Symbol Substitution Test (symbol + substitution_test)

Distribution by Scientific Domains

Kinds of Symbol Substitution Test

  • digit symbol substitution test


  • Selected Abstracts


    Daytime pharmacodynamic and pharmacokinetic evaluation of low-dose sublingual transmucosal zolpidem hemitartrate

    HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 1 2008
    Thomas Roth
    Abstract Objectives Buffered low-dose sublingual transmucosal zolpidem lozenge hemitartrate (ST zolpidem) is being developed for the treatment of middle-of-the-night insomnia. The objective of this double-blind placebo-controlled cross-over study (n,=,24) was to evaluate the pharmacokinetics (PK) and daytime-sedative profile of 1.0, 1.75, and 3.5,mg dose of the formulation. Methods Daytime sedation was measured pre-dose and up to 5,h post-dose objectively by the Digit Symbol Substitution Test (DSST) and subjectively using the Visual Analog Scale (VAS). Blood samples for PK assessment was collected pre-dose and up to 12,h post-dose. Results The 1.75 and 3.5,mg, but not the 1,mg, ST zolpidem produced significant sedation versus placebo within 20,min of dosing which lasted for up to 3,h. Zolpidem from the formulation was rapidly absorbed and reached maximum plasma concentrations within 38,min of dosing, however the half-life was independent of the dose and side effects were consistent with the known pharmacology of the drug. Conclusions ST zolpidem produced rapid, short duration of sedation and the effect was consistent with its PK profile. This novel low-dose formulation of zolpidem may provide clinicians and patients with a prn option for the management of sleep maintenance insomnia. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    Homocysteine, white matter hyperintensities, and cognition in healthy elderly people

    ANNALS OF NEUROLOGY, Issue 2 2003
    Carole Dufouil PhD
    Hyperhomocysteinemia is associated with an increased risk of vascular disease, and recent results suggest that it also could increase the risk of dementia. We examined the relationship between homocysteine and cognitive decline in 1,241 subjects aged 61 to 73 years, followed up over 4 years. Plasma homocysteine levels were determined in all participants as well as cardiovascular risk factors, apolipoprotein E genotype, plasma levels of folate, and vitamin B12. Cognitive performances were assessed repeatedly by using Mini-Mental State Examination, Trail Making Test, Digit Symbol Substitution Test, and Finger Tapping Test. At 2-year follow-up, 841 subjects underwent cerebral magnetic resonance imaging, and white matter hyperintensities were rated visually. Analyses were adjusted for all cardiovascular risk factors. Cross-sectional analyses showed that higher concentrations of homocysteine were significantly related to poorer performances at all neuropsychological tests. Longitudinal analyses confirmed this finding. The odds of cognitive decline was 2.8-fold (p < 0.05) higher in subjects with homocysteine levels above 15,mol/L compared with those with homocysteine levels below 10,mol/L. In participants who underwent magnetic resonance imaging, the relationship between homocysteine and cognition was unchanged after taking into account white matter hyperintensities suggesting that white matter hyperintensities do not mediate the association between homocysteine and cognition. Ann Neurol 2003;53:000,000 [source]


    Hypertension, white matter change and response to cholinesterase inhibitors in Alzheimer's disease

    INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 7 2005
    Peter J. Connelly
    Abstract Background Cholinesterase inhibitors are used to treat mild to moderate Alzheimer's disease. Their role in patients with concurrent cerebrovascular disease has been less well studied, and the influence of vascular risk factors on response to treatment is uncertain. We investigated the effect of hypertension and white matter lesions (WML) on response. Methods A retrospective sample of 160 consecutive out-patients who had blood pressure measured and the presence or absence of WML recorded at baseline and who completed six months treatment with a cholinesterase inhibitor was studied. Subjects scored either zero or one on the Modified Hachinski Ischaemic Scale. Subjects were assessed using the Mini-Mental State Examination (MMSE), the Digit Symbol Substitution test (DSST) and both the Instrumental Activities of Daily Living (IADL) and Social Behaviour (SB) sub-scales of the Nurses Observation Scale for Geriatric Patients (NOSGER). Results 43.9% of the total study population were classified as good responders using our criteria. Neither the presence of hypertension nor the presence of WML alone influenced outcome. However, there was a statistically significant interaction between blood pressure and WML on outcome variables on multiple analysis of variance (MANOVA) (F(4,,139),=,5.60, p,<,0.0005). Subjects with both hypertension and WML deteriorate to a significantly greater extent in IADL and SB scores than any other group (p,<,0.05 in each case). This effect could not be explained by age or by smoking status. Conclusion Our results support the hypothesis that there is an interaction between hypertension and WML that adversely influences functional change during cholinesterase inhibitor treatment. Our results are a contrast to suggestions that subjects with vascular disease show a better response to cholinesterase inhibitors. We recommend careful exploration of factors that may influence outcome. Copyright © 2005 John Wiley & Sons, Ltd. [source]


    Zolpidem and triazolam interact differentially with a delay interval on a digit-enter-and-recall task

    HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 2 2001
    Craig R. Rush
    Abstract Zolpidem (AMBIEN®), an imidazopyridine, is now the most commonly prescribed hypnotic in the United States. Zolpidem is neuropharmacologically distinct from benzodiazepine hypnotics in that it binds with low affinity to ,5 -containing GABAA -receptor subtypes. Despite its unique benzodiazepine-receptor binding profile, the results of most of the published studies conducted with humans suggest that the absolute magnitude of impairment produced by zolpidem is comparable to that observed with benzodiazepine hypnotics like triazolam. The present study compared the acute effects of zolpidem (0, 7.5, 15 and 22.5,mg) and triazolam (0, 0.1875, 0.375 and 0.5625,mg) in 10 non-drug-abusing humans using a Digit-Enter-and-Recall task with varying delay intervals (0, 10 and 20,s). To more fully characterize the behavioral effects of zolpidem and triazolam, several other performance tasks and subject-rated drug-effect questionnaires were included. Zolpidem and triazolam impaired performance on the Digit-Enter-and-Recall task as a function of dose under all delay intervals. However, the dose-related effects of the drugs interacted differentially with the delay interval such that zolpidem produced significantly less impairment than triazolam following the longest delay (i.e., 20,s). Zolpidem and triazolam produced comparable dose-related impairment on the digit symbol substitution test (DSST), circular lights task, and picture recall/recognition task. Zolpidem and triazolam generally produced qualitatively and quantitatively similar subject-rated drug effects, although some between-drug differences were observed. Consistent with the pharmacokinetics of these drugs, the effects of zolpidem peaked sooner and were shorter in duration than those observed with triazolam. The results of this experiment suggest that zolpidem may have less potential than triazolam to impair recall, which may be due to differences between these compounds in terms of their benzodiazepine-receptor binding profile. The results of the present study are also concordant with previous studies that found that drugs that act at the GABAA -receptor complex can be differentiated based on their interaction with the delay interval on a Digit-Enter-and-Recall task. Copyright © 2001 John Wiley & Sons, Ltd. [source]


    Modafinil reduces patient-reported tiredness after sedation/analgesia but does not improve patient psychomotor skills

    ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2010
    E. GALVIN
    Background: Early recovery of patients following sedation/analgesia and anesthesia is important in ambulatory practice. The aim of this study was to assess whether modafinil, used for the treatment of narcolepsy, improves recovery following sedation/analgesia. Methods: Patients scheduled for extracorporeal shock wave lithotripsy were randomly assigned to one of four groups. Two groups received a combination of fentanyl/midazolam with either modafinil or placebo. The remaining groups received remifentanil/propofol with either modafinil or placebo. Modafinil 200 mg was administered to the treatment group patients 1 h before sedation/analgesia. Groups were compared using the digital symbol substitution test (DSST), trail making test (TMT), observer scale of sedation and analgesia (OAA/S) and Aldrete score. Verbal rating scale (VRS) scores for secondary outcome variables e.g. energy, tiredness and dizziness were also recorded before and after treatment. Results: Sixty-seven patients successfully completed the study. Groups received similar doses of sedation and analgesic drugs. No statistically significant difference was found for DSST between groups. No significant adverse effects occurred in relation to modafinil. No statistically significant difference between groups was identified for TMT, OAA/S and Aldrete scores. The mean VRS score for tiredness was lesser in the modafinil/fentanyl/midazolam group [1.3 (2.0)] compared with the placebo group [3.8 (2.5)], P=0.02. Such a difference was not found between the remifentanil/propofol groups [placebo 2.6 (2.2) vs. modafinil 3.1(2.7)], p>0.05. Dizziness was greater in the modafinil/remifentanil/propofol group 1.7 (2.0) vs. placebo 0.0 (0.5), p<0.05. Conclusion: Modafinil reduces patient-reported tiredness after sedation/analgesia but does not improve recovery in terms of objective measures of patient psychomotor skills. [source]