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The brain strives to become a model of the world in which it must survive. It is often more important for it to be functional and efficient than it is to be factually correct. Indeed, there are numerous instances in which it seems to favour usefulness over accuracy, expectation over actuality. This has led many to conclude that even normal perception has a constructive or hallucinatory quality. In extremis, under the influence of fatigue, fear, illness or drugs, an entire reality may be created, one that seems to conflict with the reality accepted by those around us. This condition, known as psychosis, offers us important glimpses into the mechanisms of the mind and the many ways in which they may be altered.
Signage design has been considered critically important for wayfinding, being a functional medium of delivering environmental information. Complex institutional environments have several factors affecting the wayfinding, including but not limited to the design of information signage and its visual preference. Visual preferences of information design in wayfinding signage vary, depending on the cultural and individual differences. This study explores the variance in design and visual preferences of wayfinding signage and its influencing elements. Responses through online questionnaire have been accumulated by the participants from Hong Kong and Pakistan based on their design and visual preference of campus wayfinding signage. Questions were asked related to the user preferences for signage colour if in line with the institutional visual identity, mono or multi-colour coding of information and its visual volume. In total, 170 university students and visitors participated in the exploratory study from the respective countries. The results demonstrated that participants of Hong Kong preferred inline colours of signage, along with mono or less colour coding and detailed information. While the other group preferred attractive colours with multi-colour coding and less detailed wayfinding information with pictograms. Individual differences concerning age, literacy level and gender were also computed, however trivial differences have been recorded. This study suggests the need for detailed cross-cultural investigation concerning elements of signage design and visual preference to identify the drivers for culturally consistent university signage.
Visual imagery can be advantageous in much of cognition, unnecessary (aphantasia), to clinically disruptive (PTSD). It allows us to disconnect our senses from reality and test out virtual combinations of sensory experience. With many methodological constraints now overcome, research has shown that visual imagery involves a network of brain areas from frontal cortex to sensory areas and it can function much like a weak version of afferent perception. Imagery vividness and strength range from completely absent (aphantasia) to photo-like (hyperphantasia). Both the anatomy and function of the primary visual cortex are related to visual imagery. The use of imagery as a tool has been linked to a many superordinate compound cognitive processes. Imagery plays both symptomatic and mechanistic roles in neurological and mental disorders, and some of their treatments. Although many unanswered questions remain, we now have multiple objective methods to investigate imagery, and hence shed light not just on imagery, but on the many reliant cognitive processes
Nineteen different slides of food items and their effects on appetite and hunger as rated on visual analogue scales were investigated in 20 bulimics and 9 anorexics (DSM-III-R) at the onset and after 8 weeks of behavioral hospital treatment; 9 controls were examined at the maximum of weight loss during a diet and at normal weight. At the onset of treatment appetite ratings were significantly lower in patients than in dieting controls. In anorexics and bulimics appetite ratings increased significantly during treatment. The sight of food did not increase reported hunger in bulimics but did so in controls. Appetite ratings, however, were significantly increased by the sight of food in bulimics as well as in controls. Despite the small sample size, it may be concluded that dieting and weight loss have different psychological implications in healthy controls and in patients with eating disorders, that dieting rather than weight per se influences appetite and that differences in hunger responsiveness to the sight of food in anorexics and bulimics seem likely.
The Molyneux problem is a question about the nature of sensory perception that was first posed by William Molyneux, the founder of the Dublin Philosophical Society, in correspondence with the English philosopher John Locke in 1688. The problem asks whether a blind man who has learned to distinguish between different shapes by his sense of touch alone would be able, upon having his vision restored, to make the same distinctions using only his sense of sight. Molyneux’s question has been called the most important problem in the history of Irish philosophy, and the reason for its significance is the wide variety of epistemological, theological, linguistic, and aesthetic considerations to which it gave rise. This chapter identifies and documents the major stages in the early development of Molyneux’s problem in eighteenth-century Ireland, England, and France. Along the way, the chapter draws on contemporary religious analogies, surgical evidence, and fictional experiments in order to bring a new perspective to current debates about the meaning of ‘Enlightenment’ in eighteenth-century Irish intellectual culture.
Aging-related changes in visual sensory processing, visual perception, and visuospatial cognition are well documented and contribute to substantial disability in the older adult population. This chapter reviews neuropsychological and neurobiological bases of disorders of face recognition, form perception, object recognition, mental/spatial imagery, spatial memory, and environmental navigation, and discusses how the aging process affects functional brain systems underlying these complex disorders.
This chapter is dedicated to showing the technique used by John to portray himself as an eyewitness: description. This description, in the classical rhetorical tradition of ante oculos ponere, engages the audience in the narrative by giving them the opportunity to visualize what John himself saw. For example, descriptions introduced by the phrase ?a? e?d?? are rendered as though they formed part of a transcription of a vision made at the very moment it occurred. This is why they appear in the text ex abrupto, marked only by the introductory sign ?a? e?d??, a device habitually used to signal the reader/listener that a given vision has occurred unexpectedly. The ?a? e?d?? structure mimics the mechanics of sight. However, the descriptive forms employed in the book of Revelation are not limited to the use of this ?a? e?d?? pattern. On the contrary, throughout the text John employs six other kinds of descriptions: 1) ????sa ?a? e?d?? descriptions, or ecphrasis; 2) e?d??-????? descriptions; 3) t? p???e??µe?a descriptions; 4) ?a? e?d?? ???e??? descriptions; 5) ?? t? d????se? descriptions; 6) t?p?? or t?p???af?a descriptions.
The amount of new virtual reality input and output devices being developed is enormous. Those peripherals offer novel opportunities and possibilities in the industrial context, especially in the product development process. Nevertheless, virtual reality has to face several problems, counteracting reliable use of the technology, especially in ergonomic and aesthetic assessments. In particular, the discrepancies in perception between the real world and virtual reality are of great importance.
Therefore, we discuss these most important issues of current virtual reality technology and highlight approaches to solve them. First, we illustrate the use cases of VR in the product development process. In addition, we show which hardware is currently available for professional use and which issues exist with regard to visual perception and interaction. Derived from the depiction of a perfect virtual reality, we define the requirements to address visual perception and interaction. Subsequently we discuss approaches to solve the issues regarding visual perception and evaluate their suitability to enhance the use of virtual reality technology in engineering design.
Objective: Detection of cognitive impairment suggestive of risk for Alzheimer’s disease (AD) progression is crucial to the prevention of incipient dementia. This study was performed to determine if performance on a novel object discrimination task improved identification of earlier deficits in older adults at risk for AD. Method: In total, 135 participants from the 1Florida Alzheimer’s Disease Research Center [cognitively normal (CN), Pre-mild cognitive impairment (PreMCI), amnestic mild cognitive impairment (aMCI), and dementia] completed a test of object discrimination and traditional memory measures in the context of a larger neuropsychological and clinical evaluation. Results: The Object Recognition and Discrimination Task (ORDT) revealed significant differences between the PreMCI, aMCI, and dementia groups versus CN individuals. Moreover, relative risk of being classified as PreMCI rather than CN increased as an inverse function of ORDT score. Discussion: Overall, the obtained results suggest that a novel object discrimination task improves the detection of very early AD-related cognitive impairment, increasing the window for therapeutic intervention. (JINS, 2019, 25, 688–698)
Hermit crabs use different senses to search for and find shells. In most cases, chemical cues have been proven to act as a very efficient way of finding new shells. However, in intertidal environments, the water transports chemical signals in different directions and velocities may make it harder to track the source of the cue, so visual stimuli may be a more precise source of information. The hermit crab Calcinus californiensis shows a preference for the biconical shells of Stramonita biserialis, although the crabs may also use the less preferred shell of Nerita scabricosta. We were interested in exploring if C. californiensis identify the preferred shell species through vision in the absence of chemical stimuli. We presented both shell species to hermit crabs in two different sets of experiments. In one experiment, we presented to the hermit crabs real shells of N. scabricosta and S. biserialis, and in another, we presented only the silhouettes of the same shells. The hermit crabs discriminated between the real shells and the silhouettes of N. scabricosta and S. biserialis. Females attended with higher frequency to real shells and silhouettes of S. biserialis; while males attended more to shells and silhouettes of N. scabricosta. Although, larger males biased their attendance toward shells of S. biserialis. Our results show that visual perception may be more important than we have thought in intertidal animals.
Validated methodological aids for food quantification are needed for the accurate estimation of food consumption. Our objective was to assess the validity of an age-specific food picture book, which contains commonly eaten foods among Finnish children, for parents and early educators in estimating food portion sizes. The food picture book was developed to assist in portion size estimation when filling in food records in the Increased health and wellbeing in preschools (DAGIS) study. All ninety-five food pictures in the book, each containing three or four different portion sizes, were evaluated at real-time sessions. Altogether, seventy-three parents and 107 early educators or early education students participated. Each participant evaluated twenty-three or twenty-four portions by comparing presented pre-weighed food portions against the corresponding picture from the food picture book. Food portions were not consumed by participants. The total proportion of correct estimations varied from 36 % (cottage cheese) to 100 % (fish fingers). Among the food groups, nearly or over 90 % of the estimations were correct for bread, pastries and main courses (‘piece products’ such as meatballs and chicken nuggets). Soups, porridges, salads and grated and fresh vegetables were least correctly estimated (<65 % correct estimations). There were small differences in evaluations of berries and fresh fruits, warm vegetables and pastries between the parents and early educators, but other estimations were mostly similar. The children's food picture book was found to be a useful aid for the estimation of food portion sizes. Parents and early educators evaluated the portion sizes with similar accuracy.
Objectives: Body dysmorphic disorder (BDD) is characterized by repetitive behaviors and/or mental acts occurring in response to preoccupations with perceived defects or flaws in physical appearance. There are some similarities, but also important differences, between BDD and obsessive-compulsive disorder (OCD), not just in terms of core clinical symptoms, but possibly in the domain of perception. This study compared the nature and extent of perceptual anomalies in BDD versus OCD and health controls (HC), using a modified Mooney task. Methods: We included 21 BDD, 19 OCD, and 21 HC participants, who were age-, sex-, and IQ-matched. A set of 40 Mooney faces and 40 Mooney objects arranged in three configurations (i.e., upright, inverted, or scrambled) were presented under brief (i.e., 500 ms) free-viewing conditions. Participants were asked to decide whether each image represented a human face, an object, or neither in a forced-choice paradigm. Results: The BDD group showed significantly reduced face and object inversion effects relative to the other two groups. This was accounted for by BDD participants being significantly more accurate in identifying inverted Mooney faces and objects than the other participants. Conclusions: These data were interpreted as reflecting an overreliance on independent components at the expense of holistic (configural) processing in BDD. (JINS, 2017, 23, 471–480)
Objectives: Evidence suggests that Alzheimer’s disease (AD) biomarkers become abnormal many years before the emergence of clinical symptoms of AD, raising the possibility that biomarker levels measured in cognitively normal individuals would be associated with cognitive performance many years later. This study examined whether performance on computerized cognitive tests is associated with levels of cerebrospinal fluid (CSF) biomarkers of amyloid, tau, and phosphorylated tau (p-tau) obtained approximately 10 years earlier, when individuals were cognitively normal and primarily middle-aged. Methods: Individuals from the BIOCARD cohort (mean age at testing=69 years) were tested on two computerized tasks hypothesized to rely on brain regions affected by the early accumulation of AD pathology: (1) a Paired Associates Learning (PAL) task (n=67) and (2) a visual search task (n=86). Results: In regression analyses, poorer performance on the PAL task was associated with higher levels of CSF p-tau obtained years earlier, whereas worse performance in the visual search task was associated with lower levels of CSF Aβ1-42. Conclusions: These findings suggest that AD biomarker levels may be differentially predictive of specific cognitive functions many years later. In line with the pattern of early accumulation of AD pathology, the PAL task, hypothesized to rely on medial temporal lobe function, was associated with CSF p-tau, whereas the visual search task, hypothesized to rely on frontoparietal function, was associated with CSF amyloid. Studies using amyloid and tau PET imaging will be useful in examining these hypothesized relationships further. (JINS, 2016, 22, 968–977)
Objectives: A limited body of research is available on the relationships between multiplicity of birth and neuropsychological functioning in preterm children who were conceived in the age of assisted reproductive technology and served by the modern neonatal intensive care unit. Our chief objective was to evaluate whether, after adjustment for sociodemographic factors and perinatal complications, twin birth accounted for a unique portion of developmental outcome variance in children born at-risk in the surfactant era. Methods: We compared the neuropsychological functioning of 77 twins and 144 singletons born preterm (<34 gestational weeks) and served by William Beaumont Hospital, Royal Oak, MI. Children were evaluated at preschool age, using standardized tests of memory, language, perceptual, and motor abilities. Results: Multiple regression analyses, adjusting for sociodemographic and perinatal variables, revealed no differences on memory or motor indices between preterm twins and their singleton counterparts. In contrast, performance of language and visual processing tasks was significantly lower in twins despite reduced perinatal risk in comparison to singletons. Effect sizes ranged from .33 to .38 standard deviations for global language and visual processing ability indices, respectively. No significant group by sex interactions were observed, and comparison of first-, or second-born twins with singletons yielded medium effect sizes (Cohen’s d=.56 and .40, respectively). Conclusions: The modest twin disadvantage on language and visual processing tasks at preschool-age could not be readily attributable to socioeconomic or perinatal variables. The possibility of biological or social twinning-related phenomena as mechanisms underlying the observed performance gaps are discussed. (JINS, 2016, 22, 865–877)
This chapter focuses on visual perception, which is the dominant sense in humans and has been used from the first days of building artificial machines. It highlights the state of the art in computer vision methods that have been found to operate well and that led to the development of capabilities. The chapter summarizes the work structured into four key topics: object recognition and categorization, tracking and visual servoing, understanding human behavior, and contextual scene understanding. Scene geometry is an important intermediate representation in the interpretation process of an image. Object recognition can be seen as the challenge to determine the where and what of objects in a scene. Surveillance systems often work in two phases: a learning phase and a run-time phase. The chapter concludes with a critical assessment of what computer vision has achieved and what challenges remain.
This paper examines the relationship between the concepts of ‘seeing’ and ‘attempting/trying’ in various languages. These concepts have so far been found to be co-lexified in languages spoken in Eurasia, Papua New Guinea, India and West Africa, with an added implicature of politeness present in some languages when this lexical item is used in directives. After establishing a cross-linguistic sample, the paper proposes a specific grammaticalization mechanism as responsible for producing this semantic relationship. The explanation centers on a process involving metaphorical transfer, the loss of semantic features, generalization, and a specific syntactic context conducive to this meaning shift. First, the Mind-as-Body metaphor is applied to the mind-related notion of ‘seeing an object’ to derive the body-related notion of ‘controlling an object’, as has previously been demonstrated to be the case in the history of certain Indo-European languages. Second, semantic bleaching causes the meaning component of physical sight to be lost from the overall meaning of the morpheme, and semantic generalization allows attempted actions to be mentally treated the same as physical objects that are manipulated. Finally, the context in which this meaning shift occurs is posited as constructions involving multiverbs, such as serial verbs or converbs.
This chapter discusses the processes by which one comes to know the environment, namely sensation, perception, and recognition. Perception builds upon basic sensation by extracting more complex attributes from sensory elements. For example, visual perception includes the ability to detect motion, differentiate colors, and distinguish basic forms. Recognition involves identification of a sensory stimulus via access to and integration of stored representations of previously encountered stimuli. Acquired brain damage and developmental abnormalities may affect each level of processing, including primary sensation, cortically mediated perception, or higher-order aspects of perception or recognition. Negative perceptual symptoms involving hearing may affect primary sensory processes, secondary perceptual abilities, or recognition. Cortical auditory disorder or auditory agnosia refers to a non-specific loss of the ability to discriminate both speech and environmental auditory stimuli. Sensory loss may arise from damage at any point within the somatosensory system.
Emotions are often expressed or signaled via postures and movements of the whole body or its parts. This chapter surveys the smaller but important corpus of research devoted to investigating the perception of bodily expressed emotions and its neural substrate. It focuses on the visual cues underlying body and bodily emotion perception. The chapter begins with a consideration of what constitutes a bodily expression or signal of emotion, highlighting a difference between actions that directly convey an emotion and actions that do not but are nevertheless performed in an emotional way. It then briefly summarises studies that have demonstrated the ability of human observers to distinguish between and identify a range of emotions from body posture and movement stimuli. The chapter surveys the current state of knowledge about how the brain processes visual information relating to other people's bodies and bodily expressions of emotion.
The aim of the present study was to validate a food photograph album (FPA) as a tool to visually estimate food amounts, and to compare this estimation with that attained through the use of measuring cups (MC) and food models (FM). We tested 163 foods over fifteen sessions (thirty subjects/session; 10–12 foods presented in two portion sizes, 20–24 plates/session). In each session, subjects estimated food amounts with the assistance of FPA, MC and FM. We compared (by portion and method) the mean estimated weight and the mean real weight. We also compared the percentage error estimation for each portion, and the mean food percentage error estimation between methods. In addition, we determined the percentage error estimation of each method. We included 463 adolescents from three public high schools (mean age 17·1 (sd 1·2) years, 61·8 % females). All foods were assessed using FPA, 53·4 % of foods were assessed using MC, and FM was used for 18·4 % of foods. The mean estimated weight with all methods was statistically different compared with the mean real weight for almost all foods. However, a lower percentage error estimation was observed using FPA (2·3 v. 56·9 % for MC and 325 % for FM, P< 0·001). Also, when analysing error rate ranges between methods, there were more observations (P< 0·001) with estimation errors higher than 40 % with the MC (56·1 %), than with the FPA (27·5 %) and FM (44·9 %). In conclusion, although differences between estimated and real weight were statistically significant for almost all foods, comparisons between methods showed FPA to be the most accurate tool for estimating food amounts.
Eye fixation–related potential (EFRP) measures electrical brain activity in response to eye fixations. The aim of the current study was to investigate whether the EFRPs vary during consecutive eye fixations while subjects were performing an object identification task. Eye fixations evoked P1 and N1 components at the occipital and parietal recording sites. The latency of P1 component increased during consecutive fixations. The amplitude of P1 increased and the amplitude of N1 decreased during consecutive fixations. The results indicate that EFRPs are modulated during consecutive fixations, suggesting that the current technique may provide a useful tool to study temporal dynamics of visual perception and processes underlying object identification.