Electric Response of Visual Center in Fish, Especially to Colored Light Flash

The physiology of the teleostean optic tectum

“…Konishi (1960) confirmed the general finding, his results pointing to the longwave sensitivity of PSPI as compared with PSPn, which was more dependent on medium and short wavelengths under photopic conditions. In scotopic experiments, PSPI is still visible at very long wavelengths (670 nm), but there are problems in interpreting results like these, which are dependent on latency and on details of waveforms.…”

“…Daw also noted that the greensensitive channel in the surround was often associated with very delayed responses of the order of 400 ms. This reintroduces the idea of some kind of temporal coding of chromatic properties put forward by Konishi (1960). Spekreijse et al (1972) greatly expanded the number of known kinds of colour-coded RFs in the goldfish, describing some 12 types of configuration, from which they derived the following rules: (1) in a double-opponent receptive field, there is usually a red central channel, and this is usually ON; (2) a central green channel may be opponent to the red-sensitive channel, but it can be in parallel with it; (3) any particular colour-sensitive peripheral channel is opponent to a similar channel at the centre; (4) blue-sensitive centres are usually antagonistic to red; green is partly complementary to blue; (5) a field with a central blue channel has no peripheral channels.…”

“…The administration of single shocks to the optic nerve results in the appearance of compound, largely negative-going waves, which can be recorded by gross electrodes on the tectal surface (Buser, 19S5b;Konishi, 1960;Sutterlin and Prosser, 1970;Vanegas et al, 1974;Schmidt, 1979). Driving the electrodes down through the tectallayers results in characteristic changes in the form of the compound response; these can be ascribed to differing locations of the major synaptic sites, and are susceptible to sink!…”

“…Buser (1955a,b) published diagrammatic representations of the four major potential waves he observed in the catfish -PI and P2, and Tl and T2. Konishi (1960), working on the carp, illustrated oscilloscope records showing a brief initial wave PSPI, followed by a slower wave PSPn; Buser's P wave appears to correspond to PSPI and his Tl wave to PSPn ( Figure 9.9(a)). The smaller T2 wave is visible in some of Konishi's records (Figure 9.…”

Responses of the Optic Tectum to Telencephalic Stimulation in Catfish

“…The optic tectum in teleosts is laminated and has well-organized afferent inputs [Schroeder, 1974;Va negas, 1974aVa negas, , b, 1976Schroeder and Vanegas, 1977;Vanegas et al, 1984a], Among the major afferent sys tems, retinal input is well studied in respect to the evoked potentials and at the unitary level [Buser, 1955;Konishi, 1960;Prosser, 1965;Karamian et al, 1966;Sutterlin and Prosser, 1970;Vanegas et al, 1971Vanegas et al, , 1974Vanegas et al, , 1984bNiida and Sato, 1973;Vanegas, 1974a, b;O'Benar, 1976;Matsumoto and Bando, 1981;Bullock et al, 1990a, b]. Retinal axons from the contralateral eye enter and terminate in the external white layer, the stratum opticum (SO).…”