A functional near-infrared spectroscopy study of sustained attention to local and global target features

Despite a long history of vigilance research, the role of global and local feature discrimination in vigilance tasks has been relatively neglected. In this experiment participants performed a sustained attention task requiring either global or local shape stimuli discrimination. Reaction time to local feature discriminations was characterized by a quadratic trend over time-on-task with performance levels returning to initial levels late in the task. This trend did not occur in the global shape discrimination task. Functional near-infrared spectroscopy (fNIRS) was utilized in this study as an index of cerebral activation. In both tasks there was increased right hemisphere relative to left hemisphere oxygenation and right hemisphere oxygenation increased with time-on-task. Left hemisphere oxygenation, however, decreased slightly in the global task, but increased significantly in the local task as task duration increased. Indeed, total oxygenation, averaging both right and left, increased more with time-on-task in the local discrimination task. Both the performance and physiological results of this study indicate increased utilization of bilateral cerebral resources with time-on-task in the local, but not the global discrimination vigil.     

Performance of children with attention deficit hyperactivity disorder (ADHD) on a test battery of impulsiveness.

Children with ADHD were compared to healthy controls on a task battery of cognitive control, measuring motor inhibition (Go/No-Go and Stop tasks), cognitive inhibition (motor Stroop and Switch tasks), sustained attention and time discrimination. Children with ADHD showed an inconsistent and premature response style across all 6 tasks. In addition they showed task-specific impairments in measures of sustained attention, time discrimination, and motor inhibition, but spared cognitive inhibition. Measures of impairment correlated with behavioral hyperactivity and with each other, suggesting that they measure interrelated aspects of a multifaceted construct of cognitive impulsiveness. The task battery as a whole showed 76% correct discrimination of cases and controls.     

Time Perception: Modality and Duration Effects in Attention-Deficit/Hyperactivity Disorder (ADHD)

Time perception performance was systematically investigated in adolescents with and without attention-deficit/hyperactivity disorder (ADHD). Specifically, the effects of manipulating modality (auditory and visual) and length of duration (200 and 1000 ms) were examined. Forty-six adolescents with ADHD and 44 controls were administered four duration discrimination tasks and two control tasks, and a set of standardized measures. Participants with ADHD had higher thresholds than controls on all of the duration discrimination tasks, with the largest effect size obtained on the visual 1000 ms duration discrimination task. No group differences were observed on the control tasks. Visual–spatial memory was found to be a significant predictor of visual and auditory duration discrimination at longer intervals (1000 ms) in the ADHD sample, whereas auditory verbal working memory predicted auditory discrimination at longer intervals (1000 ms) in the control sample. These group differences suggest impairments in basic timing mechanisms in ADHD.     

Feasibility and validity of the structured attention module among economically disadvantaged preschool-age children

Rooted in the theory of attention put forth by Mirsky, Anthony, Duncan, Ahearn, and Kellam (1991), the Structured Attention Module (SAM) is a developmentally sensitive, computer-based performance task designed specifically to assess sustained selective attention among 3- to 6-year-old children. The current study addressed the feasibility and validity of the SAM among 64 economically disadvantaged preschool-age children (mean age = 58 months; 55% female); a population known to be at risk for attention problems and adverse math performance outcomes. Feasibility was demonstrated by high completion rates and strong associations between SAM performance and age. Principal Factor Analysis with rotation produced robust support for a three-factor model (Accuracy, Speed, and Endurance) of SAM performance, which largely corresponded with existing theorized models of selective and sustained attention. Construct validity was evidenced by positive correlations between SAM Composite scores and all three SAM factors and IQ, and between SAM Accuracy and sequential memory. Value-added predictive validity was not confirmed through main effects of SAM on math performance above and beyond age and IQ; however, significant interactions by child sex were observed: Accuracy and Endurance both interacted with child sex to predict math performance. In both cases, the SAM factors predicted math performance more strongly for girls than for boys. There were no overall sex differences in SAM performance. In sum, the current findings suggest that interindividual variation in sustained selective attention, and potentially other aspects of attention and executive function, among young, high-risk children can be captured validly with developmentally sensitive measures.     

Actively open-minded thinking: development of a shortened scale and disentangling attitudes towards knowledge and people

Actively open-minded thinking (AOT) is often used as a proxy for reflective thinking in research on reasoning and related fields. It is associated with less biased reasoning in many types of tasks. However, few studies have examined its psychometric properties and criterion validity. We developed a shortened, 17-item version of the AOT for quicker administration. AOT17 is highly correlated with the original 41-item scale and has highly similar relationships to other thinking dispositions, social competence and supernatural beliefs. Our analyses revealed that the AOT is not a unitary construct, but comprises four distinct dimensions, some of which concern attitudes towards knowledge, and others concern attitudes towards people. This factor structure was replicated in another data-set, and correlations with other measures in four data-sets (total N = 3345) support the criterion validity of these dimensions. Different dimensions were responsible for the AOT's relationships with other thinking dispositions.     

Examining the relationship between skilled music training and attention

While many aspects of cognition have been investigated in relation to skilled music training, surprisingly little work has examined the connection between music training and attentional abilities. The present study investigated the performance of skilled musicians on cognitively demanding sustained attention tasks, measuring both temporal and visual discrimination over a prolonged duration. Participants with extensive formal music training were found to have superior performance on a temporal discrimination task, but not a visual discrimination task, compared to participants with no music training. In addition, no differences were found between groups in vigilance decrement in either type of task. Although no differences were evident in vigilance per se, the results indicate that performance in an attention-demanding temporal discrimination task was superior in individuals with extensive music training. We speculate that this basic cognitive ability may contribute to advantages that musicians show in other cognitive measures.     

Aggression in boys with attention deficit-hyperactivity disorder: Methylphenidate effects on naturalistically observed aggression,response to provocation,and social information processing

High and low-aggressive boys with attention deficit-hyperactivity disorder (ADHD) were compared and the effects of methylphenidate were examined on measures from three domains of aggression: (1) directly observed verbal and nonverbal aggressive behaviors exhibited in the context of a day treatment program, (2) aggressive responding when provoked during a laboratory task, and (3) social information processing patterns exhibited on tasks designed to tap the putative cognitive components of aggression. The high-aggressive (HA) and low-aggressive (LA) subgroups differed significantly on observational measures of aggression and on the laboratory provocation task, but the HA group showed more deviant cognitions on only one of the numerous measures of social information processing. Regarding medication effects on the direct observation measures, methylphenidate decreased aggression for both subgroups. On the laboratory provocation task, methylphenidate had only minimal effects. Significant drug effects were obtained on only two recall social information processing measures.     

Further explorations of perceptual speed abilities in the context of assessment methods, cognitive abilities, and individual differences during skill acquisition

Measures of perceptual speed ability have been shown to be an important part of assessment batteries for predicting performance on tasks and jobs that require a high level of speed and accuracy. However, traditional measures of perceptual speed ability sometimes have limited cost-effectiveness because of the requirements for administration and scoring of paper-and-pencil tests. There have also been concerns about the validity of previous computer approaches to administering perceptual speed tests (e.g., see Mead & Drasgow, 1993). The authors developed two sets of computerized perceptual speed tests, with touch-sensitive monitors, that were designed to parallel several paper-and-pencil tests. The reliability and validity of the tests were explored across three empirical studies (N = 167, 160, and 117, respectively). The final study included two criterion tasks with 4.67 and 10 hours of time-on-task practice, respectively. Results indicated that these new measures provide both high levels of reliability and substantial validity for performance on the two skill-learning tasks. Implications for research and application for computerized perceptual speed tests are discussed.     

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.     

Controlled Social Interaction Tasks to Measure Self-Perceptions: No Evidence of Positive Illusions in Boys with ADHD

Studies have suggested that children with Attention-Deficit/Hyperactivity Disorder (ADHD) possess a Positive Illusory Bias (PIB) where they have higher self-perceptions of competence than more objective measures of their competence. However, recent research calls into question the primary methodology of these studies, that is, difference scores. This study investigated the PIB in boys with ADHD within the social domain using a novel methodology that refrains from using difference scores. Eighty-one 8- to 12-year-old boys with and without ADHD completed social interaction tasks where their actual social performance was made comparable, allowing for tests of between-group differences in self-perceptions that do not rely on difference scores. In addition, to examine whether clarity of social feedback moderates the presence of the PIB, the social tasks presented unclear, clear positive, or clear negative feedback. Boys rated how well they performed in each social interaction task, and these ratings were compared between ADHD and non-ADHD groups. Compared to the non-ADHD group, boys with ADHD did not show a PIB in their ratings of performance on the social tasks. There also was no moderation of boys’ ratings by type of feedback received. In contrast, when the PIB was calculated using difference scores based on child and parent ratings of child competence, boys with ADHD showed a PIB compared to boys without ADHD. These findings call attention to the need to re-examine the phenomenon of the PIB using methodologies outside of difference scores.     

Convergent validity of and bias in maternal reports of child emotion

This study examined the convergent validity of maternal reports of child emotion in a sample of 190 children between the ages of 3 and 6. Children completed a battery of 10 emotion-eliciting laboratory tasks; their mothers and untrained na?ve observers rated child emotions (happiness, surprise, fear, sadness, and anger) following each task, and trained coders rated videotapes of each task for the same emotions. Consistent with studies using other designs, maternal reports demonstrated weak to moderate convergence with the other rating methods. Extending prior research, a number of maternal characteristics (particularly lifetime psychiatric diagnoses and personality traits) were associated with their reports of child emotions in the lab, above and beyond the effects of objective coding and observer reports of child emotions. For some emotions, mothers' mental health and dispositional variables were more strongly related to their reports of the child's emotions than were objective indices of the child's observable emotional behavior.     

Time reproduction, working memory, and behavioral inhibition in children with ADHD.

Barkley (1997a) proposed that the central deficit in Attention Deficit Hyperactivity Disorder (ADHD) is in behavioral inhibition, resulting in deficits both in working memory and sense of time. To test this theory, 21 children with ADHD and a matched sample (ages 6-13) completed a variety of tasks that measured behavioral inhibition, working memory, attention, and time reproduction. Children with ADHD performed significantly below controls on measures of inhibition, attention, and time reproduction. They did not differ significantly from controls, however, on tasks of working memory. In addition, performance on the working memory tasks was not correlated with the time reproduction task. We discuss the relevance of these results in the context of current theories of ADHD.     

Perception of speech and nonspeech stimuli by children with and without reading disability and attention deficit hyperactivity disorder

The auditory temporal deficit hypothesis predicts that children with reading disability (RD) will exhibit deficits in the perception of speech and nonspeech acoustic stimuli in discrimination and temporal ordering tasks when the interstimulus interval (ISI) is short. Initial studies testing this hypothesis did not account for the potential presence of attention deficit hyperactivity disorder (ADHD). Temporal order judgment and discrimination tasks were administered to children with (1) RD/no-ADHD (n=38), (2) ADHD (n=29), (3) RD and ADHD (RD/ADHD; n=32), and (4) no impairment (NI; n=43). Contrary to predictions, children with RD showed no specific sensitivity to ISI and performed worse relative to children without RD on speech but not nonspeech tasks. Relationships between perceptual tasks and phonological processing measures were stronger and more consistent for speech than nonspeech stimuli. These results were independent of the presence of ADHD and suggest that children with RD have a deficit in phoneme perception that correlates with reading and phonological processing ability. (c) 2002 Elsevier Science (USA).     

The ecological validity of laboratory and analogue assessment methods of ADHD symptoms

An important question in the attempt to generalize laboratory findings on attention deficit-hyperactivity disorder (ADHD) children to clinical issues concerning their assessment, diagnosis, outcome, and treatment response is the ecological validity of the commonly used tasks and analogue behavioral observation procedures. This paper examines the concept of ecological validity and issues inherent in its evaluation. The evidence from a variety of sources is then reviewed on the relationship between laboratory methods of assessing inattention, impulsivity, and overactivity and measures of these same constructs in natural settings. Additional findings pertaining to this issue from a recent study of 140 ADHD and normal children and 159 ADHD and normal adolescents using a multimethod battery of tests are also reported. In general, the ecological validity of most methods is of a low to moderate degree, with some traditional laboratory tasks proving unsatisfactory. A few tasks demonstrated acceptable degrees of ecological validity but even these require improvement. It is concluded that future advances in ecological validity are likely to come from: (a) a greater reliance on assessments of the target behaviors in natural settings and (b) combining several of the more promising tasks and analogue methods into a battery that is taken over longer time intervals than has been customary and averaged across repeated administrations.An earlier version of this paper was presented at the International Symposium on Attention Deficit Hyperactivity Disorder, Amsterdam, The Netherlands, April 6 and 7, 1989. The author wishes to thank Charles E. Cunningham, Ph.D., Susan Campbell, Ph.D., Mark Rapport, Ph.D., Eric Mash, Ph.D., and Herbert Quay, Ph.D., for their comments on an earlier version of this paper, and to Marcel Kinsbourne, M.D., for his comments on the presentation itself. The author was supported by funds from NIMH grants 41464, 41583, and 42181 during the preparation of this review.     

Quokkas (Setonix brachyurus) demonstrate tactile discrimination learning and serial-reversal learning

Two male quokkas (Setonix brachyurus: a herbivorous macropod marsupial) were trained to discriminate pairs of stimuli in the laboratory. Quokkas indicated their choice by pulling on 1 of 2 simultaneously presented cords. The quokkas' discrimination abilities were tested on 6 tactile and 6 visual discrimination tasks. Correct responses were rewarded with food. For both quokkas, all tactile tasks were learned to a criterion of 75% correct in up to 4 20-trial sessions. No visual task maintained criterion performance in 4 sessions. One tactile discrimination was reversed 10 times. After the 1st reversal, the error rate declined sharply and fell to a level well below the initial discrimination.     

Separating automatic and intentional inhibitory mechanisms of attention in adults with attention-deficit/hyperactivity disorder

Researchers in the cognitive sciences recognize a fundamental distinction between automatic and intentional mechanisms of inhibitory control. The use of eye-tracking tasks to assess selective attention has led to a better understanding of this distinction in specific populations, such as children with attention-deficit/hyperactivity disorder (ADHD). This study examined automatic and intentional inhibitory control mechanisms in adults with ADHD using a saccadic interference task and a delayed ocular response task. Thirty adults with ADHD were evaluated against 27 comparison adults on measures of inhibitory control. The delayed ocular response task showed that adults with ADHD were less able than comparison adults to inhibit a reflexive saccade toward the sudden appearance of a stimulus in the periphery. However, saccadic interference task performance showed that the ADHD group did not differ significantly from the comparison group on a measure of automatic inhibitory control. These findings suggest a dissociation between automatic and intentional inhibitory deficits in adults with ADHD.     

Neurocognitive performance of 5- and 6-year-old children who met criteria for attention deficit/hyperactivity disorder at 18 months follow-up: results from a prospective population study

The aim of this prospective study was to examine whether neurocognitive performance of children aged 5–6 years distinguished children who were later diagnosed with attention deficit/hyperactivity disorder (ADHD) or borderline ADHD from children without ADHD after adjustment for behavioral measures and to examine the influence of comorbid psychopathology. Out of a general population of 1,317 children, 366 children were selected on the basis of their scores on the Child Behavior Checklist (CBCL). Eighteen months later, the parents were interviewed using a standardized child psychiatric interview: 33 children were classified as ADHD and 75 children as borderline ADHD, and there were 258 children without ADHD. Children with rated ADHD were significantly impaired on measures of visuomotor ability and working memory compared to children without ADHD after adjustment for CBCL results. The performance of borderline ADHD children was in between that of children with and without ADHD. In addition, 4 groups of children were analyzed: 9 ADHD, 24 ADHD with comorbid oppositional defiant disorder/conduct disorder (ODD/CD), 59 ODD/CD, and 274 controls. Children with rated comorbid ADHD and ODD/CD performed significantly worse on these tasks compared to children with rated ODD/CD and control children while they did not differ from ADHD children. Our results imply that neurocognitive measures can contribute to the early identification of ADHD with and without comorbid ODD/CD.     

Response Style Differences in the Inattentive and Combined Subtypes of Attention-Deficit/Hyperactivity Disorder

This study examined potential differences between the inattentive and combined ADHD subtypes using laboratory tasks assessing behavioral inhibitory processes. Seventy-five children completed two tasks of behavioral inhibition believed to isolate different processes: the cued reaction time task (CRT), a basic inhibition task, and the go/no-go task (GNG), a complex inhibition task that incorporates motivational contingencies. Three groups of participants were identified, including ADHD/Inattentive (n = 17), ADHD/Combined (n = 37), and comparison (n = 21). Results indicated that rather than showing behavioral inhibition deficits, the ADHD/I children appeared overly inhibited, as evidenced by slower reaction times across the two tasks and significantly higher errors of omission in the GNG task. Additionally, the ADHD/I children did not demonstrate cue dependency effects on the CRT task, suggesting that they were failing to incorporate relevant information before making a response. The sluggish and inhibited performance of the ADHD/I group challenges the idea that it is a subtype of ADHD.     

Parenting in mothers with and without attention-deficit/hyperactivity disorder

The authors examined the impact of maternal attention-deficit/hyperactivity disorder (ADHD) on parenting behaviors. Sixty mothers between the ages of 31 and 50 with (n = 30) and without (n = 30) ADHD and their 8- to 14-year-old children with ADHD completed self-report and laboratory measures of monitoring of child behavior, consistency in parenting, and parenting problem-solving abilities. These parenting behaviors were selected because of their established links to the development of child behavior problems. As predicted, mothers with ADHD were found to be poorer at monitoring child behavior and less consistent disciplinarians compared with mothers without ADHD. There was some evidence to support the prediction that mothers with ADHD were less effective at problem solving about childrearing issues than control mothers. The differences between the 2 groups of mothers persisted after child oppositional and conduct-disordered behavior were controlled. These results indicate that parenting is an area of functioning that requires more attention in adult ADHD research.     

Accuracy of drawing in a dual-task and resistance-to-distraction study: motor or attention deficit?

To determine whether manual incoordination is caused by attention deficit or not, we used an accuracy drawing task as a primary task in dual-task and resistance-to-distraction studies, and examined if thus measured attention could differentiate inattention (IA) and combined (CO) subtypes of ADHD. The secondary tasks and distractions failed to lower the primary task performance in IA, CO and control groups. We also compared the impairment scores of the accuracy drawing tasks from the Movement Assessment Battery for Children [Henderson, S. E., & Sugden, D. A. (1992). Movement assessment battery for children. London: Psychological Corporation.] between the groups with attention deficit hyperactivity disorder (ADHD) and/or developmental coordination disorder-inaccurate drawing type (DCD-ID). There were no group differences in the impairment score between the control and the ADHD groups, and between ADHD and ADHD plus DCD-ID groups. We concluded that inaccurate drawing is not caused by attention deficit, but that it is a manifestation of a motor deficit as a separate entity from attention deficit.