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Biomedical subjects

E Francis

Publications and source records attributed to E Francis.

6 recordsLinked to original sources
PubMed1991

Snorting benzodiazepines.

Two cases of intranasal benzodiazepine use are presented. The methods of preparation and administration of the powder and accounts of the pharmacological effects of the drugs used are described. The pattern of development and progress of the habit and its associated features are delineated. Snorting benzodiazepines appears to be more common than is currently appreciated, and the clinical complications and implications of this habit are discussed.

Administration, Intranasal↗
PubMed1988

Anisotropies in global stereoscopic orientation discrimination.

Human orientation discrimination of long rectangular targets formed from dynamic random-element stereograms was assessed at four orientations (horizontal, vertical, left, and right oblique) as a function of width, disparity direction and magnitude using a temporal two-alternative, forced-choice paradigm. The results revealed the presence of an oblique effect in cyclopean orientation discrimination. In addition, observers discriminated targets with crossed disparity better than targets with uncrossed disparity, and had lower discrimination thresholds when the targets were oriented horizontally than vertically. These results demonstrate the existence of the oblique effect in the hypercyclopean domain comparable in magnitude to that present in the luminance domain.

Depth Perception↗
PubMed1987

The Ames window illusion: perception of illusory motion by human infants.

The sensitivity of human infants, 5 1/2-9 months of age, to the illusory oscillation of the Ames window was assessed in three experiments that employed some variant of the habituation-dishabituation and forced-choice preferential looking paradigms. In Experiment 1, three groups--5 1/2, 7 1/2, and 9 months of age--were given a visual choice between rotating rectangular and Ames windows after exposure to a rotating circular form. The two older groups preferred the Ames window. The results of Experiment 2 showed that this preference is not based on structural differences between the two windows. In Experiment 3, familiarization with an Ames window produced a preference for rotary motion while familiarization with a rectangular window produced a preference for oscillatory motion. These results suggest that sensitivity to the illusion emerges around 7 1/2 months of age, an outcome consistent with the emergence, at this time, of sensitivity to pictorial cues to depth.

Child Development↗