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P Satz

Publications and source records attributed to P Satz.

At least 127 records · Page 7Linked to original sources
PubMed1984

Pathological left-handedness and ambiguous handedness: a new explanatory model.

A new model is presented which attempts to explain three pathological handedness phenotypes: pathological left-handedness (PLH), pathological right-handedness (PRH) and ambiguous handedness (AH). Revisions in the original model of PLH were prompted in order to account for reports of a raised incidence of both manifest left-handedness and AH in more severely retarded and/or brain-injured populations--namely, autistic. The new model generates specific predictions on the likelihood of different etiological subgroups within these disorders.

Autistic Disorder↗
PubMed1984

Dichotic listening ear asymmetry: patterns of longitudinal development.

Dichotic listening research with children has continued to be prevalent although numerous authors have described both theoretical and methodological limitations with traditional dichotic listening free-recall paradigms. The present research adds to this growing skepticism by reanalyzing two major longitudinal studies of children's ear asymmetries. These two studies, based in different countries (United States, Holland), utilized highly similar paradigms (free-recall digits), subjects (males), and age levels (kindergarten and second and fifth grade). The questions of ear advantage development, patterns of ear advantages, and the relationship between dichotic listening performance and reading skills are addressed from the multiple statistical methodologies represented in the literature. From these analyses, support for all of the major hypotheses regarding the developmental patterns of dichotic listening performances could be obtained from the same data samples. The use of traditional free-recall dichotic listening paradigms are not recommended for use with children. The implications for future research are discussed.

Child↗
PubMed1984

On the statistical estimation of speech-organization distributions from aphasia data.

Statistical methods of estimating speech-organization distributions from aphasia data are presented. Under certain assumptions, estimators for the proportions of individuals with unilateral right-hemisphere speech, unilateral left-hemisphere speech and bilateral speech organization are derived, and the large-sample properties of these estimators are presented. It is shown that useful results can be obtained when the most questionable assumption is relaxed. The general methodology is presented in terms of a specific example--the estimation of speech organization distributions of right- and left-handed adults across the three speech types. Under the relaxed assumptions a test of the hypothesis that all left-handers are unilaterally organized is derived. Conservative bounds on the proportions of unilaterally organized (left- and right-hemisphere) and bilaterally organized left-handers are also derived. As an illustration, the results are applied to aphasia-incidence data from the literature. Several uncertainties and inadequacies of the available data are discussed. Although minor modifications of the present methods might be required for other examples, the main ideas would be the same.

Adult↗
PubMed1983

The development of handedness and dichotic ear listening asymmetries in relation to school achievement: a longitudinal study.

To assess the development of dichotic ear asymmetries and handedness, 208 male school children were evaluated in kindergarten and at Grades 2 and 5 (ages 66, 92, and 130 months of age, respectively) with a dichotic listening task and a hand preference test. The Wide Range Achievement Test (WRAT) also was administered at each of the three grade levels. There was significant variability in handedness scores over time only for those subjects whose scores at initial testing, that is, in kindergarten, identified them as non-right-handers. Both right and left handers had a significant increase in dichotic listening scores over time; however, only right handers had a significant right ear advantage at each evaluation. Regression analyses showed that combined hand preference scores and ear recall scores at each probe when combined accounted for almost 44% of the variance in WRAT achievement scores at Grade 5. Ear asymmetry scores, however, were not predictive of school achievement.

Achievement↗
PubMed1982

Aphasia and speech organization in children.

A long-standing controversy concerns whether lateralized cerebral specialization for speech and language is present at the time of language origins (developmental invariance) or whether it gradually develops from initial bilaterality (developmental progression). Thus controversy is complicated by conflicting reports of the incidence of childhood aphasia. The discrepancies are largely due to one early study. When methods for estimating speech organization distributions are applied to later studies, the developmental invariance position is supported.

Adolescent↗
PubMed1981

Neuropsychology and cluster analysis: potentials and problems.

This report presents a selective overview of the cluster analysis literature and its potential uses in neuropsychology. In addition, an actual problem involving data from the Florida Longitudinal Project is presented to provide a practical example of many of the processes and problems involved in cluster analytic techniques. It is hoped that the reader will gain a theoretical and practical understanding of such methods and their potential usefulness in neuropsychology and other related areas.

Child↗
PubMed1979

A test of some models of hemispheric speech organization in the left- and right-handed.

A new method generates specific predictions concerning the expected frequencies of aphasia after unilateral injury to the brain in the left- and right-handed. These predictions are then compared with the observed data for all known studies between 1935 and 1973 to derive the best-fitting model of hemispheric speech lateralization in the left- and right-handed.

Aphasia↗