PubMed Health⌕ Search

Biomedical subjects

B Landau

Publications and source records attributed to B Landau.

At least 19 recordsLinked to original sources
PubMed2001

Spatial language and spatial representation: a cross-linguistic comparison.

We examined the relationship between spatial language and spatial memory by comparing native English, Japanese, and Korean speakers' naming of spatial locations and their spatial memory for the same set of locations. We focused on two kinds of spatial organization: axial structure of the reference object, and contact/support with respect to its surface. The results of two language (naming) tasks showed similar organization across the three language groups in terms of axial structure, but differences in organization in terms of contact/support. In contrast, the results of two memory tasks were the same across language groups for both axial structure and contact/support. Moreover, the relationship between spatial language and spatial memory in the two sets of tasks did not show a straightforward isomorphism between the two systems. We conclude that spatial language and spatial memory engage the same kinds of spatial properties, suggesting similarity in the foundations of the two systems. However, the two systems appear to be partially independent: the preservation of particular spatial properties was not mandatory across languages, nor across memory tasks, and cross-linguistic differences in spatial language did not lead to differences in the non-linguistic encoding of location. We speculate that the similarity in linguistic and non-linguistic representations of space may emerge as a functional consequence of negotiating the spatial world.

Analysis of Variance↗
PubMed1996

Naming in young children: a dumb attentional mechanism?

Previous studies have shown that young children selectively attend to some object properties and ignore others when generalizing a newly learned object name. Moreover, the specific properties children attend to depend on the stimulus and task context. The present study tested an attentional account: that children's feature selection in name generalization is guided by non-strategic attentional processes that are minimally influenced by new conceptual information presented in the task. Four experiments presented 3-year-old children and adults with novel artifacts consisting of distinctive base objects with appended parts. In a Name condition, subjects were asked whether test objects had the same name as the exemplar. In a Similarity condition, subjects made similarity judgments for the same objects. Subjects in two experiments were shown a function for either the base object or the parts. Both adults' naming and similarity judgments were influenced by the functional information. Children's similarity judgments were also influenced by the functions. However, children's naming was immune to influence from information about function. Instead, children's feature selection in naming was shifted only by changes in the relative salience of base objects and parts. The results are consistent with the idea that dumb attentional processes are responsible for young children's smart generalizations of novel words to new instances. Potential mechanisms to explain these findings are discussed.

Adult↗
PubMed1993

Tentorial and posterior cranial fossa meningiomas: operative results and long-term follow-up: experience with twenty-six cases.

In spite of significant recent advancements in imaging technology, monitoring [12] and surgical techniques [1,5,7,18,21,24], complete and safe removal of tentorial and posterior fossa meningiomas remains a formidable challenge for most neurosurgeons [6,8,9,14,15,17]. This paper reviews our experience with 28 patients with tentorial and posterior fossa meningiomas.

Adult↗
PubMed1993

Neuromodulation techniques for medically refractory chronic pain.

Advances in our knowledge of the physiology of pain transmission and modulation have created new surgical options for the control of chronic pain. The pain modulation network can be activated by administration of spinal opiates or by electrical stimulation of the nervous system with transcutaneous, peripheral nerve, spinal cord, and deep brain stimulation. The theoretical basis and the clinical applications of neurostimulation for the treatment of medically intractable chronic pain are reviewed.

Chronic Disease↗
PubMed1991

Spatial representation of objects in the young blind child.

Four experiments investigated the young blind child's ability to discover, construct and transform representations of objects, in particular those that preserve the spatial relationships among object parts. Experiment 1 showed that three 18-36-month-old blind children systematically explored novel objects using distinctive haptic manipulations linked to novel shape versus texture. Experiments 2, 3 and 4 pursued a single blind child's ability to represent and transform the spatial configurations of objects. By 2 1/2 years, this child was able to rapidly recognize and identify familiar geometric figures following brief exploration (Experiment 2). By 3 years, she was able to recognize novel objects under 180 degree rotations when their configurations differed from distractors only in the spatial relationships holding among object parts (Experiment 3). At this age, she was also able to infer the locations corresponding to spatial parts of novel objects (the top, bottom, front, back and side) when the objects were upright or rotated, defined only by the location of a single "anchor" term that established their orientation (Experiment 4). In all cases, the blind child's performance was quite similar to that of sighted controls. The results indicate that visual experience is not necessary for the early natural emergence of the capacity to represent and transform spatial descriptions of objects.

Attention↗
PubMed1991

Object properties and knowledge in early lexical learning.

The ease with which young children learn object nouns suggests that they possess strategies to identify properties critical to lexical category membership. In previous work, young children used a same-shape criterion to extend new count nouns. The present research tested the generality of this shape bias. 2- and 3-year-olds were asked either to extend a novel count noun to new instances, or to choose unnamed objects to go together. The objects varied in shape, size, and texture. For half of the subjects, the objects had eyes--a property strongly associated with certain material kinds. If young children know this association, they should attend to texture as well as shape in classifying objects with eyes. With named objects only, both 2- and 3-year-old children classified eyeless objects by shape and objects with eyes by both shape and texture. The results suggest that very young children possess considerable knowledge about conditional relations between kinds of perceptual properties. Knowledge of such conditional relations may aid children in forming new categories and thus in discovering new word meanings.

Attention↗
PubMed1990

A partial solution to the homonym problem: parents' linguistic input to young children.

During early word learning, children may assume a unique form-meaning relationship: that a unique form corresponds to each meaning (Clark, 1987) and vice versa (Slobin, 1985). Homonyms appear to violate this one-to-one mapping, and therefore might prove problematic; for example, all things labeled bat might be put into the odd category 'things that fly and are used to play ball.' We asked whether parents' descriptions of homonyms to their young children provide linguistic information that could help children to differentiate conceptually and linguistically these cases. Fifteen parents described pictured sets of concrete object homonyms and categorically related objects to their young children. Parents described homonyms by using explicit statements of category inclusion, subordinate forms (compounds, e.g., kiwi-bird), and specific forms that flagged the unusual homonym relationship. Parents especially provided distinctive alternating forms for homonym pairs (e.g., iceskate vs. skate-fish) suggesting that they were attempting to preserve the unique form-meaning relationship violated by homonyms. We discuss how such linguistic information might be used by children to differentiate homonyms.

Child, Preschool↗
PubMed1983

ATP contents of human semen, seminal plasma and isolated sperm at time intervals after ejaculation.

1. ATP was estimated in 105 samples of human semen, seminal plasma and sperm of normozoospermic and oligozoospermic origins at time intervals after ejaculation. 2. In semen with sperm counts up to 40 millions per ml and in seminal plasma, ATP levels were lower than in specimens with higher sperm counts. 3. In isolated sperm, the ATP content decreased with the increase in sperm density. 4. The decrease in ATP after 24 hr was the highest in sperm, lower in semen and the lowest in seminal plasma, being maximal in specimens with high sperm counts.

Adenosine Triphosphate↗
PubMed1982

The influence of thyroid function on serum lipid profile.

Serum triglycerides, cholesterol, HDL-C and LDL-C levels as well as the LDL/HDL cholesterol ratio were determined in 11 patients suffering from hyperthyroidism and 7 patients suffering from hypothyroidism, and compared with those of 19 sex-and age-matched controls. In hypothyroidism a net increase of all lipid values was observed. In hyperthyroidism cholesterol and LDL-C values were reduced while those of the triglycerides and HDL-C were unchanged as compared with controls. The LDL/HDL cholesterol ratio in either group of patients was lower than in controls, the lowest being observed in thyrotoxicosis.

Aged↗
PubMed1982

Vitamin A and beta-carotene content of seminal fluid and sperm of normospermic and oligozoospermic men.

Beta-carotene and vitamin A were estimated in 125 specimens of human seminal fluid and spermatozoa. In 72 of the specimens triiodothyronine, tetraiodothyronine, and T4-binding globulin were also determined. Vitamin A in seminal fluid increased from 10.4+/-l.8 microgram (SE) in severe oligozoospermia up to 19.1+/-2.5 microgram/100ml in specimens with high sperm densities. In spermatozoa, however, there was a trend for a decrease in vitamin content from 2.1+/-0.8 to 0.2 +/-0.07 microgram/108. In the majority of cases beta-carotene was undetectable and, when present, the levels were much lower than those of vitamin A. The amounts of triiodothyronine and tetraiodothyronine in seminal fluid were 0.19+/-0.03 ng/ml and 1.1+/-0.18 microgram/100ml, respectively. No correlation was found between levels of both hormones and quality of seminal fluid. T4-binding globulin was either very low or undetectable.

Alpha-Globulins↗
PubMed1982

Inhibition and enhancement of macrophage migration in the presence of lymphocytes and seminal fluid of men with fertility disorders.

Macrophage migration inhibition factor (MIF) towards autologous seminal fluid was studied in 29 infertile men, 16 of whom were also examined towards normal seminal fluid. In 10 patients, inhibition of macrophage migration was observed in the presence of 50 microgram of protein of autologous semen sonicates. Nine patients had enhanced macrophage migration in the presence of 5 microgram protein. Macrophage enhancement was more antigen dependent than the migration inhibition. In all patients seminal abnormalities were observed, being milder in the patients whose lymphocytes enhanced macrophage migration.

Humans↗