Perceptual Research Articles

Unity of Body and World in Perceptual Experience in the Phenomenology of Perception

Ponty’nin beden felsefesi, empirizm ve idealizmin beden, bilinç, dünya ve bunlar arasındaki ilişkiye yönelik düşüncesine bir alternatif sunar. Ponty geleneksel metafiziğin düalist ve mekanik beden anlayışlarını yapısöküme uğratarak, kendi fenomenolojik yaşam bedeni düşüncesini geliştirir ve birbirine zıt ama aynı zamanda birbirini zorunlu olarak içeren bu düalist yapıyı, algısal deneyimde beden-özne anlayışıyla aşmaya çalışır. Bedenin dünyayla etkileşimi, zihinsel durumları ve edimleri oluşturduğu için, bilinç kendi çevresinden ayrı düşünülemez. Ponty’de beden, salt bir nesne değil, bir öznedir, bir bilinç formudur. Bu anlamda bedensel bilinç, tüm zihinsel durumlar ve edimlerin dayanağına dönüşür. Ponty bedensel bilince dayalı öznellik anlayışını, algı ve eyleme ilişkin derinlikli araştırmasıyla ortaya koymaya çalışır. Beden, ne dünya içinde diğer nesneler gibi bir nesnedir ne de bilinçten bağımsız bir varoluşa sahiptir. Ponty’de birey, kendinin bedenidir. Beden-öznenin bedensel varoluşu onun dünyaya yönelimsel açılımını olanaklı kılar. Bu açıdan Ponty’nin Algının Fenomenolojisi’nde betimlediği beden felsefesi aslında bireysel varoluşa ilişkin bir sorgulamadır. Algısal, bedensel bir düzeyde, düşünüme öncel bir varoluş durumunda bilinç ve dünyanın karşılıklı ilksel etkileşimi, belirsiz mevcudiyet üzerinde fenomenlerin görünür olmasını ve anlam olanaklarının sınırsız ufkunun açılmasını mümkün kılar. Düşünüme, yargıya ve anlama öncel olan beden ve dünyanın her an yinelenen bu ilksel teması, fenomenal alanı açan yaratıcı bir eylemselliktir. Bu makalenin amacı Ponty’nin kendi beden analizinde insan varoluşunun dünyadalığını ve algıda kendini beden olarak duyumsayan bireyin yönelimselliğini hareket, motor beceri, alışkanlık, cinsellik ve beden-şema kavramları aracılığıyla nasıl açımladığını ve böylece insani varoluşun olanağını, dünyayla düşünüm-öncesi etkileşime nasıl dayandırdığını açıklamaktır. Bu bedensel varoluş tarzı, algının ve dünyanın belirsiz ufkunda, birbiriyle bağlantılı sınırsız ilişkiler ağını açar ve her türden nesnel hakikat iddialarını geçersiz kılar.

A method for multi-person mobile virtual reality fire evacuation drills based on pose estimation: Consistency of vision and perception

Fire disasters present significant risks, emphasizing the need for effective evacuation drills. Traditional drills in real environments have limitations such as safety risks and poor repeatability. Immersive Virtual Reality (iVR) provides a safer, more engaging alternative, but early iVR-based drills were restricted due to hardware limitations. The advent of mobile virtual reality has overcome some of these restrictions. However, challenges remain in multi-person evacuation scenarios, such as difficulties in relative positioning and the real time interaction of evacuees. This study addresses these issues using pose estimation for accurate positioning in virtual reality devices. Furthermore, we developed a framework for conducting evacuation drills in a real environment using mobile virtual reality, ensuring consistency in participants' visual and perceptual experiences. Subsequently, we designed two experiments to validate this methodology and framework. The experimental results demonstrated that the evacuation process, using pose estimation, effectively eliminates cumulative error, maintaining an approximate error of 0.04 m between the real and virtual environments. Participants also reported having a better experience and found it easier to interact with others during the mobile virtual reality evacuation.

Does report modality modulate psychophysical sensitivity? The jury remains out

Scientific studies of perception use motoric reports as the principal means of communicating subjective experience. In such experiments, a widely held and implicit assumption is that the motor action conveys but does not tamper with perceptual experience. We tested nine observers on a luminance detection task in a cross-over repeated measures design. In separate conditions, observers reported their detection via movements of either their hands or eyes. We found only anecdotal evidence for any modality-dependent effect on psychophysical sensitivity. We also reanalyzed an existing dataset from which deployed a similar detection paradigm involving hand and eye reports. In the four paradigm variants tested, we again only found anecdotal evidence for the effect of report modality on psychophysical sensitivity. Both studies reported here provide only anecdotal evidence; thus, whether we can replicate report-dependent perceptual effects still needs to be resolved. We argue why this remains an important question for consciousness research and why it deserves more rigorous and high-powered replication attempts.

Investigating the Role of Leading Sensory Modality and Autistic Traits in the Visual-Tactile Temporal Binding Window.

Our ability to integrate multisensory information depends on processes occurring during the temporal binding window. There is limited research investigating the temporal binding window for visual-tactile integration and its relationship with autistic traits, sensory sensitivity, and unusual sensory experiences. We measured the temporal binding window for visual-tactile integration in 27 neurotypical participants who completed a simultaneity judgement task and three questionnaires: the Autism Quotient, the Glasgow Sensory Questionnaire, and the Multi-Modality Unusual Sensory Experiences Questionnaire. The average width of the visual-leading visual-tactile (VT) temporal binding window was 123ms, significantly narrower than the tactile-leading visual-tactile (TV) window (193ms). When comparing crossmodal (visual-tactile) stimuli with unimodal (visual-visual or tactile-tactile), the temporal binding window was significantly larger for crossmodal stimuli (VT: 123ms; TV: 193ms) than for unimodal pairs of stimuli (visual: 38ms; tactile 42ms). We did not find evidence to support a relationship between the size of the temporal binding window and autistic traits, sensory sensitivities, or unusual sensory perceptual experiences in this neurotypical population. Our results indicate that the leading sense presented in a multisensory pair influences the width of the temporal binding window. When tactile stimuli precede visual stimuli it may be difficult to determine the temporal boundaries of the stimuli, which leads to a delay in shifting attention from tactile to visual stimuli. This ambiguity in determining temporal boundaries of stimuli likely influences our ability to decide on whether stimuli are simultaneous or nonsimultaneous, which in turn leads to wider temporal binding windows.

Phenomenology, Quantity, and Numerosity.

There are many situations in which we interact with collections of objects, from a crowd of people to a bowl of blackberries. There is an experience of the quantity of these items, although not a precise number, and we have this impression quickly and effortlessly. It can be described as an expressive property of the whole. In the literature, the study of this sense of numerosity has a long history, which is reviewed here with examples. I argue that numerosity is a direct perceptual experience, and that all experiences of numerosity, not only estimations, are affected by perceptual organisation.

Sensory translation between audition and vision.

Across the millennia, and across a range of disciplines, there has been a widespread desire to connect, or translate between, the senses in a manner that is meaningful, rather than arbitrary. Early examples were often inspired by the vivid, yet mostly idiosyncratic, crossmodal matches expressed by synaesthetes, often exploited for aesthetic purposes by writers, artists, and composers. A separate approach comes from those academic commentators who have attempted to translate between structurally similar dimensions of perceptual experience (such as pitch and colour). However, neither approach has succeeded in delivering consensually agreed crossmodal matches. As such, an alternative approach to sensory translation is needed. In this narrative historical review, focusing on the translation between audition and vision, we attempt to shed light on the topic by addressing the following three questions: (1) How is the topic of sensory translation related to synaesthesia, multisensory integration, and crossmodal associations? (2) Are there common processing mechanisms across the senses that can help to guarantee the success of sensory translation, or, rather, is mapping among the senses mediated by allegedly universal (e.g., amodal) stimulus dimensions? (3) Is the term 'translation' in the context of cross-sensory mappings used metaphorically or literally? Given the general mechanisms and concepts discussed throughout the review, the answers we come to regarding the nature of audio-visual translation are likely to apply to the translation between other perhaps less-frequently studied modality pairings as well.

Perceptual discrimination in the face perception of robots is attenuated compared to humans

When interacting with groups of robots, we tend to perceive them as a homogenous group where all group members have similar capabilities. This overgeneralization of capabilities is potentially due to a lack of perceptual experience with robots or a lack of motivation to see them as individuals (i.e., individuation). This can undermine trust and performance in human–robot teams. One way to overcome this issue is by designing robots that can be individuated such that each team member can be provided tasks based on its actual skills. In two experiments, we examine if humans can effectively individuate robots: Experiment 1 (n = 225) investigates how individuation performance of robot stimuli compares to that of human stimuli that either belong to a social ingroup or outgroup. Experiment 2 (n = 177) examines to what extent robots’ physical human-likeness (high versus low) affects individuation performance. Results show that although humans are able to individuate robots, they seem to individuate them to a lesser extent than both ingroup and outgroup human stimuli (Experiment 1). Furthermore, robots that are physically more humanlike are initially individuated better compared to robots that are physically less humanlike; this effect, however, diminishes over the course of the experiment, suggesting that the individuation of robots can be learned quite quickly (Experiment 2). Whether differences in individuation performance with robot versus human stimuli is primarily due to a reduced perceptual experience with robot stimuli or due to motivational aspects (i.e., robots as potential social outgroup) should be examined in future studies.

Subjective and objective measures of visual awareness converge.

Within consciousness research, the most appropriate assessment of visual awareness is matter of a controversial debate: Subjective measures rely on introspections of the observer related to perceptual experiences, whereas objective measures are based on performance of the observer to accurately detect or discriminate the stimulus in question across a series of trials. In the present study, we compared subjective and objective awareness measurements across different stimulus feature and contrast levels using a temporal two-alternative forced choice task. This task has the advantage to provide an objective psychophysical performance measurement, while minimizing biases from unconscious processing. Thresholds based on subjective ratings with the Perceptual Awareness Scale (PAS) and on performance accuracy were determined for detection (stimulus presence) and discrimination (letter case) tasks at high and low stimulus contrast. We found a comparable pattern of thresholds across tasks and contrasts for objective and subjective measurements of awareness. These findings suggest that objective performance measures based on accuracy and subjective ratings of the visual experience can provide similar information on the feature-content of a percept. The observed similarity of thresholds validates psychophysical and subjective approaches to awareness as providing converging and thus most likely veridical measures of awareness.

Interpersonal prior information informs ensemble coding through the co-representation process.

Humans have the ability to rapidly extract summary statistics from object groupings through a specific capability known as ensemble coding. Previous literature has reported that this ability can become biased by prior perceptual experiences at the individual level. However, it remains unknown whether interpersonal prior information could also bias ensemble perception through a co-representation process. Experiment 1 found that participants' summary estimations were biased toward their co-actor's stimuli. Experiment 2 confirmed a causal relationship between the bias effect and the co-representation process by showing a reduction in biased estimation after pairing participants with an out-group partner. These findings extend the sources of prior information exploited by humans during perceptual average from individual-level information (i.e., self-tasks) to interpersonal-level information (i.e., co-actor's tasks). More specifically, interpersonal prior information is shown to act in a top-down and implicit manner, biasing ensemble perception.

Serial Dependence in Perception.

Much evidence has shown that perception is biased towards previously presented similar stimuli, an effect recently termed serial dependence. Serial dependence affects nearly every aspect of perception, often causing gross perceptual distortions, especially for weak and ambiguous stimuli. Despite unwanted side-effects, empirical evidence and Bayesian modeling show that serial dependence acts to improve efficiency and is generally beneficial to the system. Consistent with models of predictive coding, the Bayesian priors of serial dependence are generated at high levels of cortical analysis, incorporating much perceptual experience, but feed back to lower sensory areas. These feedback loops may drive oscillations in the alpha range, linked strongly with serial dependence. The discovery of top-down predictive perceptual processes is not new, but the new, more quantitative approach characterizing serial dependence promises to lead to a deeper understanding of predictive perceptual processes and their underlying neural mechanisms.

Grounding Intuitive Physics in Perceptual Experience.

This review article explores the foundation of laypeople's understanding of the physical world rooted in perceptual experience. Beginning with a concise historical overview of the study of intuitive physics, the article presents the hypothesis that laypeople possess accurate internalized representations of physical laws. A key aspect of this hypothesis is the contention that correct representations of physical laws emerge in ecological experimental conditions, where the scenario being examined resembles everyday life experiences. The article critically examines empirical evidence both supporting and challenging this claim, revealing that despite everyday-life-like conditions, fundamental misconceptions often persist. Many of these misconceptions can be attributed to a domain-general heuristic that arises from the overgeneralization of perceptual-motor experiences with physical objects. To conclude, the article delves into ongoing controversies and highlights promising future avenues in the field of intuitive physics, including action-judgment dissociations, insights from developmental psychology, and computational models integrating artificial intelligence.

Self as a prior: The malleability of Bayesian multisensory integration to social salience.

Our everyday perceptual experiences are grounded in the integration of information within and across our senses. Due to this direct behavioural relevance, cross-modal integration retains a certain degree of contextual flexibility, even to social relevance. However, how social relevance modulates cross-modal integration remains unclear. To investigate possible mechanisms, Experiment 1 tested the principles of audio-visual integration for numerosity estimation by deriving a Bayesian optimal observer model with perceptual prior from empirical data to explain perceptual biases. Such perceptual priors may shift towards locations of high salience in the stimulus space. Our results showed that the tendency to over- or underestimate numerosity, expressed in the frequency and strength of fission and fusion illusions, depended on the actual event numerosity. Experiment 2 replicated the effects of social relevance on multisensory integration from Scheller & Sui, 2022 JEP:HPP, using a lower number of events, thereby favouring the opposite illusion through enhanced influences of the prior. In line with the idea that the self acts like a prior, the more frequently observed illusion (more malleable to prior influences) was modulated by self-relevance. Our findings suggest that the self can influence perception by acting like a prior in cue integration, biasing perceptual estimates towards areas of high self-relevance.

Expectation Cues and False Percepts Generate Stimulus-Specific Activity in Distinct Layers of the Early Visual Cortex.

Perception has been proposed to result from the integration of feedforward sensory signals with internally generated feedback signals. Feedback signals are believed to play an important role in driving false percepts, that is, seeing things that are not actually there. Feedforward and feedback influences on perception can be studied using layer-specific fMRI, which we used here to interrogate neural activity underlying high-confidence false percepts while healthy human participants (N = 25, male and female) performed a perceptual orientation discrimination task. Auditory cues implicitly signaled the most likely upcoming orientation (referred to here as expectations). These expectations induced orientation-specific templates in the deep and superficial layers of V2, without affecting perception. In contrast, the orientation of falsely perceived stimuli with high confidence was reflected in the middle input layers of V2, suggesting a feedforward signal contributing to false percepts. The prevalence of high-confidence false percepts was related to everyday hallucination severity in a separate online sample (N = 100), suggesting a possible link with abnormal perceptual experiences. These results reveal a potential feedforward mechanism underlying false percepts, reflected by spontaneous stimulus-like activity in the input layers of the visual cortex, independent of top-down signals reflecting cued orientations.SIGNIFICANCE STATEMENT False percepts have been suggested to arise through excessive feedback signals. However, feedforward contributions to false percepts have remained largely understudied. Laminar fMRI has been shown to be useful in distinguishing feedforward from feedback activity as it allows the imaging of different cortical layers. In the present study we demonstrate that although cued orientations are encoded in the feedback layers of the visual cortex, the content of the false percepts are encoded in the feedforward layers and did not rely on these cued orientations. This shows that false percepts can in principle emerge from random feedforward signals in the visual cortex, with possible implications for disorders hallmarked by hallucinations like schizophrenia and Parkinson's disease.

Effects of interocular grouping demands on binocular rivalry.

Binocular rivalry (BR) is a visual phenomenon in which perception alternates between two non-fusible images presented to each eye. Transition periods between dominant and suppressed images are marked by mixed percepts, where participants report fragments of each image being dynamically perceived. Interestingly, BR remains robust even when typical images are subdivided and presented in complementary patches to each eye, a phenomenon termed interocular grouping (IOG). The objective of the present study was to determine if increasing grouping demand in the context of BR changes the perceptual experience of rivalry. In 48 subjects with normal vision, mean dominant and mixed percept durations were recorded for classic BR and IOG conditions with increasing grouping demands from two, four, and six patches. We found that, as grouping demands increased, the duration of mixed periods increased. Indeed, durations of dominant and mixed percepts, as well as percentage of time spent in dominant or mixed state, differed significantly across conditions. However, durations of global dominant percepts remained relatively stable and saturated at about 1.5 seconds, despite the exponential increase in possible mixed combinations. Evidence shows that this saturation followed a nonlinear trend. The data also indicate that grouping across the vertical meridian is slightly more stable than for the horizontal meridian. Finally, individual differences in speed of alternation identified during BR were maintained in all interocular grouping conditions. These results provide new information about binocular visual spatial integration and will be useful for future studies of the underlying neural substrates and models of binocular vision.

Perception, force, and content

AbstractPerceptual experiences have presentational phenomenology: we seem to encounter real situations in the course of visual experiences, for instance. The current paper articulates and defends the claim that the contents of at least some perceptual experiences are inherently presentational. On this view, perceptual contents are not always forceless in the way that, say, the propositional content that 2 + 2 = 4 is generally taken to be, as a content that may be asserted or denied or merely supposed; rather, there are perceptual contents such that any mental state or episode which has the relevant content must be one in which things seem to the given subject to be a certain way. Intuitive motivation for the view is presented and an explanatory line of argument in support of it is developed: it is argued that the recognition of inherently presentational perceptual contents allows us to explain certain representational limitations to which ordinary visualizations and other forms of perceptual mental imagery are subject. Some potential objections to the position are explored, leading to further elaboration of it.

The role of imagination and recollection in the method of phenomenal contrast

AbstractThe method of phenomenal contrast (in perception) invokes the phenomenal character of perceptual experience as a means to discover its contents. The method implicitly takes for granted that ‘what it is like’ to have a perceptual experience e is the same as ‘what it is like’ to imagine or recall it; accordingly, in its various proposed implementations, the method treats imaginations and/or recollections as interchangeable with real experiences. The method thus always contrasts a pair of experiences, at least one of which is imagined or remembered rather than occurrent. Surveying all eighteen forms of implementing the method, I argue that in all of the proposed pairings, the substitution of imagination or recollection for perceptual experience in the method, is either inconceivable or impermissible. I identify four reasons why I think imagination cannot be substituted for real experience, and three reasons why recollection cannot be substituted for real experience. If my argument works, there is no form of implementing the method that is useful for discovering the contents of experience, and thus the method is not a well‐functioning tool to study the contents of perception.

Perception and Disjunctive Belief: A New Problem for Ambitious Predictive Processing

ABSTRACT Perception can’t have disjunctive content. Whereas you can think that a box is blue or red, you can’t see a box as being blue or red. Based on this fact, I develop a new problem for the ambitious predictive processing theory, on which the brain is a machine for minimizing prediction error, which approximately implements Bayesian inference. I describe a simple case of updating a disjunctive belief given perceptual experience of one of the disjuncts, in which Bayesian inference and predictive coding pull in opposite directions, with the former implying that one’s confidence in the belief should increase, and the latter implying that it should decrease. Thus, predictive coding fails to approximately implement Bayesian inference across the interface between belief and perception.

The effect of emotion type and similarity of experience on consumers' willingness to pay for cause‐related products: Construal level perspective

AbstractInformation complexity hinders consumer processing and reduces positive responses to cause‐related products. Previous studies on cause‐related marketing (CRM) have focused more on messaging effects on reducing information complexity, such as the presentation of the donation amount, cause description, and image displays. This study discusses the effect of construal fit on consumers' willingness to pay (WTP) for products sold through CRM by focusing on the emotional and perceptual aspects of prior experiences. Notably, sadness has a low‐level construal fit with a high similarity of experience, whereas happiness has a high‐level construal fit with a low similarity of experience. Study 1 employs a between‐subjects design, examining how the construal fit influences WTP for cause‐related products. The results of Study 2 reveal that when consumers are in a sad (happy) emotional state, the higher (lower) they perceive the similarity of their experiences with the cause, the greater their WTP increases owing to processing fluency. Study 3 reconfirms the mediating roles of perceptual and conceptual fluency irrespective of text‐based and visual advertisements for CRM, thus showing the robustness of the construal fit effect on the enhancement of the two types of processing fluency across advertising contexts. These findings contribute to the theoretical understanding of the construal fit between emotional and perceptual experiences in enhancing processing fluency in CRM and suggest that marketers can create a teaser ad that induces either a sad or similar experience or a happy or less similar experience before introducing a CRM campaign.

Acoustic features drive event segmentation in speech.

While our perceptual experience seems to unfold continuously over time, episodic memory preserves distinct events for storage and recollection. Previous work shows that stability in encoding context serves to temporally bind individual items into sequential composite events. This phenomenon has been almost exclusively studied using visual and spatial memory paradigms. Here we adapt these paradigms to test the role of speaker regularity for event segmentation of complex auditory information. The results of our auditory paradigm replicate the findings in other sensory modalities-finding greater within-event temporal memory for items within speaker-bound events and greater source memory for items at speaker or event transitions. The task we use significantly extends the ecological validity of past paradigms by allowing participants to encode the stimuli without any suggestions on the part of the experimenter. This unique property of our design reveals that, while memory performance is strongly dependent on self-reported mnemonic strategy, behavioral effects associated with event segmentation are robust to changes in mnemonic strategy. Finally, we consider the effect of serial position on segmentation effects during encoding and present a modeling approach to estimate the independent contribution of event segmentation. These findings provide several lines of evidence suggesting that contextual stability in perceptual features drives segmentation during word listening and supports a modality-independent role for mechanisms involved in event segmentation. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The epistemic insignificance of phenomenal force

AbstractDoes phenomenal force, the distinctive phenomenology attributed to perceptual experience, really form an integral part of the latter? If not, what implications does it have for perceptual justification? In this paper, I first argue for a metacognitive account, according to which phenomenal force constitutes a separate, metacognitive state. This account opens up a previously unexplored path for challenging phenomenal conservatism or dogmatism, which has been a prominent theory of perceptual justification over the past two decades. Moreover, I investigate several alternative possibilities in which phenomenal force might still be deemed as significant, but ultimately demonstrate that its epistemic role remains marginal at best.