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Cognitive disturbances and regional cerebral blood flow abnormalities in migraine patients: their relationship with the clinical manifestations of the illness.

The purpose of the present study was to evaluate neuropsychological performance and regional cerebral blood flow in migraine patients, and to investigate whether possible abnormalities in any of these fields could be related to the chronicity of the disease. The sample included 60 patients and 30 healthy control subjects; all of them were subjected to a complete neuropsychological assessment, including emotional variables. In addition an interictal 99Tc-HMPAO SPECT was performed in 56 patients and 15 controls. Disturbances in memory, attention and visuomotor speed processing were observed among migraineurs experiencing higher frequency of attacks and in those with a long history of migraine. Anxiety levels were higher in patients than in controls and were positively correlated with attack frequency, but not with cognitive test scores. Brain perfusion abnormalities, mostly hypoperfusion areas, were found in the 43% of patients; poorer performance in two tests, measuring verbal and visual memory, respectively, was found in these patients.

Adolescent↗

Effectiveness of a visual attention retraining program on the driving performance of clients with stroke.

OBJECTIVE: To compare the effectiveness of a visual attention retraining program using the Useful Field of View (UFOV) with a traditional visuoperception treatment program on the driving performance of clients with stroke. DESIGN: Randomized controlled trial. SETTING: Rehabilitation hospital located in Quebec, Canada. PARTICIPANTS: Ninety-seven individuals referred for driving evaluation after a stroke. INTERVENTIONS: Participants were randomized to receive 20 sessions of either UFOV training of visual processing speed, divided attention, and selective attention or traditional computerized visuoperception retraining. MAIN OUTCOME MEASURES: Subjects were evaluated with an on-road driving evaluation, visuoperception tests, and the Test of Everyday Attention. An occupational therapist unaware of group assignment conducted all evaluations. RESULTS: Eighty-four participants completed the outcome evaluation. There were no significant differences between groups on any of the outcome measures. There was, however, almost a 2-fold increase (52.4% vs 28.6%) in the rate of success on the on-road driving evaluation after UFOV training for subjects with right-sided lesions. CONCLUSIONS: Rehabilitation that targets visual attention skills was not significantly more beneficial than traditional perceptual training in improving the outcome of an on-road driving evaluation. However, results suggest a potential improvement for subjects with right-sided lesions, indicating that training must target specific skills.

Aged↗

The effects of oestrogens and anti-oestrogens on cognition.

Recent research suggests that oestrogen may play an important role in cognition. Epidemiological and experimental studies of hormone replacement therapy in post-menopausal women suggest that oestrogen may be important to verbal memory in particular, as well as other cognitive functions such as attention and processing speed. Some studies have also suggested that HRT may have a beneficial effect for Alzheimer's disease, both in the prevention or delay of onset and that it is also of therapeutic benefit to patients in whom the disease is established. The use of selective oestrogen receptor modulators (SERMs) and other hormonal therapies for the treatment of breast cancer is common, yet few studies have examined the possible cognitive effects of this form of treatment. Several studies have shown cognitive decline in women receiving treatment for breast cancer, but the focus has been on the effects of chemotherapy. Further confusion has resulted from the diverse methodologies used in the existing literature. A pilot study to develop a suitable cognitive battery of tests for the evaluation of cognitive function in women receiving hormonal therapy for the treatment or prevention of breast cancer is introduced.

Journal Article↗

Double-blind, placebo-controlled psychometric studies on the effects of a combined estrogen-progestin regimen versus estrogen alone on performance, mood and personality of menopausal syndrome patients.

The influence of a combined estrogen-progestin regimen (Climodien) on noopsyche, thymopsyche, personality and psychophysiological measures of menopausal syndrome patients was investigated in a double-blind, placebo-controlled, comparative, randomized 3-arm trial phase (Climodien 2/3 = estradiol valerate (CAS 979-32-8) 2 mg + the progestin dienogest (CAS 65928-58-7) 3 mg = regimen A, estradiol valerate 2 mg = regimen EV, and placebo = regimen P) followed by an open-label phase in which all patients received Climodien 2/2 (estradiol valerate 2 mg + dienogest 2 mg) = regimen A*. 49 women (16, 17, 16 valid patients per arm) aged between 46 and 67 years (mean 58, 58, 56 years, respectively) with the diagnoses of insomnia (G 47.0) related to postmenopausal syndrome (N 95.1) were included in the analysis of the double-blind phase. Both the double-blind and the open-label phase lasted 2 months. Noopsychic investigations demonstrated an improvement in associative verbal memory after 2 months of regimen A, which was significant as compared with both baseline and placebo. Regarding visual memory, regimen A* induced an improvement, which was significantly different from the decline in correct reproductions in the Benton Test observed under estradiol. Errors in the Benton Test decreased significantly after regimen A* as compared with regimen EV. These findings suggest that hormone replacement therapy with estradiol, and even more in combination with dienogest, improves verbal and visual memory, which is in line with the improvement in information processing speed and capacity objectified by event-related potentials (ERP). Thymopsychic investigations demonstrated a significant improvement in somatic complaints and trait anxiety after both regimen A and regimen EV as compared with baseline. State anxiety decreased significantly under regimen A* as compared with EV. The Freiburger Personality Inventory showed an improvement in aggressivity after regimen A* as compared with the preceding placebo as well as an improvement in striving after dominancy after both regimen A and regimen EV as compared with pre-treatment, but also after regimen A* as compared with regimen EV. Extraversion increased after 2 months of regimen A as compared to regimen P. Psychophysiological findings including pupillary and skin conductance variables were not significant.

Affect↗

Outcome of medulloblastoma in children: long-term complications and quality of life.

To study the outcomes in long-term survivors of paediatric medulloblastoma (MB), we followed 51 consecutive children who were treated between 1980 and 2000 in a single institution. In 18 of 26 survivors (mean follow-up time 12.2 years), tumour control, neurological, endocrine, and neurocognitive complications and their impact on behavioural and psychological adjustment, and health-related quality of life (QoL) were comprehensively assessed using qualitative and quantitative measures. Endocrine deficits occurred in 61 %, neurological complications in 72 %, and significant school problems in 72 %. All patients had significant deficits in neurocognitive functioning: attention and processing speed was impaired in 79 %, learning and memory in 88 %, language in 56 %, visual perception in 50 %, and executive functions in 64 %. In comparison with healthy controls, social functioning was rated by the patients as the QoL dimension most affected. Parents' ratings were considerably lower than those of the patients. No MB survivor > 18 years of age (n = 12) had a boy- or girlfriend. Because of their treatment, including craniospinal radiotherapy, MB long-time survivors are not only at great risk for neurological, endocrine, and neurocognitive complications, but also of social isolation thereby decreasing self-rated QoL substantially.

Activities of Daily Living↗

[The "Lower Saxony/Northern Rhine-Westphalia" Neuroblastoma Screening Project: on the need for epidemiologic comparison].

The proof for the general evolution of metastatic neuroblastoma from localized disease by a low-speed process is lacking. The epidemiological approach would require the decrease of neuroblastoma related mortality by reduction of the number of metastatic cases per population unit as a result of a screening program. During 1983 through 1990 the neuroblastoma incidence in the FRG was 0.85-1.09 cases per 100,000 children less than 15 years of age. The mortality rate ranged between 0.25 and 0.49 deaths per 100,000 children. The project "Niedersachsen/Nordrhein-Westfalen" started April 1st, 1992 and is investigating urinary catecholamine metabolite excretion in infants at the age of 10-12 months and for a second time in toddlers at 17-19 months. The target population includes 24.7 million inhabitants with 267,000 births per year. The urine sampled on filter paper is analyzed using thin layer chromatography. Positive and questionable positive results are confirmed by HPLC and GC-MS. The aim of the study is to demonstrate the feasibility of the chosen approach. Furthermore first epidemiological data will be obtained. Until a population-based study on neuroblastoma mortality in screened versus controlled populations has proven the usefulness of the screening it cannot be recommended as a general service to the public.

Adolescent↗

[Patchy changes in white matter in cranial computerized and magnetic resonance tomography--significance for (differential) diagnosis of dementia of the Alzheimer type and vascular dementia].

With the advancement of technical progress, especially with respect to magnetic resonance imaging, patchy cerebral white matter lesions (WML) are being found with increasing frequency. The (differential) diagnosis between the two main dementias of old age, (senile) dementia of the Alzheimer type ([S]DAT) and vascular dementia (VD) is made more frequently in favour of the latter, since the detection of WML leads to support a vascular origin for dementia. The present article reviews the literature concerning X-ray computed tomography (CT) and magnetic resonance imaging (MRI) in these disorders. For comparison purposes some methodological problems must be taken into account including different scoring systems for WML severity, differences in imaging techniques and in the criteria for the selection of patients and controls. A great number of studies demonstrates a strong association of frequency and severity of WML with increasing age and presence of cerebrovascular risk factors such arterial hypertension. Some studies revealed an association with neuropsychiatric deficits including gait disorders, urinary incontinence, affective lability and reduced attention and information processing speed. In CT studies, about 30% of patients with (S)DAT had WML but 36-88% in MR studies. However, only few studies controlled for the presence of cerebrovascular risk factors. More recent studies - with improved techniques - revealed a higher frequency of (slight or moderate) WML in the (S)DAT group compared to controls. The prevalence of WML in VD patients was 75-97% in CT studies and about 100% in MR studies. Therefore, without the presence of WML, the diagnosis of VD is currently in doubt. A number of in vivo investigations proved consistently - and with different methods - that cerebral blood flow was reduced in WML regions. As shown in some studies the neuropathologic correlates of WML have in common that the relative tissue water content is increased: This includes inflammation, gliosis, complete and incomplete infarctions, dilation of the perivascular (Virchow-Robin) spaces with myelin atrophy. Thus the finding of WML in watershed areas can be understood. Three case reports serve to illustrate the problems pointed out. In conclusion, the occurrence of WML is an unspecific finding which is observed in up to 50% of the elderly. Diagnostic classification as "vascular lesions" or signs of "vascular encephalopathy" or VD based on CT or MRI alone, should not be made.

Aged↗

Global precedence in visual search? Not so fast: evidence instead for an oblique effect.

The evidence from an earlier report of global precedence in visual search is reexamined. Two new experiments are reported. The results of the first experiment indicate that the confusability of oblique orientations (a class-2 oblique effect) rather than global precedence was responsible for the earlier results. The results of the second experiment show that the effect critically depends on the presence of heterogeneous distractors rather than on differences in raw processing speed for different spatial scales. The possible role of symmetry is discussed.

Humans↗

Attentional skills in the acute phase following pediatric traumatic brain injury.

Only a limited number of studies have investigated attention following pediatric head-injury. The present study examined sustained attention and processing speed in a group of children who had sustained a mild (n = 27), moderate (n = 33) or severe (n = 16) traumatic brain injury (TBI). No significant differences were evident between the TBI groups on reaction time measures. Results did show that the severe TBI group exhibited greater deficits in the area of sustained attention, in comparison to children with mild and moderate injuries, in the acute stage following traumatic brain injury. This difficulty may impact on the future development of skills dependent on intact attentional capacity.

Attention↗

Factor analysis of computerized and traditional tests used in mild brain injury research.

The present study examines the relation between a set of computerized neuropsychological measures, Automated Neuropsychological Assessment Metrics (ANAM), and a set of traditional clinical neuropsychological tests. Both sets of tests have been employed in recent studies of mild brain injury. Factor analysis and stepwise regression indicate that both sets of tests measure similar underlying constructs of cognitive processing speed, resistance to interference, and working memory. The present findings indicate strong concordance between computerized and traditional neuropsychological measures and support the construct validity of ANAM and similar procedures.

Adolescent↗

A confirmatory factor analysis of the WISC-III in a clinical sample with cross-validation in the standardization sample.

Maximum likelihood confirmatory factor analysis was applied to the Wechsler Intelligence Scale for Children-Third Edition (WISC-III; Wechsler, 1991) data of a mixed clinical sample of 318 children. Analyses were designed to determine which of nine hypothesized oblique factor solutions could best explain intelligence as measured by the WISC-III in the clinical sample. Competing latent variable models were identified in previous studies, and results in the clinical sample were cross-validated by testing all models in the WISC-III standardization sample (n = 2200). Findings in both the clinical and standardization samples supported a five-factor model including Verbal Comprehension, Constructional Praxis, Visual Reasoning, Freedom from Distractibility, and Processing Speed factors. The Visual Reasoning factor was defined primarily by Picture Arrangement, whereas Mazes did not appear to improve model fit. Potential opportunities and pitfalls with regard to the interpretation of the proposed Visual Reasoning factor are discussed.

Adolescent↗

Performance characteristics of postacute traumatic brain injury patients on the WAIS-III and WMS-III.

Publication of the third editions of the Wechsler intelligence and memory batteries in 1997 created a need for research identifying Wechsler Adult Intelligence Scale-Third Edition/Wechsler Memory Scale-Third Edition (WAIS-III/WMS-III) profile patterns associated with neuropathology. The WAIS-III/WMS-III Technical Manual offers data on various diagnostic groups, including traumatic brain injury (TBI). Hawkins (1998) employed Technical Manual data to propose certain diagnostic guidelines. In order to validate the conclusions put forth by Hawkins as they apply to brain injury, we examined WAIS-III and WMS-III profiles in an independent sample of 46 TBI cases. As expected, the WAIS-III Processing Speed Index (PSI) was more sensitive to brain injury than other WAIS-III composites; and specific WAIS-III scores were stronger than certain WMS-III scores. On the other hand, the predicted relationship for WMS-III auditory and visual indexes was not found. The lack of specificity for TBI of the proposed index comparisons confirms the need to validate such hypotheses in independent samples.

Acute Disease↗

Neuropsychological characteristics of adults with ADHD: a comprehensive review of initial studies.

The role of neuropsychological evaluation in the diagnosis of adults with Attention-Deficit/Hyperactivity Disorder (ADHD) is a growing area of research and clinical interest. Our review of the literature indicates that adults with ADHD demonstrate subtle impairments on select measures of attention and executive functions, auditory-verbal list learning, and complex information processing speed relative to normal controls. The validity of these findings is nonetheless hampered by several limitations, including methodological and sample variability, a restricted range of interpretive techniques, and uncertain discriminant validity. Recommendations are offered to advance the cognitive and neurobehavioral understanding of this disorder and to enhance the utility of neuropsychological methods for diagnosis and management of adults with ADHD.

Adult↗

Practice effects on the WAIS-III across 3- and 6-month intervals.

Fifty-one participants (age M = 24.6; education M = 14.4 years) were administered the Wechsler Adult Intelligence Scale - Third Edition (WAIS-III) at baseline and at an interval of either 3 or 6 months later. Full Scale IQ (FSIQ), Verbal IQ (VIQ), Performance IQ (PIQ), Verbal Comprehension Index (VCI), Perceptual Organization Index (POI), and Processing Speed Index (PSI) scores improved significantly across time, whereas no significant change occurred on the Working Memory Index. Specifically, test scores increased approximately 3, 11, 6, 4, 8, and 7 points, respectively on the VIQ, PIQ, FSIQ, VCI, POI, and PSI for both groups. Notably, the degree of improvement was similar regardless of whether the inter-test interval was 3 or 6 months. These findings suggest that prior exposure to the WAIS-III yields considerable increases in test scores. Reliable change indices indicated that large confidence intervals might be expected. As such, users of the WAIS-III should interpret reevaluations across these intervals cautiously.

Adult↗

Wechsler Adult Intelligence Scale-Third Edition findings in relation to severity of brain injury in litigants.

WAIS-III findings were reported for 150 litigants, classified into three groups according to severity of traumatic brain injury (TBI), and a general population control group. There was a significant "dose response" relationship between TBI severity and all Index/IQ scores. Effect size was greatest for the Processing Speed Index (PSI). Between group differences were significant on all subtests except Information and Digit Span. Effect sizes were greatest for Digit Symbol, Symbol Search, Similarities, and Picture Arrangement. Relative to the control group, there was a significant difference for the Severe and Extremely Severe TBI groups on all IQ/Index scores and most subtests. The Moderate TBI group differed significantly on one Index (the PSI) and none of the subtests. Clinical implications of the findings are discussed in relation to the utility of the WAIS-III in assessing the cognitive sequelae of TBI, the use of current WAIS-III IQ scores to assess intelligence-memory discrepancies, WAIS-III short forms, and estimation of premorbid intelligence.

Adolescent↗

Reaction times are faster in HIV-seropositive patients on antiretroviral therapy: A preliminary report.

We evaluated subclinical mental and motor slowing in 142 HIV-seropositive patients without dementia, using computerized simple and choice reaction time tasks and self-report measures of psychological distress. Patients on antiretroviral therapy at the time of testing (n = 79) had significantly faster choice reaction times (p < 0.05), indicating faster mental processing speed, than untreated patients (n = 63). These faster RTs could not be attributed to differences in age, education, risk factors, degree of immunosuppression, substance abuse history, peripheral neuropathy, or psychological distress. Reaction time tasks should be investigated further as potential outcome measures in clinical trials, particularly for subjects with few or no overt cognitive deficits.

Adult↗

Neuropsychological effects of prefrontal slow rTMS in normal volunteers: a double-blind sham-controlled study.

Recent reports have suggested that repetitive transcranial magnetic stimulation (rTMS) is effective in major depression. Unlike ECT, rTMS does not involve a seizure and is associated with minimal side-effects, including cognitive difficulties. However, the effect of rTMS on cognitive functioning has not been systematically evaluated. This study was designed to examine the neuropsychological effects of slow rTMS in normal volunteers. Forty-six normal volunteers were randomly assigned to receive one session of right (N = 16) or left prefrontal (N = 15), or sham (N = 15) rTMS at 1 HZ. Patients were assessed before and after stimulation by a computerized neurospychological battery. All three groups showed significant improvement over time in processing speed (reaction time) and efficiency (correct responses per unit of time). However, no time by group interaction was found for any of the neuropsychological tests. These findings suggest that a single session of slow rTMS does not interfere with neurospychological functioning in normal volunteers, supporting clinical reports of no adverse cognitive effects.

Adult↗

A confirmatory factor analysis of the WAIS-III in patients with traumatic brain injury.

Maximum likelihood confirmatory factor analysis was performed on the WAIS-III data of a sample of 166 patients with traumatic brain injury (TBI). Four competing hypothetical models were tested for model fit and parsimony. A four-factor model composed of Verbal Comprehension, Perceptual Organization, Working Memory, and Processing Speed, identical to that proposed for the standardization sample, provided the best fit to the clinical data. The results support the construct validity of these four factors in patients with TBI.

Adolescent↗