ANALYSIS OF OSCILLATIONS OF THE VISUAL SENSITIVITY

Citation
F. Thoss et al., ANALYSIS OF OSCILLATIONS OF THE VISUAL SENSITIVITY, Vision research, 38(1), 1998, pp. 139-142
Citations number
9
Categorie Soggetti
Neurosciences,Ophthalmology
Journal title
ISSN journal
00426989
Volume
38
Issue
1
Year of publication
1998
Pages
139 - 142
Database
ISI
SICI code
0042-6989(1998)38:1<139:AOOOTV>2.0.ZU;2-4
Abstract
At the subjective threshold, repeated flash test stimuli are perceived by the observer on only 50% of occasions, since the detectability of a single light stimulus fluctuates with time. For the analysis of thes e fluctuations we have recorded sequences of positive (''seen'') and n egative (''not seen'') responses, stimulating at 10 sec intervals for 50 min. These records, reflecting the time course of detectability, sh ow periodic fluctuations. The frequencies of these fluctuations have b een estimated by autocorrelation and Fourier analysis of the records. For 19 subjects they yielded spectra with preferential period duration s between 0.5 and 2, respectively 5 and 15 min in 15 cases, and some s pectra are noisy. (C) 1997 Elsevier Science Ltd.