Search

There is a growing body of evidence from randomized controlled trials which indicates that consumption of berries has a positive effect upon the cognitive function of healthy adults. It has been recommended that studies combining cognitive and physiological measures be undertaken in order to strengthen the evidence base for the putative effects of flavonoid consumption on cognitive outcomes. This pilot study utilized a randomized, double-blind and placebo controlled crossover design to assess the influence of the acute administration of anthocyanin-rich blackcurrant juice, standardized at 500 mg of polyphenols, on mood and attention. Additionally, this trial used electroencephalography (EEG) to assess if any changes in cognitive performance are associated with changes in localized prefrontal cortex neuronal activity in nine healthy young adults. Outcomes from the pilot EEG data highlight an anxiolytic effect of the consumption of a single serve blackcurrant juice, as indexed by a suppression of α spectral power, and an increase in the slow wave δ and θ spectral powers. There was also an indication of greater alertness and lower fatigue, as indexed by an increase in β power and suppression of α spectral power. Outcomes from the CogTrack™ system indicated a small acute increase in reaction times during the digit vigilance task. [ABSTRACT FROM AUTHOR]

Aging and depression have been found to be associated with poorer performance in mnemonic discrimination. In the current study, a two-response format mnemonic similarity test, Cognitive Drug Research MST, was used to compare these effects. Seventy-six participants were tested; with 52 participants in the young group, aged 18-35 years, and 24 participants in the elderly group, aged 55 years or older. Twenty-two young participants and 10 elderly participants met DSM-IV criteria for MDD or dysthymia. Age-related deficits were found for lure identification and speed of response. Differences in speed of responses to lure images were found for younger depressed participants, and depressive symptom severity was found to be negatively associated with lure identification accuracy in the elderly. These findings may be viewed as putative behavioral correlates of decreased pattern separation ability, which may be indicative of altered hippocampal neurogenesis in aging and depression. [ABSTRACT FROM AUTHOR]

Objective: Several potentially modifiable risk factors for cognitive decline and dementia have been identified, including low educational attainment, smoking, diabetes, physical inactivity, hypertension, midlife obesity, depression, and perceived social isolation. Managing these risk factors in late midlife and older age may help reduce the risk of dementia; however, it is unclear whether these factors also relate to cognitive performance in older individuals without dementia.Method: Data from 14 201 non-demented individuals aged >50 years who enrolled in the online PROTECT study were used to examine the relationship between cognitive function and known modifiable risk factors for dementia. Multivariate regression analyses were conducted on 4 cognitive outcomes assessing verbal and spatial working memory, visual episodic memory, and verbal reasoning.Results: Increasing age was associated with reduced performance across all tasks. Higher educational achievement, the presence of a close confiding relationship, and moderate alcohol intake were associated with benefits across all 4 cognitive tasks, and exercise was associated with better performance on verbal reasoning and verbal working memory tasks. A diagnosis of depression was negatively associated with performance on visual episodic memory and working memory tasks, whereas being underweight negatively affected performance on all tasks apart from verbal working memory. A history of stroke was negatively associated with verbal reasoning and working memory performance.Conclusion: Known modifiable risk factors for dementia are associated with cognitive performance in non-demented individuals in late midlife and older age. This provides further support for public health interventions that seek to manage these risk factors across the lifespan. [ABSTRACT FROM AUTHOR]

Background and purpose Studies investigating the association between 25-hydroxyvitamin D [25( OH) D] and cognition in the very old (85+) are lacking. Methods Cross-sectional (baseline) and prospective data (up to 3 years follow-up) from 775 participants in the Newcastle 85+ Study were analysed for global (measured by the Standardized Mini- Mental State Examination) and attention-specific (measured by the attention battery of the Cognitive Drug Research test) cognitive performance in relation to season-specific 25( OH) D quartiles. Results Those in the lowest and highest season-specific 25( OH) D quartiles had an increased risk of impaired prevalent (1.66, 95% confidence interval 1.06-2.60, P = 0.03; 1.62, 95% confidence interval 1.02-2.59, P = 0.04, respectively) but not incident global cognitive functioning or decline in functioning compared with those in the middle quartiles adjusted for sociodemographic, health and lifestyle confounders. Random effects models showed that participants belonging to the lowest and highest 25( OH) D quartiles, compared with those in the middle quartiles, had overall slower (log-transformed) attention reaction times for Choice Reaction Time (lowest, β = 0.023, P = 0.01; highest, β = 0.021, P = 0.02), Digit Vigilance Task (lowest, β = 0.009, P = 0.05; highest, β = 0.01, P = 0.02) and Power of Attention (lowest, β = 0.017, P = 0.02; highest, β = 0.022, P = 0.002) and greater Reaction Time Variability (lowest, β = 0.021, P = 0.02; highest, β = 0.02, P = 0.03). The increased risk of worse global cognition and attention amongst those in the highest quartile was not observed in non-users of vitamin D supplements/medication. Conclusion Low and high season-specific 25( OH) D quartiles were associated with prevalent cognitive impairment and poorer overall performance in attention-specific tasks over 3 years in the very old, but not with global cognitive decline or incident impairment. [ABSTRACT FROM AUTHOR]

Wesnes K, Edgar C, Andreasen N, Annas P, Basun H, Lannfelt L, Zetterberg H, Blennow K, Minthon L. Computerized cognition assessment during acetylcholinesterase inhibitor treatment in Alzheimer’s disease. Acta Neurol Scand: 2010: 122: 270–277. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objectives – Alzheimer’s disease assessment scale-cognitive subscale (ADAS-Cog) has become a standard clinical trials outcome for cognition, but has been recognized as deficient in areas including coverage of cognitive domains, sensitivity and standardization. Computerized test batteries may address some of these issues. The cognitive drug research computerized assessment (CDR) system is validated in Alzheimer’s disease (AD). This study was designed to further evaluate validity in relation to ADAS-Cog, mini mental state examination (MMSE) and cerebrospinal fluid (CSF) biomarkers and psychometric properties, in a population of Alzheimer’s patients on stable anticholinesterase treatment. Materials and methods – Patients completed cognition assessments, CSF and blood sampling at baseline and 6 months later. Data for 65 patients were evaluated. Results – The CDR system demonstrated good psychometric properties in this population. Measures of psychomotor speed showed possible sensitivity to decline over 6 months. Conclusions – There are a number of methodological problems with current cognition assessment methodology for clinical trials. Computerized measures and in particular millisecond reaction time measures, may address many of these issues. [ABSTRACT FROM AUTHOR]

The nicotinic acetylcholine receptor (nAChR) system plays a regulatory role in a number of cognitive processes. Cholinesterase inhibitors (i.e., galantamine) that potentiate cholinergic neurotransmission improve cognitive function in Alzheimer’s disease (AD); however, the relationship between these effects and associated changes in nAChRs are yet to be established in vivo. 2-[18F]Fluoro-A-85380 (2-FA) binds to nAChRs and with positron emission tomography (PET) imaging provides a composite measure of receptor density and ligand affinity. This study aimed to: (1) quantify nAChRs in vivo in 15 drug-naïve patients with mild AD before and after chronic treatment with galantamine, using 2-FA and PET, and (2) examine the relationship between treatment-induced changes in nAChRs and improvements in cognitive function. Participants were nonsmokers and underwent extensive cognitive testing and a PET scan after injection of ∼200 MBq of 2-FA on two occasions (before and after 12 weeks, galantamine treatment). A 3-day washout period preceded the second scan. Brain regional 2-FA binding was assessed through a simplified estimation of distribution volume (DVS). Performance on global measures of cognition significantly improved following galantamine treatment ( p < 0.05). This improvement extended to specific cognitive measures of language and verbal learning. No significant differences in nAChR DVS before and after galantamine treatment were found. The treatment-induced improvement in cognition was not correlated with regional or global nAChR DVS, suggesting that changes in nAChRs may not be responsible for the improvements in cognition following galantamine in patients with mild AD. [ABSTRACT FROM AUTHOR]

Cardiac surgical procedures assisted by cardiopulmonary bypass (CPB) impair cognitive functions. Several studies, however, showed that cognitive functions were unaffected in patients undergoing either primary coronary artery bypass grafting (CABG) or more complex surgery assisted by CPB. Therefore, we conducted a straightforward study to compare patient groups who differed significantly in terms of risk factors such as prolonged CPB times. Consecutive patients (n = 54) were included, undergoing either non-primary CABG, e.g. valve and/or CABG, (n = 30) or primary CABG (n = 24), assisted by CPB. Cognitive function was determined pre-operatively on the day of hospital admission, and post-operatively after one and six months using the Cognitive Drug Research computerized assessment battery. Data from the fourteen individual task variables were summarized in four composite scores: Power of Attention (PoA), Continuity of Attention (CoA), Quality of Episodic Memory (QoEM), and Speed of Memory (SoM). In the non-primary CABG patients, both CoA and QoEM improved after 1 month (p = 0.001 and p = 0.016, respectively), whereas, after 6 months, CoA (p = 0.002), QoEM (p = 0.002) and SoM (p < 0.001) were improved. In primary CABG patients, CoA improved at one month after surgery (p = 0.002) and, after six months, not only CoA (p = 0.003), but also QoEM and SoM were improved (p = 0.001 and p = 0.030, respectively). The test performance was similar in non-primary and primary CABG patients after surgery. Our present study shows a post-operative improvement of cognitive composite scores after cardiac surgery assisted by CPB in both non-primary CABG and in primary CABG patients. [ABSTRACT FROM AUTHOR]

The study examines the effects of the antioxidant flavonoid Pycnogenol on a range of cognitive and biochemical measures in healthy elderly individuals. The study used a double-blind, placebo-controlled, matched-pair design, with 101 elderly participants (60-85 years) consuming a daily dose of 150 mg of Pycnogenol for a three-month treatment period. Participants were assessed at baseline, then at 1, 2, and 3 months of the treatment. The control (placebo) and Pycnogenol groups were matched by age, sex, body mass index, micronutrient intake, and intelligence. The cognitive tasks comprised measures of attention, working memory, episodic memory, and psychomotor performance. The biological measures comprised levels of clinical hepatic enzymes, serum lipid profile, human growth hormone, and lipid peroxidation products. Statistically significant interactions were found for memory-based cognitive variables and lipid peroxidation products, with the Pycnogenol group displaying improved working memory and decreased concentrations of F2-isoprostanes relative to the control group. [ABSTRACT FROM AUTHOR]

OBJECTIVE:: To compare executive, memory and visuospatial functioning of DSM-IV anorexia nervosa (AN), bulimia nervosa (BN), and normal controls (NC). METHOD:: A comparison of women involving: (i) 16 AN with body mass indices (BMI) 18.5 kg/m(2) for at least 3 months; (iii) 13 BN; and (iv) 16 NC participants was performed with groups of similar age and intelligence. Groups were assessed with EDE-12, MADRS, HAMA, Cognitive Drug Research (CDR) battery, and Bechara tasks. RESULTS:: Significant impairments in CDR Power of Attention were present in underweight AN and BN participants. CDR Morse Tapping was significantly impaired in all clinical groups. The BN and weight-recovered AN groups were significantly impaired on CDR immediate word recall. The BN group alone was significantly impaired on CDR delayed word recall. CONCLUSION:: Attentional impairment is similar in AN and BN. Impaired motor tasks in AN persist after 'weight-recovery' and are similar to impairments in BN. BN may be discriminated from AN on word recall. (c) 2007 by Wiley Periodicals, Inc. Int J Eat Disord 2007. [ABSTRACT FROM AUTHOR]

Background Atypical antipsychotics may be beneficial in treating the core psychopathology of anorexia nervosa (AN). Methods An 8 week open-label study of quetiapine was conducted in eight severely ill DSM-IV AN patients consecutively admitted to a specialist eating disorders unit. Participants were assessed by EDE-12, MADRS, YBOCS, SAPS-delusions and CDR neuropsychological battery at baseline, 4 weeks and 8 weeks, and by weekly body mass index (BMI), CGI and extrapyramidal scores. Quetiapine doses ranged from 50 mg to 800 mg per day, according to efficacy and tolerability. Results Seven participants completed 4 weeks and five participants completed 8 weeks. All participants had clinically significant levels of specific eating disorders psychopathology, and mild to moderately severe depressive symptomatology. Apart from initial mild sedation, no subjects experienced any significant adverse events. Over 4 weeks there was no significant difference in BMI, but a significant difference in the EDE-12 restraint score. There were significant differences on BMI and EDE-12 restraint subscale scores over 8 weeks. Conclusions A double-blind placebo controlled study is required to further evaluate the therapeutic utility of quetiapine in severely ill AN patients beyond multidisciplinary specialist intervention. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The aim of this study was to get insight into the central effects of TC-1734 (renamed AZD3480), a selective agonist at the neuronal nicotinic receptor of the α4β2 subtype. Electroencephalography (EEG) techniques and computerized cognitive tests were performed in young, healthy male volunteers during two double-blind and placebo-controlled studies: a rising single dose crossover study (from 2 to 320 mg) and a rising repeated dose study with a parallel group design (50, 100, and 200 mg). In contrast to acute administration, administration of AZD3480 over 10 days produced statistically significant enhancement of several cognitive measures (attention and episodic memory) compared to placebo. Regarding EEG data, AZD3480 showed acceleration of the alpha centroid and of the alpha peak in the single-dose study. This EEG profile of the acceleration type was confirmed in the repeated dose study on both day 1 and day 10, with the greatest effect observed with the highest dose. The EEG pattern shown for AZD3480 was consistent with that previously described with other drugs known to improve attention and vigilance (including nicotine). In addition, subjects dosed with AZD3480 showed a statistically significant increase in mismatch negativity (MMN) amplitude at 50 and 200 mg while reducing MMN latency (200 mg only), suggesting an improvement of pre-attentional mechanisms. These early data in healthy subjects provide encouragement to consider development of AZD3480 as a novel agent for the treatment of cognitive decline in the elderly, including age-associated memory impairment and/or dementia of the Alzheimer’s type. [ABSTRACT FROM AUTHOR]

Background: We examined attention-enhancing effects of the cholinesterase inhibitor donepezil in Dementia with Lewy bodies (DLB) and Parkinson's disease with dementia (PDD) by means of open label study. Methods: 22 DLBs and 23 PDDs were assessed over 20 weeks using the Cognitive Drug Research Computerized Attentional Tasks. We examined how much closer our patients moved towards being normal for their age by comparing them to a non-demented elderly control sample (n = 183, aged 71-75 years). Results: Donepezil treatment improved power of attention, continuity of attention and reaction time variability. The deficit in responses was moved towards normal by 38 and 56% for power of attention and 22 and 10% for continuity of attention in PDD and DLB, respectively. Conclusions: Improvements in attention were found with donepezil in PDD and DLB. Copyright (c) 2007 S. Karger AG, Basel. [ABSTRACT FROM AUTHOR]

The present study aimed to systematically assess acute, dose-related behavioural effects of an extract of guaraná plant for the first time in humans. This double-blind, counterbalanced, placebo-controlled study (n = 26) assessed the acute mood and cognitive effects throughout the day of four different doses (37.5mg, 75mg, 150mg and 300mg) of a standardised guaraná extract (PC-102). Assessment included the Cognitive Drug Research computerized test battery and Bond-Lader mood scales. Guaraná improved secondary memory performance and increased alert and content mood ratings. The two lower doses produced more positive cognitive effects than the higher doses. This research supports previous findings of cognitive improvements following 75 mg guaraná and provides the first exploration of different dose effects of guaraná in humans. The findings suggest that the effects cannot be attributed to caffeine alone. [ABSTRACT FROM AUTHOR]

Background: Levodopa (L-dopa) is the gold standard treatment for Parkinson's disease, but a lack of clear efficacy combined with a perceived liability to neuropsychiatric side effects has limited L-dopa use in patients with parkinsonism and dementia. Therefore, the effect of L-dopa on the cognitive profile of dementia with Lewy bodies (DLB) and Parkinson's disease with dementia (PDD) is unclear. Aim: To ascertain the acute and long-term effects of L-dopa on aspects of attention and cognition in patients with DLB and PDD, and to compare these with the effects in Parkinson's disease. Method: Baseline cognitive and motor function was assessed off L-dopa in patients with Parkinson's disease (n = 22), PDD (n = 27) and DLB (n = 11) using standard ‘bedside’ measures and a computerised programme detecting reaction times and accuracy. All patients then underwent an acute L-dopa challenge with subsequent subjective and objective analysis of alertness, verbal recall, reaction times and accuracy. The same parameters were measured after 3 months on L-dopa to assess the prolonged effect. Results: Acute L-dopa challenge considerably improved motor function and subjective alertness in all patients without compromising either reaction times or accuracy, but increased fluctuations were noted in both groups with dementia. Neuropsychiatric scores improved in patients with Parkinson's disease both with and without dementia on L-dopa at 3 months. Although patients with Parkinson's disease also had better mean global cognitive function at this time, mean verbal attention and memory deteriorated, and patients with PDD had slower reaction times in some tests. No patient had a marked deterioration over this time. Patients with DLB did not experience any adverse cognitive or neuropsychiatric effects after 3 months of L-dopa treatment. Conclusion: The use of L-dopa in patients with parkinsonism with dementia does not adversely affect cognitive function. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of attentional deficits on activities of daily living (ADL) in patients with dementia associated with Parkinson's disease (PDD). Method: 461 patients were assessed neuropsychologically. Factor analyses were used to differentiate attention from other cognitive functions and to differentiate different aspects of ADL functions. The effects of the attentional measure on ADL were examined using sequential multiple regression, controlling for age, sex, education, severity of motor symptoms and other cognitive functions. Results: Three cognitive factors were identified, with one factor emerging as a measure of vigilance and focused attention. This factor predicted different aspects of ADL status even after controlling for motor functions and other cognitive factors. The attention factor was the single strongest cognitive predictor of ADL status, matching the strength of the effects of motor functions on ADL status. Conclusion: Impaired attention is an important determinant of ADL functions in patients with PDD. [ABSTRACT FROM AUTHOR]

Melissa officinalis (Lemon balm) is a herbal medicine that has traditionally been attributed with memory-enhancing properties, but which is currently more widely used as a mild sedative and sleep aid. In a previous study it was demonstrated that a commercial Melissa extract led to dose-specific increases in calmness, and dose-dependent decrements in timed memory task performance. However, the extract utilized in that study did not exhibit in vitro cholinergic receptor-binding properties. The current study involved an initial screening of samples of M. officinalis for human acetylcholinesterase inhibition and cholinergic receptor-binding properties. The cognitive and mood effects of single doses of the most cholinergically active dried leaf were then assessed in a randomized, placebo-controlled, double-blind, balanced crossover study. Following the in vitro analysis, 20 healthy, young participants received single doses of 600, 1000, and 1600 mg of encapsulated dried leaf, or a matching placebo, at 7-day intervals. Cognitive performance and mood were assessed predose and at 1, 3, and 6 h postdose using the Cognitive Drug Research computerized assessment battery and Bond-Lader visual analog scales, respectively. In vitro analysis of the chosen extract established IC50 concentrations of 0.18 and 3.47 mg ml-1, respectively, for the displacement of [³H]-(N)-nicotine and [³H]-(N)-scopolamine from nicotinic and muscarinic receptors in human cerebral cortex tissue. However, no cholinesterase inhibitory properties were detected. The most notable cognitive and mood effects were improved memory performance and increased 'calmness' at all postdose time points for the highest (1600 mg) dose. However, while the profile of results was overwhelmingly favorable for the highest dose, decrements in the speed of timed memory task performance and on a rapid visual information-processing task increased with decreasing dose. These results suggest that doses of Melissa officinalis at or above the maximum employed here can improve cognitive performance and mood and may therefore be a valuable adjunct in the treatment of Alzheimer's disease. The results also suggest that different preparations derived from the same plant species may exhibit different properties depending on the process used for the sample preparation. [ABSTRACT FROM AUTHOR]

We compared a computerized version of the Cognitive Drug Research (CDR) cognitive assessment test battery and a completely automated telephone version of the same battery. These assessed aspects of attention, working memory and long-term memory. Both methods were used to assess the cognitive performance of a cohort of 30 people with confirmed chronic fatigue syndrome (CFS) and a group of 30 healthy controls matched for age and education. The CFS group had significantly slower reaction times on all four cognitive measures on both the computerized and telephone tests. The mood data followed similar patterns in the computer and telephone assessments. The results from both forms of the test battery confirmed the pattern and severity of cognitive impairment in CFS. Furthermore, the two methods of testing were similarly sensitive in detecting cognitive deficits. The incapacitating nature of CFS may cause problems for researchers if the restrictions to mobility affect the representativeness of the study group. The findings of the present study support the use of a fully automated telephone cognitive testing system for detecting deficits in CFS. [ABSTRACT FROM AUTHOR]

Summary Flumazenil is traditionally administered intravenously to reverse the adverse effects of over sedation with benzodiazepines. The aim of this study was to test postoperative cognitive and psychomotor recovery from midazolam conscious sedation, following reversal with orally administered flumazenil. It was hypothesised that when administered by the oral route, flumazenil may enhance recovery over a prolonged period, thus increasing safety. Eighteen patients requiring intravenous midazolam sedation for dental treatment completed a randomised, double-blind, crossover trial. Following treatment the patients' sedation was reversed using either flumazenil or saline (asplacebo), administered orally, on alternate appointments. Assessment of mood and cognitive function were undertaken using ClinPhone.cdr®, a highly sensitive and specific computerised battery of cognitive tests administered by telephone prior to sedation and every hour for seven hours post reversal. Results indicate that within 20 min of administration, oral flumazenil is capable of partially reversing some cognitive and psychomotor impairments but the attentional and stimulus discrimination effects of midazolam sedation still remain. [ABSTRACT FROM AUTHOR]

Objectives: To assess the possible effects of flumazenil on cognitive processing, physiology, and mood. Design A double-blind, placebo controlled, four-way cross-over study, using healthy volunteers.Methods: On each of 4 separate visits, 16 participants received 0.5 mg, 2.5 mg, 5.0 mg of flumazenil, or normal saline. They then performed a computerised test battery assessing cognitive function. Measures of pulse rate, arterial oxygen saturation and mean arterial pressure were also taken. Finally, participants completed visual analogue scales assessing their subjective mood state.Results: The majority of cognitive tasks showed dose-dependent declines in performance. Mean arterial pressure was significantly reduced, as was pulse rate. Subjective alertness showed a similar decline.Conclusions: Flumazenil has been clinically described as an agent with few intrinsic properties, whose primary effect lies in its ability to reverse benzodiazepine-induced states. This study has shown that flumazenil does possess intrinsic activity which have a significant effect on cognition, cardiovascular physiology and mood. Clinicians need to be aware of these effects. [ABSTRACT FROM AUTHOR]

Background: The identification of fluctuating confusion is central to improving the differential diagnosis of the common dementias.Aims: To determine the value of two rating scales to measure fluctuating confusion.Method: The agreement between the clinician-rated scale and the scale completed by a non-clinician was determined. Correlations between the two scales were calculated; variability in attention was calculated on a computerised cognitive assessment and variability in delta rhythm on an electroencephalogram (EEG).Results: The Clinician Assessment of Fluctuation and the computerised cognitive assessment were completed for 155 patients (61 Alzheimer's disease, 37 dementia with Lewy bodies, 22 vascular dementia, 35 elderly controls). A subgroup (n = 40) received a further evaluation using the One Day Fluctuation Assessment Scale and an EEG. The two scales correlated significantly with each other, and with the neuropsychological and electrophysiological measures of fluctuation.Conclusions: Both scales are useful instruments for the clinical assessment of fluctuation in dementia. [ABSTRACT FROM AUTHOR]

In this double-blind, placebo controlled, four-way cross-over trial in 16 healthy elderly volunteers, the acute effects of haloperidol 2 mg, amisulpride 50 mg and 200 mg, were assessed on a range of tests of cognitive function. On each study day, cognitive performance was assessed prior to dosing and at 2, 4, 6, 9, 12 and 24 h after dosing with the following tests from the Cognitive Drug Research computerized assessment system: simple reaction time, digit vigilance task, choice reaction time, visual tracking, Critical Flicker Fusion, body sway, numeric working memory, immediate and delayed word recall, word recognition and self-ratings of mood and alertness. Haloperidol showed a general tendency to impair performance, and although this did not reach significance compared to placebo, for two tasks there were significant impairments with haloperidol compared to amisulpride. Amisulpride 50 mg and 200 mg, was not associated with impairment. In fact, there was some suggestion of improvement over placebo on three measures. The timings of assessment were appropriate for the study compounds. Furthermore, in a recent study in which a smaller number of elderly volunteers was tested on the same cognitive assessment system, a clear profile of acute impairments of haloperidol 3 mg, was identified. This indicates that haloperidol 2 mg, is not a sufficient dose to affect cognitive function in the elderly, supporting the general absence of effects with this dose in the young. Thus, the general absence of cognitive impairments with amisulpride at the doses used in this study suggests that this compound does not impair cognitive function in the elderly. [ABSTRACT FROM AUTHOR]

Objectives: To compare the effects of nitrous oxide and midazolam on cognition and mood.Design: A three-way, counterbalanced, cross-over study, using patients receiving conscious sedation for routine dental treatment.Methods: On each of three separate visits, patients performed a computerised test battery to determine baseline cognitive performance. Then, following administration of either midazolam, nitrous oxide, or no drug, patients re-performed the test battery. Finally, patients completed visual analogue scales assessing their subjective mood state.Results: Relative to baseline performance, midazolam administration produced significantly slower reaction times compared with nitrous oxide and no-drug conditions. Furthermore, patients receiving midazolam were impaired in accuracy relative to the other conditions on many of the cognitive tasks, particularly those assessing the recall of information. Patient performance in nitrous oxide and control conditions did not significantly differ. These results could not be explained by differences in mood between the conditions, as subjective mood ratings during midazolam or nitrous oxide administration were very similar.Conclusions: It is important for clinicians to be aware that peri-operative recall of information is reduced in patients who have undergone midazolam sedation. This is an advantage for patients who are anxious, and do not wish to be aware of the operative treatment being performed. However, as the cognitive impairment is enduring, an adult escort and written post-operative instructions should be mandatory for midazolam sedation patients. In contrast, the use of nitrous oxide sedation does not significantly impair higher cognitive tasks and thus patients receiving nitrous oxide sedation can resume normal activities in the post-operative period. [ABSTRACT FROM AUTHOR]

Fluctuating levels of consciousness (FC) are a key feature in neurodegenerative dementias, yet clinical identification is poor, hindering accurate diagnosis. One hundred and nineteen patients (32 Dementia with Lewy Bodies (DLB), 57 Alzheimer's disease (AD) and 30 controls) with clinical scores of FC were assessed using an attentional task. Cortical arousal was assessed in 25 of these patients using electroencephalography. Over 90 s both variability in attention (p <0·0001) and fluctuations in electrocortical activity (p <0·0001) correlated with clinical FC scores, and with each other (p <0·0001). Variability in attention and electrocortical arousal are accurate FC markers and can assist differential diagnosis of AD and DLB. Previous work has underestimated the intensity and hence impact of FC in dementia. Copyright © 1999 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The primary objective of the study was to investigate the criterion validity of the Cognitive Drug Research CDR computerized system in assessing cognitive functioning among persons with brain injury or other organic illness. Understanding the cognitive effects of pharmacotherapy is important in improving long term rehabilitation outcomes in persons with organic disorders. The CDR system evaluates cognitive skills of attention, short term or working memory, long term memory, and visuomotor and motor functioning. For validity testing, correlation coefficients were obtained from an analysis of CDR scores to IQ and Folstein Mini Mental State Exam MMSE scores. Subtests of the CDR system that correlated with the MMSE were choice reaction time R = 0.542, p = 0.04 , spatial working memory R = 0.938, p = 0.01 , and word recognition R = 0.949, p = 0.01 . These tests primarily measured attention and working memory. Correlations between the CDR and IQ scores were not evident. In summary, the data suggest the CDR assessment system has high patient acceptability by persons with traumatic brain injury, and is a useful tool in assessing certain domains of cognition, specifically short term memory, discrimination, and identification skills. [ABSTRACT FROM AUTHOR]

The cognitive and psychomotor effects of olanzapine (3 mg) were compared with haloperidol (3 mg) and placebo in a double-blind, cross-over study. Fourteen healthy elderly volunteers (>65 years) were randomized to receive once daily medication for 4 days with a 16-day interval between treatment periods. Assessments of attention, memory and motor control were made prior to dosing on each day, at 2, 4, 6 and 8 h after dosing on days 1 and 4, and at 24 and 48 h following the last dose. On day 1, detectable impairment was observed at all time points in both groups. On day 4, haloperidol treated subjects showed increased impairment compared with day 1 and this was sustained throughout the 48 h of testing. Olanzapine treated subjects showed reduced day 4 deficit (compared with day 1), with no significant difference from placebo beyond 6 h post dose. These results suggest that both haloperidol and olanzapine have a measurable initial effect on cognitive and psychomotor function in elderly volunteers. However, acute effects associated with olanzapine decrease with repeated dosing and show substantial adaptation within 4 days. In contrast, effects seen with haloperidol are sustained and increase with repeated dosing over the same period. [ABSTRACT FROM AUTHOR]

Purpose : To examine whether a simulated mobile telephone transmission at 915MHz has an eff ect on cognitive function in man. Materials and methods : Thirty-six subjects in two groups were each given two training sessions and then three test sessions in a randomized three-way cross-over design. About 1W mean power at 915MHz from a quarter-wave antenna mounted on a physical copy of an analogue phone, as a sine wave, or modulated at 217Hz with 12.5% duty cycle, or no power, was applied to the left squamous temple region of the subjects while they undertook a series of cognitive function tests lasting 25-30min. The second group was investigated for sleep, consumption of alcohol and beverages, and any other substances that might aff ect performance. Results : In both groups, the only test aff ected was the choice reaction time and this showed as an increase in speed (a decrease in reaction time). There were no changes in word, number or picture recall, or in spatial memory. While an eff ect of visitorder was evident suggesting a learning eff ect of repeat tests, the design of the study allowed for this. Additionally, there was no systematic error introduced as a result of consumption of substances or sleep time. Conclusions : There was evidence of an increase in responsiveness, strongly in the analogue and less in the digital simulation, in choice reaction time. This could be associated with an eff ect on the angular gyrus that acts as an interface between the visual and speech centres and which lies directly under and on the same side as the antenna. Such an eff ect could be consistent with mild localized heating, or possibly a non-thermal response, which is nevertheless power-dependent. [ABSTRACT FROM AUTHOR]

Twenty regular smokers were assessed over 24-h of normal cigarette smoking, and an equivalent period of abstinence, in both conditions, a non-deprived baseline was followed by performance tests 2, 6 and 24 h later, while subjective feelings were assessed every 2 h. Compared to normal smoking, abstinence led to reduced heart rate, worse task performance, feelings of depression, stress, irritability, restlessness, poor concentration, and urges to smoke. Letter cancellation and number vigilance task performance were significantly poorer after 2 and 6 h of abstinence. Subjective feeling stales were significantly worse after 4 h of abstinence, and became increasingly impaired over the rest of the day. However many abstinence symptoms (except heart rate), were reduced in severity at the 24-h session, held on the morning of the following day. This suggests that many of the psychological effects of smoking abstinence, may build-up afresh each day. [ABSTRACT FROM AUTHOR]

The present study was conducted to determine the degree to which impairments in attention accompany the memory deficits produced by scopolamine. Eighteen healthy young volunteers received scopolamine 0·6 mg subcutaneously on three experimental sessions and placebo on three others, On each session, prior to, and 60mm alter injection, the subjects underwent an automated computerized battery of 11 cognitive tasks. The study was run double-blind and the order of treatment conditions over successive visits was counterbalanced between subjects. Scopolamine produced marked and significant decrements on all major aspects of performance from the battery. The drug lowered the efficiency of the detection and processing of information in tests of visual vigilance, rapid information processing. choice reaction, letter cancellation and logical reasoning. These effects were accompanied by a lowering of critical flicker-fusion frequency and subjective alertness. Memory was also impaired on tests of immediate recall, delayed recall, recognition and memory scanning. These findings confirm and extend previous work, demonstrating that scopolamine impairs the selection and evaluation of environmental information, as well as reducing the likelihood of information being subsequently recalled or recognized. Whether the former effects contribute to the latter is not known, but this must be considered a possibility. This potential role of processing deficits in memory loss associated with cholinergic blockade is briefly considered in relation to the cholinergic hypothesis of geriatric memory loss. [ABSTRACT FROM AUTHOR]

Fifty-four elderly patients, living at home, completed a 3-month, double-blind, randomized, placebo-controlled trial of the effects of Tanakan on both cognitive efficiency and the quality of life. Patients were included in the study if they showed mild signs of impairment in everyday function on the Crichton Geriatric Rating Scale. Cognitive efficiency was measured before and at monthly intervals during the trial using a battery of tests of mental ability comprising both computerized and pencil-and-paper tasks. The quality of life was assessed using a behavioral questionnaire which was administered before and after the study. Individual analyses of the cognitive tests showed some advantage of Tanakan over placebo, hut when the accuracy scores from all eight tests were combined using two different techniques. although both groups improved over time, the improvement with Tanakan at week 12 was significantly greater than with placebo. No signs of improvement were detected with placebo when the reaction time measures were combined using these techniques. whereas by week 4 the Tanakan group were significantly faster than at baseline, and were superior to placebo throughout the study. These improvements in mental efficiency were accompanied by a significant increase in the interest taken in everyday activities, and suggest that the drug might be helpful in treating the early stages of primary degenerative dementia. [ABSTRACT FROM AUTHOR]

Demented elderly patients (N = 23, aged 60–94) and controls (N = 22, aged 52–86) performed a version of the Cognitive Drug Research computerized Assessment System comprising cognitive tasks measuring choice reaction time, vigilance, and the sensitivity and speed of digit, word and picture recognition. The demented patients showed large and highly significant impairments in the speed of choice reaction and in the sensitivity and speed of all memory tasks. Correlations between the various scores from the computerized tests and those from the Folstein Mini-mental State Examination, the Kendrick Battery and the Kew were high and significant, implying the computerized tasks measure similar aspects of cognition to procedure used to assess dementia. In 16 memory clinic patients, high correlations were also found between the Stockton Rating Scale and the scores from the computerized tests, suggesting that the latter have relevance to the general behavioural condition of the patients. These findings, together with evidence of good test-retest reliability, indicate that, for demented patients, the utility of this system to assess cognitive change should be comparable to that of previous versions used with the young and with non-demented elderly. [ABSTRACT FROM AUTHOR]

Single oral doses of promethazine (12.5 mg, 25 mg), scopolamine (0.6 mg), and cinnarizine (30 mg), were compared in a double-blind, placebo controlled trial. Twelve normal volunteers undertook a battery of psychological performance tests and a feeling state questionnaire, before drug administration, and at 2-h intervals after. Promethazine and cinnarizine significantly impaired psychomotor performance, information processing and feelings of alertness. With promethazine these reductions were maximal 3-4 h post-drug, with performance returning near to baseline 8-9 h post-drug. With cinnarizine these impairments were maximal 5-6 h post-drug, and performance remained depressed 8-9 h post-drug. Scopolamine significantly reduced feelings of alertness, and memory task performance; the overall performance effects were most evident 1-4 h post-drug. [ABSTRACT FROM AUTHOR]

Previous work in this and another laboratory has shown that nicotine tablets improve the performance of a rapid information processing task and reduce the Stroop effect, whereas scopolamine has the opposite effects. The purpose of this study was to extend these previous findings by determining whether, when administered together, these two drugs have mutually antagonistic effects on task performance. Two experiments are reported, both using within-subjects double-blind Latin Square designs. In the first, six subjects received single and combined doses of scopolamine 1.2 mg and nicotine 1.5 mg, and there was some evidence that the two drugs had mutually antagonistic effects on the rapid information processing task. In the second experiment 12 subjects received the same doses, but rapid information processing testing was carried out over a longer time period and Stroop testing was introduced at the end of the 2.5 h session. Nicotine was found to counteract the depression of performance produced by scopolamine on both the rapid information task and the Stroop test. These results provide further support for the theory that central cholinergic pathways play a major role in human information processing. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the effects of four cigarettes having a range of covarying nicotine and 'tar' yields on the performance of a rapid information processing task. Twenty five smokers were tested on different days with each of the cigarettes and in a non-smoking control condition. The order of testing was counterbalanced over days using a 5×5 Latin Square Design. Not only did smoking help to prevent the decrease in speed and accuracy which occurred over time in the non-smoking conditions, but it actually improved performance over baseline levels. Furthermore, the greatest improvements were found with the higher nicotine yielding cigarttes. These objectively measured effects of the cigarettes on performance matched the subjective evaluations of the effects of the cigarettes outside the laboratory, and are discussed in relation to other questionnaire studies and a survey of smoking at work. [ABSTRACT FROM AUTHOR]