Coordinated changes in a cortical circuit sculpt effects of novelty on neural dynamics.

Recent studies have found dramatic cell-type-specific responses to stimulus novelty, highlighting the importance of analyzing the cortical circuitry at this granularity to understand brain function. Although initial work characterized activity by cell type, the alterations in cortical circuitry due to interacting novelty effects remain unclear. We investigated circuit mechanisms underlying the observed neural dynamics in response to novel stimuli using a large-scale public dataset of electrophysiological recordings in behaving mice and a population network model. The model was constrained by multi-patch synaptic physiology and electron microscopy data. We found generally weaker connections under novel stimuli, with shifts in the balance between somatostatin (SST) and vasoactive intestinal polypeptide (VIP) populations and increased excitatory influences on parvalbumin (PV) and SST populations. These findings systematically characterize how cortical circuits adapt to stimulus novelty.

Do Children with High Callous-Unemotional Traits Have Attentional Deficits to Emotional Stimuli? Evidence from a Multi-Method and Multi-Informant Study.

Callous-unemotional (CU) traits in children and adolescents are linked to severe and persistent antisocial behavior. Based on past empirical research, several theoretical models have suggested that CU traits may be partly explained by difficulties in correctly identifying others' emotional states as well as their reduced attention to others' eyes, which could be important for both causal theory and treatment. This study tested the relationships among CU traits, emotion recognition of facial expressions and visual behavior in a sample of 52 boys referred to a clinic for conduct problems (Mage = 10.29 years; SD = 2.06). We conducted a multi-method and multi-informant assessment of CU traits through the Child Problematic Traits Inventory (CPTI), the Inventory of Callous-Unemotional (ICU), and the Clinical Assessment of Prosocial Emotions-Version 1.1 (CAPE). The primary goal of the study was to compare the utility of these methods for forming subgroups of youth that differ in their emotional processing abilities. An emotion recognition task assessed recognition accuracy (percentage of mistakes) and absolute dwell time on the eyes or mouth region for each emotion. Results from repeated measures ANOVAs revealed that low and high CU groups did not differ in emotion recognition accuracy, irrespective of the method of assessing CU traits. However, the high CU group showed reduced attention to the eyes of fearful and sad facial expressions (using the CPTI) or to all emotions (using the CAPE). The high CU group also showed a general increase in attention to the mouth area, but only when assessed by the CAPE. These findings provide evidence to support abnormalities in how those elevated on CU traits process emotional stimuli, especially when assessed by a clinical interview, which could guide appropriate assessment and more successful interventions for this group of youth.

A pupillary contrast response in mice and humans: Neural mechanisms and visual functions.

In the pupillary light response (PLR), increases in ambient light constrict the pupil to dampen increases in retinal illuminance. Here, we report that the pupillary reflex arc implements a second input-output transformation; it senses temporal contrast to enhance spatial contrast in the retinal image and increase visual acuity. The pupillary contrast response (PCoR) is driven by rod photoreceptors via type 6 bipolar cells and M1 ganglion cells. Temporal contrast is transformed into sustained pupil constriction by the M1's conversion of excitatory input into spike output. Computational modeling explains how the PCoR shapes retinal images. Pupil constriction improves acuity in gaze stabilization and predation in mice. Humans exhibit a PCoR with similar tuning properties to mice, which interacts with eye movements to optimize the statistics of the visual input for retinal encoding. Thus, we uncover a conserved component of active vision, its cell-type-specific pathway, computational mechanisms, and optical and behavioral significance.

Correlation research on visual behavior and cognition of impression against localized church facades in China.

Churches in China are material witnesses of cultural dissemination, and their architectural forms are in the process of localization. In order to determine the optimal degree of localization of church facades as well as to study the correlation between visual behavior and subjective cognition, five church facades with different degrees of localization were selected in present study, and the questionnaire survey as well as eye-tracking technology were used to collect data from two aspects: subjective cognition (the impression and acceptance levels) and objective eye movement (the first fixation duration, total fixation duration, fixation count, and visit count). The results showed the differences in public perceptions of church facades, and the impression of participants was continuously enhanced with the increasing of localization degree of church facade, while the acceptance level showed a U-shaped change. What's more, the correlation between the impression level and the first fixation duration was found to be 0.910, the Pearson coefficient between the acceptance level and the total fixation duration was found to be 0.928, indicating that eye-tracking indicators could accurately reflect the subjective cognition of the public. Performed analyses demonstrated that eye-tracking technology would provides an important technical mean for the design, conservation, and renewal of building facades.

Unraveling the impact of fog on driver behavior in highway tunnel entrances: A field experiment.

OBJECTIVES: This research aims to (1) study the visual and psychological characteristics of drivers in foggy tunnel entrances, (2) compare driver behavior inside and outside foggy tunnels, and (3) propose improvement ideas based on the study results. METHODS: A realistic vehicle trial was conducted. Eight participants completed trials in both foggy and clear zones on the same roadway. Drivers' physiological and psychological properties were analyzed using gaze, saccade, pupil, and heart rate as primary indicators. Pupil area change rate and heart rate variability (HRV) were used as secondary indicators. RESULTS: Visibility and tunnel area had a significant impact on drivers' visual and psychological traits. For instance, drivers in the foggy zone exhibited longer fixation duration, larger pupil area, faster heart rate, and greater HRV. Moreover, the foggy zone inside the tunnel heightened drivers' visual discomfort and psychological tension. CONCLUSION: The study suggests a high risk associated with driving in the entrance area of highway tunnels during foggy conditions, particularly after entering the tunnel. This situation significantly increases drivers' visual and psychological load. Furthermore, the effectiveness of retro-reflective facilities diminishes. Therefore, employing more self-illuminated or actively illuminated visual guiding facilities is recommended to aid drivers in acquiring traffic information.

Embodied planning in climbing: how pre-planning informs motor execution.

Introduction: The aim of the study is to address embodied planning in climbing. Embodied planning was conceptualized as the interaction between perceptual-cognitive pre-planning and motor execution. Methods: In an experimental study, 18 climbers were asked to pre-plan a climbing route and to perform the route afterward. During pre-planning, the visual search pattern of climbers was captured using a portable eye tracker. After previewing, they were invited to climb the wall. Results: Results revealed that holds looked at during pre-planning were used twice as much during route execution than those not looked at. The duration of fixations was longer for holds used than those not used during route execution. The experience of climbers (training years) correlated with visual strategies and climbing performance, such that experienced participants climbed faster and fixated at the holds not used for a shorter time. Discussion: The visual behaviors of climbers were influenced by their past sensorimotor experiences during route previewing, impacting subsequent climbing performance.

Artificial Retina Based on Organic Heterojunction Transistors for Mobile Recognition.

The flicker frequency of incident light constitutes a critical determinant in biology. Nevertheless, the exploration of methods to simulate external light stimuli with varying frequencies and develop artificial retinal neurons capable of responsive behavior remains an open question. This study presents an artificial neuron comprising organic phototransistors. The triggering properties of neurons are modulated by optical input, enabling them to execute rudimentary synaptic functions, emulating the biological characteristics of retinal neurons. The artificial retinal neuron exhibits varying responses to incoming light frequencies, allowing it to replicate the persistent visual behavior of the human eye and facilitating image discrimination. Additionally, through seamless integration with circuitry, it can execute motion recognition on a machine cart, preventing collisions with high-speed obstacles. The artificial retinal neuron offers a cost-effective and energy-efficient route for future mobile robot processors.

Retinal ganglion cell topography and spatial resolving power in the pajama cardinalfish Sphaeramia nematoptera (Bleeker, 1856).

We studied the topography of retinal ganglion cells (GCs) and estimated spatial resolving power (SRP) in the pajama cardinalfish Sphaeramia nematoptera (Bleeker, 1856), a relatively small brightly colored fish inhabiting coral reefs and lagoons in the Western Pacific. S. nematoptera is an active night predator feeding on near-bottom animal plankton and benthos. DAPI staining was used to label nuclei of GCs and non-GCs in the inner plexiform and ganglion cell layers. Non-GCs were distinguished from GCs in Nissl-stained retinal wholemounts based on cell size, shape, and staining intensity. The proportion of displaced amacrine cells (DACs) varied from 15.46 ± 1.12 (visual streak [VS]) to 17.99 ± 1.06% (dorsal periphery) (mean ± S.E.M., N = 5); the respective proportions of glial cells were 6.61 ± 0.84 and 5.89 ± 0.76%. Thus, 76%-78% of cells in the ganglion cell layer and inner plexiform layer were GCs. The minimum spatial coverage of GCs (3600-4600 cells/mm2) was detected in the dorsal and ventral periphery. It gradually increased toward the central retina to form a moderate VS. The maximum GC density (11,400-12,400 cells/mm2) was registered in the central portion of the VS. No pronounced concentric retinal specializations were found. The total number of GCs ranged within 595.2-635.9 × 103. The anatomical spatial resolving power was minimum in the ventral periphery (4.91-5.53 cpd) and maximum in the central portion of the VS (8.47-9.07 cpd). The respective minimum separable angles were 0.18-0.20° and 0.11-0.12°. The relatively high spatial resolving power and presence of the VS in the pajama cardinalfish are in line with its highly visual behavior.

[A review of studies on visual behavior analysis aided diagnosis of autism spectrum disorders].

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social communication and repetitive behaviors. With the rapid development of computer vision, visual behavior analysis aided diagnosis of ASD has got more and more attention. This paper reviews the research on visual behavior analysis aided diagnosis of ASD. First, the core symptoms and clinical diagnostic criteria of ASD are introduced briefly. Secondly, according to clinical diagnostic criteria, the interaction scenes are classified and introduced. Then, the existing relevant datasets are discussed. Finally, we analyze and compare the advantages and disadvantages of visual behavior analysis aided diagnosis methods for ASD in different interactive scenarios. The challenges in this research field are summarized and the prospects of related research are presented to promote the clinical application of visual behavior analysis in ASD diagnosis.

A Visual Pathway into Central Complex for High-Frequency Motion-Defined Bars in Drosophila.

Relative motion breaks a camouflaged target from a same-textured background, thus eliciting discrimination of a motion-defined object. Ring (R) neurons are critical components in the Drosophila central complex, which has been implicated in multiple visually guided behaviors. Using two-photon calcium imaging with female flies, we demonstrated that a specific population of R neurons that innervate the superior domain of bulb neuropil, termed superior R neurons, encoded a motion-defined bar with high spatial frequency contents. Upstream superior tuberculo-bulbar (TuBu) neurons transmitted visual signals by releasing acetylcholine within synapses connected with superior R neurons. Blocking TuBu or R neurons impaired tracking performance of the bar, which reveals their importance in motion-defined feature encoding. Additionally, the presentation of a low spatial frequency luminance-defined bar evoked consistent excitation in R neurons of the superior bulb, whereas either excited or inhibited responses were evoked in the inferior bulb. The distinct properties of the responses to the two bar stimuli indicate there is a functional division between the bulb subdomains. Moreover, physiological and behavioral tests with restricted lines suggest that R4d neurons play a vital role in tracking motion-defined bars. We conclude that the central complex receives the motion-defined features via a visual pathway from superior TuBu to R neurons and might encode different visual features via distinct response patterns at the population level, thereby driving visually guided behaviors.SIGNIFICANCE STATEMENT Animals could discriminate a motion-defined object that is indistinguishable with a same-textured background until it moves, but little is known about the underlying neural mechanisms. In this study, we identified that R neurons and their upstream partners, TuBu neurons, innervating the superior bulb of Drosophila central brain are involved in the discrimination of high-frequency motion-defined bars. Our study provides new evidence that R neurons receive multiple visual inputs from distinct upstream neurons, indicating a population coding mechanism for the fly central brain to discriminate diverse visual features. These results build progress in unraveling neural substrates for visually guided behaviors.

How Do Repeated Viewings in Forest Landscapes Influence Young People's Visual Behaviors and Cognitive Evaluations?

BACKGROUND: With the spread of the COVID-19 epidemic, it has gradually become normal to periodically visit and enjoy forest landscape resources in the suburbs of cities. For designers and managers of forest landscapes, exploring change in the visual behaviors and cognitive evaluations of people who repeatedly view forest landscapes and the characteristics of this change will aid the design and sustainable utilization of forest landscape resources in the suburbs of cities. PURPOSE: From the perspective of users' preferences for forest landscape space, this study explored the changes in visual behavior characteristics and psychological preference characteristics for individuals who repeatedly view forest landscapes and their drivers under different preferences. METHODS: This study collected data from 52 graduate and undergraduate students. We used a difference test to compare the differences in the visual behavior coincidence degree and the changes in psychological evaluations; a descriptive statistical analysis to explore young peoples' likes and dislikes of landscape elements; and Spearman correlation analysis to explore the correlation between the psychological evaluations and visual behaviors. MAIN RESULTS: 1. At the second viewing, the participants' regression behavior tended to decrease for various spaces, and they were more inclined to view areas that they had not viewed before. In addition, at the second viewing, the degree of fixation behavior coincidence was generally low, and there were obvious differences across spaces; 2. The participants' feature evaluations and comprehensive evaluations for landscapes did not change significantly with their increased familiarity with the spaces; 3. There was a significant positive correlation between the participants' psychological evaluations of landscape stimuli and the degree of fixation coincidence when viewing the spaces, among which the rate of distant clarity and the degree of fixation behavior coincidence were significantly and positively correlated. Meanwhile, at the second viewing, the number of favorite elements in the lookout space, which belongs to high-preference spaces, noticeably increased.

Routine binocular examination of young Taiwanese adults as a predictor of visual behavior performance.

BACKGROUND: Morgan and Scheiman's Optometric Extension Program (OEP) expected binocular vision findings have longstanding use in optometry. With technological advances, the demands and standards of binocular function have changed. This study aimed to investigate which binocular visual functions can effectively predict visual behavior performance. METHODS: Participants aged 15-24 years were recruited from two colleges and two universities. After completing the CSMU-Visual Behavioral Performance questionnaire (CSMU-VBP, with four components: near work, visual perception, visual comfort, and whole-body balance), participants were divided into symptomatic and asymptomatic groups based on questionnaire findings (cutoff: < 12 vs. ≥ 12 symptoms). Then a 24-step binocular visual examination was undertaken. Data were analyzed with one-sample, Student's, and paired t-tests. Additionally, receiver operating characteristic analysis was used to determine the predictors of binocular visual function required for near work, visual perception, visual comfort, and body balance dimensions. RESULTS: Among 308 participants, 43 (14%) and 265 (86%) were symptomatic and asymptomatic, respectively. Among the 46 participants with abnormal binocular vision, 36 (78%) reported that they had no obvious symptoms. The commonest dysfunctions were accommodative excess and convergence excess. Most of the binocular visual findings significantly diverged from traditional normal values: amplitude of accommodation, as well as base-in prism to break and recovery points at distance were higher than traditional normal values, whereas others were lower than traditional normal values. Total CSMU-VBP scores indicated that the asymptomatic and symptomatic groups had significant differences in DBO recovery (t = 2.334, p = 0.020) and BAF (t = 1.984, p = 0.048). Receiver operating characteristic curve analysis yielded the following binocular visual functional cutoff points: near work (DBO blur < 7, DBO recovery < 5.5), visual perception (MAF < 10.5, BAF < 10.25), visual comfort (DLP < - 2.25, DBI break > 11.5, NBI blur > 15, NBI break > 17.5, NBI recovery > 13, NPC < 5.75), and body balance (NFD_H > - 0.5, gradient AC/A [minus] > 2.25, NPC < 4.75). CONCLUSIONS: The mean values of binocular visual function among young Taiwanese adults were statistically different from traditional normative values. Further research is required to confirm whether these findings reflect impaired binocular vision or stringent criteria. Assessments of binocular visual function, especially binocular accommodation sensitivity, are crucial in routine optometric examination.

The Multidisciplinary Guidelines for Diagnosis and Referral in Cerebral Visual Impairment.

Introduction: Cerebral visual impairment (CVI) is an important cause of visual impairment in western countries. Perinatal hypoxic-ischemic damage is the most frequent cause of CVI but CVI can also be the result of a genetic disorder. The majority of children with CVI have cerebral palsy and/or developmental delay. Early diagnosis is crucial; however, there is a need for consensus on evidence based diagnostic tools and referral criteria. The aim of this study is to develop guidelines for diagnosis and referral in CVI according to the grade method. Patients and Methods: We developed the guidelines according to the GRADE method 5 searches on CVI (children, developmental age ≤ 18 years) were performed in the databases Medline, Embase, and Psychinfo, each with a distinct topic. Results: Based on evidence articles were selected on five topics: 1. Medical history and CVI-questionnaires 23 (out of 1,007). 2. Ophthalmological and orthoptic assessment 37 (out of 816). 3. Neuropsychological assessment 5 (out of 716). 4. Neuroradiological evaluation and magnetic resonance imaging (MRI) 9 (out of 723). 5. Genetic assessment 5 (out of 458). Conclusion: In medical history taking, prematurity low birth weight and APGAR (Appearance, Pulse, Grimace, Activity, Respiration) Scores (<5) are important. Different questionnaires are advised for children under the age of 3 years, older children and for specific risk groups (extremely preterm). In ophthalmological examination, eye movements, specially saccades, accommodation, crowding, contrast sensitivity and visual fields should be evaluated. OCT can show objective signs of trans-synaptic degeneration and abnormalities in fixation and saccades can be measured with eye tracking. Screening of visual perceptive functioning is recommended and can be directive for further assessment. MRI findings in CVI in Cerebral Palsy can be structured in five groups: Brain maldevelopment, white and gray matter lesions, postnatal lesions and a normal MRI. In children with CVI and periventricular leukomalacia, brain lesion severity correlates with visual function impairment. A differentiation can be made between cortical and subcortical damage and related visual function impairment. Additional assessments (neurological or genetic) can be necessary to complete the diagnosis of CVI and/or to reveal the etiology.

Factors Affecting Human Visual Behavior and Preference for Sneakers: An Eye-Tracking Study.

Human visual behavior on a product significantly affects their purchasing behavior during online shopping. In this study, two experimental studies were performed to investigate human visual behavior and preference for sneakers using an eye tracking technology. The first study discovered that shoelace and vamp areas of interests (AOIs) attracted more attention than the other AOIs. The second study explored the factors affecting human behavior on sneakers, which employed 30 students from different professional backgrounds (i.e., such as fashion and non-fashion disciplines), and examined 24 sneakers, i.e., combinations of four shoelace styles and six vamp materials. The results showed that both genders irrespective of their professional backgrounds were more concerned about the shoelaces than vamps. The shoelace AOI gained more attention of females than males, while the vamp AOI was more concerned by males than females. The vamp AOI was more concerned by non-professionals than professionals, while the shoelace AOI was paid more attention by professionals than non-professionals. Besides, flat or round shoelaces, canvas, and cow leather or cotton flannel vamp materials were more preferred by the participants than the other types. The findings are of great help for the fashion product designers, the manufacturers, and the sellers to provide the product required by the customers.

Improvements of Warning Signs for Black Ice Based on Driving Simulator Experiments.

Black ice is one of the main causes of traffic accidents in winter, and warning signs for black ice are generally ineffective because of the lack of credible information. To overcome this limitation, new warning signs for black ice were developed using materials that change color in response to different temperatures. The performance and effects of the new signs were investigated by conducting driver behavior analysis. To this end, driving simulator experiments were conducted with 37 participants for two different rural highway sections, i.e., a curve and a tangent. The analysis results of the driving behavior and visual behavior experiments showed that the conventional signs had insufficient performance in terms of inducing changes in driving behavior for safety. Meanwhile, the new signs actuated by weather conditions offered a statistically significant performance improvement. Typically, driver showed two times higher speed deceleration when they fixed eyes on the new weather-actuated warning sign (12.80 km/h) compared to the conventional old warning sign (6.84 km/h) in the curve segment. Accordingly, this study concluded that the new weather-actuated warning signs for black ice are more effective than the conventional ones for accident reduction during winters.

Mind Maps: Processed as Intuitively as Thought? Investigating Late Elementary Students' Eye-Tracked Visual Behavior Patterns In-Depth.

In this study, 44 late elementary students' visual behavior patterns when reading mind maps were investigated, more particularly, the intuitive processing nature of their visual characteristics, reading sequence and presentation mode (i.e., mind map before or after text). Eye-tracked data were investigated by means of static early attention and dynamic educational process mining (EPM) analysis and combined with learning performance and retrospective interview data. All students seem to struggle with the map's radial structure during initial reading. Also, the picture's position in the map diverts students from consecutively reading interconnected branches. EPM analyses revealed different reading patterns in proceeding reading behavior. Students receiving a text first, seem to grasp the radial structure slightly more and show higher information integration attempts. They also attained higher free recall and coherence scores. The study concludes with instructional design principles for urgently needed explicit visual literacy instruction in elementary grades.

Quiet Eye as a Mechanism for Table Tennis Performance under Fatigue and Complexity.

QE is the final ocular fixation that precedes critical athletic movements and that enables athletes to gather relevant information and organize their subsequent movement. Although little is known about the factors sustaining performance in table tennis, to date there has been no investigation to assess QE as a contributor to table tennis performance. Furthermore, there is limited research regarding the influence on QE of factors that are known to impact performance, such as task complexity and fatigue. In a within-subjects experimental design, we manipulated fatigue (high vs low) and task complexity (high vs low). Eleven elite table tennis players (mage =14.72 years, mexperience = 7.27 years) underwent each of the four resulting conditions. Athletes made longer QE before hit versus missed shots (p <.001, η2p = .795) and QE and performance decreased under fatigue (p = 0.02, η2p = .628; p = .002, η2p = .62), but we did not detect a significant effect of complexity on QE (p = .352, η2p = .087). This study is one of the first to show that QE sustains performance in a dynamic sport, that is table tennis, and that QE is affected by fatigue.

The impact of eye-tracking on patient safety in critical care.

Patient safety has become a high priority in health care. The recognition, prevention and reduction of human errors are crucial for patient care. Diverse approaches to analyze roots of errors exist, however they all bear relevant limitations. In contrast, the technology of eye-tracking offers objective and measurable parameters linked to eye movements, allowing temporal and spatial assessment of visual patterns. Diverse studies in critical care have proved the usefulness of eye-tracking to analyze real-life scenarios. These insights could contribute to increased patient safety.

Linking integrity of visual pathways trajectories to visual behavior deficit in very preterm infants.

Low-risk premature infants often develop visual deficits, even in the absence of ophthalmological complications and high-graded brain injury. These complications can be explained by the nature of subtle perinatal lesions and alterations of brain growth due to the prematurity. Subtle brain injuries and vulnerability of axonal pathways can be observed in spatiotemporal context of the white matter segments. The aim of this study was to examine the link between MRI quantitative (brain metrics data) and qualitative features (visibility of 2nd white matter segment - sagittal strata and periventricular crossroads C1-C6) and visual behavior in preterm neonates at term-equivalent age. Seventy-one very preterm infants without high-graded brain injury on MRI and no ocular pathologies were studies. The infants received MRI scans at term-equivalent age. MRI scans were analyzed using (a) simple brain metrics and (b) scoring the visibility of transient structural patterns (sagittal strata and periventricular crossroads). At the median age of 41+5 PMA weeks infants completed the Neonatal Visual Assessment. Results indicated that visibility of temporal crossroad area C6 and frontal and occipital sagittal strata was positively correlated with visual tracking skills in neonatal period. Furthermore, the visibility of frontal and occipital sagittal strata were strong predictors of total Neonatal Visual Assessment score. The findings confirmed that sagittal strata and periventricular crossroads prominence is a valuable additional marker in perinatal neuroimaging at term-equivalent age. Thus, alteration in MRI appearance of temporal crossroad and sagittal strata may be useful in predicting of visual behavior for very premature born infants.

Retinal ganglion cell distribution and spatial resolution in the Asiatic toad Bufo gargarizans (Günther, 1859).

Vision plays a crucial role in the biology of anurans. The spatial arrangement of retinal ganglion cells (GCs) is closely related to visual behavior in vertebrates. There is scarce data on GC topography in anurans, in particular, in toads. I studied the number and distribution of GCs in the retina of the Asiatic toad Bufo gargarizans. GCs were unevenly distributed across the retina. Their spatial density was minimum in the dorsal periphery (3374 and 2486 cells/mm2 in the smaller and larger toad, respectively). It increased towards the retinal equator, where a moderately pronounced visual streak was observed comprising several "patches" of a greater GC density. The streak had somewhat "vague" dorsal and ventral borders. The maximum GC density (8605 and 7282 cells/mm2 in the smaller and larger toad, respectively) was found in the temporal retina, slightly dorsal to the equator. The respective zone was identified as an area centralis. The total GC number ranged from 266 × 103 (smaller toad) to 309 × 103 cells (larger toad). The spatial resolution as estimated from eye geometry and GC density in air was minimum in the dorsal periphery (0.90 and 0.79 cycles per degree in smaller and larger toads, respectively) and maximum in the area centralis (1.43 and 1.36 cycles per degree in smaller and larger toads, respectively). Both retinal specializations found in the Asiatic toad match its biology.