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Biomedical subjects

V Di Lollo

Publications and source records attributed to V Di Lollo.

At least 37 records · Page 2Linked to original sources
PubMed1986

Two-pulse temporal resolution in patients with glaucoma, suspected glaucoma, and in normal observers.

We examined the potential usefulness of a two-pulse temporal resolution technique in assessing early glaucomatous damage. Patients with glaucoma and suspected glaucoma and normal observers were studied. The technique produced a high sensitivity and specificity in separating glaucomatous from normal eyes and identified a subgroup of patients with suspected glaucoma for follow-up.

Differential Threshold↗
PubMed1985

Equating visibility of brief decrements: unconfounding duration and luminance.

A common procedure in visual psychophysics involves equating the visual effectiveness of brief luminous displays. It may be equally important to equate the effectiveness of brief interruptions, as when two displays are presented sequentially, separated by a variable interstimulus interval (ISI). For example, in a procedure devised by Phillips and Singer [Expl. Brain Res. 19, 493-506 (1974)], the first display consisted of a random pattern of dots and the second display consisted of the same pattern, but with one added dot. Detectability of the added dot was presumed to be determined by interactions of transient neural events produced at the beginning and end of the ISI. Lengthening the ISI was believed to weaken progressively the magnitude of the neural interactions, resulting in poorer performance. But lengthening the ISI also increased its visual effectiveness (darkness). Using ISIs equated in visual effectiveness for durations from 10 to 320 msec, we found that the visual effectiveness of the interval, not its duration, was the prime determinant of performance. This finding requires a reinterpretation of the neural mechanisms being studied in the Phillips and Singer task.

Female↗
PubMed1983

Temporal integration following intensification of long-lasting visual displays.

Duration of visible persistence is known to be inversely related to the duration of the inducing stimulus, within a critical interval estimated at between 100 and 150 msec. Stimuli longer than the critical interval yield little or no persistence. Six experiments investigated whether a brief period of intensification at the end of a stimulus longer than the critical interval could restore visible persistence. In the first experiment, a punctate stimulus ceased to give rise to visible persistence at exposure durations longer than the critical interval. The second experiment showed that persistence could be restored to a long display by briefly intensifying the component dots just before the end of the display. The remaining four experiments explored the limits and the distinguishing characteristics of this effect. Two alternative explanations of the results are described and evaluated.

Adaptation, Ocular↗
PubMed1977

Effects of gap size between shaft and fins and of angle of fins on the Müller--Lyer illusion.

Assimilation theory was employed to generate quantitative predictions relating the ingoing Müller--Lyer illusion to both angle of fin and gap between shaft and fin. Gap sizes were varied from zero to 18 mm in steps of 2 mm, and angles of fins were varied from 30 degrees to 180 degrees in steps of 30 degrees. Five subjects adjusted the length of a comparison line to match the apparent length of the shaft at each combination of gap size and angle of fin. It was predicted that the gap necessary for a reversed illusion to occur, and the gap at which the maximal reversed effect occurred, would be inversely related to angle of fins. Empirical functions verified the predictions.

Humans↗