Postural instability in Parkinson’s disease assessed with clinical “pull test” and standardized postural perturbations: effect of medication and body weight support

Journal of Neurology - This experiment tested if balance performance differed between a standardized treadmill surface perturbation task and a clinical pull test and was affected by medication or...     

Advantages of timing the duration of a freezing of gait-provoking test in individuals with Parkinson’s disease

Journal of Neurology - Evaluating freezing of gait (FOG) and quantifying its severity in patients with Parkinson’s disease (PD) is challenging; objective assessment is not sufficiently...     

Assessment of memory skills in illiterates: strategy differences or test artifact?

Previous studies have reported that illiterates perform more poorly than literates on a variety of neuropsychological measures. We investigated the hypothesis that putative memory deficits in illiterates are an artifact of the assessment tools used rather than a reflection of an 'underdeveloped' ability. In order to accomplish this, we designed two tests, a word list learning test and an object learning test. The illiterate group performed more poorly than semiliterate and literate groups on most variables of the word list learning test, but only on delayed recall and semantic clustering on the object learning test. Our findings suggest that poor memory performance among illiterates can be attributed both to the nature of the task, as well as to the use of different cognitive mechanisms to recall learned information. Presumably, formal education may enhance the innate ability of learning through training individuals in efficient learning and retrieval strategies. We emphasize the importance of developing and using ecologically valid neuropsychological tests to assess illiterate individuals.     

An evaluation of multiple‐choice test images for comprehension assessment in aphasia

Background: Using images in multiple‐choice formats for comprehension testing in aphasia is common. It is generally assumed that persons being assessed perceive the content of the images represented in such tasks. However, specific visual characteristics of individual images may influence visual attention, which may influence accuracy in the selection of a correct target image corresponding to a verbal stimulus. The validity of test responses may be confounded by (1) physical stimulus features, such as size, and (2) semantic content conveyed by images, such as image familiarity.

Aims: The first aim was to develop a rating instrument to assess visual stimulus properties and semantic content conveyance in multiple‐choice images, based on an extensive review of empirical literature and validated by experts in graphic design. The second aim was to study the degree of relationship between viewers' subjective ratings of images selected from published aphasia batteries, using the rating instrument, and eye movement measures recorded as independent viewers looked at the same images. The third aim was to compare the viewers' actual eye movement indices of disproportionate visual attention to an ideal value of evenly proportionate visual attention for each image set.

Methods & Procedures: A rating instrument, based on an extensive review of literature and assessed and revised by graphic design and eye‐tracking experts, was developed to identify such influences within multiple‐choice images and was assessed through empirical testing of viewers' eye movement patterns as they looked at images from published aphasia tests. A total of 20 adults rated 20 image sets from five aphasia batteries. Eye movements were recorded for a separate group of 40 adults viewing the same images.

Outcomes & Results: Ratings were not statistically correlated with eye movement responses. All multiple‐choice image sets prompted significantly disproportionate visual attention.

Conclusions: Results highlight the importance of: (1) considering the possible influence of visual stimulus confounds on any given patient's test performance, and (2) better controlled image design for multiple‐choice test images to improve the validity of assessment. Further research is needed to improve subjective and objective means of assessment of images and guidelines for improved design of multiple‐choice image displays.     

Spinocerebellar ataxia in Singapore: predictive features of a positive DNA test?

Significant differences in frequency of the different spinocerebellar ataxia (SCA) subtypes have been described to occur in different populations. A 'blunderbuss' diagnostic DNA testing approach would entail unnecessary healthcare cost. In this study, we determine the prevalence of SCA subtypes and predictive features of a positive DNA test in consecutive clinically diagnosed SCA cases in Singapore. Twenty-one consecutive patients from 14 families were evaluated over a 3-year period. Thirteen patients (61.9%) from 6 families had a positive DNA test. Eleven of these (all ethnic Chinese) had SCA 3 (abnormal CAG size ranged from 61 to 71), and 2 ethnic Malays had SCA 2 (abnormal CAG size of 39). Clinical features which were highly predictive of a positive DNA SCA test in our population included presence of a positive family history, chorea and dystonia, muscle and tongue fasciculations, gaze-evoked nystagmus, and hypertonia. Our study draws attention to the observation that knowledge of relatively specific features of the most common SCA subtype in a local population can greatly enhance the practical accuracy of the choice of which SCA DNA test to order.     

1 year test–retest reliability of ImPACT in professional ice hockey players

The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery is widely used to assess neurocognitive outcomes following sports-related concussion. The purpose of this study was to examine the 1 year test–retest reliability of ImPACT in a multilingual sample of professional hockey players. A total of 305 professional hockey players were tested 1 year apart using ImPACT. Reliable change confidence intervals were calculated and test–retest reliability was measured using Pearson and Intraclass correlation coefficients. Results indicated that the 1-year test–retest reliabilities for the Visual Motor and Reaction Time Composites ranged from low to high (.52 to .81). In contrast, 1-year test–retest reliabilities for the Verbal and Visual Memory Composites were low (.22 to .58). The 1-year test–retest results provided mixed support for the use of Visual Motor and Reaction Time Composites in select samples; in contrast, the Verbal and Visual Memory Composites may not be sensitive to clinical change.     

Lack of NMDA–AMPA interaction in antidepressant-like effect of CGP 37849, an antagonist of NMDA receptor,in the forced swim test

The NMDA receptor antagonist, CGP 37849-induced reduction in immobility time in the forced swim test in mice was not antagonized by pre-treatment with the AMPA receptor antagonist NBQX. This is the first demonstration of the antidepressant effect of the NMDA antagonist not being dependent on the AMPA transmission.     

Development of a test battery for assessing phonological awareness in German‐speaking children

The development of phonological awareness (PA), the ability to reflect on the sound structure of words independent of their meaning, has been extensively explored in English‐speaking children. However, this is not the case for other languages. The aim of this study was to develop a comprehensive PA test battery for German‐speaking preschool children, considering psycholinguistic, linguistic, and cognitive aspects and to carry out analyses of its psychometric properties. Cross‐sectional data from a sample of 55 children (CA 4;0–6;11 years) were collected. Preliminary findings confirm validity and reliability of the test battery, and support previous findings that PA develops from larger to smaller linguistic units. Phoneme‐level tasks were consistently associated with letter knowledge. The new instrument is a promising tool for basic research (e.g. cross‐linguistic comparisons of PA development) as well as for clinical and educational practice (e.g. planning speech and language therapy or literacy‐oriented intervention).     

The clinical significance of 10-m walk test standardizations in Parkinson’s disease

Background

The 10-m walk test (10MWT) is a widely used measure of gait speed in Parkinson’s disease (PD). However, it is unclear if different standardizations of its conduct impact test results.

Aim of the study

We examined the clinical significance of two aspects of the standardization of the 10MWT in mild PD: static vs. dynamic start, and a single vs. repeated trials. Implications for fall prediction were also explored.

Methods

151 people with PD (mean age and PD duration, 68 and 4 years, respectively) completed the 10MWT in comfortable gait speed with static and dynamic start (two trials each), and gait speed (m/s) was recorded. Participants then registered all prospective falls for 6 months.

Results

Absolute mean differences between outcomes from the various test conditions ranged between 0.016 and 0.040 m/s (effect sizes, 0.06–0.14) with high levels of agreement (intra-class correlation coefficients, 0.932–0.987) and small standard errors of measurement (0.032–0.076 m/s). Receiver operating characteristic curves showed similar discriminate abilities for prediction of future falls across conditions (areas under curves, 0.70–0.73). Cut-off points were estimated at 1.1–1.2 m/s.

Conclusions

Different 10MWT standardizations yield very similar results, suggesting that there is no practical need for an acceleration distance or repeated trials when conducting this test in mild PD.

     

Contribution of auditory P300 test to the diagnosis of mild cognitive impairment in Parkinson’s disease

Abnormalities in auditory P300 test have been observed in patients with Parkinson’s disease (PD). We aimed to investigate whether or not additional electrophysiological tests assist in making the clinical diagnosis of mild cognitive impairment in Parkinson’s disease (PD-MCI), and we evaluated P300 changes in patients with non-demented PD and analyzed the correlation between the cognitive features and P300 changes. Twenty patients with PD who had been diagnosed with mild cognitive impairment (PD-MCI group) according to the Movement Disorder Society (MDS) 2012 PD-MCI level II criteria, 21 patients with PD without cognitive impairment (PD-Normal group), and 20 control subjects (control group) who were neurologically normal were examined by the standard auditory oddball paradigm. The N100, P200, N200, and P300 latencies and N100-P200, P200-N200, and N200-P300 amplitudes were measured and analyzed. P300 latencies recorded from Fz, Cz, and Pz and N200 latency recorded from Fz were significantly longer in the PD-MCI group than in the PD-Normal and the control group (respectively p < 0.001, p = 0.041). P300 amplitude recorded from Fz was significantly lower in PD-MCI group than those in the other groups (p = 0.038). While P300 was obtained in all patients in the PD-Normal and the control group, it was lost in 35% of PD-MCI patients. The results show that P300 provides a diagnostic tool for detecting PDMCI. We suggest that P300 prolongation and loss of P300 potential could be used as supportive parameter in the diagnosis of PD-MCI.     

What's in a voice? Prosody as a test case for the Theory of Mind account of autism

The human voice conveys a variety of information about people's feelings, emotions and mental states. Some of this information relies on sophisticated Theory of Mind (ToM) skills, whilst others are simpler and do not require ToM. This variety provides an interesting test case for the ToM account of autism, which would predict greater impairment as ToM requirements increase. In this paper, we draw on psychological and pragmatic theories to classify vocal cues according to the amount of mindreading required to identify them. Children with a high functioning Autism Spectrum Disorder and matched controls were tested in three experiments where the speakers’ state had to be extracted from their vocalizations. Although our results confirm that people with autism have subtle difficulties dealing with vocal cues, they show a pattern of performance that is inconsistent with the view that atypical recognition of vocal cues is caused by impaired ToM.     

Does the presence of anxiety affect the validity of a screening test for depression in the elderly?

INTRODUCTION: Depression in the elderly is frequently detected by screening instruments and often accompanied by anxiety. We set out to study if anxiety will affect the ability to detect depression by a screening instrument. OBJECTIVE: To validate the short Zung depression rating scale in Israeli elderly and to study the affect of anxiety on its validity. DESIGN: The short Zung was validated against a psychiatric evaluation, in a geriatric inpatient and outpatient service. The overall validity was determined, as well as for subgroups of sufferers and non-sufferers of anxiety. SETTING: An urban geriatric service in Israel. PATIENTS: 150 medical inpatients and outpatients, aged 70 years and older.MEASURES: Psychiatric evaluation of modified Anxiety Disorders Interview Schedule for DSM-IV as criterion standard for anxiety and depression and short Zung instrument for depression. RESULTS: By criterion validity, 60% suffered from depression. The overall validity of the short Zung was high (sensitivity 71.1%, specificity 88.3%, PPV 90.1%, NPV 67.1%). The validity for those not suffering from anxiety was good (sensitivity 71.1%, specificity 90.2%, PPV 84.4%, NPV 80.7%). In those with anxiety, sensitivity, specificity and PPV were high (71.2%, 77.8%, 94.9% respectively), although the specificity was less than in non-suffers. However major difference was in the NPV rate being much lower (31.8%). CONCLUSION: The short Zung, an easily administered instrument for detecting depression, is also valid in the Israeli elderly. However, anxiety limits the usefulness of this instrument in correctly ruling out depression. The clinician must be aware, therefore, that those suffering from anxiety may score negatively for depression on a screening instrument, such as the short Zung.     

Post-intubation pulmonary function test in Guillain-Barré syndrome

The value of daily postintubation respiratory function tests in predicting duration of ventilation in 37 mechanically ventilated patients with Guillain-Barré syndrome (GBS) was studied. Patients ventilated for less than 3 weeks were compared with those ventilated more than 3 weeks. Daily vital capacity and maximal inspiratory and expiratory pressures were summed to an integrated pulmonary function (PF) score. We calculated the PF ratio, which represents the PF score at day 12 after intubation divided by the PF score on the day of intubation. The PF ratio was greater than 1 in all 10 patients ventilated less than 3 weeks and was less than 1 in 19 of 27 patients ventilated for longer (P = 0.0001, Fisher exact test). The sensitivity of a PF ratio less than 1 for predicting duration of ventilation greater than 3 weeks was 70%; the specificity and positive predictive value were 100%. This study thus suggests that serial postintubation respiratory tests can provide a measure of respiratory status in patients with GBS. These parameters may help predict duration of ventilation and need for tracheostomy. If, at day 12, the PF ratio is less than 1, it is highly unlikely that patients will be weaned within 3 weeks, and tracheostomy should be performed. If the ratio is greater than 1, tracheostomy should be deferred, because a substantial proportion of these patients may be successfully weaned from the ventilator within 3 weeks.     

A test of the role of two prefrontal/ subcortical networks in the ��sequencing�� of non-motor, visuo-spatial information

There are a number of prefrontal/sub-cortical networks in the brain (e.g., cerebellar-thalamic-prefrontal or basal ganglia/supplementary motor cortex circuits) that despite having a clear role in motor function have been shown to be involved in non-motor tasks. In this project we test for the involvement of these networks in a dimensional judgment task that utilizes visual perceptual, visual spatial processing and requires the ordering of dimensional (height) information. Unlike previous studies examining non-motor sequencing, we directly compare both non-motor and motor versions of our dimensional judgment task. In addition, we examine activation uniquely associated with correct task responses. The findings provide evidence for the role of cortical not subcortical structures in the sequencing of visuo-spatial material apart from any motor output requirements. Our results suggest that the inferior parietal cortex (BA 7, 40) and medial frontal regions (BA 6, 8, 9 including the SMA) are instrumental to the task. Based on these results, we propose a prefrontal/parietal network plays a role in the implementation of a comparator mechanism that makes accurate comparisons along the dimension of interest, holds the information in working memory, and then (regardless of whether the information is correct or incorrect) generates a tag or abstract code that assigns the information a place in an ordered sequence. Most important, the information involved can be visual/symbolic and non-motor (not just motor) in nature.     

Dynamic testing in schizophrenia: does training change the construct validity of a test?

Dynamic testing typically involves specific interventions for a test to assess the extent to which test performance can be modified, beyond level of baseline (static) performance. This study used a dynamic version of the Wisconsin Card Sorting Test (WCST) that is based on cognitive remediation techniques within a test-training-test procedure. From results of previous studies with schizophrenia patients, we concluded that the dynamic and static versions of the WCST should have different construct validity. This hypothesis was tested by examining the patterns of correlations with measures of executive functioning, secondary verbal memory, and verbal intelligence. Results demonstrated a specific construct validity of WCST dynamic (i.e., posttest) scores as an index of problem solving (Tower of Hanoi) and secondary verbal memory and learning (Auditory Verbal Learning Test), whereas the impact of general verbal capacity and selective attention (Verbal IQ, Stroop Test) was reduced. It is concluded that the construct validity of the test changes with dynamic administration and that this difference helps to explain why the dynamic version of the WCST predicts functional outcome better than the static version.     

Validation of a home environment test battery for supporting assessments in advanced Parkinson’s disease

Test sequences in a test battery for Parkinson's disease patients, consisting of self-assessments and motor tests, were carried out repeatedly in a telemedicine setting, during week-long test periods and results were summarized in an 'overall score'. 35 patients in stable and fluctuating conditions (15 age- and gender-matched pairs) used the test battery for 1 week, and were then assessed with UPDRS and PDQ-39. This procedure was repeated 1 week later, without treatment changes. Reliability was assessed by intraclass correlation coefficients and Cronbach's alpha. Convergent validity was assessed by Spearman rank correlations and known-groups' validity, by the Mann-Whitney test. According to anonymous usability questionnaires, the patients could easily complete the tasks. Median compliance (93%) and test-retest reliability (0.88) were good. The correlations between overall score and total UPDRS (-0.64) and PDQ-39 (-0.72) were adequate. Median overall score was 18% better in the stable compared to the fluctuating group (p = 0.0014).     

Effect of antidepressant treatment on water load test and cortlsol changes in patients with functional dyspepsia

BACKGROUND: It has been demonstrated that patients with functional dyspepsia have experiences social life stress events, and accompanied by psychological disorders, mainly manifested as depression and anxiety. Mental factors can lead to excessive gastrointestinal consensual reaction, and result in different brain-gut axis disturbance, and then cause the gastrointestinal sensorimotor abnormality and endocrine changes. OBJECTIVE: To observe the effect of antidepressant treatment on the changes of water load and serum cortisol in patients with functional dyspepsia, and analyze the therapeutic mechanism. DESIGN: A comparative observation. SETTING: The First Affiliated Hospital o Zhengzhou University. PARTICIPANTS: Forty-five patients with functional dyspepsia accompanied by depression were selected from the Department of Gastroenterology, the First Affiliated Hospital of Zhengzhou University from July 2004 to July 2006, and they were 25–65 years of age, and their disease courses ranged 1–10 years. They were all accorded with the diagnostic standards for RomeⅡfunctional dyspepsia functional dyspepsia. As the patients' will, they were divided into treatment group (n =30, 12 males and 18 females) and control group (n =15, 6 males and 9 females), and there were no significant differences in the data between the two groups (P > 0.05). The programs were discussed and agreed by the committee of medical ethics of the First Affiliated Hospital of Zhengzhou University. Informed contents were obtained from all the patients. METHODS: In the treatment group, the patients were treated with venlafaxine sustained release capsule (75 mg per day), and those with sleep disorder were added by benzodiazepines (alprazolam). In the control group, the patients were given routine treatments of antacid, prokinetics, etc. Before and after 8-week treatment, the following examinations were performed: ① The gastrointestinal symptoms were assessed according to the symptoms; ② The severity of depression was evaluated with Hamilton depression scale (HAMD); ③The relaxation of proximal stomach was observed using water load test; ④ The serum level of cortisol was detected. MAIN OUTCOME MEASURES: ① Symptom score; ② HAMD score; ③ Water load amount; ④ Serum level of cortisol. RESULTS: All the 45 patients were involved in the analysis of results. ① Symptom score: The scores of gastrointestinal symptoms were decreased as compared with those before treatment in both the treatment group and control group (P < 0.05). ② HAMD scores: The scores of HAMD were decreased as compared with those before treatment in both the treatment group and control group (P < 0.05). ③ Water load amount: The total effective rate was significantly higher in the treatment group than the control group (P < 0.05). ④ The serum levels of cortisol after treatment were significantly lower than those before treatment in the patients with severe gastrointestinal symptoms in the treatment group and control group (P < 0.05). CONCLUSION: Antidepressants can normalize the cortisol level of patients with functional dyspepsia, and then decrease gastric sensitivity and ameliorates the receptive relaxation of proximal stomach, also increase the water load amount correspondingly, and finally control the gastrointestinal symptoms of functional dyspepsia.