Pseudoneglect: a review and meta-analysis of performance factors in line bisection tasks.

plex diseases, 5,6 including atherosclerosis. Although there is no clinical evidence of a role for the hemostatic system in the progression of atherosclerosis, ample experimental data indicate that platelets and the coagulation system are important determinants of both atherogenesis and ath

https://www.nejm.org/doi/suppl/10.1056/NEJMra1011670/suppl_file/nejmra1011670_appendix.pdf

The Hemostatic System as a Modulator of Atherosclerosis

The spatial location of an object can be represented in the brain with respect to different classes of reference frames, either relative to or independent of the subject's position. We used functional magnetic resonance imaging to identify regions of the healthy human brain subserving mainly egocentric or allocentric (object-based) coordinates by asking subjects to judge the location of a visual stimulus with respect to either their body or an object. A color-judgement task, matched for stimuli, difficulty, motor and oculomotor responses, was used as a control. We identified a bilateral, though mainly right-hemisphere based, fronto-parietal network involved in egocentric processing. A subset of these regions, including a much less extensive unilateral, right fronto-parietal network, was found to be active during object-based processing. The right-hemisphere lateralization and the partial superposition of the egocentric and the object-based networks is discussed in the light of neuropsychological findings in brain-damaged patients with unilateral spatial neglect and of neurophysiological studies in the monkey.

The neural basis of egocentric and allocentric coding of space in humans: a functional magnetic resonance study

Background—Several hemostatic and rheological factors have been associated with incident cardiovascular events. However, there have been no reports on the relationship of rheological factors with e...

Blood Viscosity and Elevated Carotid Intima-Media Thickness in Men and Women The Edinburgh Artery Study

Localized repetitive transcranial magnetic stimulation was used to disrupt visuospatial perception in the near and far space of six healthy volunteer subjects. In addition to the baseline condition, they were stimulated over the right posterior parietal cortex, the right or left dorsal occipital cortex or the right ventral occipital cortex, during the brief presentation of a transected horizontal line. Subjects had to indicate whether the part of the line to the left or right of the transection appeared longer. The stimulus display was back-projected on a screen at a viewing distance of either 50 or 150 cm (‘near’ and ‘far’ space, respectively). Reaction times and choices were measured. In a forced-choice paradigm, subjects showed ‘pseudoneglect’, the natural tendency of neurologically intact subjects to perceive the left side of a centrally transected line as slightly longer than the right. These errors occurred more for lines in near space than for lines in far space. Magnetic stimulation of the right posterior parietal cortex or the right ventral occipital lobe selectively induced a significant shift to the right in the perceived midpoint for near- and far-space lines, respectively. The results reproduced in normal subjects the dissociation between neglect in near and far space that has been described in patients with different right-hemisphere lesions. This dissociation supports the contention that there is a dorsal/near space–ventral/far space segregation of processing in the visual system which reflects the behavioural goals of the two putative visual streams.

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Spatial neglect in near and far space investigated by repetitive transcranial magnetic stimulation.

The aim of this study was to point out a hemisphere asymmetry in focal brain-damaged patients and a hand asymmetry in normals on halving binocularly a horizontal line. 50 left hemisphere and 53 right hemisphere patients (both subdivided by presence/absence of visual field defect) and 50 controls (divided by the hand they used to carry out the task) were employed. 4 differently long segments made up the test material and the error scores with respect to the geometric midpoint were worked out by means of parametric statistical procedures. It turned out that: (i) healthy subjects committed a mean leftward displacement, regardless of the hand they used. All the same, only the halving error committed by the right hand is significant keeping as reference the geometric midpoint of the segment; (ii) left and right hemisphere-damaged patients committed halving errors, that are opposite in direction, leftward for the former and rightward for the latter; (iii) the behaviour of right patients with visual field defects is the only to be significantly different from that of the corresponding controls. Our findings point to prevailing importance of the right hemisphere mainly of its posterior areas, in the halving task.

Halving a horizontal segment: a study on hemisphere-damaged patients with cerebral focal lesions.

The effectiveness of cerebral antiedema agents in stroke has been questioned. Animal and clinical work is inconclusive about steroids and osmotic drugs. A retrospective study of a continuous series of 227 stroke patients treated in the acute stage (some with dexamethasone alone, some with dexamethasone plus hyperosmotic mannitol infusions, and some without antiedema therapy) showed no significant difference in the ten-day survival rate. On this criterion, there is no ground for the systematic use of such agents against this type of brain swelling.

https://www.ahajournals.org/doi/pdf/10.1161/01.STR.6.4.353

Therapy against brain swelling in stroke patients. A retrospective clinical study on 227 patients.

Background and Purpose Increases in common carotid intima-media thickness (CC-IMT), as measured by B-mode ultrasonography, have been widely used in both population studies and clinical trials in the search for risk factors for early atherosclerosis progression and have been found to correlate with age and with high concentrations of low-density lipoprotein cholesterol, leukocytes, and hemoglobin We have now investigated the relation between several baseline hemostatic and conventional risk factors and CC-IMT changes over 16 months in 64 patients with peripheral arterial disease randomly selected from the prospective PLAT study series Methods Samples from 24 patients (375%) who showed increases in CC-IMT during the follow-up period were compared with those from 40 (625%) in whom CC-IMT remained unchanged Results Baseline conventional risk factors and coagulation variables were similar in the two groups except for higher plasma concentrations of von Willebrand factor (vWF) (1783±536% versus 1412±53

/pdf/relation-between-hemostatic-variables-and-increase-of-common-4jdqlcf3vs.pdf

Relation Between Hemostatic Variables and Increase of Common Carotid Intima-Media Thickness in Patients With Peripheral Arterial Disease

A prospective study of 93 acute stroke patients randomly selected by type of antiedema treatment given (hypertonic glicerol infusion plus dexamethasone versus dexamethasone alone) failed to elicit any statistically significant difference between the two treatments on survival rates and quality of survival 7 and 30 days after the stroke.

A. Colombo

Papers

Halving a horizontal segment: a study on hemisphere-damaged patients with cerebral focal lesions.

Therapy against brain swelling in stroke patients. A retrospective clinical study on 227 patients.

Relation Between Hemostatic Variables and Increase of Common Carotid Intima-Media Thickness in Patients With Peripheral Arterial Disease

Association of glycerol to dexamethasone in treatment of stroke patients.

Anti-oedema treatment of completed stroke