Subjective and objective assessment of executive functions in Parkinson's disease

AbstractImpairments in executive functions (EF) in Parkinson's disease (PD) will have a negative influence on daily life. For the assessment objective and subjective measurement approaches are used. It is however unknown whether these approaches contribute in a different way to the assessment of EF in PD. Thirty-nine PD patients and 24 healthy participants completed the Dysexecutive questionnaire (DEX; subjective measure) and the Frontal Assessment Battery (FAB; objective measure). PD patients showed impaired EF (FAB) and reported more problems with EF in daily life (DEX) than healthy participants. The performance on the FAB could however not be explained by the problems with EF that were reported by PD patients (DEX) and vice versa. In conclusion, not all PD patients who show impairments in EF report them and not all PD patients who report problems with EF in daily life show impairments according to objective measurement. Both measures thus contribute in a different way to the assessment of EF in PD patients. However, it has to be considered that the FAB is not a critical test to assess cognition in PD, since these patients also suffer from posterior abnormalities including memory and visuo-spatial deficits which are strong predictors for PD dementia

The Development of an Embedded Figures Test for the Detection of Feigned Attention Deficit Hyperactivity Disorder in Adulthood

OBJECTIVES: It has been shown that an increasing number of adults deliberately feign attention deficit hyperactivity disorder (ADHD), which demonstrates the need for new tests designed to detect feigned ADHD. METHODS: An Embedded Figures Test (EFT) was developed for the detection of feigned ADHD in adulthood. EFT performance of 51 adults with ADHD was compared to the performance of 52 matched healthy individuals, as well as to 268 undergraduate students who were randomly allocated in a simulation design to one of four experimental conditions, i.e. a control group, a naïve simulation group, a symptom-coached simulation group or a test-coached simulation group. Furthermore, an independent sample of 11 adults with ADHD as well as a sample of 17 clinicians experienced in the work with adults with ADHD were assessed for further validation of the EFT. RESULTS: The EFT was relatively easy to perform for both patients with ADHD and healthy comparisons as shown by low error rates and non-significant group differences. However, simulation groups differed from patients with ADHD by significant and large effects. An EFT index for the prediction of feigned ADHD was derived based on logistic regression coefficients. Receiver Operating Characteristics (ROC) demonstrated good classification accuracy of feigned ADHD relative to ADHD (AUC = 94.8%), i.e. high sensitivity (88%) and specificity (90%). CONCLUSIONS: This study supports the utility of the EFT for the detection of feigned adult ADHD

Blink rate and blink timing in children with ADHD and the influence of stimulant medication

Spontaneous eye blink rate is modulated by task demands and internal state, and is demonstrated to reflect central dopamine activity. Also, spontaneous eye blinks are strategically timed around salient stimuli. This study investigates whether children with attention deficit hyperactivity disorder (ADHD) show reduced blink rates, blink modulation and blink timing, and whether this is influenced by stimulant medication. The electrooculogram was measured in 18 typically developing children, 16 children with ADHD off methylphenidate (Mph), and 16 children with ADHD on Mph during a rest period and during performance of a 60-min visual selective attention task. Blink rate and timing was extracted from the electrooculogram. No evidence was found for aberrant blink rate or blink modulation in children with ADHD off Mph. All groups increased blink rates from rest to task, and no group differences were found in blink rate during rest and task, or in the modulation of blink rate from rest to task. Time-on task resulted in a similar increase in blink rates in all three groups. Stimulant medication appeared not to influence blink rate and blink modulation, except that in the ADHD off Mph group the blink rate was enhanced only under conditions with performance feedback. All groups inhibited blinks before stimulus presentation and strategically timed their blinks after the stimulus. Children with ADHD off Mph showed reduced blink inhibition before the stimulus; however, given the low incidence (\1 % of the trials) and long latency this is not likely to impair their visual intake

Reduced emotional empathy in adults with subclinical ADHD:Evidence from the empathy and systemizing quotient

Studies in children with ADHD suggest impairments in social cognitive functions, whereas studies in adults with ADHD are scarce and inconclusive. The aim of this study was to investigate the relationship between ADHD traits and self-reported social cognitive style in a sample of adults from the general population. For this purpose, a community sample of 685 adults filled out online self-report questionnaires about ADHD symptoms (ADHD Rating Scale, ARS), social cognitive functioning and friendships. The Empathy Quotient (EQ) with the subscales Cognitive Empathy (CE), Emotional Empathy (EE) and Social Skills (SS), and the Systemizing Quotient (SQ) were included for measuring social cognitive style and the Friendship Questionnaire (FQ) for the quality of friendships. Participants who met the DSM-5 criteria on the ARS ('subclinical ADHD'; n = 56) were compared regarding their social cognitive functioning scores with a control group (n = 56) that was matched for age, sex and student status. With small effect sizes, the subclinical ADHD group showed reduced EE scores on the EQ and a more male social cognitive profile. This result was not influenced by sex or ADHD subtype. This study points to a relationship between traits of ADHD and the emotional aspect of empathy, whereas more complex aspects of empathy were unrelated. These findings should be corroborated in clinical patients with ADHD, employing neuropsychological tests rather than self-report questionnaires

Effects of DSP4 and methylphenidate on spatial memory performance in rats

In this experiment, we have investigated the spatial memory performance of rats following a central noradrenaline depletion induced by three different doses of the neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4) and following administration of three different doses of methylphenidate (MPH). The rats were required to find food pellets hidden on a holeboard. The sole administration of DSP4 induced only minor cognitive deficits. However, the treatment with MPH increased the reference memory error, the impulsivity and the motor activity of the DSP4-treated rats. Since the noradrenergic terminals in a DSP4-treated rat are significantly reduced, the administration of MPH has little effect on the noradrenergic system and increases dopaminergic rather than noradrenergic activity, resulting in an imbalance with relatively high dopaminergic and low noradrenergic activities. It is suggested that a reduction of noradrenaline and an increase of dopamine induce ADHD-related deficits and that the depletion of noradrenaline is not sufficient for an appropriate rat model of ADHD

[poster on] Are traits of ADHD associated with self-reported social cognition in an adult community sample?

Introduction: Studies in children with ADHD suggest impairments in social cognitive functions, whereas studies in adults with ADHD are lacking. Objectives: The first aim was to investigate the relationship between self-reported social cognition and ADHD traits in a normal population (dimensional approach). The second aim was to investigate whether participants with a screening diagnosis (DSM-5 criteria) differ from matched controls in their reports of social cognition (categorical approach). Methods: A community sample of 685 respondents was surveyed online, including the ADHD Rating Scale (ARS). The Empathy Quotient (EQ) with the subscales Cognitive Empathy (CE), Emotional Empathy (EE), and Social Skills (SS), and the Systemizing Quotient (SQ) were included for measuring social cognition. In the dimensional approach, multiple regression was used to investigate whether social cognition measures predicted ADHD traits. In the categorical approach participants with an ARS screening diagnosis of ADHD (n = 109) were compared to matched controls on the social cognition scores. Results: Dimensional approach: Subscales SS and EE significantly predicted ADHD traits (8.5% explained variance). In males, only SS predicted ADHD traits, whereas in females both variables contributed to the model. Categorical approach: With small effect sizes, the female ADHD group had reduced EQ scores, enlarged SQ scores, and a more male brain type than their matched controls. No differences were found for males. Discussion: Both the dimensional and categorical approach revealed a small but significant relationship between social cognition and ADHD traits in adults. This relationship depends on gender and is more prominent in females