The wide attentional window: a major deficit of children with attention difficulties

Implementation of an online spacing flanker task and evaluation of its test-retest reliability using measures of inhibitory control and the distribution of spatial attention

The flanker task (Eriksen & Eriksen, Perception & Psychophysics, 16(1), 143-149, 1974) has been highly influential and widely used in studies of visual attention. Its simplicity has made it popular to include it in experimental software packages and online platforms. The spacing flanker task (SFT), in which the distance between the target and flankers varies, is useful for studying the distribution of attention across space as well as inhibitory control. Use of the SFT requires that the viewing environment (e.g., stimulus size and viewing distance) be controlled, which is a challenge for online delivery. We implement and evaluate an online version of the SFT that includes two calibration pretests to provide the necessary control. Test-retest and split-half reliability of the online version was compared with a laboratory version on measures of inhibitory control and measures of the distribution of attention across space. Analyses show that the online SFT is comparable to laboratory testing on all measures. Results also identify two measures with good test-retest reliability that hold promise for studying performance in the SFT: the mean flanker effect (ICC = 0.745) and RTs on incongruent trials across distances (ICC = 0.65-0.71).

Is the deficit in attention-deficit/hyperactivity disorder a concentration deficit?

Attention-deficit/hyperactivity disorder (ADHD) is comprised of two behavioral clusters of symptoms, inattention and hyperactivity/impulsivity. Numerous studies have attempted to address the underlying neuropsychological mechanism of ADHD. However, there is still no uniform mechanism that can fully explain both inattention and hyperactivity/impulsivity symptoms. This review describes the research findings that have shifted the focus from cognitive selective attention to executive function deficits and notes that the prominence of the attention deficit remains unclear. As ADHD is not consistently explained by cognitive selective attention but rather with cognitive sustained attention/vigilance and executive function deficits, this review suggests that concentration deficit is likely the cause of inattention symptoms. Indeed, considering concentration deficit as the cause of inattention symptoms may better describe the underlying difficulties of maintaining and controlling attention in ADHD. In addition, as concentration, impulsivity, and hyperactivity may share a common cognitive deficit, this shift in focus may help in identifying a single mechanism for all ADHD symptoms.

Continuous effects of bilingualism and attention on Flanker task performance

Both bilingualism and attention contribute to the development of executive functioning (EF), with higher levels of both leading to better outcomes. The present study treats bilingualism and attention as continuous variables to investigate their impact on EF. Eighty-two 9-year-olds who were attending a French school in an anglophone community completed a flanker task. Children's progress in French represented their level of bilingualism, and attention was assessed through a standard standardized instrument. Degree of bilingualism and degree of attention were both positively related to performance, but exposure to a third language in the home did not further affect outcomes.

Executive Functions and Morphosyntax: Distinguishing DLD From ADHD in French-Speaking Children

Attention deficit hyperactivity disorder (ADHD) is commonly associated with deficits in executive functions executive functions (EF), but children with this disorder frequently demonstrate co-occurring morphosyntactic impairment when assessed using standardized tests. On the other hand, children with developmental language disorder (DLD), a population defined by impaired linguistic functioning, are often diagnosed with comorbid EF deficits. We investigated EF and morphosyntax in 60 French-speaking children aged six to 12: 20 with typical development (TD), 20 with ADHD, and 20 with DLD. To obtain an EF profile for the different cognitive groups, we used standardized tests to assess lower-order EF skills, (i) selective attention and (ii) short-term memory capacity, and higher-order EF skills, (i) working memory capacity and (ii) attention shifting. To test morphosyntax, we used (i) a standardized omnibus test that elicited a variety of complex structures and (ii) a more fine-grained probe test that assessed the production of third person object clitic pronouns, a clinical marker of DLD in French. Children with ADHD and DLD were associated with different EF and morphosyntactic profiles: children in the ADHD group demonstrated higher-order EF weakness and difficulty on the omnibus morphosyntax task, whereas children with DLD showed both lower- and higher-order limitations and struggled with both morphosyntax tasks. Our findings indicate that deficits in morphosyntax are not characteristic of ADHD but that the performance of children with ADHD can mimic morphosyntactic impairment when all-encompassing omnibus tests evaluating various and unpredictable structures are used. If morphosyntax is tested using reliable markers of atypical language development and external cognitive-load factors are optimally reduced, there are significant discrepancies in the observed ADHD-DLD outcomes. Clinical implications that include perspectives for the differential diagnosis of ADHD and DLD are discussed.

Task-induced pupil response and visual perception in adults

We assessed whether there are differences in pupil response that underlie the selection of local vs. global parts of a stimulus array in healthy adults. We designed a Navon Figures eyetracking paradigm (i.e. large figure composed of small figures), requiring an individual to vary only the information attended to within an image. We found that participants have a characteristic constriction of the pupil waveform during selection of local information relative to global information. Because stimuli and lighting conditions were identical across conditions, this indicates that pupil changes may serve in a visual filtering mechanism important for attentional selection. This work represents the first characterization of pupil response in the context of selective attention, suggesting that mechanisms underlying the earliest stages of visual processes could be relevant for perception and visual selection.

ENHANCING IMPLICIT LEARNING WITH POSTHYPNOTIC SUGGESTION: An ERP Study

Can posthypnotic suggestion (PHS) enhance cognitive abilities? The authors tested behaviorally and with event-related potentials (ERP) if sequential learning (SL), the ability to learn statistical regularities, can be enhanced with PHS. Thirty adults were assessed with the Stanford Hypnotic Susceptibility Scale (Form C) and an auditory SL task. Before this task, half the sample received a PHS to enhance SL, and the other half received the same suggestion under normal waking state. Response times and ERPs indicated a strong effect of PHS. Compared to the control group, PHS inverted, attenuated, or left unaffected the response time SL effect in low, medium, and high hypnotizability participants, respectively. These results suggest that PHS cannot be used to enhance SL.

Visual statistical learning is related to natural language ability in adults: An ERP study

Statistical learning (SL) is believed to enable language acquisition by allowing individuals to learn regularities within linguistic input. However, neural evidence supporting a direct relationship between SL and language ability is scarce. We investigated whether there are associations between event-related potential (ERP) correlates of SL and language abilities while controlling for the general level of selective attention. Seventeen adults completed tests of visual SL, receptive vocabulary, grammatical ability, and sentence completion. Response times and ERPs showed that SL is related to receptive vocabulary and grammatical ability. ERPs indicated that the relationship between SL and grammatical ability was independent of attention while the association between SL and receptive vocabulary depended on attention. The implications of these dissociative relationships in terms of underlying mechanisms of SL and language are discussed. These results further elucidate the cognitive nature of the links between SL mechanisms and language abilities.

Attention Functioning Among Adolescents With Multiple Learning, Attentional, Behavioral, and Emotional Difficulties

Attention-deficit/hyperactivity disorder (ADHD) is characterized by high levels of inattention, hyperactivity, and impulsivity; however, these symptoms can result from a variety of reasons. To obtain a comprehensive understanding of the various difficulties of individuals with ADHD, especially when co-occurrence difficulties are present, it is essential to combine neuropsychological and subjective assessment tools. In the present field study the authors investigated a group of adolescents with multiple deficits (MD) using neuropsychological and subjective measures. Teachers' ratings verified extremely high levels of symptoms of oppositional behavior, inattention, hyperactivity-impulsivity, social problems, and emotional problems in this group. As expected, MD group participants showed decreased abilities to maintain attention on task for a long period of time, focus attention and effectively inhibit adjacent distractors, and resist conflicting irrelevant information. Importantly, although significant differences in the attention measures were observed at the group level, not all MD participants displayed deviant performance. Thus, we conclude that the heterogeneous group of adolescents with MD comprises individuals with primary attention deficits as well as those with other nonattentional deficits that show equivalent behavioral symptoms. Using neuropsychological tools can be useful in differentiating between different core deficits and in guiding appropriate interventions.

ADHD symptomatology is best conceptualized as a spectrum: a dimensional versus unitary approach to diagnosis

The aim of this paper is to build a case for the utility of conceptualizing ADHD, not as a unitary disorder that contains several subtypes, but rather as a marker of impairment in attention and/or impulsivity that can be used to identify one of several disorders belonging to a spectrum. The literature will be reviewed to provide an overview of what is known about ADHD in terms of heterogeneity in symptomatology, neuropsychology, neurobiology, as well as comorbidity with other diseases and treatment options. The data from these areas of research will be critically analyzed to support the construct of a spectrum of disorders that can capture the great variability that exists between individuals with ADHD and can discriminate between separate disorders that manifest similar symptoms. The symptoms associated with ADHD can be viewed as dimensional markers that point to a spectrum of related disorders that have as part of their characteristics impairments of attention and impulsivity. The spectrum can accommodate symmetrically and asymmetrically comorbid psychiatric disorders associated with ADHD as well as the wide heterogeneity known to be a part of the ADHD disorder. Individuals presenting with impairments associated with ADHD should be treated as having a positive marker for a spectrum disorder that has as part of its characteristics impairments of attention and/or impulsivity. The identification of impairment in attention and/or impulsivity should be a starting point for further testing rather than being an endpoint of diagnosis that results in pharmacological treatment that may or may not be the optimal therapy. Rather than continuing to attribute a large amount of heterogeneity in symptom presentation as well as a high degree of symmetric and asymmetric comorbidity to a single disorder, clinical evaluation should turn to the diagnosis of the type of attentional deficit and/or impulsivity an individual has in order to colocate the individual's disorder on a spectrum that captures the heterogeneity in symptomatology, the symmetrical and asymmetrical comorbidity, as well as subthreshold presentation and other variants often worked into the disorder of ADHD. The spectrum model can accommodate not only the psychophysiological profiles of patients, but is also consistent with what is known about the functional heterogeneity of the prefrontal cortex as well as the construct that cognitive processes are supported by overlapping and collaborative networks.

Array Effects, Spatial Concepts, or Information Processing Speed

A reaction time/accuracy experiment investigated the development of visual memory for object shape and location in 6–7- and 8–9-year-old children and adults (N = 72) in three array types: (1) an empty screen, (2) a frame delineating a region, and (3) a grid with individually delineated places. A maximized learning design was used. Explicit array boundaries in the frame and in the grid facilitated place memory in both children and adults, while place memory in the empty screen was less correct, slower, and did not improve. Children’s visual memory was initially low, but learning during the task resulted in better object than place memory. Like the children at the end of the session, adults showed better object than place memory at the beginning of the task. They subsequently also improved their object memory, but doubled their place memory performance. Children with object-region binding showed better place memory and more systematic learning effects that were specific to arrays. However, neither array boundaries nor spatial binding concepts explained the absence of place learning in children. Instead, children tried to prevent proactive shape interference in the repeated memory sets at the cost of place learning, while adults did not.

The role of sustained attention and display medium in reading comprehension among adolescents with ADHD and without it

Difficulties in reading comprehension are common in children and adolescents with Attention Deficit/Hyperactivity Disorder (ADHD). The current study aimed at investigating the relation between sustained attention and reading comprehension among adolescents with and without ADHD. Another goal was to examine the impact of two manipulations of the text on the efficiency of reading comprehension: Spacing (standard- vs. double-spacing) and Type of presentation (computer screen vs. hard copy). Reading comprehension of two groups of adolescents (participants with ADHD and normal controls) was assessed and compared in four different conditions (standard printed, spaced printed, standard on computer screen, spaced on computer screen). In addition, participants completed a visual sustained attention task. Significant differences in reading comprehension and in sustained attention were obtained between the two groups. Also, a significant correlation was obtained between sustained attention and reading comprehension. Moreover, a significant interaction was revealed between presentation-type, spacing and level of sustained attention on reading comprehension. Implications for reading intervention and the importance of early assessment of attention functioning are discussed.

Which behavioral and personality characteristics are associated with difficulties in selective attention?

OBJECTIVE

The present study investigated the behavioral and personality profile associated with difficulties in selective attention.

METHOD

A group of participants with ADHD were assessed for ADHD behaviors. Adults with ADHD (n=22) and without ADHD (n=84) were tested on the conjunctive visual-search task for selective attention and behavioral measures, including ADHD behaviors, Big Five dimension of personality, obsessive compulsive disorder (OCD) symptoms, and sensation-seeking behavior.

RESULTS

Correlations and multiple regression analysis (group was dummy coded) showed that ADHD behaviors were not related to search performance. However, poorer search performance was related to greater neuroticism, agreeableness, introversion, lower sensation seeking, and, marginally, to OCD symptoms.

CONCLUSION

The study findings suggested that difficulties in selective attention are probably not associated with ADHD behaviors, but rather with personality traits characterized by preserving and avoiding high-stimulation behaviors.

How cognitive load affects duration judgments: A meta-analytic review

A meta-analysis of 117 experiments evaluated the effects of cognitive load on duration judgments. Cognitive load refers to information-processing (attentional or working-memory) demands. Six types of cognitive load were analyzed to resolve ongoing controversies and to test current duration judgment theories. Duration judgments depend on whether or not participants are informed in advance that they are needed: prospective paradigm (informed) versus retrospective paradigm (not informed). With higher cognitive load, the prospective duration judgment ratio (subjective duration to objective duration) decreases but the retrospective ratio increases. Thus, the duration judgment ratio differs depending on the paradigm and the specific type of cognitive load. As assessed by the coefficient of variation, relative variability of prospective, but not retrospective, judgments increases with cognitive load. The prospective findings support models emphasizing attentional resources, especially executive control. The retrospective findings support models emphasizing memory changes. Alternative theories do not fit with the meta-analytic findings and are rejected.

Stimulus effects on cancellation task performance in children with and without dyslexia

Both the sensitivity and administration time of a test are important in evaluating visuospatial attention in clinical settings, especially with respect to external validity. The purpose of the present study was to propose an adaptive model that provides a reference for test modification by manipulating target-to-distractor (T/D) ratios and the number of stimuli on the computerized cancellation test system. Tasks with different T/D ratios and numbers of stimuli were presented to two groups--children with and without dyslexia (n = 41 and 65, respectively)--to determine whether their visuospatial attention performance differed on different test forms. In general, there were significant differences between the two groups in hit rates, completion times, and performance quality (PQ) scores. The PQ score of visual attention was affected by the T/D ratios rather than by the number of stimuli. The findings suggested that the T/D ratio has a strong effect on PQ scores, and that it should be taken into consideration in test and task design.

Methylphenidate and nicotine focus responding to an informative discrete CS over successive sessions of appetitive conditioning

Methylphenidate (MP) and nicotine would be expected to improve associative learning, though previous evidence suggests that they should reduce the selectivity with which associations are formed. Here we tested their effects on learning the association between a conditioned stimulus (CS) and food (unconditioned stimulus, UCS) in male Wistar rats. The UCS was delivered immediately (0 s) following CS offset or after a 10 s trace. In addition to the measures of discrete CS conditioning, contextual and trace responding was measured in the inter-trial- and the inter-stimulus-interval, respectively. In all cases, conditioning was measured as nose poking for food. Both MP and nicotine improved the acquisition of discrete cue conditioning. Acquisition was accelerated (compared to saline) under 5 but not 1 mg/kg MP and 0.6, but not 0.4 mg/kg nicotine. In each case, this effect was observed in 0 s but not 10 s conditioned groups. For comparison, some earlier published data obtained following the same procedure with D-amphetamine were re-analysed in the same way. Amphetamine similarly improved conditioning in the 0 s group, in this case at 0.5, but not 1.5 mg/kg. Thus three different dopamine agonists increased the ability to focus responding to CS presentations over successive sessions of appetitive acquisition.

Neuropsychological Abilities of Preschool-Aged Children Who Display Hyperactivity and/or Oppositional-Defiant Behavior Problems

This study focused on gaining a better understanding of the neuropsychological abilities of preschool-aged children who show elevated levels of hyperactivity and oppositional-defiance. It examined the performance of children aged 48 to 67 months on tests of attention/executive function, language, memory, and sensorimotor abilities, as measured by the NEPSY and Conners' K-CPT. Two hundred thirty-seven children were divided into four subgroups based on mothers' report of behavior using rating scales and a diagnostic interview: hyperactive only (HYP), oppositional-defiant only (OD), hyperactive and oppositional-defiant (HYP/OD), and nonproblem. Children in the HYP/OD group scored significantly worse than nonproblem children on four of nine subtests on the NEPSY, including one test of executive function, one test of language comprehension, and both tests of short-term verbal memory. However, only the test of executive function (Statue) showed significant predictive power, and, while specificity of this subtest was good, sensitivity was poor. On the K-CPT, a continuous performance test, children in both the HYP and HYP/OD groups performed worse than children in the OD and nonproblem groups. When the NEPSY Statue subtest and the K-CPT were used together, overall predictive power was .74. Results suggest that neuropsychological deficits can be observed among preschool children with hyperactivity, particularly when comorbid oppositional-defiance is present; however, moderate predictive power suggests that these tests should be used in conjunction with other methods of assessment.

Methylphenidate can reduce selectivity in associative learning in an aversive trace conditioning task

There are good grounds to expect that methylphenidate (MP) should enhance cognitive function. However, experimental evidence on this point is scant. The present study therefore examined the effects of MP on learning the association between a conditioned stimulus (CS, in this case, noise) and an unconditioned stimulus (UCS, in this case, footshock) in an aversive variant of a trace conditioning procedure. Learning was measured off-the-baseline as conditioned suppression of drinking (both latencies to drink, expressed as suppression ratios, and the amount drunk, expressed as the number of licks, in the presence of the CS). In addition to the measures of discrete cue conditioning, MP effects on contextual conditioning were measured as suppression to apparatus cues and an experimental background stimulus. MP was administered at 1 or 5 mg/kg prior to conditioning sessions. As attention deficit hyperactivity disorder (ADHD) has been characterized as involving a ;wide attentional window' (e.g. Shalev and Tsal, 2003), it was predicted that MP, as the treatment of choice for ADHD, should increase selectivity (narrowing the attentional window). This outcome would show as reduced levels of conditioning (compared to control rats) to less informative trace and contextual cues present during conditioning. Contrary to prediction, both 1 and 5 mg/kg MP increased learning about all the available stimuli, including the less informative trace CS and the background stimulus. These findings are consistent with reduced rather than increased selectivity in learning (because of increased rather than decreased conditioning to weak cues) under MP.

Effect of action video games on the spatial distribution of visuospatial attention

The authors investigated the effect of action gaming on the spatial distribution of attention. The authors used the flanker compatibility effect to separately assess center and peripheral attentional resources in gamers versus nongamers. Gamers exhibited an enhancement in attentional resources compared with nongamers, not only in the periphery but also in central vision. The authors then used a target localization task to unambiguously establish that gaming enhances the spatial distribution of visual attention over a wide field of view. Gamers were more accurate than nongamers at all eccentricities tested, and the advantage held even when a concurrent center task was added, ruling out a trade-off between central and peripheral attention. By establishing the causal role of gaming through training studies, the authors demonstrate that action gaming enhances visuospatial attention throughout the visual field.

Selective visual attention ensures constancy of sensory representations: Testing the influence of perceptual load and spatial competition

We report findings from several variants of a psychophysical experiment using an acceleration detection task in which we tested predictions derived from recent neurophysiological data obtained from monkey area MT. The task was designed as a Posner paradigm and required subjects to detect the speed-up of a moving bar, cued with 75% validity. Displays varied according to number of simultaneously presented objects, spatial distance, and difficulty of the task. All data obtained under different levels of competition with multiple objects were compared to a corresponding condition, in which only a single moving bar was presented in the absence of any interfering distracter object. For attended objects, subjects did not show any difference in their ability to detect accelerations, regardless of the strength of inter-object competition or spatial distance. This finding was consistent in all of the experiments, and was even obtained when the acceleration was made hardly detectable. In contrast, increasing competitive interactions either by enhancing number of objects or spatial proximity resulted in strong reduction of performance for non-attended objects. The findings support current noise reduction models and suggest that attention adjusts neuronal processing to ensure a constant sensory representation of the attended object as if this object was the only one in the scene.

The diversity of attention deficits in ADHD: the prevalence of four cognitive factors in ADHD versus controls

The performance of participants with attention-deficit/hyperactivity disorder (ADHD) relative to control participants was measured on four tasks uniquely assessing the functions of selective attention, executive attention, sustained attention, and orienting of attention. The results showed that deficits in sustained attention were the most pronounced, characterizing most participants with ADHD and deficits in each of the other three functions characterized more than half of these participants. Different participants with ADHD revealed different clusters of attentional deficits. These results call for a revision of leading theories of ADHD that identify the core of the pathology as a sole deficit in executive functions.