To evaluate and compare a focused set of component neuropsychological executive functions in the DSM-IV attention-deficit/hyperactivity disorder combined (ADHD-C) and inattentive (ADHD-I) subtypes.
...The Stop task, Tower of London, Stroop task, Trailmaking Test, and output speed measures were completed by 105 boys and girls aged 7-12 classified as either DSM-IV ADHD-C (n = 46), ADHD-I (n = 18), or community control (n = 41).
Both subtypes had deficits on output speed. A group x gender interaction was observed on the Stop task: boys with ADHD-C were impaired versus boys with ADHD-I, whereas girls in the two subtypes did not differ. The ADHD-C type had a deficit in planning. Neither ADHD group had a deficit in interference control per se, although they were slower than controls on the Stroop tasks.
ADHD-I shares neuropsychological deficits with ADHD-C in the domain of output speed; on most domains the subtypes did not differ. Neuropsychological distinctions between these ADHD subtypes may be few, depending on which domain of executive functioning is assessed, and these distinctions differ by gender. In the case of boys, the two subtypes may be distinguished by the specificity of motor inhibition deficits to ADHD-C.
Background: Whether selective attention is a primary deficit in childhood Attention Deficit Hyperactivity Disorder (ADHD) remains in active debate.
Methods: We used the perceptual load paradigm to ...examine both early and late selective attention in children with the Primarily Inattentive (ADHD‐I) and Combined subtypes (ADHD‐C) of ADHD.
Results: No evidence emerged for selective attention deficits in either of the subtypes, but sluggish cognitive tempo was associated with abnormal early selection.
Conclusions: At least some, and possibly most, children with DSM‐IV ADHD have normal selective attention. Results support the move away from theories of attention dysfunction as primary in ADHD‐C. In ADHD‐I, this was one of the first formal tests of posterior attention network dysfunction, and results did not support that theory. However, ADHD children with sluggish cognitive tempo (SCT) warrant more study for possible early selective attention deficits.
Objective: This study evaluated the relationship between a family adversity index and DSM-IV attention-deficit/hyperactivity disorder (ADHD) subtypes and associated behavior problems. The ...relationship of family adversity to symptoms and subtypes of ADHD was examined. Method: Parents and 206 children aged 7-13 completed diagnostic interviews and rating scales about socioeconomic status, parental lifetime psychiatric disorders, marital conflict, and stressful life events. Results: Children with ADHD combined type experienced more risk factors than community controls (p = .002) or children with ADHD predominantly inattentive type (p = .02). The families of children with ADHD combined type described more risk factors associated with family adversity than the families of children with ADHD inattentive type and the control group. Parent-rated symptoms of child inattention/disorganization were related uniquely to the adversity index score independently of conduct disorder symptoms. Children's perceptions of marital conflict were independently related to inattention and hyperactivity behaviors as rated by parents and teachers after control of all other risk factors. Oppositional defiant symptoms were independently related to marital conflict and maternal psychopathology, whereas conduct disorder symptoms were uniquely related to low socioeconomic status and maternal psychopathology. Conclusions: Family adversity is related to ADHD combined type in children and may be related specifically to ADHD symptoms in addition to conduct disorder symptoms.
We review all 14 extant studies of covert visuospatial attention in attention deficit hyperactivity disorder (ADHD) (total
N=248). Metaanalysis showed that intriguing but isolated findings of ...alerting or posterior disengage deficits were too small to reliably detect with the sample sizes typically employed. Posterior move and engage operations and the vigilance sustained attention process were normal in ADHD. For exogenous cues, effect sizes for group differences were homogeneously small across all repeated-measures conditions, as were calculations of cost, benefit, and validity effects. For endogenous cues, effect sizes were heterogeneous; however, calculations of cost, benefit, and validity effects were small and homogenous. The most parsimonious conclusion may be that ADHD is not characterized by significant visual orienting dysfunction, but questions remain about the extent of anterior lateralized effects in the combined subtype and about attentional functioning in the inattentive subtype.
We review different conceptions of inhibitory control that may be relevant to the regulatory problems featured in borderline personality disorder (BPD). These conceptions have often been framed with ...regard to personality traits of inhibitory control, but can also be related to cognitive measures of response suppression as well as affect regulation. Reactive behavioral inhibition is relatively unstudied in relation to BPD. A substantial amount of literature links executive function problems with BPD, but that literature has not isolated executive response inhibition nor been controlled for other personality disorder symptoms of antisociality, attention-deficit/hyperactivity disorder (ADHD), or depression, anxiety, or posttraumatic symptoms. We therefore conducted a study of this question looking at BPD symptoms in an adult sample with a small number of BPD subjects and other disorders. Results indicated that symptoms of BPD were correlated with response inhibition (measured by stop signal reaction time) even after controlling for the overlap of stop inhibition with ADHD, antisociality, and other Axis II disorder symptoms. We conclude by hypothesizing discrete developmental routes to BPD, based on different mechanism breakdowns, which would be amenable to empirical investigation at the cognitive or trait level of analysis.
Gonadal hormones may exert permanent organizational effects on sexually dimorphic finger-length ratios and sexually dimorphic behavior expressed in childhood attention deficit-hyperactivity disorder ...(ADHD). This study extended recent work examining associations between finger-length ratios (specifically, 2D:4D) and ADHD in a well-characterized, clinically diagnosed, community-recruited sample of boys and girls. A multistage, diagnostic procedure was utilized to identify 113 children with ADHD and 137 non-ADHD comparison children. Right-hand digit ratios showed significant mean differences by gender, as well as associations with ADHD diagnosis. Boys with ADHD had more masculinized digit ratios than control-group boys. More masculine right 2D:4D and 3D:4D ratios were correlated with parent- and teacher-rated inattentive and hyperactive-impulsive symptoms in boys but not in girls. Masculinized finger-length ratios were associated with hyperactive-impulsive and oppositional-defiant symptoms, but associations were largest with symptoms of inattention. It is concluded that prenatal, organizational effects of gonadal hormones may play a role in the development of ADHD and contribute to explaining sex differences in the prevalence rates of this childhood disorder.
We report three related studies of covert visual spatial orienting in child attention deficit hyperactivity disorder (ADHD). In Study 1, we examined covert visual spatial orienting in ADHD and ...comparison boys, Study 2 comprised a dose–response study of methylphenidate for the ADHD group, and Study 3 was an investigation of biological and adoptive parents. In contrast with comparison subjects (n=17), ADHD boys aged 6–12 (n=27) showed both slower reaction times overall and within-condition (lateral) asymmetries in reaction times. Specifically, boys with ADHD reacted more slowly to uncued targets in the left visual field than in the right visual field. Responses to stimuli in the two visual fields were differentially affected by methylphenidate for the ADHD group. Medication equalized visual field responses to the uncued targets, resulting in a significant cue×dose×visual field interaction. Further, medication altered the relative cue responsivity in the two visual fields, resulting in a significant dose×visual field interaction for the Validity Effect. Biological parents of ADHD boys (n=16) also showed slower reaction times to uncued left visual field targets than to right visual field targets; in addition they showed slower response to invalidly cued targets in the right visual field. These lateral effects were not observed in adoptive parents of ADHD boys (n=12) or biological parents of comparison boys (n=14). Possible abnormal hemispheric asymmetry of attention functions in boys with ADHD and their biological parents is discussed.
Genetics of Personality Disorders Nigg, Joel T; Goldsmith, H. Hill
Psychological bulletin,
05/1994, Letnik:
115, Številka:
3
Journal Article
Recenzirano
Although the field is young, studies pertinent to genetic hypotheses have accumulated for several personality disorders. Genetic links to personality disorders from the domains of normal personality ...and Axis I disorders are reviewed. Evidence of a link to schizophrenia is clearest for schizotypal and less conclusive for paranoid and schizoid personality disorders. A genetic association between borderline personality disorder and affective disorders has not been clearly supported, but there may be a subtype genetically linked to affective disorders. Evidence of genetic influence is mixed for obsessive-compulsive personality disorder. In general, greater attention to dimensional phenotypic measures and multivariate designs can yield more definitive answers regarding the correct subtyping and probable etiology of personality disorders.
Although response inhibition has been proposed as a core element of child attention-deficit hyperactivity disorder (ADHD), the literature is heavily reliant on studies using DSM-III-R diagnostic ...criteria, older methods of measuring response inhibition, samples of boys, and failing to control thoroughly for comorbid problems--both as diagnoses and as subclinical variation. The present study replicated a deficit in response inhibition in the ADHD combined type (DSM-IV, American Psychiatric Association, 1994) using samples matched on age and sex. The study replicated an effect size of approximately d = .6 in boys with ADHD, and observed an even larger effect size for girls, although the Sex x Group interaction was nonsignificant. Children with ADHD also had problems with response output, shown by variable responding. Excluding comorbid conduct disorder, reading disorder, generalized anxiety disorder, obsessive-compulsive disorder, major depression, and posttraumatic stress disorder from the sample did not alter the results. Correlations indicated that response inhibition was associated with both attentional problems and reading level. Covarying for reading problems did not eliminate the ADHD group effect, but the association of response inhibition with reading clearly requires further examination. Overall, the study supported the role of response inhibition in the DSM-IV ADHD combined type, but with key qualifications as to degree of specificity in reference both to comorbid problems and other executive functions.
Fletcher, L., Cerniglia, G. J., Nigg, E. A., Yen, T. J. and Muschel, R. J. Inhibition of Centrosome Separation after DNA Damage: A Role for Nek2. Radiat. Res. 162, 128–135 (2004). DNA damage results ...in cell cycle arrest in G2. Centrosomes also separate in G2, raising the question of whether separation occurs during the DNA damage-induced G2 arrest. Nek2, the mammalian homologue of NIMA, is a cell cycle-regulated serine/threonine protein kinase that regulates centrosome separation during G2. Here we show that damaged cells fail to activate Nek2. Both Nek2 levels and activity are reduced after DNA damage. Radiation inhibits the premature centrosome splitting induced by overexpression of Nek2, indicating that Nek2 is involved in activation of the G2 checkpoint and is not secondary to cell cycle arrest. We confirm using siRNA that centrosome separation and cell growth are impaired in the absence of Nek2. These studies define a previously unreported DNA damage response of inhibition of centrosome separation mechanistically linked to Nek2.
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