Visual perception of line direction in patients with unilateral brain disease

The accuracy of identifying the slope of briefly exposed lines was assessed in patients with lesions of the left or right hemisphere and in a group of control patients without history or evidence of brain disease. The frequency of impaired performance was remarkably high in the patients with right hemisphere lesions. In contrast, the patients with left hemisphere lesions did not perform differently from the control group. Visual field defect, aphasic disorder, and age were not related to performance level. The striking interhemispheric difference in performance on this visuospatial task suggests its further development for clinicodiagnostic purposes.

Facial recognition 1990

A review of recent studies of prosopagnosia suggests that the weight of evidence has shifted in favor of regarding it as a disability that can be produced by a right hemisphere lesion alone even though bilateral disease remains the more frequent anatomical basis. It is possible that prosopagnosia resulting from a right hemisphere lesion occurs only within the context of some atypical condition of the left hemisphere. "Types" of prosopagnosia continue to be postulated and the "identification of individuality" hypothesis continues to be advanced. Autonomic and covert recognition studies of prosopagnosic patients have described a new dimension in facial identification. Right hemisphere dominance for the discrimination of unfamiliar faces in non-aphasic patients has been confirmed but the performances of left-hemisphere damaged aphasic patients has still not been fully investigated. New developments include the study of developmental prosopagnosia and novel applications of test of facial discrimination.

Robust, routine haematology reference ranges for healthy adults

Accurate, reliable laboratory reference ranges are essential for effective clinical evaluation and monitoring. We present robust reference ranges established for haematology, coagulation and haematinic parameters using the Sysmex XE 2100, CA 1500 and Beckman-Coulter Access analysers. Blood samples were taken from 250 healthy laboratory personnel and routine haematology, coagulation and haematinic parameter analysis performed. Our data represent findings from an extensive study to establish reference ranges in healthy adults.

Reaction time in brain disease: some reflections

Two factors associated with measurements of RT, viz., the role of task complexity and the relationship of RT to locus and size of lesion, are considered. Analysis of the literature suggests that the two factors are interrelated. There appears to be a trend for the complexity gradient to be steeper in patients with widespread brain damage than in those with focal lesions. Although simple RT is generally reported to be slower in patients with right hemisphere lesions, there are indications that complex RT may be slower in patients with left hemisphere lesions. The multiplicity of procedures utilized in different studies is probably responsible for some of the inconsistent findings in the literature. Explicit definition of these procedures and the employment of combinations of them should resolve these inconsistent findings and help to elucidate the relationship between RT and cerebral status.

Visuospatial judgment and right hemisphere disease

The performances of patients with stroke-produced unilateral hemispheric lesions on a test requiring the identification of lines were examined in the light of a recent report that contradicted previous observations. The study confirmed the results of earlier studies that patients with lesions of the right hemisphere show a remarkably high frequency of defective performances while those with lesions of the left hemisphere do not. Possible reasons for findings that deviate from this rule are discussed.

Hemispheric dominance before Broca

Analysis of early medical literature indicates that considerable evidence for a specific association between speech disorder and disease of the left hemisphere was incorporated within it. The diverse reasons for the failure of clinicians to perceive the association are discussed and the approach of Marc Dax to the question is described.

Suppression of a field population of houseflies with Spalangia endius

Sustained releases of the microhymenopteran pupal parasite Spalangia endius, at a commercial poultry installation in north Florida, completely suppressed a population of houseflies with in 35 days.

The Hécaen-Zangwill legacy: hemispheric dominance examined

The research of Henry Hécaen and Oliver Zangwill on patients with unilateral brain lesions in the later 1940s and early 1950s ushered in the modern era of investigation of hemispheric cerebral dominance. The field of inquiry expanded far beyond language and visual perception to encompass audition, somesthesis, motor performance, attentional processes, emotionality, and psychiatric disorders. The hundreds of studies dealing with the topic indicate that hemispheric dominance is not an all-or-none phenomenon and that, to some degree, it is an unstable phenomenon dependent upon bihemispheric factors. The basic cognitive processes that are preferentially mediated by each hemisphere and the factors that produce changes in performance still require adequate definition.

Red cell folate and plasma homocysteine in preterm infants

BACKGROUND

The supplementation of preterm infants with folic acid is routine practice in many neonatal units. However, the advent of preterm formula milks and breast milk fortifiers have increased folic acid intake. We measured red cell folate in preterm infants who received preterm formula milks and breast milk fortifiers to determine whether additional folic acid supplementation was still required. A potential benefit of folic acid supplementation is reduction of plasma total homocysteine (tHcy). tHcy appears to have a linear association with the risk of atherothrombotic vascular events in adults but its role in intraventricular haemorrhage and associated white matter damage in preterm infants is not known. As there is little information regarding tHcy in preterm infants, we also measured tHcy in this study.

METHODS

Red cell folate and tHcy were measured at 1 and 4 weeks of age and before discharge in 28 consecutive infants <34 weeks' gestation. Factors which may have affected folate and homocysteine status were recorded.

RESULTS

Red cell folate ranged between 266 and 1,513 ng/ml and deficiency (<140 ng/ml) was not observed in any sample. Red cell folate concentration tended to increase with increasing age. tHcy ranged from 0.8 to 12.2 micromol/l and fell within the 'normal' range for fasting adults.

CONCLUSIONS

Preterm formula milks and breast milk fortifiers provide sufficient folic acid to prevent folate deficiency in preterm infants. Although tHcy fell within the 'normal' range for fasting adults, more research is needed to determine optimal concentration of tHcy for preterm infants.

Clinical neuropsychology: 1960-1990

Clinical neuropsychology has made significant progress during the past 30 years. Practice and research have expanded remarkably in scope and are more incisive and more highly focused. There has been an explosive development of test methods but clinical neuropsychologists have yet to take full advantage of them. An effort should be made to combine the strengths of the "fixed battery" and "flexible" approaches to assessment. Further advances in neuropsychological assessment will come about only to the degree that they are linked to evolving concepts of brain-behavior relationships. Neuropsychologists now require a deeper understanding of basic neuroscience and cognitive psychology than was true in the past. Steps should be taken to insure that training to achieve that understanding is provided to the upcoming generation of neuropsychologists.

Visuospatial judgment: a cross-national comparison

Two samples of American and Italian 8 to 12 year-old children were compared for their performance on the Judgment of Spatial Orientation Test. No group difference emerged and, consequently, the same normative standards for performance can be applied in both countries. In both groups males performed better than females.

Four neuropsychologists

The achievements of Henry Hécaen, Oliver Zangwill, Hans-Lukas Teuber, and Norman Geschwind are reviewed. Each made an enormously significant contribution to the form and content of the field of neuropsychology as we know it today.

medpie: an information extraction package for medical message board posts

SUMMARY

We have developed medpie, a software package for preparing medical message board corpora and extracting patient mentions and statistics for drugs, herbs and adverse effects experienced from them. The package is divided into web-crawling, HTML-cleaning, de-identification and information extraction modules. It also includes a sample controlled vocabulary of drugs, herbs and adverse effect terms.

AVAILABILITY

http://www.cis.upenn.edu/~ungar/medpie.zip.

DEPENDENCIES

Python 2.6 or 2.7.

Visual reaction time as a function of locus, area, and complexity of stimulus

Reaction time (RT) of normal subjects to square-wave gratings of two different frequencies were related to locus of presentation, area, and stimulus complexity. Each frequency was presented to either side of the horizontal meridian (half size stimulus) or both sides stimultaneously (full size stimulus). The two different frequencies were also flashed simultaneously to both hemifields (compound stimulus). Stimulus position affected RT with the 1 c/deg stimulus, RT being faster for the lower hemifield. With presentation on both sides of the horizontal median simultaneously or of the two spatial frequencies, the resulting RT was equal to that of the faster component. Implications of the results for the functional organization of the visual system are discussed.

Cefotaxime as the potential cause of transient acquired von Willebrand syndrome

Acquired von Willebrand syndrome (AvWS) is a relatively rare bleeding disorder. It has been reported in association with myeloproliferative disorders, autoimmune diseases, plasma cell dyscrasias and certain drugs. Cefotaxime is a third generation cephalosporin widely used for surgical prophylaxis and as empirical treatment of bacterial meningitis. We report a case of a transient AvWS in association with cefotaxime therapy.

Haemorrhagic transformation of cerebral infarction in an AIDS patient--thrombophilia screen essential!

Patients with advanced HIV disease with low CD4 count are more prone to thrombo-embolism and various predisposing factors have been identified. These include the presence of anticardiolipin antibodies and the lupus anticoagulant, deficiencies of proteins C and S, heparin co-factor II and antithrombin. Increased levels of Von Willebrand factor and d-dimers have also been linked with thrombo-embolism, as has the presence of concurrent infections and malignancies. We report a case of an AIDS patient who presented with acute hemiparesis. He was severely immunosuppressed. Computed tomography of the head confirmed cerebral infarction with haemorrhagic transformation. He had no known risk factors apart from being severely immunocompromised and had high anticardiolipin antibodies and low free protein S.

Neuropsychological test development and normative data on Hispanics

The development of culturally relevant psychological assessment tools and intervention procedures has not been commensurate with the rate of Hispanic population growth in the United States. The development of valid and reliable test measures for the assessment of this population must be based on empirical investigations. In this article, we present normative data on multiple measures from the Benton Laboratory and the Wisconsin Card Sorting Test. Results revealed equivalent findings for our Hispanic subjects and the English-speaking samples utilized in the original normative studies within the United States. We additionally review current trends and specific problems encountered in neuropsychological research with Hispanics, and suggest guidelines and directions for future research.