"We found children with ADHD-PI and ADHD-C had slower perceptual and psychomotor/incidental learning speed than controls and that ADHD-PI had slower decision speed than controls."
"This study provides foundational data to identify herbs that are potentially effective in treating ADHD by text mining of Donguibogam, which is a comprehensive summation of the important traditional principles and practices of Korean medicine."
"Effects of taijiquan and qigong practice (bewegende-meditatie) over behavioural disorders in school-age children: Results showed very interesting improvements in symptoms of CD, ODD and ADHD-HI (hyperactive-impulsive), while ADHD-PI (predominantly inattentive) showed only minor improvements."
"As ADHD-I is the most common form of ADHD presented by children in community settings, it is important to consider how treatment interventions for children with ADHD-I may be affected by deficits in processing speed and working memory."
"Our results suggest that the clinical distinction between the Inattentive and Combined subtypes of ADHD may also be reflected in distinct aberrations in underlying brain organization."
Receipt of pharmacotherapy could decrease risk of substance use in adolescents with ADHD-H and ADHD-C, but it may not affect risk of substance use among individuals with ADHD-I.
"Differences in WM microstructure in ADHD presentations strengthen the theory that ADHD-PI and ADHD-C are two distinct disorders. This study aimed to provide novel insights into the white matter (WM) microstructural properties of ADHD subtypes. With the ADHD predominantly inattentive group (ADHD-I) we detected increased RD in several bilateral brain area and increased AD mostly in left side of the brain."
"14% of children with ADHD-I obtain less sleep than recommended and 31% have a sleep onset latency of greater than 20 minutes. 27% of parents indicated that it is "difficult" to get their child out of bed on school days. 41% of parents indicated that their child needs to catch-up on sleep on the weekend "at least a little".
"The fMRI data suggested that more attention-related posterior brain regions (especially temporo-occipital areas) are activated in ADHD-RI during both Go and No-Go cues compared to TD controls and ADHD predominantly inattentive type. ADHD-RI may represent a different phenotype than other types of ADHD."
"The ADHD-I children differed significantly from the typically developing children with respect to attentional measures, such as the ability to maintain response-time consistency throughout the task, vigilance, processing speed, selective attention, sustained attention, error profile (Response Style), and inhibitory control (Perseverations)."
"Our results showed that only 5 % of both the control group and the group with solely mathematical difficulties fulfilled the criteria of an ADHD subtype according to the DSM-IV based on parents’ ratings. The relationship between learning difficulties and ADHD symptoms can be found predominantly in the inattentive type. Possible reasons for the results are discussed."
"Findings suggest that mothers of children with ADHD-HI/C reported significantly greater parenting stress and engaged in more negative parenting behaviors than mothers of children with ADHD-I."
"ADHD boys had a poorer static postural control ability and impaired function of processing visual and vestibular information compared with the normal control. Boys with ADHD-I showed particularly severe defect of static postural control and vestibular function integrating conflict information than normal boys. "
"Specifically, higher severity of inattention was associated with higher rates of homework, social, and home impairment. Negative parenting contributed to homework and home impairment, and positive and negative parenting contributed to social impairment, incrementally above and beyond the impact of inattention symptom severity alone. "
"Compared the neuropsychological characteristics and MPH treatment responses of patients with the R subtype-which has been suggested for inclusion among the ADHD subtypes in the DSM Fourth Edition-with those of patients with the PI and CB subtypes. They did not differ from the control subjects in the complex attention domain, which includes Continuous Performance Test, Stroop test, and Shifting Attention Test, which suggests that the R subtype displayed a lower level of deterioration in these domains compared with the PI and CB subtypes."
"The children and adolescents with ADHD-PI showed a significant right-ear advantage also during the FL condition, while the children and adolescents in the ADHD-C group showed a no-ear advantage and the HC showed a significant left-ear advantage in the FL condition. This suggests that the ADHD subtypes differ in degree of cognitive control impairment. "
"Much evidence of hemisphere asymmetry has been found for ADHD probands from behavioral level, electrophysiological level and brain morphology. One previous research has reported possible association between BAIAP2, which is asymmetrically expressed in the two cerebral hemispheres, with ADHD in European population. Results indicated the possible involvement of BAIAP2 in the etiology of ADHD, especially ADHD-I."
"As hypothesized, however, the relation between negative social preference and internalizing symptoms was moderated by sex such that negative social preference was consistently and more strongly associated with internalizing symptoms among girls than in boys. In terms of externalizing problems, negative social preference was associated with teacher (but not parent) ratings, yet no moderation by child sex was found."
"This article presents a model suggesting that over time, ADHD (predominantly inattentive type) develops into a syndrome of chronic fatigue and pain. These cases indicate that fatigue may be an important presenting symptom of adult ADHD."
"The spontaneously hypertensive and Wistar Kyoto rat models of ADHD exhibit sub-regional differences in dopamine release and uptake in the striatum and nucleus accumbens: the WKY/NCrl model of ADHD-PI exhibited faster DA uptake in the NAc versus the SD control. These results suggest that increased surface expression of DA transporters may explain the more rapid uptake of DA in the Str and NAc of these rodent models of ADHD."
"Analyses of diagnostic subtypes indicated that the predominantly inattentive type is the most common subtype in the population, but individuals with the combined type are more likely to be referred for clinical services. Additional research is needed to determine the etiology of the higher prevalence of ADHD in males than females and to clarify whether the prevalence of ADHD varies as a function of socioeconomic status or ethnicity."
"Time course of the development of depressive mood and oppositional defiant behavior among boys with attention deficit hyperactivity disorder: differences between subtypes: The DSRS score was significantly higher in the DD group compared to the ADHD-I and ADHD-C groups."
"This study's results indicate that ADHD symptoms are under-reported for both inattentive and hyperactive-impulsive clusters, indicating that adults with ADHD tend to under-estimate their own ADHD-related impairments. "
"Distinguishing Sluggish Cognitive Tempo From Attention-Deficit/Hyperactivity Disorder in Adults.
Russell A. Barkley, Ph.D.
Medical University of South Carolina"
"Nigeria: The prevalence of ADHD was 7.6%. The prevalence was higher in boys (9.4%) when compared to girls (5.5%) (P = 0.003). Of the three different subtypes of ADHD, the predominantly inattentive subtype (ADHD-I) was the most prevalent (47.3% of the ADHD population) followed by the combined type (ADHD-C; 31.3%), while the least prevalent was the hyperactive/impulsive subtype (ADHD-HI; 21.4%). There was no statistically significant difference in the prevalence of ADHD amongst the different age cohorts. The prevalence of ADHD was relatively high when compared to the figures available for other countries."
"Slower cognitive interference speed was found in the ADD vs. ADHD-C and controls comparisons, but not the ADHD-PI versus ADHD-C and controls comparisons. On output speed measures, ADD exhibited the slowest performance, significantly different from controls and the effect size for the set-shifting speed contrast (Trailmaking B) was double that of the ADHD-PI vs. control comparison. ADHD-Inattentive type as defined by the DSM-IV-TR is a heterogeneous condition with a meaningful proportion of those affected exhibiting virtually no hyperactive/impulsive symptoms. This subgroup may represent a distinct inattentive condition characterized by poor cognitive interference control and slow processing or output speed."
"The ADHD-C and ADHD-I groups had more daytime inadvertent napping. In general, the three subtypes were associated with increased rates of sleep problems/disorders. Specifically, ADHD-C rather than ADHD-I was associated with circadian rhythm problems, sleep-talking, nightmares (also ADHD-HI), and ADHD-I was associated with hypersomnia. The most-related sleep schedules and problems for inattention and hyperactivity-impulsivity were earlier bedtime, later rise time, longer nocturnal sleep, more frequent daytime napping, insomnia, sleep terrors, sleep-talking, snoring, and bruxism across informants. "
"Methylphenidate normalizes elevated dopamine transporter densities in an animal model of the attention-deficit/hyperactivity disorder combined type, but not to the same extent in one of the attention-deficit/hyperactivity disorder inattentive type. These results suggest differences in the pathophysiology of the combined versus the predominantly inattentive animal model of ADHD."
"Most (98%) teachers recognized the presence of a problem but mainly conceptualized the girl's behaviour as reflecting attentional (89%) or emotional (62%) difficulties. Teachers were less likely to correctly identify a girl with inattentive than combined subtype ADHD (14% vs. 43%) or recommend clinical referral (50% vs. 59%) for her. Few (15%) teachers thought that medication might be helpful for a girl meeting diagnostic criteria for ADHD."
"These data provide solid behavioral and genetic evidence that the WKY/NCrl and WKY/NHsd rats should be considered as separate substrains. Moreover, the behavioral features of the WKY/NCrl rat indicate that it should be a useful model for ADHD-PI, the primarily inattentive subtype of ADHD. The present results support the conclusion that SHR/NCrl is the best validated animal model of ADHD-C. The overactivity, impulsiveness and deficient sustained attention of the SHR/NCrl strain are independent behaviors. Thus, overactivity does not account for this strain's impulsiveness and deficient sustained attention."
"Univariate tests showed that the ADHD group performed worse than NCs on all of the dependent variables. Exploratory univariate analyses showed that oppositional defiant disorder comorbidity and ADHD type did not influence results except for the ICV, the effect for this variable (more variability in the ADHD group) being less pronounced for the Predominantly Inattentive type than for the Hyperactive-Impulsive and Combined types. "
"Blood lead levels were statistically significantly higher in ADHD-combined type than in non-ADHD control children. Blood lead was associated with symptoms of hyperactivity-impulsivity but not inattention-disorganization, after control of covariates. Blood lead levels were linked with a lower IQ, but IQ did not account for effects on hyperactivity. Instead, hyperactivity mediated effects of lead on IQ. Low-level lead exposure might be an important contributor to ADHD."
"Differences between the subtypes of Attention Deficit Hyperactivity Disorder (ADHD) continue to have a place in the clinical and research literature. The purpose of this study was to examine differences specific to academic and executive function deficits in a sample of 40 children, aged 9-15 years. Although there was a tendency for the Predominantly Inattentive (PI) group to evidence lower performance on calculation and written expression tasks, these differences dissipated when IQ was included as a covariate"
"Contrary to other studies there were no significant differences either between both ADHS types or relative to the control group with regard to the CPT omission errors and the reaction time. There were differences in the reaction variability both between the ADHD subtypes and relative to the control group. Only the "combined subtype", not the "pre-dominantly inattentive type" differed from the control group as to the CPT commission errors. Regarding the DAT, there were significant differences between all three groups regarding both the solution quality and the response delay."
"ADD (ADHD without hyperactivity), a Neurobiologically and Behaviorally Distinct Disorder from ADHD (with hyperactivity)
Adele Diamond (2005)
Development and Psychopathology, 17, pages 807-825
Most studies of ADHD have focused on the combined type and emphasized a core problem in response inhibition. We’ve proposed that ADHD of the truly inattentive type is a fundamentally different disorder from the other types of ADHD, with different brain systems affected, different genes implicated, different behavioral profiles, different underlying cognitive deficits, different patterns of co-morbidities, and different responses to medication."
"Chronic snoring may be a correlated feature in only a subgroup of the ADHD population, possibly those more likely to be diagnosed with ADHD-HI. Although children with ADHD have poorer sleep quality and greater daytime sleepiness, these 2 features of ADHD are not closely related."
"Thus, although ADHD is associated with the familial trans-mission of comorbid disorders, the pattern of transmission is not influenced by the proband's gender. These similar patterns provide further evidence for the idea that, when ADHD is diagnosed in girls it corresponds to the same disorder diagnosed in boys."
"Thus, SCT identifies a more homogeneous subgroup of ADHD/IA children who are, relative to the entire Diagnostic and Statistical Manual of Mental Disorders (4th ed. [DSM-IV]; American Psychiatric Association [APA], 1994) diagnosed ADHD/IA group, more similar to those classified in previous research as "attention deficit disorder without hyperactivity." These results support a reconsideration of SCT symptoms as a component of diagnostic criteria for a category of nonhyperactive attention deficit disorder."
"This study investigated age-related changes and sex differences in the EEGs of two groups of children with attention-deficit/hyperactivity disorder (ADHD) combined type and ADHD predominantly inattentive type, in comparison with a control group of normal children."
"Results partially confirmed our hypotheses. Subtyping ADHD patients revealed important group differences. Distinct neurocognitive and clinical profiles were observed."
"Students with ADD/noH, however, had significantly lower scores on the Calculation subtest compared to all of the other achievement subtests. These results provided additional support for the hypothesis that inattention exerts a specific and deleterious effect on the acquisition of arithmetic computation skills"
"The patient groups were found to have greater levels of theta and deficiencies of alpha and beta in comparison to the control group. Children with Attention-Deficit/Hyperactivity Disorder of the Predominantly Inattentive type were found to be significantly different from those of the Combined type in the same measures, appearing to be closer to the normal profiles."
"Discriminant analysis does not suggest a strong advantage of either measure in differentiating children with ADHD from those who do not meet criteria for ADHD, except for the BASC TRS which has better predictive ability for children who do not meet ADHD criteria. For subtypes of ADHD, and specifically the ADHD: Predominantly Inattentive subtype, however, results would favor the use of the BASC PRS and TRS."
"Validity of DSM-IV ADHD predominantly inattentive and combined types: relationship to previous DSM diagnoses/subtype differences. Results support a multidimensional conceptualization of ADHD. There exists close correspondence between the DSM-III ADD/WO type and the DSM-IV predominantly inattentive type and between the DSM-III ADD/H type and the DSM-IV combined type."