Learning,Attention, Writing,and Processing Speed in Typical Children and Children with ADHD,Autism, Anxiety,Depression, and Oppositional-Defiant Disorder

Learning, attention, graphomotor, and processing speed scores were analyzed in 149 typical control children and 886 clinical children with normal intelligence. Nonsignificant differences were found between control children and children with anxiety, depression, and oppositional-defiant disorder. Control children performed better than children with ADHD and autism in all areas. Children with ADHD and autism did not differ, except that children with ADHD had greater learning problems. Attention, graphomotor, and speed weaknesses were likely to coexist, the majority of children with autism and ADHD had weaknesses in all three areas, and these scores contributed significantly to the prediction of academic achievement.     

An investigation into the relationship among ADHD symptomatology, creativity, and neuropsychological functioning in children.

This paper examined the relationship between creativity and ADHD symptomatology. First, the presence of ADHD symptomatology within a creative sample was explored. Secondly, the relationship between cognitive functioning and ADHD symptomatology was examined by comparing four groups, aged 10-12 years: 1) 29 ADHD children without creativity, 2) 12 creative children with ADHD symptomatology, 3) 18 creative children without ADHD symptomatology, and 4) 30 controls. Creativity, intelligence, processing speed, reaction time, working memory, and inhibitory control were measured. Results showed that 40% of the creative children displayed clinically elevated levels of ADHD symptomatology, but none met full criteria for ADHD. With regard to cognitive functioning, both ADHD and creative children with ADHD symptoms had deficits in naming speed, processing speed, and reaction time. For all other cognitive measures the creative group with ADHD symptoms outperformed the ADHD group. These findings have implications for the development and management of creative children.     

Evaluating the endophenotype model of ADHD neuropsychological deficit: results for parents and siblings of children with ADHD combined and inattentive subtypes

Neurogenetic models predict neuropsychological weaknesses in the relatives of children with attention-deficit/ hyperactivity disorder (ADHD). The authors examined executive and regulatory measures in 386 relatives (307 parents, 79 siblings) of children with ADHD combined type, ADHD inattentive type, and controls. Predicted deficits were seen on trailmaking (relatives of ADHD combined type only), stop-signal reaction times (relatives of girls only), and response variability (mothers only) but not on naming or output speed. Effects generally held, even with relatives' ADHD status controlled. A neuropsychologically impaired subgroup of children with ADHD had relatives with clear neuropsychological weaknesses. The authors conclude that a neurogenetic model of ADHD etiology is supportable only for a subset of executive functions and that neuropsychological heterogeneity warrants more examination in ADHD.     

Reduced graphomotor procedural learning in children and adolescents with ADHD

Purpose: The present study sought to determine if children and adolescents with ADHD demonstrate reduced procedural learning of a graphomotor program. Method: Thirty-two children and adolescents between age 9 and 15 with (n = 16) and without ADHD (n = 16) participated in the study. Each group of participants practiced a novel grapheme on a digitizing tablet 30 times. Participants with ADHD were off stimulant medication or were medication naïve. Results: Control participants demonstrated significant improvement in graphomotor fluency from the beginning to the end of practice, T = 2, z = −2.534, p = .009, whereas participants with ADHD did not, T = 4, z = −1.810, p = .074. Conclusions: Consistent with findings in adults with ADHD, results indicate that graphomotor procedural learning in children and adolescents with ADHD is attenuated. Findings have implications for future research that may inform remediation of handwriting difficulties, academic accommodations, and using digitizing technology for neuropsychological assessment.     

Smaller splenium in children with nonverbal learning disability compared to controls,high-functioning autism and ADHD

The current study investigated morphological differences in the corpus callosum in children ages 8 to 18 years old with nonverbal learning disability (NLD; n = 19), high-functioning autism (HFA; n = 23), predominantly inattentive ADHD (ADHD:PI; n = 23), and combined type ADHD (ADHD:C; n = 25), as well as those demonstrating typical development (n = 57). Midsagittal area of the corpus callosum and five midsagittal anterior-to-posterior corpus callosum segments were examined using magnetic resonance imaging. Controlling for midsagittal brain area and age, no group differences were found for total corpus callosum area. This finding indicates that higher functioning children on the autistic spectrum do not have smaller corpus callosi as has been found in previous research with heterogeneous samples. Following segmentation of the corpus callosum, the NLD group was observed to have significantly smaller splenia compared to all other groups. Smaller splenia in the NLD group was associated with lower WASI PIQ scores but not WASI VIQ scores. Children with HFA were observed to have larger midbody areas than children with NLD and neurotypically developing children. Children with HFA and NLD demonstrated behavioral symptoms of inattention and hyperactivity similar to the ADHD groups indicating that corpus callosum differences seen in the NLD and HFA groups are not related to these behaviors.     

Use of Gilliam Asperger's disorder scale in differentiating high and low functioning autism and ADHD

Little is known about the validity of Gilliam Asperger's Disorder Scale (GADS), although it is widely used. This study of 199 children with high functioning autism or Asperger's disorder, 195 with low functioning autism, and 83 with attention deficit hyperactivity disorder (ADHD) showed high classification accuracy (autism vs. ADHD) for clinicians' GADS Quotients (92%), and somewhat lower accuracy (77%) for parents' Quotients. Both children with high and low functioning autism had clinicians' Quotients (M=99 and 101, respectively) similar to the Asperger's Disorder mean of 100 for the GADS normative sample. Children with high functioning autism scored significantly higher on the cognitive patterns subscale than children with low functioning autism, and the latter had higher scores on the remaining subscales: social interaction, restricted patterns of behavior, and pragmatic skills. Using the clinicians' Quotient and Cognitive Patterns score, 70% of children were correctly identified as having high or low functioning autism or ADHD.     

An Investigation into the Relationship Among ADHD Symptomatology,Creativity, and Neuropsychological Functioning in Children

This paper examined the relationship between creativity and ADHD symptomatology. First, the presence of ADHD symptomatology within a creative sample was explored. Secondly, the relationship between cognitive functioning and ADHD symptomatology was examined by comparing four groups, aged 10–12 years: 1) 29 ADHD children without creativity, 2) 12 creative children with ADHD symptomatology, 3) 18 creative children without ADHD symptomatology, and 4) 30 controls. Creativity, intelligence, processing speed, reaction time, working memory, and inhibitory control were measured. Results showed that 40% of the creative children displayed clinically elevated levels of ADHD symptomatology, but none met full criteria for ADHD. With regard to cognitive functioning, both ADHD and creative children with ADHD symptoms had deficits in naming speed, processing speed, and reaction time. For all other cognitive measures the creative group with ADHD symptoms outperformed the ADHD group. These findings have implications for the development and management of creative children.     

WISC-III Cognitive Profiles in Children with ADHD: Specific Cognitive Impairments and Diagnostic Utility

This study aimed to investigate the presence of specific cognitive impairments and the diagnostic utility of the WISC-III in children with ADHD. Ninety-eight children with ADHD and 81 children without ADHD matched by age and gender (control group), between the ages of 6 and 12?years, participated in the study. Children with ADHD revealed the most pronounced deficits in the subtests tapping working memory and processing speed. Freedom from Distractibility was the cognitive profile most impaired and that showed the highest diagnostic accuracy to discriminate children with ADHD. The optimal cutoff scores of the most common WISC-III cognitive profiles revealed greater diagnostic accuracy than the traditional approach of full or partial profiles. Taken together, these results suggested that in the context of a comprehensive psychological assessment, the WISC may provide knowledge about the specific cognitive strengths and weaknesses that characterize this disorder and may be useful in the decision-making process relative to ADHD diagnosis.     

Perceptuomotor functioning in preschool children with symptoms of attention deficit hyperactivity disorder

Given limited research on perceptual-motor functioning of preschool children with symptoms of ADHD, the purpose of this study was to compare the fine motor, gross motor, visuomotor, and oral-motor functioning of 49 4- to 6-yr.-old children with symptoms of Attention Deficit Hyperactivity Disorder and 48 typically developing children. Analysis showed scores of the ADHD group were significantly lower than those of the control group on all perceptuomotor measures. In addition, scores on all measures yielded significant correlations with scores on the Hyperactive-Inattentive scale of the Preschool Behavior Questionnaire. Regression analyses indicated that the scores of gross motor and visuomotor functioning were significant predictors of group classification (with and without ADHD). These findings extend the well documented findings of perceptuomotor deficits among school-age children with ADHD into the preschool period and emphasize the importance of early assessment and treatment of these deficits in young children with symptoms of ADHD.     

WISC-IV and WISC-III profiles in children with ADHD

Wechsler Intelligence Scale for Children, 3rd and 4th editions (WISC-III n = 586 and WISC-IV n = 118), profiles were compared for children with ADHD and normal intelligence. Mean Verbal Comprehension Index (VCI) and Perceptual Organization/Perceptual Reasoning Index (POI/PRI) scores were significantly higher than Freedom From Distractibility/Working Memory Index (FDI/WMI) and Processing Speed Index (PSI), and Symbol Search was higher than Coding. FDI/WMI and PSI scores were similar on both tests, but VCI and POI/PRI were higher on the WISC-IV than on the WISC-III. Therefore, index discrepancies were greater for the WISC-IV, suggesting that the WISC-IV might be better than the WISC-III in delineating the strengths and weaknesses of children with ADHD. All children in the WISC-IV sample scored lowest on WMI or PSI, whereas only 88% of the WISC-III children scored lowest on FDI or PSI. Thus, the WISC-IV may be more helpful in diagnosing ADHD than the WISC-III.     

Variability of kinematic graphomotor fluency in adults with ADHD

Although graphomotor differences and variability of performance have been observed in children with attention deficit hyperactivity disorder (ADHD), no study has investigated whether this variability manifests in the kinematic graphomotor domain in adults with ADHD. Fourteen ADHD and 20 control participants wrote a novel grapheme and common word on a digitizing tablet 30 times each, with ADHD participants counterbalanced on and off stimulant medication. Variability of graphomotor fluency was significantly greater in ADHD versus control participants only in the novel writing task, both on, F(1, 31) = 5.988, p = .020, and off stimulant medication, F(1, 32) = 8.789, p = .006. Results suggest that motor control differences in ADHD are not limited to childhood and extend into adulthood. Given sufficient additional research, variability of kinematic graphomotor fluency may increase the sensitivity/specificity of differential diagnoses and/or represent a biomarker for ADHD.     

Cross-Sectional Age Analysis of Sleep Problems in 2 to 17 Year Olds with ADHD Combined,ADHD Inattentive,or Autism

Sleep problems are common in autism and ADHD. No study has compared sleep problems by age in 2 to 17 year olds with autism versus ADHD-Combined versus ADHD-Inattentive type. Mothers rated 1415 youth with autism and 1041 with ADHD on 10 Pediatric Behavior Scale sleep items. Nighttime sleep problems were most severe in autism, followed by ADHD-Combined, and then ADHD-Inattentive. Difficulty falling asleep, restless during sleep, and waking during the night were the most common problems. Adolescents slept more at night than other age groups, and youth who slept more at night were sleepier during the day. Sleep problems declined with age, but correlations were small. In adolescence, 63% with autism, 53% with ADHD-Combined, and 57% with ADHD-Inattentive had difficulty falling asleep. Given that the majority of children in all age groups had one or more sleep problem, developmentally appropriate interventions are needed to address sleep difficulties and limit their adverse effects.

     

Heterogeneity in ADHD: Neurocognitive predictors of peer,family, and academic functioning

Childhood attention-deficit/hyperactivity disorder (ADHD) is associated with impairments in peer, family, and academic functioning. Although impairment is required for diagnosis, children with ADHD vary significantly in the areas in which they demonstrate clinically significant impairment. However, relatively little is known about the mechanisms and processes underlying these individual differences. The current study examined neurocognitive predictors of heterogeneity in peer, family, and academic functioning in a well-defined sample of 44 children with ADHD aged 8–13 years (M = 10.31, SD = 1.42; 31 boys, 13 girls; 81% Caucasian). Reliable change analysis indicated that 98% of the sample demonstrated objectively-defined impairment on at least one assessed outcome measure; 65% were impaired in two or all three areas of functioning. ADHD children with quantifiable deficits in academic success and family functioning performed worse on tests of working memory (d = 0.68 to 1.09), whereas children with impaired parent-reported social functioning demonstrated slower processing speed (d = 0.53). Dimensional analyses identified additional predictors of peer, family, and academic functioning. Working memory abilities were associated with individual differences in all three functional domains, processing speed predicted social functioning, and inhibitory control predicted family functioning. These results add to a growing literature implicating neurocognitive abilities not only in explaining behavioral differences between ADHD and non-ADHD groups, but also in the substantial heterogeneity in ecologically-valid functional outcomes associated with the disorder.     

Writing abilities and the role of working memory in children with symptoms of attention deficit and hyperactivity disorder

The writing abilities of children with ADHD symptoms were examined in a simple dictation task, and then in two conditions with concurrent verbal or visuospatial working memory (WM) loads. The children with ADHD symptoms generally made more spelling mistakes than controls, and the concurrent loads impaired their performance, but with partly different effects. The concurrent verbal WM task prompted an increase in the phonological errors, while the concurrent visuospatial WM task prompted more non-phonological errors, matching the Italian phonology, but not the Italian orthography. In the ADHD group, the children proving better able to cope with a concurrent verbal WM load had a better spelling performance too. The ADHD and control groups had a similar handwriting speed, but the former group’s writing quality was poorer. Our results suggest that WM supports writing skills, and that children with ADHD symptoms have general writing difficulties, but strength in coping with concurrent verbal information may support their spelling performance.     

Naming Speed Performance and Stimulant Effects Indicate Effortful, Semantic Processing Deficits in Attention-Deficit/Hyperactivity Disorder

This study investigated rapid automatized naming and effects of stimulant medication in school-age children with attention-deficit/hyperactivity disorder (ADHD) with and without concurrent reading disorder (RD). Two ADHD groups (67 ADHD only; 21 ADHD + RD) and a control group of 27 healthy age-matched peers were compared on four variables: color naming speed, letter naming speed, phonologic decoding, and arithmetic computation. Discriminant function analysis (DFA) was conducted to predict group membership. The four variables loaded onto two discriminant functions with good specificity: phonologic decoding, letter naming speed, and arithmetic defined the first function; color naming speed defined the second function. Both ADHD groups were significantly slower in color naming than controls, but did not differ from one another. DFA correctly classified 96% of the control group, 91% of ADHD + RD, and 82% of ADHD only. A subset of children in the ADHD groups participated subsequently in an acute, randomized, placebo-controlled, crossover trial with three single doses (10, 25, 20 mg) of methylphenidate. Methylphenidate selectively improved color-naming speed but had no effect on the speed of naming letters or digits. These findings challenge the tenet that naming speed deficits are specific to RD and implicate naming speed deficits associated with effortful semantic processing in ADHD, which are improved but not normalized by stimulant medication.     

A comparison of working memory profiles in children with ADHD and DCD

The main objective of present study was to investigate whether the patterns of working memory performance differ as a function of attention and motor difficulties, and whether children with ADHD and DCD could be reliably discriminated on the basis of their memory deficits. A related aim was to investigate the link between their working memory profiles and academic attainment. Fifty children with ADHD-Combined, 55 children with DCD, and an age-matched group of 50 typically developing children with average working memory were assessed on standardized measures of working memory, IQ, and academic attainment (reading, spelling, comprehension, and math). The normal controls performed significantly better than both clinical groups on all working memory tests. Specific patterns emerged in the memory profile of the clinical groups: The children with DCD had a depressed performance in all working memory tests, with particularly low scores in visuospatial memory tasks; children with ADHD performed within age-expected levels in short-term memory but had a pervasive working memory deficit that impacted both verbal and visuospatial domains. The clinical groups could reliably be discriminated on the basis of their short-term memory scores. Their learning profiles were similar. It is possible that the working memory profiles of the children with ADHD and DCD are influenced by distinct underlying cognitive mechanisms, rather than a general neurodevelopmental delay. Despite these distinctive patterns of memory performance, both clinical groups performed similarly on academic attainments, suggesting that memory may underlie learning difficulties, independent of related clinical disorders.     

Sleep disturbance and neuropsychological function in young children with ADHD

Sleep disturbance, common among children with ADHD, can contribute to cognitive and behavioral dysfunction. It is therefore challenging to determine whether neurobehavioral dysfunction should be attributed to ADHD symptoms, sleep disturbance, or both. The present study examined parent-reported sleep problems (Children’s Sleep Habits Questionnaire) and their relationship to neuropsychological function in 64 children, aged 4–7 years, with and without ADHD. Compared to typically developing controls, children with ADHD were reported by parents to have significantly greater sleep disturbance—including sleep onset delay, sleep anxiety, night awakenings, and daytime sleepiness—(all p ≤ .01), and significantly poorer performance on tasks of attention, executive control, processing speed, and working memory (all p < .01). Within the ADHD group, total parent-reported sleep disturbance was significantly associated with deficits in attention and executive control skills (all p ≤ .01); however, significant group differences (relative to controls) on these measures remained (p < .01) even after controlling for total sleep disturbance. While sleep problems are common among young children with ADHD, these findings suggest that inattention and executive dysfunction appear to be attributable to symptoms of ADHD rather than to sleep disturbance. The relationships among sleep, ADHD symptoms, and neurobehavioral function in older children may show different patterns as a function of the chronicity of disordered sleep.     

Stimulus-response incompatibility effects on event-related potentials in children with attention-deficit hyperactivity disorder

In order to test the hypothesis of a response choice deficit in attention-deficit hyperactivity disorder (ADHD) children, event-related potentials (ERPs) were recorded from 30 scalp electrodes in 21 ADHD and 21 normal boys during a spatial stimulus-response compatibility (SRC) task. ADHD children made fewer correct responses than control children, but did not show a larger incompatibility effect on response speed and accuracy. In ERPs, ADHD children had longer N1 latency and larger condition effect on the frontal N2, which would reflect a greater frontal involvement for the correct responses. The ADHD group who performed the SRC task first showed a larger condition effect on an early occipital P3 only, while the ADHD group who performed the SRC task second showed a larger condition effect on a later central P650 component and on a late parietal NSW, as compared with normal controls. These results suggest strategic differences in information processing in ADHD children, rather than a specific deficit.     

Sustained attention and visual processing speed in children and adolescents with bipolar disorder and other psychiatric disorders

To investigate the cognitive functioning of children and adolescents with bipolar illness, 112 child and adolescent psychiatric inpatients and day-hospital patients at a state psychiatric hospital were administered the Wechsler Intelligence Scale for Children-III (WISC-III) as part of an admission psychological assessment. There were 22 patients with Bipolar Disorder and 90 with other psychiatric disorders; all were between 8 and 17 years of age. The patients with Bipolar Disorder had a mean age of 14 yr., a mean Verbal IQ of 78, a mean Performance IQ of 76, and a mean Full Scale IQ of 75. When their WISC-III scores were compared with those who had Schizophrenia Spectrum disorders (Schizophrenia and Schizoaffective Disorder), Psychosis Not Otherwise Specified, Attention Deficit Hyperactivity Disorder, and Conduct Disorder and Oppositional Defiant Disorder, there were no significant between-group mean differences for Verbal IQ, but patients with Bipolar Disorder had a significantly lower mean Performance IQ than those with ADHD and those with Conduct Disorder and Oppositional Defiant Disorder. Contrary to the expectation that the patients with Bipolar Disorder might have better sustained attention (higher Digit Span scores) than those with Schizophrenia Spectrum disorders and worse visual processing speed (lower Coding scores) than the other diagnostic groups, the bipolar patients' Digit Span and Coding scores did not differ significantly from those of the other groups. The patients with Psychosis, Not Otherwise Specified had significantly lower mean Performance IQ, Full Scale IQ, and Coding than the ADHD and the Conduct Disorder and Oppositional Disorder groups.     

Executive functions and ADHD in adults: evidence for selective effects on ADHD symptom domains

Dual-process models of attention-deficit/hyperactivity disorder (ADHD) suggest that both executive functioning and regulatory functions (e.g., processing speed) are involved and that executive function weaknesses may be associated specifically with symptoms of inattention-disorganization but not hyperactivity-impulsivity. Adults aged 18-37 (105 with ADHD, 90 controls) completed a neuropsychological battery. The ADHD group had weaker performance than did the control group (p<.01) on both executive and speed measures. Symptoms of inattention-disorganization were uniquely related to executive functioning with hyperactivity-impulsivity controlled. Inattention was associated with slower response speed, and hyperactivity-impulsivity with faster output speed. Results were not accounted for by IQ, age, gender, education level, or comorbid disorders. Findings are discussed in terms of developmental and dual-process models of ADHD leading into adulthood.