Ophthalmic disorder may affect visuo-attentional performance in childhood

The aim of this study was to explore the visuo-attentional skills of children with an ophthalmic disorder. Twenty-four patients and 60 healthy controls between the ages 4 and 7 years, all right-handed with normal or corrected-to-normal close visual acuity, were divided into four age groups. Patients' diagnoses included refractive disorders (e.g., myopia, hypermetropia), strabismus, amblyopia, cataract, and nystagmus. All participants performed nine paper-and-pencil visuospatial tasks aiming to assess selective attention (cancellation tasks), spatial working memory (symbol orientation task), fine visual analysis (embedded figures test), and simple perceptual analysis (shape-matching task). In healthy children, the results showed that performance on all visuo-attentional tasks improved with age. While perception, orientation of attention, and visual working memory develop by the time children begin school (age 5), more sophisticated abilities such as attention disengagement and motor control continue to develop during late childhood. Moreover, a spatial bias in attention orienting appeared with reading acquisition (6–7 years). In ophthalmic children, at 4 years of age defects were observed in all assessed functions, but at 7 years an attentional deficit was virtually the only one remaining. Overall, the results demonstrate that children with an ophthalmologic disorder may experience difficulties with visuospatial tasks despite corrected-to-normal visual acuity.     

Temporal performance in 4-8 year old children. The effect of chronometric information in task execution

The present study explores temporal performance in children between 4 and 11 years of age. In order to optimise the children's performance, verbal instructions and demonstrations were used to specify the temporal requirement of the task. Moreover, specific feedback was given, which indicated the success of a response, or, in case of a mistake, indicated the type of error made. The task was presented in two phases: training and experimental. In the first phase, the child practised until a learning criterion was reached. In the experimental phase, four conditions were defined according to the information provided to the children. In general, the results of the training phase showed an improvement in performance with advancing age. Significant differences were found in children between 7 and 8 years of age, which points to an important transition period. Results of the experimental phase showed a pronounced impact of instructions on the performance of the task and on the strategies used to control timing behaviour. Specifically, the instructions that contained chronometric information caused an impairment in task performance and a change in the strategy used.     

Visual perspective taking impairment in children with autistic spectrum disorder

Evidence from typical development and neuroimaging studies suggests that level 2 visual perspective taking - the knowledge that different people may see the same thing differently at the same time - is a mentalising task. Thus, we would expect children with autism, who fail typical mentalising tasks like false belief, to perform poorly on level 2 visual perspective taking as well. However, prior data on this issue are inconclusive. We re-examined this question, testing a group of 23 young autistic children, aged around 8 years with a verbal mental age of around 4 years and three groups of typical children (n = 60) ranging in age from 4 to 8 years on a level 2 visual perspective task and a closely matched mental rotation task. The results demonstrate that autistic children have difficulty with visual perspective taking compared to a task requiring mental rotation, relative to typical children. Furthermore, performance on the level 2 visual perspective taking task correlated with theory of mind performance. These findings resolve discrepancies in previous studies of visual perspective taking in autism, and demonstrate that level 2 visual perspective taking is a mentalising task.     

Assessing tactile perception: effects of different visual barriers on performance

Blindfolding candidates when testing their tactile performance may increase their anxiety. This study examined whether different visual barriers would influence tactile performance on timed tasks. It was hypothesised that candidates using a blindfold would be more anxious, but that they would benefit by the potentially positive effects of arousal on performance and not differ from candidates using a screen to limit visual access to task material. 200 participants (ages 19 to 30 years), randomly assigned to the two conditions, completed a tactile perception task, as well as an anxiety scale. In contrast to the expected outcome, the screen sample took significantly longer to complete the task. This was hypothesised to be the result of increased distraction given competing cross-modal attentional demands and the consequent visual and tactile attention switching. Practitioners may need to consider the influences of visual interference when assessing tactile performance.     

Virtual-reality-based attention assessment of ADHD: ClinicaVR: Classroom-CPT versus a traditional continuous performance test

Virtual-reality-based assessment may be a good alternative to classical or computerized neuropsychological assessment due to increased ecological validity. ClinicaVR: Classroom-CPT (VC) is a neuropsychological test embedded in virtual reality that is designed to assess attention deficits in children with attention deficit hyperactivity disorder (ADHD) or other conditions associated with impaired attention. The present study aimed to (1) investigate the diagnostic validity of VC in comparison to a traditional continuous performance test (CPT), (2) explore the task difficulty of VC, (3) address the effect of distractors on the performance of ADHD participants and typically-developing (TD) controls, and (4) compare the two measures on cognitive absorption. A total of 33 children diagnosed with ADHD and 42 TD children, aged between 7 and 13 years, participated in the study and were tested with a traditional CPT or with VC, along with several cognitive measures and an adapted version of the Cognitive Absorption Scale. A mixed multivariate analysis of covariance (MANCOVA) revealed that the children with ADHD performed worse on correct responses had more commissions and omissions errors than the TD children, as well as slower target reaction times . The results showed significant differences between performance in the virtual environment and the traditional computerized one, with longer reaction times in virtual reality. The data analysis highlighted the negative influence of auditory distractors on attention performance in the case of the children with ADHD, but not for the TD children. Finally, the two measures did not differ on the cognitive absorption perceived by the children.     

Age trends in children's time-sharing performance

To investigate developmental differences in time-sharing performance, 60 boys, 20 in each of three age groups (7-, 10-, and 13-year-olds) performed an auditory matching task and a tracking task alone and concurrently, the latter under two sets of instructions. Decrements produced by concurrent performance were compared for the three age groups. When the time-shared tasks were presented as equally important, time-sharing produced significantly greater proportional decrements in the tracking performance of the younger children and for all age groups tracking task decrements were directly related to matching task difficulty. Subsequently, the children were instructed that one or the other of the tasks was more important and that they were to improve their performance on that task. All three age groups showed a significant improvement on the task emphasized by instructions. The relationship of the results to two models of information processing is discussed.     

Relationship between hemispatial inattention and performance of activities of daily living in patients with schizophrenia

This study investigated the relation of hemispatial inattention to the performance of daily functions in 32 patients with schizophrenia or schizoaffective disorder and in 31 healthy controls. They were tested on the relationship between a target cancellation task and the Activities of Daily Living Rating Scale-II (ADLRS-II). According to the results of the hemispatial inattention test, the patients with schizophrenia made more omissions in the cancellation test than the controls. In addition, the results showed a significant correlation between number of omissions on the cancellation test and the ADLRS-II score in the study participants. A statistically significant relationship was observed between hemispatial inattention and the functional status of patients with schizophrenia, and suggests the need to incorporate measures of visual attention into psychiatric rehabilitation assessments.     

Competence and performance factors in word order awareness and early reading

Previous research has yielded contradictory estimates of the age at which children develop word order awareness, yet has shown that word order awareness predicts beginning reading. In Study 1, forty-five 6-year-olds and forty-three 5-year-olds were given a word order awareness task which used three different sets of instructions, increasing in explicitness. Five months later, they were given the word order task, along with vocabulary, reading readiness (for the 5-year-olds), or reading achievement tests. In Study 2, eighty-nine 6-year-olds were twice given a word order task and a reading achievement test (3 months apart): and ninety-one 5-year-olds were given the word order task and a test of reading readiness. Most older children at Time 2 passed the word order task, whereas many of the younger children could not do so even with explicit instructions. Children who demonstrated word order awareness without explicit instructions were advanced in reading, vocabulary, and readiness. Children requiring further instructions to detect word order were average in reading ability, and those who completely lacked competence in word order awareness were below average in readiness and achievement. Word order awareness may be related to the spontaneous use of syntactic strategies in reading or to other types of linguistic awareness which are useful for beginning readers.     

AULA virtual reality test as an attention measure: Convergent validity with Conners’ Continuous Performance Test

The majority of neuropsychological tests used to evaluate attention processes in children lack ecological validity. The AULA Nesplora (AULA) is a continuous performance test, developed in a virtual setting, very similar to a school classroom. The aim of the present study is to analyze the convergent validity between the AULA and the Continuous Performance Test (CPT) of Conners. The AULA and CPT were administered correlatively to 57 children, aged 6–16 years (26.3% female) with average cognitive ability (IQ mean = 100.56, SD = 10.38) who had a diagnosis of attention deficit/hyperactivity disorder (ADHD) according to DSM-IV-TR criteria. Spearman correlations analyses were conducted among the different variables. Significant correlations were observed between both tests in all the analyzed variables (omissions, commissions, reaction time, and variability of reaction time), including for those measures of the AULA based on different sensorial modalities, presentation of distractors, and task paradigms. Hence, convergent validity between both tests was confirmed. Moreover, the AULA showed differences by gender and correlation to Perceptual Reasoning and Working Memory indexes of the WISC-IV, supporting the relevance of IQ measures in the understanding of cognitive performance in ADHD. In addition, the AULA (but not Conners’ CPT) was able to differentiate between ADHD children with and without pharmacological treatment for a wide range of measures related to inattention, impulsivity, processing speed, motor activity, and quality of attention focus. Additional measures and advantages of the AULA versus Conners’ CPT are discussed.     

A developmental study of visual attention: Issues of filtering efficiency and focus

A forced-choice reaction time (RT) task was used to assess developmental changes in filtering and the concomitant ability to narrow the focus of the attentional lens. Participants included 20 children in each of four age groups (4, 5, 7, and 9 years), as well as 20 adults between the ages of 21 and 29 years. Conditions varied with regard to the presence or absence of distractors and their proximity to a target stimulus, and the presence or absence of a visual window within which the target stimulus was presented. Age-related differences in the ability to filter task-irrelevant stimuli were found. The performance of 4-year-old children was adversely affected with the presence of distractors located at both 5.7° and 0.95° of visual angle from target stimuli, whereas that of children aged 5, 7, and 9 was negatively affected only with distractors 0.95° of visual angle from the target. Adults' performance was not adversely affected by the presence of distractors. Developmental differences in focusing attention were further highlighted by the finding that the presence of a visual window cue was only associated with faster RTs among 4-year-old children. These results are discussed in terms of the zoom-lens metaphor of visual attention, and the development of the ability to vary the size of an attentive zoom-lens in response to task requirements.     

Effects of attention state on electrodermal activity during auditory stimulation of children.

During passive and active listening tasks electrodermal activity of 49 healthy school children was studied. The procedure included baseline recording, a passive listening task, instructions, and simple and discriminative active-listening tasks. On the passive task from Trials 1 to 10, habituation of the amplitude of the skin conductance response (SCR) occurred. Habituation of SCR amplitude did not occur during the active tasks. The children seemed to pay more attention during the active tasks than during the passive task, since the need to press the key is apt to require and may even increase general attention. As for temporal variables of SCR, the frequency of spontaneous SCRs showed a significant negative correlation with SCR latency and rise time. Reaction time exhibited a significant negative correlation with age. An increase in reaction time was found during the discriminative active-listening task over that for the simple active-listening task during the course of 10 trials. The younger children (6-8 yr.) seemed to require longer to pay attention than the older ones (10-12 yr.). Children seemed to pay more attention during the discriminative than during the simple active-listening task, since the need to press the key for discrimination should require and is likely to increase general attention.     

Eye movements and a dynamic stimulus situation

Two experiments were conducted to investigate performance with and without voluntary eye movements in a dynamic stimulus situation. Experiment I used a combined tracking and prediction task. Level of training, complexity of the signal, and visual region sampled were the variables of interest. Experiment II manipulated the same variables in only the prediction task. Thus, the amount of attention allotted to the prediction task was varied between experiments. The d' measure indicated that under peripheral vision instructions accuracy on the prediction task was the same as under foveal vision instructions provided that: (1) the level of task complexity was low, (2) the subjects were well trained, and (3) only the prediction task was performed, or in the dual task situation only visual regions near the fovea were sampled. All other combinations of the variables resulted in a lower performance scores under peripheral vision instructions. Results are interpreted within the framework of current theories of the functional visual field.     

Executive functioning in preschool children: performance on A-not-B and other delayed response format tasks

The A-not-B (AB) task has been hypothesized to measure executive/frontal lobe function; however, the developmental and measurement characteristics of this task have not been investigated. Performances on AB and comparison tasks adapted from developmental and neuroscience literature was examined in 117 preschool children (ages 23-66 months). Age significantly predicted performance on AB, Delayed Alternation, Spatial Reversal, Color Reversal, and Self-Control tasks. A four-factor analytic model best fit task performance data. AB task indices loaded on two factors with measures from the Self-Control and Delayed Alternation tasks, respectively. AB indices did not load with those from the reversal tasks despite similarities in task administration and presumed cognitive demand (working memory). These results indicate that AB is sensitive to individual differences in age-related performance in preschool children and suggest that AB performance is related to both working memory and inhibition processes in this age range.     

Working memory abilities and children's performance in laboratory analogues of classroom activities

Laboratory analogues of classroom activities on which children with low working memory skills have been observed to perform very poorly were developed and employed in two studies. In Study 1, 5‐ and 6‐year‐old completed one task involving recalling spoken sentences and counting the numbers of words, and another task involving the identification of rhyming words in spoken poems. Poorer performance of low than average working memory children was obtained on the recall measure of both tasks. In Study 2, 5‐ and 6‐year‐old children heard spoken instructions involving the manipulation of a sequence of objects, and were asked either to perform the instructions or repeat them, in different conditions. The accuracy of performing but not repeating instructions was strongly associated with working memory skills. These results indicate that working memory plays a significant role in typical classroom activities that involve both the storage and mental manipulation of information. Copyright © 2007 John Wiley & Sons, Ltd.     

Effects of cooperative,competitive, and individualistic sets on performance in children's groups

Four instructional sets were employed in a study of task performance in triads of first- (age 7 years) and third-grade (age 9 years) children: promotive (equal rewards given to each participant for 12 trials); individualistic (rewards given in proportion to individual performance for 12 trials); contrient-promotive (winner take all for 6 trials followed by equal rewards for 6 trials); and contrient-individualistic (winner take all for 6 trials followed by proportional rewards for 6 trials). Performance under the promotive condition was superior to performance in the other conditions during the first half of the session. Promotive conditions improved performance during the second half of the session in triads that had received contrient instructions earlier but not to levels reached under continuous promotive conditions. Results are discussed in relation to theories of cooperation and competition.     

The effects of methylphenidate on various types of activity level and attention in hyperkinetic children

The effects of methylphenidate on a number of objective measures of activity level and attention were assessed on three repeated occasions in four types of settings: free play, movie viewing, testing, and restricted play periods. Subjects were 36 boys between 5 and 12 years of age and of average intelligence. Of these, 18 were diagnosed as hyperkinetic and participated in a double-blind drug-placebo crossover design. The remaining 18 boys, matched in age and IQ with the hyperkinetic children, served as a control group and received no drugs. Results indicated that compared to placebo, methylphenidate significantly reduced wrist, ankle, locomotor, and seat movement activity in the hyperkinetic children regardless of the type of setting in which the measures were taken. Relatively fewer significant drug effects were noted on the measures of concentration or attention. While concentration to reaction time, maze performance, and a movie viewing task improved during drug treatment, the length of attention to toys in free play was not significantly improved. Parental ratings of activity level were also improved by the drug. The hyperkinetic children were also observed to increase their level of task-irrelevant activity over time while control children remained relatively stable in activity over repeated assessment. Despite the positive drug effects, clinical observations suggested that methyl-phenidate may have reduced the interest of some children in their environment.     

A developmental study of timing behavior in 4 1/2- and 7-year-old children

The present study investigated effects of age and instructions on temporal regulations of behavior in children. In the first experiment 4 1/2-year-old and 7-year-old subjects were trained with a DRL (differential reinforcement of low rates) 5-s and a DRL 10-s schedule. Results demonstrate that age and timing performance are related. Seven-year-olds are more efficient than the 4 1/2-year-olds. A striking decline in the 4 1/2-year-old children's capacity to space responses was observed in the DRL 10-s schedule as compared to the DRL 5-s schedule. Analysis of individual performances suggests that the evolution of DRL performance between 4 and 7 years of age depends not only on the development of the capacity to delay responding but also on the acquisition of the ability to represent the reinforcement contingencies, that is, the temporal parameters of the task to oneself. In order to test this hypothesis a second experiment was conducted where instructions to wait between operant responses were given to a group of 4 1/2-year-old subjects at the beginning of a DRL 5-s and a DRL 10-s schedule. The results show that these instructions enhance DRL performance. By directing the 4 1/2-year-old subjects' attention to the temporal requirements of the task, instructions led to efficient performance and accurate timing of responses to the DRL schedule.     

The problem-solving strategies of kindergarten and first-grade children during discrimination learning

Kindergarten and first-grade children (6 and 7 years of age, respectively) were given specially designed discrimination tasks with introtact probes preceding each trial. One group (CON) was given the criterion task without prior training. A second group (LTL) received three pretraining tasks of the same type as the criterion task. A third group (HYP) received the same pretraining tasks, but with explicit instructions designed to teach a simple hypothesis-testing strategy. Several indices, designed to reflect the use of win-stay and lose-shift rules, as well as memory for disconfirmed hypotheses, were computed from the protocols of the criterion task. The indices for Group CON suggested that most of these children were using a guessing strategy that involved quite frequent changes in hypotheses. Moreover, many of these children restricted their hypotheses to the irrelevant cues. The indices for Group LTL revealed a spontaneous use of the hypothesis-testing strategy by nearly half of the children. The results for Group HYP indicated that over four-fifths of these children became highly efficient in the use of the problem-solving strategy.     

Development of unimanual versus bimanual task performance in an isometric task

Sixty-three children between 5 and 12 years of age and 15 adults performed a unimanual and a bimanual isometric force task. The performance of the preferred hand in the unimanual task was compared to the performance of the preferred hand in the bimanual task. It was hypothesized that in the bimanual task the absolute error will be higher, there will be more irregularity and the participants will need more time due to the additional effort from the central nervous system, especially with respect to the communication between the hemispheres. Furthermore, in younger children bimanual force variability was expected to be higher due to developmental aspects concerning callosal maturation and attention. It was found that with respect to force generation the preferred hand was not affected by bilateral isometric force generation, but with respect to force regulation it was. The coefficient of variation (CV) of the force was 34% larger in the bimanual task as compared to the unimanual task. For the time to target force, the increase was 28%. With repetition of the trials the CV decreased in the bimanual task, but only in the youngest age group. During development there was no change in absolute error, yet there was a major reduction in force variability in the bimanual task. It is suggested that improvement in interhemispheric communication and in the ability to focus attention plays a role in the decrease in variability with age.     

Attentional differences between groups of preschool children differentiated by teacher ratings of attention and hyperactivity

This study aimed to extend earlier work ( Wilding, Munir, & Cornish, 2001 ; Wilding, 2003 ) which showed that children (aged 6–15) who were rated by their teachers as having poor attentional ability made more errors on a visual search task than children rated as having good attentional ability. The present study used a simpler version of the search task which had previously been used to study attention in children with Fragile X syndrome ( Scerif, Cornish, Wilding, Driver, & Karmiloff‐Smith, 2004 ) and studied performance in normal children from a younger age group. Children aged 3 and 4 were rated by teachers for attention and hyperactivity. Regression analyses, with verbal mental age (VMA), chronological age (CA), and attention rating as independent variables, found that children with higher VMA made fewer false alarms in visual searches, as did children given a better attention rating. However, none of the independent variables was related to time or distance travelled for correct responses. The relation between attention rating and error rate was non‐linear, with the error rate increasing once the attention rating fell below the mean. The results are discussed in relation to explanations of poor attention in terms of weak inhibition.