Perceived stress in prodromal Huntington disease

This study examines perceived stress and its relationship to depressive symptoms, life changes and functional capacity in a large sample of individuals who are positive for the Huntington disease (HD) gene expansion but not yet diagnosed. Participants were classified by estimated proximity to HD diagnosis (far, mid, near) and compared with a non-gene-expanded comparison group. Persons in the mid group had the highest stress scores. A significant interaction between age and time since HD genetic testing was also found. Secondary analyses using data from a different data collection point and including a diagnosed group showed the highest stress scores in the diagnosed group. Possible explanations and implications are discussed.     

The Visual Spatial Learning Test: Differential impairment during the premanifest and manifest stages of Huntington's disease

Visual spatial memory was assessed using the Visual Spatial Learning Test (VSLT) in individuals with mild to moderate Huntington's disease (HD), pre‐manifest gene carriers for HD, and demographically similar controls. The VSLT has been demonstrated to be a valid, normed measure of non‐verbal memory involving minimal motoric responses. The VSLT assesses immediate and delayed memory for designs, positions of the designs, and design/position associations. The HD group was significantly impaired (p < .05) relative to both the control and Pre‐HD groups on immediate and delayed memory for the designs, positions, and design/position associations. Although there were no differences between the Pre‐HD and control groups on immediate or delayed memory for designs or positions, the Pre‐HD group was significantly impaired (p < .05) relative to the control group on immediate and delayed memory for design/position associations. The results offer novel insight into a relatively unexamined memory deficit that may occur in gene carriers for HD prior to phenoconversion. The data indicate that the VSLT may be a useful measure of visuospatial memory during the premanifest and manifest stages of HD.     

Delta plots in the study of individual differences: new tools reveal response inhibition deficits in AD/Hd that are eliminated by methylphenidate treatment

The authors highlight the utility of distribution-analytical techniques in the study of individual differences and clinical disorders. Cognitive deficits associated with attention-deficit/hyperactivity disorder (AD/HD) were examined by using delta-plot analyses of performance data (reaction time and accuracy) obtained through the use of a prototypical conflict task, the Eriksen flanker task. In 20 children with AD/HD (compared with matched control participants), overall performance measures indicated a marginal performance deficit. Delta-plot analyses indicated that performance deficits associated with AD/HD involve response inhibition but not automatic response activation. In a within-subjects titration study, the response inhibition deficit was eliminated by methylphenidate treatment, but these effects were highly dose specific. The beneficial effect of methylphenidate was clarified further after correcting for inter-individual variation in sensitivity to medicine dosage.     

Chronic stress, but not hypercaloric diet, impairs vascular function in rats

The aim of this study was to evaluate vascular and metabolic effects of chronic mild unpredictable stress (CMS) and hypercaloric diet (HD) without carbohydrate supplementation in rats. Male Sprague-Dawley rats were randomly assigned to four groups: Control, HD, CMS, and HD plus CMS. CMS consisted of the application of different stressors for 3 weeks. The rats were killed 15 days after CMS exposure. The HD group presented higher plasma lipid concentrations, without changes in fasting glucose concentration, glucose tolerance test, and vascular function and morphology, in comparison with the control group. Stressed rats presented higher fasting blood concentration of insulin, higher homeostasis model assessment index values and area under the curve in an oral glucose tolerance test, in comparison with non-stressed rats. CMS increased the plasma concentrations of corticosterone and lipids, and the atherogenic index values, without change in high-density lipoprotein level. CMS increased intima-media thickness and induced endothelium-dependent supersensitivity to phenylephrine, and lowered the relaxation response to acetylcholine in the thoracic aorta isolated from rats fed with control or HD, in comparison with non-stressed groups. CMS effects were independent of diet. In non-stressed rats, the HD induced dyslipidemia, but did not change glucose metabolism, vascular function, or morphology. The data from this study indicate that CMS promotes a set of events which together can contribute to impair function of the thoracic aorta.     

Discovering the Family History of Huntington Disease (HD)

A considerable body of research has explored both predictive genetic test decisions for Huntington disease (HD) and the impact of receiving a test result. Extant research reveals little, however, about how and when at risk persons first discover their family history of HD. Drawing upon 24 semi-structured interviews with at risk persons and their family members, this study explored initial discovery of HD in the family. Qualitative data analysis revealed four different, though sometimes related, trajectories of discovery: (1) something is wrong, (2) out of the blue, (3) knowing, but dismissing, and 4) growing up with HD. These pathways highlighted the importance of the temporal and historical contexts in which genetic risk for HD was discovered. Notably, ignorance about HD was the most salient feature shaping participants' narratives of discovery. Implications for research and clinical practice are discussed.     

Which Executive Functioning Deficits Are Associated With AD/HD,ODD/CD and Comorbid AD/HD+ODD/CD?

This study investigated (1) whether attention deficit/hyperactivity disorder (AD/HD) is associated with executive functioning (EF) deficits while controlling for oppositional defiant disorder/conduct disorder (ODD/CD), (2) whether ODD/CD is associated with EF deficits while controlling for AD/HD, and (3)~whether a combination of AD/HD and ODD/CD is associated with EF deficits (and the possibility that there is no association between EF deficits and AD/HD or ODD/CD in isolation). Subjects were 99~children ages 6–12 years. Three putative domains of EF were investigated using well-validated tests: verbal fluency, working memory, and planning. Independent of ODD/CD, AD/HD was associated with deficits in planning and working memory, but not in verbal fluency. Only teacher rated AD/HD, but not parent rated AD/HD, significantly contributed to the prediction of EF task performance. No EF deficits were associated with ODD/CD. The presence of comorbid AD/HD accounts for the EF deficits in children with comorbid AD/HD+ODD/CD. These results suggest that EF deficits are unique to AD/HD and support the model proposed by R. A. Barkley (1997).     

The Role of Intrusive Imagery in Hoarding Disorder

Despite the incidence of trauma in the histories of people with Hoarding Disorder (HD), reexperiencing symptoms, namely intrusive images, have not been investigated in the condition. To address this, 27 individuals who met DSM-5 criteria for HD and 28 community controls (CCs) were interviewed about (a) their everyday experiences of intrusive imagery, and (b) the unexpected images they experience when discarding high- and low-value possessions. Compared to CCs, everyday images described by the HD group were more frequent, had a greater negative valence, and were associated with greater interference in everyday life and attempts to avoid the imagery. With regard to discard-related imagery, a MANOVA followed up with mixed ANOVAs showed that HD participants reported more negative experiences of intrusive imagery in comparison with CCs during recent episodes of discarding objects of low subjective value. However, HD and CC participants both experienced positive imagery when discarding high-value objects. CC participants reported greater avoidance of imagery in the high-value object condition, but imagery-avoidance did not change between conditions for HD participants. The findings are discussed, particularly in relation to the potential of imagery-based interventions for HD.     

Further analysis of encoding in patients with Huntington's disease

Arguments favoring the view that derangement of normal encoding processes contributes to the memory defects of patients with Huntington's disease (HD) are supported by the finding that HD patients do not learn highly imageable words more rapidly than they learn words that are difficult to image. But other data indicating that HD patients can use verbal mediators as mnemonic aids for picture recognition question the existence of important and general encoding deficits in HD. In the first of two experiments the influence of imagery on the acquisition and recall of 14-word lists was studied using a free-recall paradigm. Both HD patients and controls learned highly imageable words more quickly and retained them better than low imagery words over a 30-min delay. The impact of imagery on learning was apparent by the first trial. In the second experiment, a modified Brown-Peterson distractor paradigm was used to assess release from proactive interference (PI). It was found that both HD patients and controls exhibited comparable release from PI following a shift in taxonomic categories. The results of both experiments question the importance of encoding deficits in the memorial dysfunctions associated with HD.     

Characteristic patterns of verbal memory function in patients with Huntington's disease

Various aspects of verbal memory in patients with Huntington's disease (HD) were studied using the California Verbal Learning Test (CVLT). We tested if the level and interplay between 5 parameters of different memory mechanisms and processes were sufficiently specific to allow acceptable discrimination between patients with HD, patients with Parkinson's disease (PD), and patients without known CNS disease or injury. The HD-patients were characterized by a deficit in acquisition, elevated rates of recall errors and increased use of a passive learning strategy. Preserved aspects were shown in retention over time, interference effects and recognition relative to recall. Employing multivariate classification and validation techniques, the 5 CVLT-features demonstrated good separability between the HD-patients and the control patients. Qualitative similarities between subgroups were suggested, but more disease-specific data seemed necessary in further studies. A number of findings suggested a defect in the active organization of items to be encoded and recalled in HD. Similar findings in the PD-group might indicate that this trait is common in several types of 'subcortical dementia'.     

An Exploration of the Experience of Huntington’s Disease in Family Dyads: An Interpretative Phenomenological Analysis

Huntington’s disease (HD) is a hereditary, late onset, neurodegenerative disorder. Children of affected parents have a 50 % chance of inheriting HD. Research into the psychological consequences of HD for the family has focussed on individual family members, but little is known about the ways in which its impact is jointly experienced by members of these families. This is particularly important due to the hereditary nature of HD. To address this, the current study examined the experiences of dyads within affected families. Seven parent/adult child dyads were interviewed jointly about their experiences and relationships with their family and each other and interpretative phenomenological analysis was used to analyse the resultant data. Identified themes were: “A spectre hanging over us”: HD as a presence within the family, “Us against the world”: Protection, knowledge and control, and “That could be me in 50 years”: Cyclical changes in identity and role. These findings are examined in relation to previous research and indicate the need for an increased understanding of the needs of HD families. Clinical implications and suggestions for further research are discussed.     

Elementary school students with AD/HD: predictors of academic achievement

Academic underachievement frequently is associated with attention-deficit/hyperactivity disorder (AD/HD); however, the role of variables beyond AD/HD symptoms and cognitive mediators is unknown. Further, whether prediction models vary (a) relative to non-AD/HD students, (b) between math and reading, and (c) based on how achievement is defined has not been examined. Multiple measures (e.g., teacher ratings and behavior observations) were examined as predictors for concurrent achievement outcomes (standardized achievement test scores and report card grades) in math and reading in two samples of 1st through 4th grade children (136 with AD/HD, 53 without AD/HD). Teacher perceptions of academic skills were the strongest predictors of achievement test scores for both groups, while academic skills and enablers accounted for reading report card grades in children with AD/HD but not their normal counterparts. Implications of these findings for school-based assessment and intervention for students with AD/HD are discussed.     

Obtaining Systematic Teacher Reports of Disruptive Behavior Disorders Utilizing DSM-IV

This study examines the psychometric properties of the Vanderbilt AD/HD Diagnostic Teacher Rating Scale (VADTRS) and provides preliminary normative data from a large, geographically defined population. The VADTRS consists of the complete list of DSM-IV AD/HD symptoms, a screen for other disruptive behavior disorders, anxiety and depression, and ratings of academic and classroom behavior performance. Teachers in one suburban county completed the scale for their students during 2 consecutive years. Statistical methods included (a) exploratory and confirmatory latent variable analyses of item data, (b) evaluation of the internal consistency of the latent dimensions, (c) evaluation of latent structure concordance between school year samples, and (d) preliminary evaluation of criterion-related validity. The instrument comprises four behavioral dimensions and two performance dimensions. The behavioral dimensions were concordant between school years and were consistent with a priori DSM-IV diagnostic criteria. Correlations between latent dimensions and relevant, known disorders or problems varied from .25 to .66.     

AD/HD Symptoms and Conduct Problems: Similarities and Differences in Maternal Perceptions

Several theories attempt to explain the high co-occurrence of Attention Deficit/ Hyperactivity Disorder (AD/HD) and Conduct Problems (CP). A strong possibility is that AD/HD behaviours lead to the development of CP, due to family coercive interaction patterns, maintained through parental false beliefs regarding child problem behaviour. We compared maternal perceptions about AD/HD behaviors and CP, and the possible reactions elicited by such behaviours. The sample consisted of 317 mothers of boys and girls aged 4–6. Four versions of The Parental Account of the Causes of Childhood Problems Questionnaire were used, in which a vignette was ascribed to either a boy or a girl displaying some of the major AD/HD behaviours or CP. The results showed that CP were perceived as significantly more severe than AD/HD behaviours. Moreover, AD/HD behaviours were attributed to biological causes more often than CP, and less strict rearing practices were chosen for AD/HD symptoms. Our findings provide evidence that mothers usually perceive AD/HD behaviours and CP as separate entities and may behave accordingly with their children.     

Prevalence of Attention-Deficit/Hyperactivity Disorder Symptoms in 4- to 17-Year-Old Children in the General Population

The purposes of this study were (a) to estimate the prevalence of Attention-Deficit/Hyperactivity Disorder (AD/HD) symptoms in the general preschool and school population; and (b) to analyze the influence of gender, age, and socioeconomic status (SES) variables on AD/HD symptoms. Out of the 80,000 preschool and schoolchildren living in Manizales, Colombia, a random sample of 540 children was selected. Two gender, three age (4- to 5-year olds, 6- to 11 -year olds, and 12- to 17-year olds), and three SES (low, middle, and high) groups were used. The 18 DSM-IV symptoms corresponding to AD/HD Criterion A were assessed on a scale of 0 (never) to 3 (almost always). All three demographic variables established statistically significant differences: AD/HD symptoms were more frequent in 6-to 11-year-old, low-SES, male participants. DSM-IV Criterion A for AD/HD was fulfilled by 19.8% of the boys and 12.3% of the girls. However, this difference was marginally significant only in the AD/HD Subtype I: Combined. It was concluded that demographic variables are significant correlates of the AD/HD diagnosis. The prevalence found in this study was higher than usually reported, even though only the symptomatic DSM-IV AD/HD criterion was analyzed. We failed to confirm the assumed AD/HD gender ratio.     

Productive syntax abilities in Huntington's and Parkinson's diseases

This study examined syntactic changes in the spoken discourse of patients with Huntington's (HD) or Parkinson's disease (PD) and explored possible relationships between their syntactic changes and concomitant cognitive and motoric symptoms. Patient and control groups participated in a conversational discourse activity and completed a battery of standardized speech and cognitive tests. The HD group used shorter and fewer grammatically complete utterances than their healthy, age-matched peers, whereas there were no significant syntactic differences between PD patients and their healthy, age-matched peers or between PD and HD patients. Productive syntax abilities in HD and PD were meaningfully related to both neuropsychological and motor speech changes. These findings indicate that patients with subcortical disease, at least those with HD, may present with language production deficits and that these deficits are most likely the product of not only motor speech limitations (i.e., dysarthria) but also underlying cognitive impairments.     

Evaluation of a cognitive-behavioural program for the management of chronic tic and habit disorders

The aim was to evaluate the efficacy of a manualized cognitive-behavioural program based on habit reversal for the management of chronic tic disorder (CTD) and habit disorder (HD). Forty-seven CTD and 43 HD received a 4-month treatment program. Thirty-eight (22 CTD, 16 HD) were placed on a waitlist control group, which subsequently received treatment. The treatment approach combined awareness training, relaxation (including modification of a tension-producing style of action), and habit-reversal training, with more general cognitive restructuring of anticipations linked to ticcing. Sixty-five percent of completers reported between 75 and 100% control over the tic. At 2-year follow-up, 52% rated 75-100% control. There were also significant changes post-treatment in measures of self-esteem, anxiety, depression and style of planning action. Successful tic/habit modification was associated in CTD and HD groups with successful change in style of planning action. There were no consistent differences in any outcome measures between CTD and HD groups.     

Response Inhibition in Children With DSM-IV Subtypes of AD/HD and Related Disruptive Disorders: The Role of Reward

The current study had four aims: (a) to replicate previous findings of slow response inhibition in Attention Deficit/Hyperactivity Disorder (AD/HD), (b) to explore whether poor response inhibition in children with AD/HD is a core problem or rather a result of an underlying problem related to reward, (c) to investigate the specificity of poor response inhibition and the role of reward in relation to AD/HD, and (d) to study whether findings would be different for three subtypes of AD/HD. In order to address these issues, a stop paradigm was administered under a reward condition and under a nonreward condition to an AD/HD group (n = 24), an Oppositional Defiant Disorder (ODD)/Conduct Disorder (CD) group (n = 21), a comorbid AD/HD+ODD/ CD group (n = 27), and a normal control (NC) group (n = 41). Firstly, contrary to prediction, none of the Disruptive Behavior Disorder (DBD) groups differed from the NC group with respect to the speed of the inhibition process. Secondly, it was shown that children with AD/HD and children with comorbid AD/HD+ODD/CD, but not children with ODD/CD alone, slowed down more dramatically in the reward condition than normal controls. This finding was interpreted as a strategy to increase the chance of being rewarded in children with AD/HD and children with comorbid AD/HD+ODD/CD, but not in children with pure ODD/CD. Finally, analysis of AD/HD subtypes did not change the main findings of this study.     

Response inhibition in children with DSM-IV subtypes of AD/HD and related disruptive disorders: the role of reward.

The current study had four aims: (a) to replicate previous findings of slow response inhibition in Attention Deficit/Hyperactivity Disorder (AD/HD), (b) to explore whether poor response inhibition in children with AD/HD is a core problem or rather a result of an underlying problem related to reward, (c) to investigate the specificity of poor response inhibition and the role of reward in relation to AD/HD, and (d) to study whether findings would be different for three subtypes of AD/HD. In order to address these issues, a stop paradigm was administered under a reward condition and under a nonreward condition to an AD/HD group (n=24), an Oppositional Defiant Disorder (ODD)/Conduct Disorder (CD) group (n=21), a comorbid AD/HD+ODD/CD group (n=27), and a normal control (NC) group (n=41). Firstly, contrary to prediction, none of the Disruptive Behavior Disorder (DBD) groups differed from the NC group with respect to the speed of the inhibition process. Secondly, it was shown that children with AD/HD and children with comorbid AD/HD+ODD/CD, but not children with ODD/CD alone, slowed down more dramatically in the reward condition than normal controls. This finding was interpreted as a strategy to increase the chance of being rewarded in children with AD/HD and children with comorbid AD/HD+ODD/CD, but not in children with pure ODD/CD. Finally, analysis of AD/HD subtypes did not change the main findings of this study.     

A comparison of the category fluency deficits associated with Alzheimer's and Huntington's disease

The supermarket verbal fluency test of the Dementia Rating Scale (DRS) was administered to 20 patients with mild Alzheimer's disease (Mi-DAT), 20 patients with moderately severe Alzheimer's disease (Mo-DAT), 20 patients with Huntington's disease (HD), and 40 normal control subjects. The findings confirmed previous reports that Mo-DAT patients retrieved fewer words per category of supermarket items sampled and had a greater propensity to generate category labels (superordinates) than did intact controls. Similar disruptions of the structure of semantic knowledge were also noted in the fluency performances of the Mi-DAT and HD patients. The Mi-DAT patients' tendency to generate few exemplars for each category sampled suggested that a significant disruption in the structure of semantic knowledge occurred even in the earliest stages of DAT. When the present fluency findings for the HD patients were considered with previous reports of linguistic changes in this disorder, it appeared that HD patients' deterioration in semantic knowledge involved associative changes rather than the bottom-up breakdown associated with DAT.