Perceptual distortion of intrapersonal and near-personal space sensed by proprioception

It is known that the illusory displacement of a vibrated limb can be transferred to a nonvibrated contacted limb. The purpose of this study was to quantify and compare the transferred illusory displacements occurring in the intrapersonal and near-personal space. In two tasks, 8 male and 8 female blindfolded subjects estimated (1) the height of the left elbow and (2) the height of an external object located at the same height as the left elbow, by the proprioception of the right arm which was Subject to illusory displacement. If the internal representation of the left elbow in one's body schema could provide precise information of its static position independently of the proprioception of the right arm, the perceived displacement of the right arm might be smaller when influenced by proprioceptive information from the static left arm, than when in contrast instead with an object which is not a body part. There was no difference in the estimation of illusory displacement between male and female subjects and between right and left arms. No significant difference was observed between transferred displacements of the left elbow and the object. This means that the perception of limb position sensed by the proprioception of another limb can be distorted as easily as the perception of location of an external object. This suggests that the internal representation of static limb position is not enough to provide the correct information of current limb position in the absence of vision.     

Perceptual complexity,rather than valence or arousal accounts for distracter-induced overproductions of temporal durations

For humans and other species, the ability to estimate the physical passage of time is of fundamental importance for perceptual, cognitive or motor functions. Despite this importance, any subjective estimation of temporal durations not only depends on the temporal dynamics of the to-be-timed stimulus or event, but also can be distorted by non-temporal perceptual, cognitive, and emotional effects. This study aimed to further explore critical stimulus characteristics modulating distracter-induced distortions in human time-reproduction. To this end, we investigated whether subjectively rated distracter dimensions of arousal and valence (related to levels of emotionality), or rather stimulus complexity, as a confounder, produce distortions in participants' reproduction of a previously trained target interval. Accuracy and precision of time-reproduction have been measured in distracter-trials, and compared to timing performance in baseline-trials without any distraction. Results showed temporal overproductions in a magnitude of less than distracter duration only for complex distracters. Most importantly, arousal level and valence of distracters were not accountable for temporal distortions. Within an internal clock framework, our pattern of results can best be interpreted in the context of attention-, rather than arousal-based mechanisms of timing.     

Perceptual projects:A theory of veridicality and distortion in perception

Abstract.— The split between objective and subjective information, characterizing dualistic theories of perception, is argued to have caused contradictions around the problems of veridicality of perception and the attention-attracting power of stimulus properties. The theory of threshold-regulation in categorical perception is criticized and an alternative model is suggested, where the main distinctions are between the "knowing how" and the "knowing that" of perception, between exteriorization and interiorization, and between the perceptual project and the perceptual foundation. It is demonstrated that concepts used in the analysis of dialogical communication are useful in the theory of perception to explain phenomena such as curiosity, boredom, and pathological perception.     

"Perceptual scotomas": a functional account of motion-induced blindness

ABSTRACT— In motion-induced blindness (MIB), salient objects in full view can repeatedly fluctuate into and out of conscious awareness when superimposed onto certain global moving patterns. Here we suggest a new account of this striking phenomenon: Rather than being a failure of visual processing, MIB may be a functional product of the visual system's attempt to separate distal stimuli from artifacts of damage to the visual system itself. When a small object is invariant despite changes that are occurring to a global region of the surrounding visual field, the visual system may discount that stimulus as akin to a scotoma, and may thus expunge it from awareness. We describe three experiments demonstrating new phenomena predicted by this account and discuss how it can also explain several previous results.     

Perceptual processing of natural scenes at rapid rates: Effects of complexity, content, and emotional arousal

During rapid serial visual presentation (RSVP), the perceptual system is confronted with a rapidly changing array of sensory information demanding resolution. At rapid rates of presentation, previous studies have found an early (e.g., 150–280 ms) negativity over occipital sensors that is enhanced when emotional, as compared with neutral, pictures are viewed, suggesting facilitated perception. In the present study, we explored how picture composition and the presence of people in the image affect perceptual processing of pictures of natural scenes. Using RSVP, pictures that differed in perceptual composition (figure–ground or scenes), content (presence of people or not), and emotional content (emotionally arousing or neutral) were presented in a continuous stream for 330 ms each with no intertrial interval. In both subject and picture analyses, all three variables affected the amplitude of occipital negativity, with the greatest enhancement for figure–ground compositions (as compared with scenes), irrespective of content and emotional arousal, supporting an interpretation that ease of perceptual processing is associated with enhanced occipital negativity. Viewing emotional pictures prompted enhanced negativity only for pictures that depicted people, suggesting that specific features of emotionally arousing images are associated with facilitated perceptual processing, rather than all emotional content.     

Perceptual adaptation to non-native speech

This study investigated talker-dependent and talker-independent perceptual adaptation to foreign-accent English. Experiment 1 investigated talker-dependent adaptation by comparing native English listeners' recognition accuracy for Chinese-accented English across single and multiple talker presentation conditions. Results showed that the native listeners adapted to the foreign-accented speech over the course of the single talker presentation condition with some variation in the rate and extent of this adaptation depending on the baseline sentence intelligibility of the foreign-accented talker. Experiment 2 investigated talker-independent perceptual adaptation to Chinese-accented English by exposing native English listeners to Chinese-accented English and then testing their perception of English produced by a novel Chinese-accented talker. Results showed that, if exposed to multiple talkers of Chinese-accented English during training, native English listeners could achieve talker-independent adaptation to Chinese-accented English. Taken together, these findings provide evidence for highly flexible speech perception processes that can adapt to speech that deviates substantially from the pronunciation norms in the native talker community along multiple acoustic-phonetic dimensions.     

Perceptual adaptation to facial asymmetries

Humans and other animals are highly sensitive to deviations from bilateral symmetry and prefer symmetric mates. Fluctuating asymmetries (FAs) are random deviations from perfect symmetry that can result from developmental instability. Human perceptions of facial asymmetry are driven by FAs and insensitive to directional asymmetries (DAs), which have a consistent direction of bias (e.g., left side always larger) across the population and are unrelated to developmental stability. We hypothesized that perceptual adaptation may filter out DAs and provide a proximate mechanism for this perceptual focus on FAs. We created a small population of faces with DAs by applying a unilateral distortion to the same side of each face. After 5 min of adaptation, (new) faces with these DAs looked less asymmetric and the most symmetric-looking distortion shifted toward the adapting asymmetry level. Parallel changes occurred for attractiveness. We suggest that perceptual adaptation may provide the proximate mechanism for an evolutionarily adaptive focus on FAs.     

Perceptual learning for speech

Adult language users have an enormous amount of experience with speech in their native language. As a result, they have very well-developed processes for categorizing the sounds of speech that they hear. Despite this very high level of experience, recent research has shown that listeners are capable of redeveloping their speech categorization to bring it into alignment with new variation in their speech input. This reorganization of phonetic space is a type of perceptual learning, or recalibration, of speech processes. In this article, we review several recent lines of research on perceptual learning for speech.     

Using PPT to account for randomness in perception

According to many theories of decision making, of which signal detection theory is the most prominent, randomness is the main factor responsible for imperfect performance. These theories imply that correcting for attenuation due to randomness should result in perfect scores as long as the participants use nonextreme decision criteria. On the basis of a recent advance termed potential performance theory (Trafimow & Rice, Psychological Review 115:447-462, 2008), we performed auditory and visual detection experiments and corrected the scores for attenuation. Most participants in both experiments tended to perform at a less-than-perfect level, even after their scores were corrected. The findings demonstrate that at least one systematic factor influences detection that is not included in signal detection theory.     

知觉经验与知觉内容

知觉(perception)是指我们通过视觉、听觉、触觉、嗅觉、味觉等感觉器官而获得的对事物以及外部世界的意识感知.知觉经验(perceptual experience)的一个显著的特点是它具有某种现象特征,即知觉者会体验到一种"那究竟像什么(what it is like)"的感觉.例如,一个人会从红色视觉经验中体验到"红色究竟像什么"的意识感受性(qualia).知觉内容(perceptual content)粗略地讲是指通过知觉经验向知觉者所传递的信息.关于知觉问题在哲学上的重要性,我们可以从以下几点来看:在形而上学方面,知觉是我们了解外部物理世界究竟存在什么的主要手段;在认识论方面,研究知觉是研究我们如何达到关于外部物理世界的知识的主要手段;在语言哲学方面,知觉内容是我们的心灵与外部物理世界的关联及互动在语言实践上的体现;在心灵哲学方面,知觉经验中的现象特征与意识及意向性之间存在着深层的内在联系.     

Direct Perceptual Access to Other Minds

It is sometimes claimed that we perceive people’s mental states in their expressive features. This paper clarifies the claim by contrasting two possible readings, depending on whether expression is conceived relationally or non-relationally. A crucial difference between both readings is that only a non-relational conception of expression ensures direct access to other minds. The paper offers an argument for a non-relational conception of expression, and therefore for the view that we directly perceive people’s mental states in their expressive features.     

Perceptual experience in learning to read

A group of 24 children (12 boys and 12 girls) aged 10 yr. was given the Children's Embedded Figures Test and a Reading Ability Test on Comprehension, Accuracy, and Speed. Only the correlation of CEFT and Accuracy scores was statistically significant, while that for CEFT and Comprehension scores fell just short of significance, and that for CEFT and Speed was nonsignificant. Data are discussed in terms of more holistic and more articulated processes in learning to read, respectively, as adopted by more field-dependent and more field-independent subjects.     

Misattribution of arousal and attraction: Effects of salience of explanations for arousal

Based on previous research demonstrating that salience of a plausible cause increases the likelihood of causal attribution (S. E. Taylor & S. T. Fiske, in J. Berkowitz (Ed.), Advances in Experimental Social Psychology (Vol. 11), New York: Academic Press, 1978) it was predicted that salience of plausible causes of arousal would affect romantic attraction. Male subjects were differentially aroused by running in place. Aroused subjects were particularly likely to be attracted to an attractive female confederate if they expected to meet her (high salience of confederate) and if cues associated with the running in place were minimized (low salience of exercise). Though results are consistent with a misatribution of arousal hypothesis, it is suggested that emotion schemata are a potentially more useful explanation.