PMID- 2059568
OWN - NLM
STAT- MEDLINE
DCOM- 19910805
LR  - 20190912
IS  - 0952-5238 (Print)
IS  - 0952-5238 (Linking)
VI  - 6
IP  - 4
DP  - 1991 Apr
TI  - Light-adaptation properties of the ultraviolet-sensitive cone mechanism in 
      comparison to the other receptor mechanisms of goldfish.
PG  - 293-301
AB  - The light-adaptation properties of goldfish photoreceptor mechanisms were 
      examined using Stiles' two-color threshold technique. Threshold vs. background 
      intensity (TVI) curves were determined for isolated cone and rod mechanisms using 
      the heart-rate conditioning technique. The principal aim of this study was to 
      compare the light-adaptation properties of the ultraviolet (UV)-sensitive cone 
      mechanism to the other receptor mechanisms of goldfish. This examination revealed 
      several striking functional differences: (1) The UV-sensitive cone mechanism 
      threshold vs. background intensity (TVI) exhibited a slope of 0.65 (compared to 
      the approximate 1.0 for the other cone mechanisms on a log/log plot) and thus was 
      not in accordance with Weber's law. This may in part be related to the intrusion 
      of the blue-sensitive mechanism at the upper radiance range. (2) The operation of 
      the UV-sensitive cone mechanism was limited to intermediate intensities (i.e. not 
      very dim or bright). (3) The UV-sensitive cone mechanism exhibited a Weber 
      fraction or luminance contrast threshold of 0.316 that was approximately six 
      times larger than the other cone mechanisms but comparable to the rod mechanism. 
      This indicates that the UV-sensitive cone mechanism performs relatively poorly in 
      terms of brightness contrast detection.
FAU - Hawryshyn, C W
AU  - Hawryshyn CW
AD  - Department of Biology, University of Victoria, British Columbia, Canada.
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Vis Neurosci
JT  - Visual neuroscience
JID - 8809466
SB  - IM
MH  - Adaptation, Ocular/*physiology
MH  - Animals
MH  - Goldfish
MH  - Light
MH  - Photoreceptor Cells/*physiology
MH  - Sensory Thresholds
MH  - *Ultraviolet Rays
MH  - Vision Tests
EDAT- 1991/04/01 00:00
MHDA- 1991/04/01 00:01
CRDT- 1991/04/01 00:00
PHST- 1991/04/01 00:00 [pubmed]
PHST- 1991/04/01 00:01 [medline]
PHST- 1991/04/01 00:00 [entrez]
AID - S0952523800006544 [pii]
AID - 10.1017/s0952523800006544 [doi]
PST - ppublish
SO  - Vis Neurosci. 1991 Apr;6(4):293-301. doi: 10.1017/s0952523800006544.