PubMed Health⌕ Search

Biomedical subjects

E Matin

Publications and source records attributed to E Matin.

17 recordsLinked to original sources
PubMed1993

Saccadic overhead: information-processing time with and without saccades.

Information-processing time was compared for serial and spatially distributed visual presentations with performance measures that permit the separation of total time into its during-display and post-display components. For all subjects, there was a significant saccadic overhead, that is, less time was required with the serial format, which allowed data access without eye movements. However, the magnitude of the overhead decreased as task complexity increased. All subjects were able to exercise some control over the distribution of total processing time, trading off short during-display times with longer post-display times and vice versa.

Adult↗
PubMed1990

An adaptive (tracking) procedure for measuring visual search.

PEST, an adaptive (tracking) procedure originally developed for sensory research, was modified for cognitive studies with the multiple sequential frames paradigm and a letter-search task. The program which controlled stimulus presentation was designed to track the frame duration required for successful search on 75% of trials (the duration threshold). For each of the three subjects used, the threshold increased as a linear function of the number of sequentially presented frames, which varied between 1 and 10. Each tracking run was immediately followed by 40 trials with frame-exposure time fixed at the computer-selected threshold. Performance on these fixed level trials was close to the expected 75% correct. The Discussion addresses issues related to the use of the threshold measure in basic and applied cognitive research, explores the present findings about performance on fixed level trials at the computer-selected threshold, and examines the increase in duration threshold with the number of sequentially presented frames.

Adult↗
PubMed1984

Effects of intertrial interval, orientation, and adaptation on orientation discrimination measured with a yes-no signal detection paradigm.

Orientation discriminations were measured with a 3.8-cpd sinusoidal grating stimulus and a yes-no signal-detection procedure. Analysis showed that such discriminations are independent of light-adaptation conditions and of intertrial interval over the 2- to 8-sec. range of values explored. However, they are strongly influenced by the orientation where measurements are made (the "oblique effect").

Adaptation, Ocular↗
PubMed1972

Metacontrast and saccadic suppression.

A vertical slit of light illuminated during horizontal saccadic eye movements appeared as a horizontally extended smear when stimulation was terminated before the saccade ended. However, on trials for which duration of illumination of the slit was extended into the period after the saccade, the smear appeared shorter and dimmer, and a clear image of the slit was seen. With further increases in duration, no smears were seen at the highest luminance of the slit employed, although smears were more than 2 log units above threshold when flashes were brief. This saccadic suppression is discussed in terms of metacontrast, with the accumulated luminance in the period after the saccade primarily responsible for masking the effects of the stimulation received during the movement of the eye.

Eye Movements↗