The influence of cone adaptation upon rod mediated flicker

• Published in: Vision research (Oxford) Vol. 26; no. 8; pp. 1167 - 1176
• Main Authors: Frumkes, Thomas E., Naarendorp, Frank, Goldberg, Stuart H.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1986; Elsevier Science
• Subjects: Adaptation, Ocular; Biological and medical sciences; Cones; Dark Adaptation; Eye and associated structures. Visual pathways and centers. Vision; Flicker; Flicker Fusion - physiology; Fundamental and applied biological sciences. Psychology; Humans; Light; Male; Photoreceptor Cells - physiology; Psychophysics; Retina; Rod-cone interaction; Rods; Sensory Thresholds - physiology; Synaptic Transmission; Vertebrates: nervous system and sense organs; Retina; Rods; Rod-cone interaction; Cones; Psychophysics; Flicker; Human; Eye; Cone; Rod; Vision; Photoreceptor; Luminous stimulus; Sensory receptor; Adaptation; Threshold
• ISSN: 0042-6989; 1878-5646
• DOI: 10.1016/0042-6989(86)90098-2

The influence of annular fields on sensitivity to sinusoidal flicker was assessed in the dark adapted parafoveal retina. Test stimuli were 2°20′ in diameter; annuli had a 2°20′ inner and 7°30′ outer diameter. Rod flicker was studied with a “green” stimulus too dim to influence cones. Selective cone flicker was obtained using red and green flicker in counterphase and yoked together in modulation depth and scotopic illuminance. Results showed the following. (1) Annular stimulation of rods slightly facilitated rod-mediated flicker sensitivity to frequencies < 10 Hz. In contrast, annular stimulation of cones greatly facilitated rod-mediated sensitivity, particularly for flicker frequencies > 7 Hz. We designate this effect, cone-rod interaction. (2) Annular stimulation of cones has a negligible influence upon sensitivity to cone-mediated flicker frequencies < 15 Hz. In contrast, annular stimulation of rods has a large influence upon sensitivity to cone-mediated flicker, an effect we designate rod-cone interaction. (3) Within limits, both rod-cone and cone-rod interaction increase as the annular illuminance increases and as flicker. frequency increases; the limiting frequency and illuminance values, however, are different for the two forms of interaction. Results are compared with prior evidence that rod and cone signals summate to produce an absolute threshold or flicker sensation. We suggest that there are at least three mechanisms for interaction between rod- and cone-related signals.