Visual Matching Task Research Articles

The uphill battle for action-specific perception.

The action-specific account of perception states that a perceiver's ability to act influences the perception of the environment. For example, participants tend to perceive distances as farther when presented up hills than on the flat ground. This tendency is known as the distance-on-hill effect. However, there is debate as to whether these types of effects are truly perceptual. Critics of the action-specific account of perception claim that the effects could be due to participants guessing the hypothesis and trying to comply with the experimental demands. The present study aims to explore the distance-on-hill effect and determine whether it is truly perceptual or whether past results were due to response bias. Participants judged the relative distance to targets on a hill and the flat ground. We found the distance-on-hill effect in virtual reality using a visual matching task. The distance-on-hill effect persisted even when participants were given explicit feedback about their estimates. We also found that the effect went away, as predicted by a perceptual explanation, when participants had to match the distance between two cones that were both on hills. These results offer important steps toward the painstaking task of determining whether action's effect on perception is truly perceptual.

Auditory⁻Visual Matching of Conspecifics and Non-Conspecifics by Dogs and Human Infants.

Simple SummaryComparative investigations on infants’ and dogs’ social and communicative skills revealed striking similarity, which can be attributed to convergent evolutionary and domestication processes. Using a suitable experimental method that allows systematic and direct comparisons of dogs and humans is essential. In the current study, we used non-invasive eye-tracking technology in order to investigate looking behaviour of dogs and human infants in an auditory–visual matching task. We found a similar gazing pattern in the two species when they were presented with pictures and vocalisations of a dog and a female human, that is, both dogs and infants looked longer at the dog portrait during the dog’s bark, while matching human speech with the human face was less obvious. Our results suggested different mechanisms underlying this analogous behaviour and highlighted the importance of future investigations into cross-modal cognition in dogs and humans.We tested whether dogs and 14–16-month-old infants are able to integrate intersensory information when presented with conspecific and heterospecific faces and vocalisations. The looking behaviour of dogs and infants was recorded with a non-invasive eye-tracking technique while they were concurrently presented with a dog and a female human portrait accompanied with acoustic stimuli of female human speech and a dog’s bark. Dogs showed evidence of both con- and heterospecific intermodal matching, while infants’ looking preferences indicated effective auditory–visual matching only when presented with the audio and visual stimuli of the non-conspecifics. The results of the present study provided further evidence that domestic dogs and human infants have similar socio-cognitive skills and highlighted the importance of comparative examinations on intermodal perception.

Understanding the mechanisms behind the sexualized-body inversion hypothesis: The role of asymmetry and attention biases.

A controversial hypothesis, named the Sexualized Body Inversion Hypothesis (SBIH), claims similar visual processing of sexually objectified women (i.e., with a focus on the sexual body parts) and inanimate objects as indicated by an absence of the inversion effect for both type of stimuli. The current study aims at shedding light into the mechanisms behind the SBIH in a series of 4 experiments. Using a modified version of Bernard et al.´s (2012) visual-matching task, first we tested the core assumption of the SBIH, namely that a similar processing style occurs for sexualized human bodies and objects. In Experiments 1 and 2 a non-sexualized (personalized) condition plus two object-control conditions (mannequins, and houses) were included in the experimental design. Results showed an inversion effect for images of personalized women and mannequins, but not for sexualized women and houses. Second, we explored whether this effect was driven by differences in stimulus asymmetry, by testing the mediating and moderating role of this visual feature. In Experiment 3, we provided the first evidence that not only the sexual attributes of the images but also additional perceptual features of the stimuli, such as their asymmetry, played a moderating role in shaping the inversion effect. Lastly, we investigated the strategy adopted in the visual-matching task by tracking eye movements of the participants. Results of Experiment 4 suggest an association between a specific pattern of visual exploration of the images and the presence of the inversion effect. Findings are discussed with respect to the literature on sexual objectification.

Speech understanding in noise in elderly adults: the effect of inhibitory control and syntactic complexity.

Previous research has suggested that speech perception in elderly adults is influenced not only by age-related hearing loss or presbycusis but also by declines in cognitive abilities, by background noise and by the syntactic complexity of the message. To gain further insight into the influence of these cognitive as well as acoustic and linguistic factors on speech perception in elderly adults by investigating inhibitory control as a listener characteristic and background noise type and syntactic complexity as input characteristics. Phoneme identification was measured in different noise conditions and in different linguistic contexts (single words, sentences with varying syntactic complexity). Additionally, inhibitory control was measured using a visual stimulus-response matching task. Fifty-one adults participated in this study, including elderly adults with age-related hearing loss (n = 9) and with normal hearing (n = 17), and a control group of normal hearing younger adults (n = 25). The analysis revealed that elderly adults with normal hearing and with hearing loss were less likely to identify successfully phonemes in single words than younger normal hearing controls. In the context of sentences, only elderly adults with hearing loss had a lower odds of correct phoneme perception than the control group. Additionally, in elderly adults with hearing loss, phoneme-in-sentence perception was linked to age-related declines in inhibitory control. In all participants, phoneme identification in sentences was influenced by both noise type and syntactic complexity. Inhibitory control and syntactic complexity might play a significant role in speech perception, especially in elderly listeners. These factors might also influence the results of clinical assessments of speech perception. Testing procedures thus need to be selected and their results interpreted carefully with these influences in mind.

Occipital and parietal cortex encode representations of match between a viewed and sought object during visual target search

During a visual target search task, a stored representation of a search object is continually compared to a sensory representation of a currently-viewed visual scene. This comparison is likely to be performed through feedback modulation of sensory responses in higher visual areas, resulting in a representation of a variable encoding the conjunction between the viewed and sought objects (i.e. a "match" or decision signal) (Pagan, Urban, Wohl, & Rust, 2013). To investigate the evolution of this "match" representation in human cortex, we trained subjects to perform a visual matching task using Fribble object stimuli. A set of 8 objects was used for both the sought and viewed object, so that each of 64 possible sought object/viewed object combinations was sampled. We used multiband 3T BOLD fMRI to record changes in activation in visual occipital and parietal cortex while subjects performed this task. We used a linear support vector machine classifier, trained on activation patterns in each independently-defined ROI, to decode the identity of the viewed object, as well as the presence of a match between the viewed and sought objects. Within several regions of early visual cortex, we found that decoding of the viewed object was above chance, while decoding of an item's status as a match was at chance levels. In contrast, in several higher visual regions in ventral and lateral occipital cortex, we found that the viewed object could not be decoded, but the presence or absence of a match could be decoded with above-chance accuracy. These results suggest a transition across the ventral visual stream from predominantly stimulus-driven representations to abstract representations of task variables. Meeting abstract presented at VSS 2017

Preschool negative emotionality predicts activity and connectivity of the fusiform face area and amygdala in later childhood.

Negative emotionality (NE) refers to individual differences in the propensity to experience and react with negative emotions and is associated with increased risk of psychological disorder. However, research on the neural bases of NE has focused almost exclusively on amygdala activity during emotional face processing. This study broadened this framework by examining the relationship between observed NE in early childhood and subsequent neural responses to emotional faces in both the amygdala and the fusiform face area (FFA) in a late childhood/early adolescent sample. Measures of NE were obtained from children at age 3 using laboratory observations, and functional magnetic resonance imaging (fMRI) data were collected when these children were between the ages of 9 and 12 while performing a visual stimulus identity matching task with houses and emotional faces as stimuli. Multiple regression analyses revealed that higher NE at age 3 is associated with significantly greater activation in the left amygdala and left FFA but lower functional connectivity between these two regions during the face conditions. These findings suggest that those with higher early NE have subsequent alterations in both activity and connectivity within an extended network during face processing.

Body schema and corporeal self-recognition in the alien hand syndrome.

The alien hand syndrome (AHS) is a rare neuropsychological disorder characterized by involuntary, yet purposeful, hand movements. Patients with the AHS typically complain about a loss of agency associated with a feeling of estrangement for actions performed by the affected limb. The present study explores the integrity of the body representation in AHS, focusing on 2 main processes: multisensory integration and visual self-recognition of body parts. Three patients affected by AHS following a right-hemisphere stroke, with clinical symptoms akin to the posterior variant of AHS, were tested and their performance was compared with that of 18 age-matched healthy controls. AHS patients and controls underwent 2 experimental tasks: a same-different visual matching task for body postures, which assessed the ability of using your own body schema for encoding others' body postural changes (Experiment 1), and an explicit self-hand recognition task, which assessed the ability to visually recognize your own hands (Experiment 2). As compared to controls, all AHS patients were unable to access a reliable multisensory representation of their alien hand and use it for decoding others' postural changes; however, they could rely on an efficient multisensory representation of their intact (ipsilesional) hand. Two AHS patients also presented with a specific impairment in the visual self-recognition of their alien hand, but normal recognition of their intact hand. This evidence suggests that the AHS following a right-hemisphere stroke may involve a disruption of the multisensory representation of the alien limb; instead, self-hand recognition mechanisms may be spared. (PsycINFO Database Record

Sequential sensory and decision processing in posterior parietal cortex.

Decisions about the behavioral significance of sensory stimuli often require comparing sensory inference of what we are looking at to internal models of what we are looking for. Here, we test how neuronal selectivity for visual features is transformed into decision-related signals in posterior parietal cortex (area LIP). Monkeys performed a visual matching task that required them to detect target stimuli composed of conjunctions of color and motion-direction. Neuronal recordings from area LIP revealed two main findings. First, the sequential processing of visual features and the selection of target-stimuli suggest that LIP is involved in transforming sensory information into decision-related signals. Second, the patterns of color and motion selectivity and their impact on decision-related encoding suggest that LIP plays a role in detecting target stimuli by comparing bottom-up sensory inputs (what the monkeys were looking at) and top-down cognitive encoding inputs (what the monkeys were looking for).

Distances on hills look farther than distances on flat ground: Evidence from converging measures.

Distances on hills are judged as farther than when the same distance is presented on the flat ground. The hypothesized reason for this difference is because perception is influenced by the increased effort required to walk up a hill than to walk the same distance on flat ground. Alternatively, distances presented up a hill might be judged as farther for other, nonperceptual reasons such as bias from demand characteristics. To test whether distances on hills are perceived as farther or are merely judged as farther, we used a variety of measures, including visual matching and blindwalking tasks, and found similar effects across all measures. This convergence is consistent with a perceptual explanation. Second, we mined our data with the goal of making recommendations for future research on this paradigm. Although all of the perceptual measures used showed similar effects, visual matching was the only measure that had good intrasubject reliability. We recommend that future research on this action-specific effect could use any measure unless the research is geared towards individual differences, in which case, only the visual matching measure of perceived distance should be used.

Systemic Lisbon Battery: Normative Data for Memory and Attention Assessments.

BackgroundMemory and attention are two cognitive domains pivotal for the performance of instrumental activities of daily living (IADLs). The assessment of these functions is still widely carried out with pencil-and-paper tests, which lack ecological validity. The evaluation of cognitive and memory functions while the patients are performing IADLs should contribute to the ecological validity of the evaluation process.ObjectiveThe objective of this study is to establish normative data from virtual reality (VR) IADLs designed to activate memory and attention functions.MethodsA total of 243 non-clinical participants carried out a paper-and-pencil Mini-Mental State Examination (MMSE) and performed 3 VR activities: art gallery visual matching task, supermarket shopping task, and memory fruit matching game. The data (execution time and errors, and money spent in the case of the supermarket activity) was automatically generated from the app.ResultsOutcomes were computed using non-parametric statistics, due to non-normality of distributions. Age, academic qualifications, and computer experience all had significant effects on most measures. Normative values for different levels of these measures were defined.ConclusionsAge, academic qualifications, and computer experience should be taken into account while using our VR-based platform for cognitive assessment purposes.

An exploratory study of visual sequential processing in children with cochlear implants

ObjectiveThe objective of the study was to compare visual sequential processing in school-age children with cochlear implants (CIs) and their normal-hearing (NH) peers. Visual sequential processing was examined using both behavioral and an event-related potential (ERP) measures. MethodsEighteen children with CIs and nineteen children who had hearing within normal limits (NH) participated in the behavioral study. Subtests from the Test of Visual Perceptual Skills and the Sensory Integration and Praxis Test were administered to all children. ERP measures were collected from five children with CI and five age-matched peers. Peak latencies (N200 and P300) and reaction times for visual sequential processing were compared in these two groups. ResultsThe findings of the study revealed significant group differences in visual sequential memory and visuo-motor sequencing tasks suggesting that children with severe-profound hearing loss may have difficulties in visual sequential tasks. The study also revealed longer P300 latencies and longer reaction times for a visual sequential matching task in children with CI when compared to their NH peers suggesting slower or delayed processing of visual sequential stimuli. ConclusionsThis exploratory study involving behavioral and ERP measures showed that as a group, children with prelingual, severe-profound hearing loss who use CIs have difficulties with visual sequential processing. These findings may have implications for rehabilitation for children with hearing loss in the light of recent evidence that accurate and efficient processing of sequentially presented visual stimuli is important for language and reading outcomes.

How Facial Expressions of Emotion Affect Distance Perception.

Facial expressions of emotion are thought to convey expressers’ behavioral intentions, thus priming observers’ approach and avoidance tendencies appropriately. The present study examined whether detecting expressions of behavioral intent influences perceivers’ estimation of the expresser’s distance from them. Eighteen undergraduates (nine male and nine female) participated in the study. Six facial expressions were chosen on the basis of degree of threat—anger, hate (threatening expressions), shame, surprise (neutral expressions), pleasure, and joy (safe expressions). Each facial expression was presented on a tablet PC held by an assistant covered by a black drape who stood 1, 2, or 3 m away from participants. Participants performed a visual matching task to report the perceived distance. Results showed that facial expression influenced distance estimation, with faces exhibiting threatening or safe expressions judged closer than those showing neutral expressions. Females’ judgments were more likely to be influenced; but these influences largely disappeared beyond the 2 m distance. These results suggest that facial expressions of emotion (particularly threatening or safe emotions) influence others’ (especially females’) distance estimations but only within close proximity.

Facial emotion perception by intensity in children and adolescents with 22q11.2 deletion syndrome.

Difficulties in the recognition of emotions in expressive faces have been reported in people with 22q11.2 deletion syndrome (22q11.2DS). However, while low-intensity expressive faces are frequent in everyday life, nothing is known about their ability to perceive facial emotions depending on the intensity of expression. Through a visual matching task, children and adolescents with 22q11.2DS as well as gender- and age-matched healthy participants were asked to categorise the emotion of a target face among six possible expressions. Static pictures of morphs between neutrality and expressions were used to parametrically manipulate the intensity of the target face. In comparison to healthy controls, results showed higher perception thresholds (i.e. a more intense expression is needed to perceive the emotion) and lower accuracy for the most expressive faces indicating reduced categorisation abilities in the 22q11.2DS group. The number of intrusions (i.e. each time an emotion is perceived as another one) and a more gradual perception performance indicated smooth boundaries between emotional categories. Correlational analyses with neuropsychological and clinical measures suggested that reduced visual skills may be associated with impaired categorisation of facial emotions. Overall, the present study indicates greater difficulties for children and adolescents with 22q11.2DS to perceive an emotion in low-intensity expressive faces. This disability is subtended by emotional categories that are not sharply organised. It also suggests that these difficulties may be associated with impaired visual cognition, a hallmark of the cognitive deficits observed in the syndrome. These data yield promising tracks for future experimental and clinical investigations.

Young Children's Perception of Diagrammatic Representations

Diagrams and pictorial representations are common in children's lives and require abstraction away from visual perception. In three experiments, we investigated 4- to 8-year-olds’ comprehension of such representations. In Experiment 1 (N = 80), children were shown photographs of geometric objects and asked to choose the corresponding line drawing from among sets of four, or vice versa. Results showed considerable developmental progression, especially around age 6. Experiment 2 (N = 16) ruled out that 4-year-olds’ difficulties were due to problems with the visual matching task itself. Experiment 3 (N = 32) showed comparable performance for matching diagrams to 3D objects rather than to photographs. Findings suggest increasing understanding of diagrammatic representations around the time of school entry.

Objects exhibit body model like shape distortions.

Accurate knowledge about size and shape of the body derived from somatosensation is important to locate one’s own body in space. The internal representation of these body metrics (body model) has been assessed by contrasting the distortions of participants’ body estimates across two types of tasks (localization task vs. template matching task). Here, we examined to which extent this contrast is linked to the human body. We compared participants’ shape estimates of their own hand and non-corporeal objects (rake, post-it pad, CD-box) between a localization task and a template matching task. While most items were perceived accurately in the visual template matching task, they appeared to be distorted in the localization task. All items’ distortions were characterized by larger length underestimation compared to width. This pattern of distortion was maintained across orientation for the rake item only, suggesting that the biases measured on the rake were bound to an item-centric reference frame. This was previously assumed to be the case only for the hand. Although similar results can be found between non-corporeal items and the hand, the hand appears significantly more distorted than other items in the localization task. Therefore, we conclude that the magnitude of the distortions measured in the localization task is specific to the hand. Our results are in line with the idea that the localization task for the hand measures contributions of both an implicit body model that is not utilized in landmark localization with objects and other factors that are common to objects and the hand.Electronic supplementary materialThe online version of this article (doi:10.1007/s00221-015-4221-0) contains supplementary material, which is available to authorized users.

45. A novel cognitive fMRI task to assess brain mechanisms underlying visual processing and attention

Introduction Visual processing and attentional deficits can be found in early Alzheimer's disease (AD). Study objectives We aimed at developing a visual cognitive task to study brain mechanisms underlying visual processing in early AD using functional MRI (fMRI). To achieve our goal we developed a novel visual object matching task using conventional and unconventional (spatially rotated) views of object pairs. Here we present the fMRI results of a pilot study performed in healthy subjects (HS). Methods Twenty-two right-handed HS (11 men; age 25.3±2.8years) performed a cognitive task in a 1.5T MR scanner. The task consisted of 60 pairs of emotionally neutral images and 30 pairs of dots with a symbol placed on the right or left side (a control task). Participants viewed successive paired images, separated by a visual mask. The second image of each pair was either: same (identical) as the first image (canonical condition 1); different in identity (canonical condition 2); same as the first image but spatially rotated (unconventional condition 3); different in identity and spatially rotated (unconventional condition 4) (Schendan and Stern, 2008). Participants were instructed to respond as quickly as possible by pressing a YES (left) button if the second object of the paired images was the same as the first object (regardless of spatial orientation) or by pressing NO (right) button if they were different. In the control task participants responded with buttons depending on the side of a dot symbol placement. fMRI data were processed using SPM8 and the standard pipeline. The significance level was set to p Results At the group level, we found major activation of bilateral temporo-occipital areas, precuneus and inferior frontal gyri during the canonical conditions as compared to the control task. The unconventional conditions revealed additional activation of the posterior parietal areas including the superior parietal lobule and intraparietal sulcus as compared to the canonical conditions. Conclusion In the visual object matching task with conventional views of objects we observed major engagement of the ventral visual pathway. The task with spatially unconventional views of objects revealed additional recruitment of the dorsal visual pathway and the dorsal attentional network which is involved in the top-down attentional control of visual processing (Vincent et al., 2008). Our fMRI paradigm shows promise for assessing task-dependent attentional modulation of visual processing in early AD.

An ERP study of the relationship between anticipation, executive control and performance monitoring under interference condition in children with attention-deficit/hyperactivity disorder

The objective of the study was to compare visual sequential processing in school-age children with cochlear implants (CIs) and their normal-hearing (NH) peers. Visual sequential processing was examined using both behavioral and an event-related potential (ERP) measures.Eighteen children with CIs and nineteen children who had hearing within normal limits (NH) participated in the behavioral study. Subtests from the Test of Visual Perceptual Skills and the Sensory Integration and Praxis Test were administered to all children. ERP measures were collected from five children with CI and five age-matched peers. Peak latencies (N200 and P300) and reaction times for visual sequential processing were compared in these two groups.The findings of the study revealed significant group differences in visual sequential memory and visuo-motor sequencing tasks suggesting that children with severe-profound hearing loss may have difficulties in visual sequential tasks. The study also revealed longer P300 latencies and longer reaction times for a visual sequential matching task in children with CI when compared to their NH peers suggesting slower or delayed processing of visual sequential stimuli.This exploratory study involving behavioral and ERP measures showed that as a group, children with prelingual, severe-profound hearing loss who use CIs have difficulties with visual sequential processing. These findings may have implications for rehabilitation for children with hearing loss in the light of recent evidence that accurate and efficient processing of sequentially presented visual stimuli is important for language and reading outcomes.

Intranasal oxytocin enhances socially-reinforced learning in rhesus monkeys

There are currently no drugs approved for the treatment of social deficits associated with autism spectrum disorders (ASD). One hypothesis for these deficits is that individuals with ASD lack the motivation to attend to social cues because those cues are not implicitly rewarding. Therefore, any drug that could enhance the rewarding quality of social stimuli could have a profound impact on the treatment of ASD, and other social disorders. Oxytocin (OT) is a neuropeptide that has been effective in enhancing social cognition and social reward in humans. The present study examined the ability of OT to selectively enhance learning after social compared to nonsocial reward in rhesus monkeys, an important species for modeling the neurobiology of social behavior in humans. Monkeys were required to learn an implicit visual matching task after receiving either intranasal (IN) OT or Placebo (saline). Correct trials were rewarded with the presentation of positive and negative social (play faces/threat faces) or nonsocial (banana/cage locks) stimuli, plus food. Incorrect trials were not rewarded. Results demonstrated a strong effect of socially-reinforced learning, monkeys’ performed significantly better when reinforced with social versus nonsocial stimuli. Additionally, socially-reinforced learning was significantly better and occurred faster after IN-OT compared to placebo treatment. Performance in the IN-OT, but not Placebo, condition was also significantly better when the reinforcement stimuli were emotionally positive compared to negative facial expressions. These data support the hypothesis that OT may function to enhance prosocial behavior in primates by increasing the rewarding quality of emotionally positive, social compared to emotionally negative or nonsocial images. These data also support the use of the rhesus monkey as a model for exploring the neurobiological basis of social behavior and its impairment.

Observed manipulation enhances left fronto-parietal activations in the processing of unfamiliar tools.

Tools represent a special class of objects, as functional details of tools can afford certain actions. In addition, information gained via prior experience with tools can be accessed on a semantic level, providing a basis for meaningful object interactions. Conceptual representations of tools also encompass knowledge about tool manipulation which can be acquired via direct (active manipulation) or indirect (observation of others manipulating objects) motor experience. The present study aimed to explore the impact of observation of manipulation on the neural processing of previously unfamiliar, manipulable objects. Brain activity was assessed by means of functional magnetic resonance imaging while participants accomplished a visual matching task involving pictures of the novel objects before and after they received object-related training. Three training session in which subjects observed an experimenter manipulating one set of objects and visually explored another set of objects were used to make subjects familiar with the tools and to allow the formation of new tool representations. A control object set was not part of the training. Training-related brain activation increases were found for observed manipulation objects compared to not trained objects in a left-hemispheric network consisting of inferior frontal gyrus (iFG) pars opercularis and triangularis and supramarginal/angular gyrus. This illustrates that direct manipulation experience is not required to elicit tool-associated activation changes in the action system. While the iFG activation might indicate a close relationship between the areas involved in tool representation and those involved in observational knowledge acquisition, the parietal activation is discussed in terms of non-semantic effects of object affordances and hand-tool spatial relationships.

A cross-linguistic evaluation of script-specific effects on fMRI lateralization in late second language readers.

Behavioral and neuroimaging studies have provided evidence that reading is strongly left lateralized, and the degree of this pattern of functional lateralization can be indicative of reading competence. However, it remains unclear whether functional lateralization differs between the first (L1) and second (L2) languages in bilingual L2 readers. This question is particularly important when the particular script, or orthography, learned by the L2 readers is markedly different from their L1 script. In this study, we quantified functional lateralization in brain regions involved in visual word recognition for participants' L1 and L2 scripts, with a particular focus on the effects of L1–L2 script differences in the visual complexity and orthographic depth of the script. Two different groups of late L2 learners participated in an fMRI experiment using a visual one-back matching task: L1 readers of Japanese who learnt to read alphabetic English and L1 readers of English who learnt to read both Japanese syllabic Kana and logographic Kanji. The results showed weaker leftward lateralization in the posterior lateral occipital complex (pLOC) for logographic Kanji compared with syllabic and alphabetic scripts in both L1 and L2 readers of Kanji. When both L1 and L2 scripts were non-logographic, where symbols are mapped onto sounds, functional lateralization did not significantly differ between L1 and L2 scripts in any region, in any group. Our findings indicate that weaker leftward lateralization for logographic reading reflects greater requirement of the right hemisphere for processing visually complex logographic Kanji symbols, irrespective of whether Kanji is the readers' L1 or L2, rather than characterizing additional cognitive efforts of L2 readers. Finally, brain-behavior analysis revealed that functional lateralization for L2 visual word processing predicted L2 reading competency.