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Biomedical subjects

R K Moore

Publications and source records attributed to R K Moore.

27 records · Page 2Linked to original sources
PubMed1982

Perception of suprathreshold stimuli during saccadic eye movements.

We have investigated the extent to which a graded series of suprathreshold stimuli are perceptually weakened by saccadic suppression. Stimuli were brief decrements of variable amplitude in the illumination of a Ganzfeld. For each of several decrements presented during fixation, we determined a matching amplitude of decrement presented during saccades. The measure of saccadic suppression was the ratio of these two amplitudes. The matches made by three observers exhibit ratios as high as 6:1 (0.8 log unit of suppression) near the threshold. Suppression decreases systematically as the strength of the stimulus increases, reaching 0.1 log unit or less for stimuli 2 log units above threshold.

Eye Movements↗
PubMed1982

Rapid ventilatory responses to changes in insufflated CO2 in awake roosters.

The ventilatory responses to pulses or steps in the fraction of CO2 in the insufflated gas stream (FICO2) in awake, unidirectionally ventilated White Leghorn roosters (Gallus domesticus) were studied. Within 0.2-0.5 s of the change in FICO2 at the syrinx, a change in inspiratory or expiratory flow occurred. Increases in FICO2 increased flow and tidal volume (VT), whereas decreases in FICO2 decreased flow and VT. Expiratory duration (TE) was markedly prolonged by decreases in FICO2 and shortened by increases. Inspiratory duration was affected little by FICO2 changes. The TE response to pulses of FICO2 (0.2-0.4 s duration) revealed a time dependency such that a maximum effect occurred when the pulses arrived at the syrinx at approximately midexpiration. The magnitudes of the responses were approximately proportional to the amplitude and duration of the FICO2 changes, but decreases in FICO2 had greater effects than increases. A likely receptor site for these responses is the intrapulmonary chemoreceptors, which appear to function in a reflex controlling airflow and timing of the ongoing breath.

Animals↗
PubMed1980

Eyeblinks and visual suppression.

A technique for bypassing the eyelids permits equivalent visual stimulation of the retina before, during, or after a blink. Sensitivity to these stimuli decreases during voluntary blinks. This indicates that the source of the deficit is neural rather than optical. Such a visual loss may help to explain the common experience that most blinks go unnoticed.

Brain↗