitive control between healthy adults can be mapped onto different patterns of effort allocation indexed by the pupil.     

Multidimensional processing of dynamic sounds: more than meets the ear

Strong cross-modal interactions exist between visual and auditory processing. The relative contributions of perceptual versus decision-related processes to such interactions are only beginning to be understood. We used methodological and statistical approaches to control for potential decision-related contributions such as response interference, decisional criterion shift, and strategy selection. Participants were presented with rising-, falling-, and constant-amplitude sounds and were asked to detect change (increase or decrease) in sound amplitude while ignoring an irrelevant visual cue of a disk that grew, shrank, or stayed constant in size. Across two experiments, testing context was manipulated by varying the grouping of visual cues during testing, and cross-modal congruency showed independent perceptual and decision-related effects. Whereas a change in testing context greatly affected criterion shifts, cross-modal effects on perceptual sensitivity remained relatively consistent. In general, participants were more sensitive to increases in sound amplitude and less sensitive to sounds paired with dynamic visual cues. As compared with incongruent visual cues, congruent cues enhanced detection of amplitude decreases, but not increases. These findings suggest that the relative contributions of perceptual and decisional processing and the impacts of these processes on cross-modal interactions can vary significantly depending on asymmetries in within-modal processing, as well as consistencies in cross-modal dynamics.     

The role of aesthetic sensitivity in body dysmorphic disorder

Individuals with a higher aesthetic sensitivity may be more vulnerable to developing body dysmorphic disorder (BDD). Aesthetic sensitivity has 3 components: (a) perceptual, (b) emotional, and (c) evaluative. Individuals with BDD (n = 50) were compared with a control group of individuals with an education or employment in art and design related fields (n = 50) and a control group of individuals without aesthetic training (n = 50). A facial photograph of each participant was manipulated to create a 9-image symmetry continuum. Presented with the continuum on a computer, participants were required to select and rate the image representing their self-actual, self-ideal, idea of perfect, most physically attractive, most pleasure, and most disgust. Control symmetry continua examined the specificity of the disturbance. As predicted, BDD participants displayed no distortion in their perceptual processing but were disturbed in their negative emotional/evaluative processing of their self-image. A significant discrepancy between their self-actual and self-ideal, resulting from an absent self-serving bias in their self-actual (a bias exhibited by controls) appears to be the source of their disturbance. They also overvalued the importance of appearance and self-objectified. These aesthetic evaluations may predispose individuals to BDD and/or maintain the disorder.     

Commanding the direction of passive whole-body rotations facilitates egocentric spatial updating

In conditions of slow passive transport without vision, even tenuous inertial signals from semi-circular canals and the haptic-kinaesthetic system should provide information about changes relative to the environment provided that it is possible to command the direction of the body's movements voluntarily. Without such control, spatial updating should be impaired because incoming signals cannot be compared to the expected sensory consequences provided by voluntary command. Participants were seated in a rotative robot (Robuter) and learnt the positions of five objects in their surroundings. They were then blindfolded and assigned either to the active group (n=7) or to the passive group (n=7). Members of the active group used a joystick to control the direction of rotation of the robot. The acceleration (25 degrees /s2) and plateau velocity (9 degrees /s) were kept constant. The participants of the passive group experienced the same stimuli passively. After the rotations, the participants had to point to the objects whilst blindfolded. Participants in the active group significantly outperformed the participants in the passive group. Thus, even tenuous inertial cues are useful for spatial updating in the absence of vision, provided that such signals are integrated as feedback associated with intended motor command.     

No effects of executive control depletion on prospective memory retrieval processes

Research has suggested that prospective memory retrieval is reliant on executive control processes, and the degree to which these processes are necessary for intention fulfillment is dependent on a host of variables related to the prospective memory task. Based on results suggesting that aspects of the prospective memory task vary in their need for executive control, the current study examined the possibility that executive control depletion from the Stroop task would negatively transfer to prospective memory performance. Depletion of executive control, measured objectively in a Stroop task, did not impair prospective memory performance in either low or high cue-target association conditions. However, participants’ subjective assessments of their own cognitive fatigue correlated significantly with their prospective memory performance, regardless of the association between cues and target responses.     

Unilateral hemispheric activation does not affect free-viewing perceptual asymmetries

Strong leftward perceptual biases have been reported for the selection of the darker of two left/right mirror-reversed luminance gradients under free-viewing conditions. This study investigated the effect of unilateral hemispheric activation on this leftward bias in two groups of dextrals (N = 52 and N = 24). In Experiment 1, activation was manipulated by asking participants to tap with their left or right fingers along their midline. In Experiment 2, participants clenched their left or right hands in their respective hemispaces. Participants selected the stimulus that was darker on the left-hand side 73% of the time. Despite manipulations of activation strength and hemispace, activation had no effect on the asymmetry. If activation was important, the leftward bias should have been enhanced when the left hand/right hemisphere was active and reduced (or reversed) when the right hand/left hemisphere was active. The contribution of left-to-right scanning biases to free-viewing perceptual asymmetries is discussed as an alternative.     

Jitter and size effects on vection are immune to experimental instructions and demands

Both coherent perspective jitter and explicit changing-size cues have been shown to improve the vection induced by radially expanding optic flow. We examined whether these stimulus-based vection advantages could be modified by altering cognitions and/or expectations about both the likelihood of self-motion perception and the purpose of the experiment. In the main experiment, participants were randomly assigned into two groups-one where the cognitive conditions biased participants towards self-motion perception and another where the cognitive conditions biased them towards object-motion perception. Contrary to earlier findings by Lepecq et al (1995 Perception 24 435-449), we found that identical visual displays were less likely to induce vection in 'object-motion-bias' conditions than in 'self-motion bias' conditions. However, significant jitter and size advantages for vection were still found in both cognitive conditions (cognitive bias effects were greatest for non-jittering same-size control displays). The current results suggest that if a sufficiently large vection advantage can be produced when participants are expecting to experience self-motion, it is likely to persist in object-motion-bias conditions.     

定向遗忘的编码加工机制

有目的的遗忘(定向遗忘)需要耗费认知努力吗?有研究发现, 定向遗忘可能是被动衰减的结果, 即F项目(需要遗忘的项目)未获得有效复述是选择性复述了R项目(需要记住的项目)造成的, 这一加工过程不需要认知努力; 但也有研究表明, 定向遗忘过程可能是遗忘线索诱发的对记忆加工的主动抑制, 需要耗费认知努力, 脑认知研究中发现的前额叶ERPs成分为这一机制提供了证据。还有一种观点认为, 定向遗忘编码过程可能同时包含主动抑制与被动衰减, 但是尚不清楚两种加工机制相互作用的方式。为进一步澄清定向遗忘编码阶段的认知机制, 未来研究需要将非认知因素纳入考察, 并关注不同人群的定向遗忘特征, 在此基础上尝试解决理论争议。