Form perception is a cognitive correlate of the relation between subitizing ability and math performance.

"Subitizing" defines a phenomenon whereby approximately four items can be quickly and accurately processed. Studies have shown the close association between subitizing and math performance, however, the mechanism for the association remains unclear. The present study was conducted to investigate whether form perception assessed on a serial figure matching task is a potential non-numerical mechanism between subitizing ability and math performance. Three-hundred and seventy-three Chinese primary school students completed four kinds of dot comparison tasks, serial figure matching task, math performance tasks (including three arithmetic computation tasks and math word problem task), and other cognitive tasks as their general cognitive abilities were observed as covariates. A series of hierarchical regression analyses showed that after controlling for age, gender, nonverbal matrix reasoning, and visual tracking, subitizing comparison (subitizing vs. subitizing, subitizing vs. estimation) still contributed to simple addition or simple subtraction but not to complex subtraction ability or math word problem. After taking form perception as an additional control variable, the predictive power of different dot comparison conditions disappeared. A path model also showed that form perception fully mediates the relation between numerosity comparison (within and beyond the subitizing range) and arithmetic performance. These findings support the claim that form perception is a non-numerical cognitive correlate of the relation between subitizing ability and math performance (especially arithmetic computation).

A review of the impairments, preserved visual functions, and neuropathology in 21 patients with visual form agnosia - A unique defect with line drawings.

We present a comprehensive review of the rare syndrome visual form agnosia (VFA). We begin by documenting its history, including the origins of the term, and the first case study labelled as VFA. The defining characteristics of the syndrome, as others have previously defined it, are then described. The impairments, preserved aspects of visual perception, and areas of brain damage in 21 patients who meet these defining characteristics are described in detail, including which tests were used to verify the presence or absence of key symptoms. From this, we note important similarities along with notable areas of divergence between patients. Damage to the occipital lobe (20/21), an inability to recognise line drawings (19/21), preserved colour vision (14/21), and visual field defects (16/21) were areas of consistency across most cases. We found it useful to distinguish between shape and form as distinct constructs when examining perceptual abilities in VFA patients. Our observations suggest that these patients often exhibit difficulties in processing simplified versions of form. Deficits in processing orientation and size were uncommon. Motion perception and visual imagery were not widely tested for despite being typically cited as defining features of the syndrome - although in the sample described, motion perception was never found to be a deficit. Moreover, problems with vision (e.g., poor visual acuity and the presence of hemianopias/scotomas in the visual fields) are more common than we would have thought and may also contribute to perceptual impairments in patients with VFA. We conclude that VFA is a perceptual disorder where the visual system has a reduced ability to synthesise lines together for the purposes of making sense of what images represent holistically.

Faster bi-stable visual switching in psychosis.

Bi-stable stimuli evoke two distinct perceptual interpretations that alternate and compete for dominance. Bi-stable perception is thought to be driven at least in part by mutual suppression between distinct neural populations that represent each percept. Abnormal visual perception is observed among people with psychotic psychopathology (PwPP), and there is evidence to suggest that these visual deficits may depend on impaired neural suppression in visual cortex. However, it is not yet clear whether bi-stable visual perception is abnormal among PwPP. Here, we examined bi-stable perception in a visual structure-from-motion task using a rotating cylinder illusion in a group of 65 PwPP, 44 first-degree biological relatives, and 43 healthy controls. Data from a 'real switch' task, in which physical depth cues signaled real switches in rotation direction were used to exclude individuals who did not show adequate task performance. In addition, we measured concentrations of neurochemicals, including glutamate, glutamine, and γ-amino butyric acid (GABA), involved in excitatory and inhibitory neurotransmission. These neurochemicals were measured non-invasively in visual cortex using 7 tesla MR spectroscopy. We found that PwPP and their relatives showed faster bi-stable switch rates than healthy controls. Faster switch rates also correlated with significantly higher psychiatric symptom levels across all participants. However, we did not observe any significant relationships across individuals between neurochemical concentrations and SFM switch rates. Our results are consistent with a reduction in suppressive neural processes during structure-from-motion perception in PwPP, and suggest that genetic liability for psychosis is associated with disrupted bi-stable perception.

Form Properties of Moving Targets Bias Smooth Pursuit Target Selection in Monkeys.

During natural viewing, we often recognize multiple objects, detect their motion, and select one object as the target to track. It remains to be determined how such behavior is guided by the integration of visual form and motion perception. To address this, we studied how monkeys made a choice to track moving targets with different forms by smooth pursuit eye movements in a two-target task. We found that pursuit responses were biased toward the motion direction of a target with a hole. By computing the relative weighting, we found that the target with a hole exhibited a larger weight for vector computation. The global hole feature dominated other form properties. This dominance failed to account for changes in pursuit responses to a target with different forms moving singly. These findings suggest that the integration of visual form and motion perception can reshape the competition in sensorimotor networks to guide behavioral selection.

Form Properties of Moving Targets Bias Smooth Pursuit Target Selection in Monkeys / 神经科学通报·英文版

During natural viewing, we often recognize multiple objects, detect their motion, and select one object as the target to track. It remains to be determined how such behavior is guided by the integration of visual form and motion perception. To address this, we studied how monkeys made a choice to track moving targets with different forms by smooth pursuit eye movements in a two-target task. We found that pursuit responses were biased toward the motion direction of a target with a hole. By computing the relative weighting, we found that the target with a hole exhibited a larger weight for vector computation. The global hole feature dominated other form properties. This dominance failed to account for changes in pursuit responses to a target with different forms moving singly. These findings suggest that the integration of visual form and motion perception can reshape the competition in sensorimotor networks to guide behavioral selection.

Reduced 2D form coherence and 3D structure from motion sensitivity in developmental dyscalculia.

Developmental dyscalculia (DD) is a specific learning disability affecting the development of numerical and arithmetical skills. The origin of DD is typically attributed to the suboptimal functioning of key regions within the dorsal visual stream (parietal cortex) which support numerical cognition. While DD individuals are often impaired in visual numerosity perception, the extent to which they also show a wider range of visual dysfunctions is poorly documented. In the current study we measured sensitivity to global motion (translational and flow), 2D static form (Glass patterns) and 3D structure from motion in adults with DD and control subjects. While sensitivity to global motion was comparable across groups, thresholds for static form and structure from motion were higher in the DD compared to the control group, irrespective of associated reading impairments. Glass pattern sensitivity predicted numerical abilities, and this relation could not be explained by recently reported differences in visual crowding. Since global form sensitivity has often been considered an index of ventral stream function, our findings could indicate a cortical dysfunction extending beyond the dorsal visual stream. Alternatively, they would fit with a role of parietal cortex in form perception under challenging conditions requiring multiple element integration.

Individual Observer Differences in the Use of Form and Motion to Perceive the Actor's Sex in Biological Motion Displays.

Recent research has shown that the perception of biological motion may be influenced by aspects of the observer's personality. In this study, we sought to determine how participant characteristics (including demographics, response inhibition, autism spectrum quotient, empathy, social anxiety, and motion imagery) might influence the use of form and motion to identify the actor's sex in biological motion displays. We varied the degree of form and motion in biological motion displays and correlated 76 young adult participants' performances for identifying the actor's sex in these varied conditions with their individual differences on variables of interest. Differences in the separate use of form and motion cues were predictive of participant performance generally, with use of form most predictive of performance. Female participants relied primarily on form information, while male participants relied primarily on motion information. Participants less able to visualize movement tended to be better at using form information in the biological motion task. Overall, our findings suggest that similar group level performances across participants in identifying the sex of the actor in a biological motion task may result from quite different individual processing.

Corrigendum: Spatial Skills Associated With Block-Building Complexity in Preschoolers.

[This corrects the article DOI: 10.3389/fpsyg.2020.563493.].

Conserved visual capacity of rats under red light.

Recent studies examine the behavioral capacities of rats and mice with and without visual input, and the neuronal mechanisms underlying such capacities. These animals are assumed to be functionally blind under red light, an assumption that might originate in the fact that they are dichromats who possess ultraviolet and green cones, but not red cones. But the inability to see red as a color does not necessarily rule out form vision based on red light absorption. We measured Long-Evans rats' capacity for visual form discrimination under red light of various wavelength bands. Upon viewing a black and white grating, they had to distinguish between two categories of orientation: horizontal and vertical. Psychometric curves plotting judged orientation versus angle demonstrate the conserved visual capacity of rats under red light. Investigations aiming to explore rodent physiological and behavioral functions in the absence of visual input should not assume red-light blindness.

A bias in saccadic suppression of shape change.

Processing of visual information in the central (foveal) and peripheral visual field is vastly different. To achieve a homogeneous representation of the visual world across eye movements, the visual system needs to compensate for these differences. By introducing subtle changes between peripheral and foveal inputs across saccades, one can test this compensation. We morphed shapes between a triangle and a circle and presented two different change directions (circularity decrease or increase) at varying magnitudes across a saccade. In a change-discrimination task, observers disproportionally often reported percepts of circularity increase. To test the relationship with visual-field differences, we measured perception when shapes were exclusively presented either in the periphery (before a saccade), or in the fovea (after a saccade). We found that overall shapes were perceived as more circular before than after a saccade and the more pronounced this difference was for a participant, the smaller was their circularity-increase bias in the change-discrimination task. We propose that visual-field differences have a direct and an indirect influence on transsaccadic perception of shape change. The direct influence is based on the distinct appearance of shape in the central and peripheral visual field in a trial, causing an increase of the perceptual magnitude of circularity-decrease changes. The indirect influence is based on long-term build-up of transsaccadic expectations; if a change is opposite (circularity increase) to the expectation (circularity decrease), it should elicit a strong error signal facilitating change detection. We discuss the concept of transsaccadic expectations and theoretical implications for transsaccadic perception of other feature changes.

Erratum: Spatial Skills Associated With Block-Building Complexity in Preschoolers.

[This corrects the article DOI: 10.3389/fpsyg.2020.563493.].

Developmental trajectories of global motion and global form perception from 4 years to adulthood.

Literature on the development of global motion and global form perception demonstrated their asynchronous developmental trajectories. However, former studies have failed to clearly establish the critical period of maturation for these specific abilities. This study aimed to analyze the developmental trajectories of global motion and global form discrimination abilities by controlling for basic visual functions and general cognitive ability and to present the global motion and global form normative scores. A sample of 456 children and adolescents (4-17 years of age) and 76 adults recruited from the Italian and Swedish general population participated in the study. Motion and form perception were evaluated by the motion coherence test and form coherence test, respectively. Raven's matrices were used to assess general cognitive ability, the Lea Hyvärinen chart test was used for full- and low-contrast visual acuity, and the TNO test was used for stereopsis. General cognitive ability and basic visual functions were strongly related to motion and form perception development. Global motion perception had an accelerated maturation compared with global form perception. For motion perception, an analysis of the oblique effect's development showed that it is present at 4 years of age. The standardized scores of global motion and form coherence tests can be used for clinical purposes.

Evaluation of oral stereognosis in completely edentulous patients with palatal tori / Evaluación de la estereognosia oral en pacientes completamente edéntulos con toros palatinos

Background: The corollary is not investigated in the completely edentulous patients with palatal tori. Objective: The aim of this study was to assess the oral stereognostic ability in completely edentulous patients with palatal tori. Material and Methods: Thirty-four completely edentulous patients aged 50 to 89 years were allocated to Group 1 (without palatal tori, n=18) and Group 2 (with palatal tori, n=16). The oral stereognostic test was conducted using 6 intraoral test pieces (circle/square/rectangle/triangle/plus/toroid) that were fabricated to standard dimensions using the light cure acrylic resin. Each test piece was placed in the patient's mouth and was asked to manipulate the test piece between the tongue and the palate. The patients identified the shapes by matching them on a shape chart. Each correct identification was assigned a score of 1. The response time taken to identify each shape was recorded. Statistical computation was done using a chi - square test and Mann-Whitney U test. Results: Significant difference was observed in the overall scoring percentages between the 2 groups (p<0.05). Group 2 had lower oral stereognostic scores compared to group 1 (p<0.05). There was no statistically significant difference in the mean response time for identifying the shapes among the groups, however group 2 patients had longer response time. Conclusion: Oral stereognostic ability of the completely edentulous patients with torus palatinus was lower when compared to completely edentulous patients without tori.

Antecedentes: el corolario no se investiga en los pacientes completamente desdentados con toros palatinos. Objetivo:El objetivo de este estudio fue evaluar la capacidad estereognóstica oral en pacientes completamente edéntulos con toros palatinos. Material y Métodos: Treinta y cuatro pacientes completamente edéntulos de 50 a 89 años fueron asignados al Grupo 1 (sin toros palatinos, n = 18) y al Grupo 2 (con toros palatinos, n = 16). La prueba estereognóstica oral se realizó utilizando 6 piezas de prueba intraorales (círculo / cuadrado / rectángulo / triángulo / cruz / aro) que se fabricaron a dimensiones estándar utilizando la resina acrílica fotopolimerizable. Cada pieza de prueba se colocó en la boca del paciente y se le pidió que manipulara la pieza de prueba entre la lengua y el paladar. Los pacientes identificaron las formas haciéndolas coincidir en un gráfico de formas. A cada identificación correcta se le asignó una puntuación de 1. Se registró el tiempo de respuesta necesario para identificar cada forma. El cálculo estadístico se realizó mediante la prueba de chi-cuadrado y la prueba U de Mann-Whitney. Resultados: Se observó una diferencia significativa en los porcentajes de puntuación generales entre los 2 grupos (p<0,05). El grupo 2 tuvo puntuaciones estereognósticas orales más bajas en comparación con el grupo 1 (p<0,05). No hubo diferencia estadísticamente significativa en el tiempo medio de respuesta para identificar las formas entre los grupos, sin embargo, los pacientes del grupo 2 tuvieron un tiempo de respuesta más largo.Conclusión: La capacidad estereognóstica oral de los pacientes completamente edéntulos con torus palatino fue menor en comparación con los pacientes completamente edéntulos sin torus.

Avaliação quantitativa por fotogrametria tridimensional e da percepção profissional das alterações faciais após lipectomia bucal / Quantitative assessment by three-dimensional photogrammetry and professional perception of facial changes after oral lipectomy

Foi propósito desse estudo identificar se existe diferença na região da bochecha através da fotogrametria tridimensional após lipectomia bucal, bem como verificar a percepção dos profissionais quanto as mudanças faciais após o procedimento. Trata-se de um ensaio clínico quase-experimental sobre a lipectomia bucal. Quinze pacientes foram operados, totalizando 30 lipectomias bucais. Um protocolo fotográfico para fotogrametria tridimensional foi realizado em dois tempos operatórios, T0: pré-operatório e T1:10 meses pós-operatório. A abertura bucal, a massa corporal, a quantidade de gordura removida em gramas e mililitros; e escala visual analógica de dor, foram coletados. Através do Formulário Google®, profissionais especialistas da Odontologia avaliaram as fotografias. A avaliação quantitativa da região subzigomática foi realizada através do programa GOM inspect® utilizado um mapa de cores e medições em 6 zonas na região da bochecha. Utilizou-se a Coeficiente de Spearman e o teste de Wilcoxon. Observou-se uma correlação negativa de baixa a moderada entre a quantidade de gordura removida e a alteração na zona facial 2 e 5 levando em consideração todas as hemifaces (p<0,028), revelando diferença estatisticamente significativa. O teste de Wilcoxon revelou diferença estatisticamente significativa em todas as zonas entre T0 e T1. O índice de acerto dos profissionais sobre T0 e T1 foi de 69,86%. A fotogrametria tridimensional conseguiu quantificar as alterações na região da bochecha após a lipectomia bucal, que apesar de milimétricas, foram perceptíveis por profissionais. A área subzigomática na zona 2 e 5 foi a região que mais diminui após a remoção do CAB (AU).

The purpose of this study was to identify whether there is a difference in the cheek region through three-dimensional photogrammetry after oral lipectomy, as well as to verify the perception of professionals regarding facial changes after the procedure. This is a quasiexperimental clinical trial on oral lipectomy. Fifteen patients were operated on, totaling 30 oral lipectomies. A photographic protocol for three-dimensional photogrammetry was performed in two operative stages, T0: preoperative and T1: 10 months postoperatively. The mouth opening, body mass, the amount of fat removed in grams and milliliters; and visual analogue pain scale, were collected. Through the Google® Form, dental specialists evaluated the photographs. The quantitative assessment of the subzygomatic region was performed using the GOM inspect® program, using a color map and measurements in 6 zones in the cheek region. Spearman's coefficient and the Wilcoxon test were used. A low to moderate negative correlation was observed between the amount of fat removed and the change in facial zone 2 and 5 taking into account all hemifaces (p <0.028), revealing a statistically significant difference. The Wilcoxon test revealed a statistically significant difference in all zones between T0 and T1. The professionals' success rate on T0 and T1 was 69.86%. Three-dimensional photogrammetry was able to quantify the changes in the cheek region after the oral lipectomy, which despite being millimetric, were perceived by professionals. The subzygomatic area in zones 2 and 5 was the region that decreased the most after CAB removal (AU).

Spatial Skills Associated With Block-Building Complexity in Preschoolers.

Block building is a popular play activity among young children and is also used by psychologists to assess their intelligence. However, little research has attempted to systematically explore the cognitive bases of block-building ability. The current study (N = 66 Chinese preschoolers, 32 boys and 34 girls; mean age = 4.7 years, SD = 0.29, range = 3.4 to 5.2 years) investigated the relationships between six measures of spatial skills (shape naming, shape recognition, shape composition, solid figure naming, cube transformation, and mental rotation, with the former four representing form perception and the latter two representing visualization) and block-building complexity. Correlation results showed that three of the four measures of form perception (shape naming, shape recognition, and shape composition) were significantly and positively correlated with block-building complexity, whereas the two measures of visualization were not. Results from regression models indicated that shape recognition and shape composition, as well as shape-recognition-by-gender interaction, were unique predictors of children's block-building complexity. These findings provide preliminary evidence for the basic spatial skills underlying children's block-building complexity and have implications for classroom instructions aimed at improving preschoolers' block-building complexity.

Visual form perception predicts 3-year longitudinal development of mathematical achievement.

Numerous studies have demonstrated an association between approximate number system (ANS) acuity and mathematical performance. Studies have also shown that ANS acuity can predict the longitudinal development of mathematical achievement. Visual form perception in the current investigation was proposed to account for the predictive role of ANS acuity in the development of mathematical achievement. One hundred and eighty-eight school children (100 males, 88 females; mean age = 12.2 ± 0.3 years) participated in the study by completing five tests: numerosity comparison, figure matching, mental rotation, nonverbal matrix reasoning, and choice reaction time. Three years later, they took a mathematical achievement test. We assessed whether the early tests predicted mathematical achievement at the later date. Analysis showed that the ANS acuity measured via numerosity comparison significantly predicted mathematical achievement 3 years later, even when controlling for individual differences in mental rotation, nonverbal matrix reasoning, and choice reaction time, as well as age and gender differences. Hierarchical regression and mediation analyses further showed that the longitudinal predictive role of ANS acuity in mathematical achievement was interpreted by visual form perception measured with a figure-matching test. Together, these results indicate that visual form perception may be the underlying cognitive mechanism that links ANS acuity to mathematical achievement in terms of longitudinal development.

Play enhances visual form perception in infancy-an active training study.

Motor experiences and active exploration during early childhood may affect individual differences in a wide range of perceptual and cognitive abilities. In the current study, we suggest that active exploration of objects facilitates the ability to process object forms and magnitudes, which in turn impacts the development of numerosity perception. We tested our hypothesis by conducting a preregistered active exploration intervention with 59 8-month-old infants. The minimal intervention consisted of actively playing with and exploring blocks once a day for 8 weeks. In order to control for possible training effects on attention, we used book reading as a control condition. Pre- and post-test assessments using eye-tracking showed that block play improved visual form perception, where infants became better at detecting a deviant shape. Furthermore, using three control tasks, we showed that the intervention specifically improved infants' ability to process visual forms and the effect could not be explained by a domain general improvement in attention or visual perception. We found that the intervention did not improve numerosity perception and suggest that because of the sequential nature of our hypothesis, a longer time frame might be needed to see improvements in this ability. Our findings indicate that if infants are given more opportunities for play and exploration, it will have positive effects on their visual form perception, which in turn could help their understanding of geometrical concepts.

The effect of mild traumatic brain injury on the visual processing of global form and motion.

Cortical visual processing involves the ventral stream (form perception) and the dorsal stream (motion perception). We assessed whether mild traumatic brain injury (TBI) differentially affects these two streams. Eleven adults with mild TBI (28 ± 9 yrs, 17 ± 5 months post injury) and 25 controls (25 ± 5 yrs) participated. Participants completed tests of global processing involving Glass patterns (form) and random dot kinematograms (motion), measurement of contrast thresholds for motion direction discrimination, a comprehensive vision screening and the Post-Concussion Symptom Inventory (PCSI). Our results showed that the mild TBI group had significantly higher (worse) global form (mean ± SD: TBI 25 ± 6%, control 21 ± 5%) and motion (TBI 14 ± 7%, control 11 ± 3%) coherence thresholds than controls. The magnitude of the mild TBI group deficit did not differ between the two tasks. Contrast thresholds for motion direction discrimination did not differ between the groups, but were positively correlated with PCSI score (r2 = 0.51. p = 0.01) in the mild TBI group. The mild TBI group had worse outcomes than controls for all clinical measurements of vision except distance visual acuity. In conclusion, mild TBI affects processing in both the dorsal and ventral cortical processing streams equally. In addition, spatiotemporal contrast sensitivity may be related to the symptoms of mild TBI.

Visual form perception is fundamental for both reading comprehension and arithmetic computation.

Visual perception has been found to be a critical factor for reading comprehension and arithmetic computation in separate lines of research with different measures of visual form perception. The current study of 1099 Chinese elementary school students investigated whether the same visual form perception (assessed by a geometric figure matching task) underlies both reading comprehension and arithmetic computation. The results showed that visual form perception had close relations with both reading comprehension and arithmetic computation, even after controlling for age, gender, and cognitive factors such as processing speed, attention, working memory, visuo-spatial processing, and general intelligence. Results also showed that numerosity comparison's relations with reading comprehension and arithmetic computation were fully accounted for by visual form perception. These results suggest that reading comprehension and arithmetic computation might share a similar visual form processing mechanism.

Do different experimental tasks affect psychophysical measurements of motion perception in autism-spectrum disorder? An analysis.

There is a rapid increase in the number of individuals with high-functioning autism (HFA). Research on motion perception in HFA has shown deficits in processing motion information at the higher visual cortical areas (V5/middle temporal). Several hypotheses have been put forth to explain these deficits as being due to enhanced processing of small details at the expense of the global picture or as a global integration abnormality. However, there is a lot of variability in the results obtained from experiments designed to study motion in adults with autism. These could be due to the inherent diagnostic differences within even the same range of the autism spectrum and/or due to comparison of different experimental paradigms whose processing by the same visual neural areas could be different. In this review, we discuss the various results on motion processing in HFA, as well as the theories of motion perception in autism.