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Biomedical subjects

M H Birnbaum

Publications and source records attributed to M H Birnbaum.

At least 19 recordsLinked to original sources
PubMed1990

Judgments of proportions.

This study investigated the processes that underlie estimates of relative frequency. Ss performed 4 tasks using the same stimuli (squares containing black and white dots); they judged "percentages" of white dots, "percentages" of black dots, "ratios" of black dots to white dots, and "differences" between the number of black and white dots. Results were consistent with the theory that Ss used the instructed operations with the same scale values in all tasks. Despite the use of the correct operation, Ss consistently overestimated small proportions and underestimated large proportions. Variations in the distributions of actual proportions affected the extent to which Ss overestimated small proportions and underestimated large proportions in the direction predicted by range-frequency theory. Results suggest that proportion judgments, and by analogy probability judgments, should not be taken at face value.

Adult↗
PubMed1989

Two operations for "ratios" and "differences" of distances on the mental map.

Ss judged "ratios of distances" and "differences of distances" between pairs of U.S. cities. Results fit the theory that Ss used two comparison processes as instructed. A ratio scale of distances between cities was constructed from the 2 rank orders. From this scale, an interval scale of the city locations on an east-west continuum was derived. This scale agrees with the subtractive model fit to "ratios" and "differences" of easterliness and westerliness, and it also agrees with multidimensional scaling of judged distances between cities. These findings are consistent with the theory that Ss use subtraction when instructed to judge either "ratios" or "differences," but that they can use both ratio and difference operations when the stimuli (in this case, distances) constitute a ratio scale on the subjective continuum.

Adult↗
PubMed1985

An esophoric shift associated with sustained fixation.

Some subjects show a progressive increase in their near phoria, in the direction of more esophoria, when the test is repeated. Eighteen of 100 subjects showed 5 delta or more esophoric shift. This result suggests that similar phoria changes may occur during prolonged intensive nearwork. The results reported are not the same as prism adaptation because the esophoric shift was found with dissociated targets. Autonomic arousal with sympathetic activation associated with heightened attention and concentration is proposed as the mechanism.

Accommodation, Ocular↗
PubMed1985

Nearpoint visual stress: clinical implications.

A physiological model of nearpoint stress, based on autonomic arousal, was presented in a companion paper. This paper deals with clinical implications of the nearpoint stress model, including clinical manifestations, adaptive responses to nearpoint stress, and management of nearpoint stress-induced vision disorders.

Accommodation, Ocular↗
PubMed1984

Weight of evidence supports one operation for "ratios" and "differences" of heaviness.

This paper investigates an apparent contradiction between recent studies of "ratios" and "differences" of heaviness. Birnbaum and Veit (1974) found a single rank order for judgments in the two tasks, whereas Rule, Curtis, and Mullin (1981), who used a different stimulus set, procedure, and experimental design, reported two orders. To investigate the cause of this discrepancy, the present study manipulated the experimental design using the same stimuli and procedure as Rule et al. (1981). In one experiment (within-subject designs), each subject judged all combinations of the standard and comparison stimulus; in the other experiment (between-subjects designs) each subject received only one standard, and different groups of subjects were given different standards. "Ratios" and "differences" of heaviness were monotonically related for the majority of subjects who judged all combinations of standards and comparisons. Variations in the modulus and response examples did not affect the rank order of "ratios" within subjects. These results suggest that the contradiction in results is due to the difference in experimental design rather than differences in stimuli or procedure. In the between-subjects designs, the rank order of the "ratio" judgments depended on the standards and examples. Both previous and present results are consistent with the theory that subjects use one operation, subtraction, for both tasks and that the judgment function varies with between-subjects manipulations of the standard, examples, and modulus.

Humans↗
PubMed1982

Loci of contextual effects in judgment.

Three experiments investigated the loci of contextual effects in judgment. Experiment 1 demonstrated the effect of stimulus spacing on category ratings and magnitude estimations of the darkness of dot patterns. Variations in the stimulus spacing were shown to affect both category ratings and magnitude estimations in a similar fashion. Experiment 2 was designed to determine whether contextual effects due to stimulus spacing influence the scale values or the judgment function. Subjects judged "differences" and "ratios" of the subjective darkness of dot patterns. Differences in mean judgments of single stimuli from Experiment 1 did not predict the rank order of judged "differences" and "ratios" from Experiment 2. The estimated scale values of the stimuli appeared to be independent of stimulus spacing. These findings suggest that contextual effects due to the stimulus spacing occur in the judgment function for within-modality judgments. Experiment 3 examined contextual effects in cross-modality judgments. Stimulus spacing and stimulus range were manipulated for "difference" and "total" judgments. Unlike the within-modality results, the stimulus range and spacing influenced the scale values. A contextual theory of within- and cross-modality judgment is presented.

Discrimination Learning↗
PubMed1979

Management of the low myopia pediatric patient.

A review of the literature on myopia etiology indicates that environmental factors, particularly those related to nearpoint use of the eyes, appear to play a significant role. A regimen is described for control of environmental factors producing myopic progression, including use of bifocal lenses to reduce accomodative demand, visual hygiene to foster accommodative relaxation, and vision training to develop adequate accommodative skills and freedom of action between accommodative and convergence systems.

Accommodation, Ocular↗
PubMed1978

Holistic aspects of visual style: a hemispheric model with implications for vision therapy.

A model is proposed relating styles of cognition and perception, modes of consciousness, and cerebral hemispheric function to visual styles and visual problems. The implications of such a model for management of vision problems are discussed. It is recommended that training for the central, eso patient emphasize procedures which are spatial, holistic, peripheral, simultaneous, and involve the use of imagery. For the peripheral, exo patient, treatment techniques should involve sequence and rhythm, analytical processing, discrimination of fine differences, and attention to detail in central areas of the visual field.

Child↗
PubMed1978

Functional relationship between myopia, accommodative stress and against-the-rule astigmia: a hypothesis.

A model is proposed to explain the well-established tendency for against-the-rule astigmatism to precede and be predictive of the later development of myopia. It is hypothesized that the against-the-rule astigmatism is a functional adaptation to reduce near point stress by permitting reduced accommodative output (increased lag of accommodation) while maintaining resolution for the primarily vertically-oriented characters of the English language.

Accommodation, Ocular↗
PubMed1977

The role of the trainer in visual training.

The role of the trainer in assisting the patient to internalize changes in his visual process is discussed. Emphasis is placed on two aspects: (1) making the patient aware of the nature of the change in process desired, and (2) making the patient aware that the phenomena which he observes during vision training techniques, such as blurring and clearing, diplopia, and suppression of training targets, which he may perceive as occurring esternally reflections of his visual process and as such, are subject to his control.

Child↗
PubMed1977

Success in ambylopia therapy as a function of age: a literature survey.

It is frequently stated that amblyopia is not correctable after the age of 6 years. Many practitioners report marked success for older patients. To evaluate these conflicting reports, we analyzed the results from 23 published amblyopia studies. Our analysis indicates that substantial numbers of patients over age 6 were successfully treated. Success rates under age 6 were not significantly better than those in older patients when the criterion for success was achievement of 20/30 acuity or better. When a criterion of 4 lines improvement was used, success rates at all ages under 16 were quite similar; in patients 16 and over, success by this criterion was significantly less frequent, but even in this group success was achieved by 42% of the patients.

Adolescent↗
PubMed1976

Adverse response to prism therapy in strabismus.

The recent literature on prism therapy in strabismus is reviewed. A case is reported in which an esotrope, treated by means of prism neutralization to effect sensory orthotropia, responded with a marked increase in the angle of squint. Guidelines are suggested to minimize risk of such adverse effect when prism therapy is attempted.

Child↗