Object Perception Research Articles

Development of a Two-Finger Haptic Robotic Hand with Novel Stiffness Detection and Impedance Control.

Haptic hands and grippers, designed to enable skillful object manipulation, are pivotal for high-precision interaction with environments. These technologies are particularly vital in fields such as minimally invasive surgery, where they enhance surgical accuracy and tactile feedback: in the development of advanced prosthetic limbs, offering users improved functionality and a more natural sense of touch, and within industrial automation and manufacturing, they contribute to more efficient, safe, and flexible production processes. This paper presents the development of a two-finger robotic hand that employs simple yet precise strategies to manipulate objects without damaging or dropping them. Our innovative approach fused force-sensitive resistor (FSR) sensors with the average current of servomotors to enhance both the speed and accuracy of grasping. Therefore, we aim to create a grasping mechanism that is more dexterous than grippers and less complex than robotic hands. To achieve this goal, we designed a two-finger robotic hand with two degrees of freedom on each finger; an FSR was integrated into each fingertip to enable object categorization and the detection of the initial contact. Subsequently, servomotor currents were monitored continuously to implement impedance control and maintain the grasp of objects in a wide range of stiffness. The proposed hand categorized objects' stiffness upon initial contact and exerted accurate force by fusing FSR and the motor currents. An experimental test was conducted using a Yale-CMU-Berkeley (YCB) object set consisted of a foam ball, an empty soda can, an apple, a glass cup, a plastic cup, and a small milk packet. The robotic hand successfully picked up these objects from a table and sat them down without inflicting any damage or dropping them midway. Our results represent a significant step forward in developing haptic robotic hands with advanced object perception and manipulation capabilities.

How small changes to one eye’s retinal image can transform the perceived shape of a very familiar object

Vision can provide useful cues about the geometric properties of an object, like its size, distance, pose, and shape. But how the brain merges these properties into a complete sensory representation of a three-dimensional object is poorly understood. To address this gap, we investigated a visual illusion in which humans misperceive the shape of an object due to a small change in one eye's retinal image. We first show that this illusion affects percepts of a highly familiar object under completely natural viewing conditions. Specifically, people perceived their own rectangular mobile phone to have a trapezoidal shape. We then investigate the perceptual underpinnings of this illusion by asking people to report both the perceived shape and pose of controlled stimuli. Our results suggest that the shape illusion results from distorted cues to object pose. In addition to yielding insights into object perception, this work informs our understanding of how the brain combines information from multiple visual cues in natural settings. The shape illusion can occur when people wear everyday prescription spectacles; thus, these findings also provide insight into the cue combination challenges that some spectacle wearers experience on a regular basis.

A Comprehensive Exploration of Fidelity Quantification in Computer-Generated Images.

Generating realistic road scenes is crucial for advanced driving systems, particularly for training deep learning methods and validation. Numerous efforts aim to create larger and more realistic synthetic datasets using graphics engines or synthetic-to-real domain adaptation algorithms. In the realm of computer-generated images (CGIs), assessing fidelity is challenging and involves both objective and subjective aspects. Our study adopts a comprehensive conceptual framework to quantify the fidelity of RGB images, unlike existing methods that are predominantly application-specific. This is probably due to the data complexity and huge range of possible situations and conditions encountered. In this paper, a set of distinct metrics assessing the level of fidelity of virtual RGB images is proposed. For quantifying image fidelity, we analyze both local and global perspectives of texture and the high-frequency information in images. Our focus is on the statistical characteristics of realistic and synthetic road datasets, using over 28,000 images from at least 10 datasets. Through a thorough examination, we aim to reveal insights into texture patterns and high-frequency components contributing to the objective perception of data realism in road scenes. This study, exploring image fidelity in both virtual and real conditions, takes the perspective of an embedded camera rather than the human eye. The results of this work, including a pioneering set of objective scores applied to real, virtual, and improved virtual data, offer crucial insights and are an asset for the scientific community in quantifying fidelity levels.

Relentless Melt: visual trends and aesthetics of contemporary visual music films in Hong Kong

In recent years, a growing trend of abstract and experimental animation has emerged in Hong Kong, with an increasing number of works produced over the last two decades, particularly since around 2015. This article examines how Hong Kong artists approach abstract animation, the predominant aesthetic trends, and how these trends relate to or diverge from Western traditions in visual music, following pioneers such as Hans Richter, Viking Eggeling, Oskar Fischinger, Harry Smith and Norman McLaren. Employing content analysis, as used by Emmanouil Kanellos (2018) and textual analysis, this study investigates 95 selected works from the Relentless Melt screening series curated by Max Hattler and organized by the Hong Kong-based society Relentless Melt. By categorizing the data under two separate systems – the ‘What System’ and the ‘Where System’, as suggested by Margaret Livingstone in Vision and Art: The Biology of Seeing (2002) – the analysis encompasses aspects related to the perception or recognition of objects, faces, or other properties under the ‘What System’, and the perception of motion, depth, spatial organization and figure/ground segregation under the ‘Where System’. Unlike pioneering visual music artists who largely abandoned mimetic constructions in their aesthetics, some Hong Kong artists employ various types of representational abstraction. In addition, many do not shy away from expressing concepts or narratives in their hybrid visual music works while retaining fundamental elements, such as audio-visual synchronization. This project represents an initial step towards a more systematic understanding of Hong Kong’s visual music practices, aiming to promote plurality over homogeneity by critically examining the multiple facets of artistic practice in Hong Kong. It is hoped that this study will contribute to international scholarly discourse and establish a trajectory for further exploration.

Социально-психологические предикторы воспринимаемого возраста как прогностического маркера старения и риска смерти

<p style="text-align: justify;"><strong>Objective. </strong>The study of socio-psychological predictors of the perceived age of adults aged 35 to 75 years.<br><strong>Background. </strong>The relevance of the work is determined by the interdisciplinary status of the phenomenon of perceived age (the phenomenon of social cognition and the result of the influence of numerous factors associated with predicting the risk of death) in modern science and the need to determine the influence of socio-psychological factors on the perceived age of a person at the stage of "maturity" and "old age". <br><strong>Study design. </strong>Photographs of perceptual objects previously tested using a block of techniques were shown to perceptual subjects ("evaluators") to assess their age, the arithmetic mean of the estimates corresponded to the perceived age of the study participants. Next, a list of possible predictors was compiled, to which multiple regression analysis (step-by-step method) was applied. <br><strong>Participants. </strong>523 people (207 men and 316 women) aged 35 to 75 years took part in the study as objects of perception; 140 people acted as subjects of perception ("evaluators") in various rounds of presenting photographs to assess the age of objects of perception. The sample was divided into subgroups of "mature" (age 35-59 years, 368 people, 142 men and 226 women, M = 49 years) and "elderly" (age 60-75 years, 155 people, 65 men and 90 women, M = 65 years). <br><strong>Measurements. </strong>The procedure of "Photovideopresentation of appearance" by T.A. Vorontsova; the questionnaire "Self-assessment of age" by T.A. Vorontsova; a set of techniques developed by V.A. Labunskaya for the diagnosis of attitude to one's appearance. <br><strong>Results. </strong>The paper identifies socio-psychological predictors of a person's perceived age at the age stages of "maturity" and "old age": subjective age, the importance of appearance, integral assessment of appearance, assessment of appearance by the mother, the need to look younger than their years, economic status. Regression models were compiled separately on male/female subsamples, as well as adults aged 35-59 and 60-75 years. It was found that the regression model built on the data of elderly study participants (from 60 to 75 years old), which included a combination of predictors "significance of appearance", "satisfaction with appearance" and "planned life expectancy", has the greatest predictive value. It is also shown that the behavioral component of the attitude to one's appearance (the severity of appearance-perfectionism) does not affect the indicator of the difference between chronological and perceived age ("saved years").<br><strong>Conclusions. </strong>The combination of socio-psychological predictors of perceived age varies depending on gender and age stage of life. Universal and gender-specific predictors of perceived age have been identified. The universal predictor, regardless of gender and age stage of life, is the importance of appearance.</p>

Performance on a contour integration task as a function of contour shape in schizophrenia and controls

Contour Integration (CI) is the ability to integrate elemental features into objects and is a basic visual process essential for object perception and recognition, and for functioning in visual environments. It is now well documented that people with schizophrenia (SZ), in addition to having cognitive impairments, also have several visual perceptual deficits, including in CI. Here, we retrospectively characterize the performance of both SZ and neurotypical individuals (NT) on a series of contour shapes, made up of Gabor elements, that varied in terms of closure and curvature. Participants in both groups performed a CI training task that included 7 different families of shapes (Lines, Ellipse, Blobs, Squiggles, Spiral, Circle and Letters) for up to 40 sessions. Two parameters were manipulated in the training task: Orientation Jitter (OJ, i.e., orientation deviations of individual Gabor elements from ideal for each shape) and Inducer Number (IN, i.e., number of Gabor elements defining the shape). Results show that both OJ and IN thresholds significantly differed between the groups, with higher (OJ) and lower (IN) thresholds observed in the controls. Furthermore, we found significant effects as a function of the contour shapes, with differences between groups emerging with contours that were considered more complex, e.g., due to having a higher degree of curvature (Blobs, Spiral, Letters). These data can inform future work that aims to characterize visual integration impairments in schizophrenia.

Perception of Soft Objects in Virtual Environments Under Conflicting Visual and Haptic Cues.

In virtual/augmented/mixed reality (VR/AR/MR) applications, rendering soft virtual objects using a hand-held haptic device is challenging due to the anatomical restrictions of the hand and the ungrounded nature of the design, which affect the selection of actuators and sensors and hence limit the resolution and range of forces displayed by the device. We developed a cable-driven haptic device for rendering the net forces involved in grasping and squeezing 3D virtual compliant (soft) objects being held between the index finger and thumb only. Using the proposed device, we investigate the perception of soft objects in virtual environments. We show that the range of object stiffness that can be effectively conveyed to a user in virtual environments (VEs) can be significantly expanded by controlling the relationship between the visual and haptic cues. We propose that a single variable, named Apparent Stiffness Difference, can predict the pattern of human stiffness perception under manipulated conflict, which can be used for rendering a range of soft objects in VEs larger than what is achievable by a haptic device alone due to its physical limits.

THE EFFORTS TO IMPROVE FINANCIAL PERFORMANCE AND MANAGERIAL PERFORMANCE THROUGH PARTICIPATIVE BUDGETING AND BUDGETARY CONTROL

This study examines how participative budgeting and budget control can improve a company's financial and managerial performance. The research method used is quantitative confirmation with a variance-based approach. Questionnaires were distributed online to respondents involved in the budgeting process in order to collect data and facilitate their objective perception of the variables under study. There were 67 respondents who filled out the questionnaire completely and processed it validly. The data's validity and reliability are confirmed by meeting the necessary criteria for processing, including the loading factor, average variance extracted, composite reliability, and discriminant validity with a heterotrait-monotrait ratio. The study results have shown that adequate budget control and involvement of related parties in making budgets will increase discipline and a good understanding of budgets for managers so that they can significantly improve the company's managerial and financial performance.

THE EFFORTS TO IMPROVE FINANCIAL PERFORMANCE AND MANAGERIAL PERFORMANCE THROUGH PARTICIPATIVE BUDGETING AND BUDGETARY CONTROL

This study examines how participative budgeting and budget control can improve a company's financial and managerial performance. The research method used is quantitative confirmation with a variance-based approach. Questionnaires were distributed online to respondents involved in the budgeting process in order to collect data and facilitate their objective perception of the variables under study. There were 67 respondents who filled out the questionnaire completely and processed it validly. The data's validity and reliability are confirmed by meeting the necessary criteria for processing, including the loading factor, average variance extracted, composite reliability, and discriminant validity with a heterotrait-monotrait ratio. The study results have shown that adequate budget control and involvement of related parties in making budgets will increase discipline and a good understanding of budgets for managers so that they can significantly improve the company's managerial and financial performance.

SAMFlow: Eliminating Any Fragmentation in Optical Flow with Segment Anything Model

Optical Flow Estimation aims to find the 2D dense motion field between two frames. Due to the limitation of model structures and training datasets, existing methods often rely too much on local clues and ignore the integrity of objects, resulting in fragmented motion estimation. Through theoretical analysis, we find the pre-trained large vision models are helpful in optical flow estimation, and we notice that the recently famous Segment Anything Model (SAM) demonstrates a strong ability to segment complete objects, which is suitable for solving the fragmentation problem. We thus propose a solution to embed the frozen SAM image encoder into FlowFormer to enhance object perception. To address the challenge of in-depth utilizing SAM in non-segmentation tasks like optical flow estimation, we propose an Optical Flow Task-Specific Adaption scheme, including a Context Fusion Module to fuse the SAM encoder with the optical flow context encoder, and a Context Adaption Module to adapt the SAM features for optical flow task with Learned Task-Specific Embedding. Our proposed SAMFlow model reaches 0.86/2.10 clean/final EPE and 3.55/12.32 EPE/F1-all on Sintel and KITTI-15 training set, surpassing Flowformer by 8.5%/9.9% and 13.2%/16.3%. Furthermore, our model achieves state-of-the-art performance on the Sintel and KITTI-15 benchmarks, ranking #1 among all two-frame methods on Sintel clean pass.

The etiology, diagnostics, and treatment of the spasm of the near reflex - a narrative review.

Physiological adaptation of the eye to the visual perception of near objects consists of the "near triad": convergence, accommodation, and pupil miosis. Normally, these tend to revert when one stops fixating on a near object. Spasm of the near reflex (SNR) is a pathological phenomenon, which manifests itself by the persistence of the above-mentioned adjustments, which prevents the eye from returning to its relaxed state. In this narrative review, we aim to summarize the etiology, diagnostics, treatment, and prevention of SNR. The literature review was performed by searching online databases. The clinical presentation of SNR is diverse; it presents as isolated accommodative spasm more frequently than impairment of all three components of the near triad. Patients usually present with fluctuations in visual acuity, blurred vision, diplopia, and asthenopia. The etiology is not fully understood. Potential causes include neuroanatomic, organic, and psychogenic disorders. The diagnosis is clinical, based on the constellation of symptoms and assessment of the near triad. The diagnostic golden standard is a cycloplegic examination of refraction, preferably using cyclopentolate hydrochloride (1%, 0.5%, or 0.1% solution). The first-line treatment requires the administration of a cycloplegic drug in combination with plus lenses, flipper lenses, optical fogging, or miotics. For secondary cases, causal treatment should be implemented. Prevention of SNR should be based on eliminating modifiable risk factors. We propose including screening for SNR symptoms in every ophthalmic examination, especially among patients with psychogenic or neural disorders, after brain trauma, or young adults spending much time in front of computer screens.

Doppler detection triggers instantaneous escape behavior in scanning bats

Animals must instantaneously escape from predators for survival, which requires quick detection of approaching threats. Although the neural mechanisms underlying the perception of looming objects have been extensively studied in the visual system, little is known about their auditory counterparts. Echolocating bats use their auditory senses to perceive not only the soundscape, but also the physical environment through active sensing. Although object movement induces both echo delay changes and Doppler shifts, the actual information required to perceive movement has been unclear. Herein, we addressed this question by playing back phantom echoes mimicking an approaching target to horseshoe bats and found that they relied only on Doppler shifts. This suggests that the bats do not perceive object motion in the spatiotemporal dimension (i.e., positional variation), as in vision, but rather take advantage of acoustic sensing by directly detecting velocity, thereby enabling them to respond instantaneously to approaching threats.

The Role of Photographic Documentation in the Process of Conservation of Destroyed Architectural Monuments and Centres of Historic Cities

This article deals with the role of photographic documentation in conservation efforts. Using the example of Islamic sites in Libya, historic inn buildings located in Ukraine and Poland, the centres of Polish historic cities destroyed during World War II, and the monuments of Ukraine destroyed during the period of "militant atheism," World War II, and the ongoing Russian-Ukrainian war, it is proven that often photographic documentation of objects becomes the main source of information about destroyed or damaged objects. The purpose of this paper is to analyse the value of photographic documentation for conservation and preservation efforts. The authors point out that it can also be used for eye-tracking studies of visual perception of conservation objects, both by local communities, i.e., nonprofessionals in the field of architecture, as well as perception by architects and conservators.

Seeking information about waste-to-energy incineration projects: The role of objective knowledge and benefit perceptions in an extended PRISM.

Although waste-to-energy (WtE) incineration projects have boosted the economic effectiveness of the waste management system, locals frequently view them with suspicion, opposition, or even outright rejection because of potential environmental and health risks. In this study, by incorporating two additional variables, namely, objective knowledge and benefit perceptions, the planned risk information seeking model (PRISM) was extended in the context of the WtE incineration project. A total of 1726 respondents were interviewed in person. Results from the structural equation modeling indicated that the extended PRISM achieved excellent fits, suggesting the generalizability of the model in these contexts. Objective knowledge and subjective knowledge have a positive and direct impact on perceived knowledge insufficiency. The impact of benefit and risk perceptions on worry is the opposite, with risk perceptions having a greater direct effect on worry. However, compared with risk perceptions, the direct effect that benefit perceptions have on perceived knowledge insufficiency is stronger. Additionally, perceived knowledge insufficiency partially or completely mediates the relationships between all antecedents, except perceived seeking control, and information-seeking intention. This study suggests that risk managers carefully consider how to establish powerful communication tactics to shape these antecedents when introducing a "not in my backyard" project to the local community.

Retinomorphic Photonic Synapses for Mimicking Ultraviolet Radiation Sensing and Damage Imaging

AbstractPhotonic synapses integrate sensing and processing within a single device, making them promising candidates for emulating the visual perception of a biological retina. Most retinomorphic photonic synapses achieve image pre‐processing by differentially responding to red, green, and blue (RGB). However, the impact of invisible ultraviolet (UV) light on the retina remains insufficiently explored, hindering the perception of the full spectrum by retinomorphic devices. Herein, a photonic synapse is constructed with strong UV absorption of Poly[(9,9‐dioctylfluorenyl‐2,7‐diyl)‐co‐(4,4′‐(N‐(4‐sec‐butylphenyl) diphenylamine)] (TFB) as photosensitive layer. The device exhibits synaptic properties of long‐term memory (LTM) and short‐term memory (STM) at different UV radiation stages. Extracting the electrical conductance of the device under UV radiation generates patterns of different resolutions, facilitating the simulation of retinal damage's impact on object perception. Moreover, an electronic eye system, incorporating the photonic synapse under UV radiation, successfully replicates pupil constriction and eye‐closing behaviors akin to those observed in a real biological eye. This result underscores the authenticity of retinomorphic devices, expending a novel concept for the future development of visuomorphic computing.

Functional coupling between auditory memory and verbal transformations

The ability to parse sound mixtures into coherent auditory objects is fundamental to cognitive functions, such as speech comprehension and language acquisition. Yet, we still lack a clear understanding of how auditory objects are formed. To address this question, we studied a speech-specific case of perceptual multistability, called verbal transformations (VTs), in which a variety of verbal forms is induced by continuous repetition of a physically unchanging word. Here, we investigated the degree to which auditory memory through sensory adaptation influences VTs. Specifically, we hypothesized that when memory persistence is longer, participants are able to retain the current verbal form longer, resulting in sensory adaptation, which in turn, affects auditory perception. Participants performed VT and auditory memory tasks on different days. In the VT task, Japanese participants continuously reported their perception while listening to a Japanese word (2- or 3-mora in length) played repeatedly for 5 min. In the auditory memory task, a different sequence of three morae, e.g., /ka/, /hi/, and /su/, was presented to each ear simultaneously. After some period (0–4 s), participants were visually cued to recall one of the sequences, i.e., in the left or right ear. We found that delayed recall accuracy was negatively correlated with the number of VTs, particularly under 2-mora conditions. This suggests that memory persistence is important for formation and selection of perceptual objects.

Assessing Subjective and Objective Road Environment Perception in the Bangkok Metropolitan Region, Thailand: A Deep Learning Approach Utilizing Street Images

Recently, deep learning techniques, specifically semantic segmentation, have been employed to extract visual features from street images, a dimension that has received limited attention in the investigation of the connection between subjective and objective road environment perception. This study is dedicated to exploring and comprehending the factors influencing commuters’ perceptions of the road environment, with the aim of bridging the gap in interpreting environmental quality in Thailand. Semantic segmentation was applied to identify visual objects, expressed as a percentage of pixels represented in 14,812 street images from the Bangkok Metropolitan Region. Subjective road environment perception was assessed through a questionnaire, with a total of 3600 samples collected. Both sets of data were converted to average values per grid, with a grid size of 500 × 500 square meters, resulting in a total of 631 grids with data points. Finally, a multiple linear regression model was employed to analyze the relationship between the ratios of objects obtained from street images via semantic segmentation and human sensory perception of the road environment. The findings from this analysis indicate that the attributes of distinct object classes have a notable impact on individuals’ perceptions of the road environment. Visual elements such as infrastructure, construction, nature, and vehicles were identified as influential factors in shaping the perception of the road environment. However, human and object features did not exhibit statistical significance in this regard. Furthermore, when examining different road environments, which can be categorized into urban, community, and rural contexts, it becomes evident that these contexts distinctly affect the perceptions of various road environments. Consequently, gaining a comprehensive understanding of how street environments are perceived is crucial for the design and planning of neighborhoods and urban communities, facilitating the creation of safer and more enjoyable living environments.

Tax Amnesties: Trends and Implication for Taxpayers’ Compliance. A Literature Review

The focus of this paper is to conduct a literature review on tax amnesties and the factors which are necessary for its effective implementation for compliance. The study employed a library based research design which involves desk-review of extant literature. The literature review shows much research attention given to the issue, though the findings are mixed and quite inconclusive. The review also brings up a few issues which are seen as probable weaknesses or inconsistencies in tax amnesty research looking from a tax compliance perspective. First, while there is evidence regarding success of tax amnesties in the developed world, empirical proof on the progress made in developing countries are scarce. Second, although the concept of tax amnesty has been extensively examined in the tax literature, only a few studies have used an experimental approach to examine the long run effect of tax amnesty on voluntary tax compliance. Third, there is still no clear unanimity in the literature regarding how social and psychological factors such as political trust, political will, perceived corruption, and perceptions of justice and punishment objectives influence the implementation of tax amnesties. Finally, the study observes that in tax amnesty research there is always the tendency for majority of prior studies to assume homogeneity in level of compliance whereas significant differences may exist in the degree of compliance between high and low income earners. The study therefore concludes that there is the need for future empirical studies to address these weaknesses and inconsistencies.

Pilot study of the dynamics of emotional state and quality of life of patients in stage 2 of medical rehabilitation after acute COVID-19

The COVID-19 pandemic has had an enormous impact on public health and many other social institutions. Although the disease continues evolving, new strains do not exhibit the previous lethality, and coronavirus limitations are being lifted, the problem is still relevant. An important aspect of the study of COVID-19 is the process of patient recovery, including inpatient rehabilitation programs. The aim of this pilot study was to examine the psychosocial characteristics and dynamics of the indicators of emotional state (anxiety, depression) and quality of life in patients undergoing a medical rehabilitation program after COVID-19 (N=36; mean age 63.72±12.78 years; 33.33% male, 66.67% female). Research methods included a structured interview to collect data on patients’ sociodemographic and psychosocial characteristics, the State-Trait Anxiety Inventory (STAI), the Beck’s Depression Inventory (BDI), and the 36-Item Short Health Survey (SF-36). The patients were found to have an objective perception of their physical condition, with a lack of awareness of both the disease and the rehabilitation; the illness and recovery situation was markedly stressful for the patients. During the in-patient rehabilitation period, there was a positive change in state anxiety, depressive symptoms and quality of life (p<0.001). The dynamics of the specified characteristics almost do not differ in groups of male and female patients, except for indicators of anxiety, in which differences before and after rehabilitation are more expressed among women. The findings can be used to assess the effectiveness of rehabilitation programs and to improve it, and also indicate the primary role of the clinical psychologist in managing this group of patients.

Language uncovers visuospatial dysfunction in posterior cortical atrophy: a natural language processing approach.

Posterior Cortical Atrophy (PCA) is a syndrome characterized by a progressive decline in higher-order visuospatial processing, leading to symptoms such as space perception deficit, simultanagnosia, and object perception impairment. While PCA is primarily known for its impact on visuospatial abilities, recent studies have documented language abnormalities in PCA patients. This study aims to delineate the nature and origin of language impairments in PCA, hypothesizing that language deficits reflect the visuospatial processing impairments of the disease. We compared the language samples of 25 patients with PCA with age-matched cognitively normal (CN) individuals across two distinct tasks: a visually-dependent picture description and a visually-independent job description task. We extracted word frequency, word utterance latency, and spatial relational words for this comparison. We then conducted an in-depth analysis of the language used in the picture description task to identify specific linguistic indicators that reflect the visuospatial processing deficits of PCA. Patients with PCA showed significant language deficits in the visually-dependent task, characterized by higher word frequency, prolonged utterance latency, and fewer spatial relational words, but not in the visually-independent task. An in-depth analysis of the picture description task further showed that PCA patients struggled to identify certain visual elements as well as the overall theme of the picture. A predictive model based on these language features distinguished PCA patients from CN individuals with high classification accuracy. The findings indicate that language is a sensitive behavioral construct to detect visuospatial processing abnormalities of PCA. These insights offer theoretical and clinical avenues for understanding and managing PCA, underscoring language as a crucial marker for the visuospatial deficits of this atypical variant of Alzheimer's disease.