ISSN:
1432-1351
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary Light-dependent motor activity and phototactic behavior was investigated in 1) untreated, 2) blinded, and 3) blinded and pinealectomized eels (Anguilla anguilla L.). Neither blinding nor blinding combined with pinealectomy interfered with the observed nocturnal motor activity or the photonegative behavior characteristic for the untreated animals. However, an aluminum foil covering the skull of blinded animals altered the light-dependent motor activity pattern in contrast to blinded animals bearing a transparent plastic foil cover. Blinded animals with an aluminum foil covering the brain case exhibited a motor activity pattern resembling arrhythmicity. The motor activity pattern of 1) untreated, 2) blinded, as well as 3) blinded and pinealectomized eels followed an inversed light regime with a latency of about two days indicating that in the eel light is the dominatingZeitgeber triggering circadian motor activity patterns. The reported findings speak in favor of the existence of photosensitive areas in addition to the lateral eyes and the epiphysis cerebri. From the results of the covering experiments it is clear that these unknown photoreceptor sites must be located in the brain.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00605532
