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S Coren

Publications and source records attributed to S Coren.

At least 91 records · Page 5Linked to original sources
PubMed1980

Family patterns in four dimensions of lateral preference.

Hand, eye, foot, and ear preference were examined in a sample of 459 biologically related parent-offspring triads and 434 sibling pairs. Intercorrelations were computed using the side of preference as the dependent variables and then again using the absolute strength of the displayed preference irrespective of side. The directional analyses did not show strong patterns of familial similarities; however, relatives did tend to resemble each other in the degree of lateralization manifested. Maternal and paternal resemblance to offspring vary over the four indices of laterality, and there are some suggestions of sex-specific interactions. These results imply that genetic influence may operate to affect the degree of expressed preference, while the side of preference may not be genetically encoded. These findings also suggest that lateral preferences for limb and sense organ may not be due to a single causal mechanism.

Ear↗
PubMed1980

Birth factors and laterality: effects of birth order, parental age, and birth stress on four indices of lateral preference.

As an alternative to genetic theories of handedness, some theorists have offered an environmental mechanism, associated with birth stress, for the appearance of left-handedness. They suggest that brain damage as a result of birth difficulties can lead to a switch in hand preference from the right side to the left side. Consequently, one should find more left-handers in groups where the probability of the occurrence of birth stress is greater. Three studies are presented which explore the laterality of not only hand but also foot, eye, and ear, in a total of 5161 individuals, in an attempt to assess any relationship to birth stress. Maternal age seems to predict deviations from dextrality, dependent on the sex of the offspring, while paternal age and birth order do not. The use of a direct measure of conditions predisposing toward birth stress suggests that these results depend on prenatal or perinatal environmental trauma rather than chromosomal factors.

Adolescent↗
PubMed1980

Life-span age trends in laterality.

Laterality of hand, foot, eye, and ear was measured in a sample of 1964 subjects, ranging in age from 8 to 100 years. Age trends were found, with hand, foot, and eye preference becoming more right-sided and ear preference becoming more left-sided with increasing age. Sex differences emerged in foot, eye, and ear preference but these did not systematically interact with the age variable. Several causal mechanisms are proposed but none can fully explain either the direction or the magnitude of the observed age changes. Thus, these data are most consistent with the view that the study of sidedness in humans should proceed with a consideration of a complex of underlying factors and individual difference variables.

Adolescent↗
PubMed1979

Normative data on hand position during writing.

It has been suggested that inverted versus upright handwriting position is an indicator of cerebral lateralization and the pattern of neuromotor control. Normative data on the prevalence of these handwriting positions was collected from 1758 subjects ranging in age from 10 to 75 years. Both age and sex differences in the prevalence of inverted handwriting positions were found.

Adolescent↗
PubMed1979

Levels of processing in visual illusions: the combination and interaction of distortion-producing mechanisms.

In order to assess the mode and sequence of interaction of visual-geometric illusion mechanisms, responses to simple and composite overestimation configurations were measured in 72 observers. Analysis suggests that some illusion mechanisms add their distortions to the outputs of others and that other mechanisms average. A logarithmic or near-logarithmic transformation seems to occur when illusory effects combine. A path analysis of the results suggests that some illusory mechanisms combine in a serial manner and that others operate on separate parallel channels. Notions based on simple addition of illusory effects and on serial linear processing are not supported by these analyses.

Discrimination Learning↗
PubMed1979

Heritability in visual-geometric illusions: a family study.

The Müller-Lyer and Ebbinghaus illusions were tested in 203 mother-father-offspring triads and 303 sibling pairs. Significant familial resemblances were found in all but the overestimated segment of the Ebbinghaus illusion. These results suggest that responses to visual-geometric illusions, mediated by optical or neural interactive mechanisms, show patterns of familial resemblance which may be based upon heritable factors.

Family↗
PubMed1979

Visual-geometric illusions: unisex phenomena.

The possibility of sex differences in responses to visual-geometric illusions was investigated with the use of forty-five illusion variants and a sample of 221 observers. No difference in illusion magnitude as a function of sex was found. A second experiment measured illusion decrement and transfer of decrement to other illusion configurations. Again there were no significant differences between male and female observers.

Female↗
PubMed1978

Iris pigmentation and visual-geometric illusions.

Blur or degrading of the retinal image has been shown to be a factor in the formation of visual-geometric illusions where intersecting line elements are present. Light irises allow more scattered light within the eye, which results in more image degradation than found in dark-eyed subjects. Measurements on 755 observers show that illusion magnitude varies as a function of iris pigmentation for a configuration with intersecting line elements (Müller-Lyer illusion), but not for a configuration devoid of such features (Ebbinghaus illusion).

Eye Color↗
PubMed1978

Sighting dominance and binocular rivalry.

Two experiments are reported that attempt to explore systematically the role of sighting dominance during binocular rivalry. Experiment 1 showed that the sighting eye tends to display longer total viewing time, and experiment 2 indicated that this asymmetry remained even when observers had increased experience with rivalrous stimulation. Additional analysis revealed that the average dominance period of the sighting eye was longer than that of the nonsighting eye, resulting in significant sequencing effects during the rivalry process.

Depth Perception↗
PubMed1977

Fifty centuries of right-handedness: the historical record.

A survey of more than 5000 years of art work, encompassing 1180 scorable instances of unimanual tool or weapon usage, revealed no systematic trends in hand usage. The right hand was used in an average of 93 percent of the cases, regardless of which historical era or geographic region was assessed.

Art↗
PubMed1977

Neural interactions and subjective contours.

Increment thresholds were measured on either side of the locus of subjective contours and inequivalent loci for control figures. The data indicate a small change in increment threshold value in the direction predicted by theories postulating neural interactive components in the formation of subjective contours.

Differential Threshold↗
PubMed1977

The case for misapplied constancy scaling: depth associations elicited by illusion configurations.

It has been suggested that many visual-geometric illusions arise from inappropriate evocation of size-constancy by depth cues implicit in illusion configurations. Observers gave free association responses while viewing illusion figures. Analysis of these responses provides weak but consistent evidence for the elicitation of depth in the Sander parallelogram, Mueller-Lyer, Zoellner, and Ehrenfels variant of the Ponzo illusion. No evidence for depth is found in the normal form of the Ponzo, Poggendorff, and horizontal-vertical illusions, and the evidence is ambiguous in the Orbison configurations. These results indicate that depth processing may be evoked by some, but not all, classical illusion forms.

Cues↗
PubMed1976

The dominant eye.

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Dominance, Cerebral↗