22
JERALD J. BERNSTEIN
learned and emotional behavior and provides evidence for functional
homologies between the mammalian limbic system and parts of the forebrain of fish. These data are in support of Segaar’s hypothesis (1965) that
the function of the telencephalon is partially limbic in nature in reproductive behavior in fish.
In keeping with the findings that forebrainless fish conditioned to
light form unstable associations, Kholodov (1960) and Baru (1951, from
Karamyan, 1957) found that conditioning to sound or magnetic fields
was not affected by forebrain ablation whereas conditioned responses to
light were not stable. Crucian carp, ruff, shark, and ray were trained to
discriminate a light and a bell. Following removal of the telencephalon
animals required as many trials to learn the response as normal fish of the
same species. In lamprey, ganoids, and plagiostonies, this conditioned
response was unstable since animals did not respond one day after initial
acquisition of the task (Baru, 1951, from Karamyan, 1957).
Aronson and Herberman (1960) trained Tilapin to an operant task.
Animals were rewarded with food for striking a small Plexiglas target.
After subjects were trained to criterion, normal, sham-operated, and fish
with both olfactory bulbs ablated continued to respond with average
latency, Animals with complete forebrain ablation responded appropriately, but their average latency of response and variability in latency of
response increased considerably. Some animals with complete telencephalic ablation ceased responding after the seventh and eighth trial on
the first day postoperative.
The effect of telencephalic lesions on learning in paradise fish, Macropodus opercularis, was tested with a series of Umweg problems (mazes
of increasing complexity) and discrimination reversal tasks ( Warren,
1960, 1961). Telencephalic ablation was found to severely impair the
animals’ ability to perform in the maze. Normal paradise fish were compared with telencephalic ablated fish in their ability to learn a revcwal
task. Training was carried out in a T maze in which the targets presented
both brightness and positional cues. The fish were to select a black alley
on the right. After reaching criterion, the subjects were rcquircd to
reverse the discrimination habit and to go to the white alley on thc left.
It was found that forebrain ablated fish were inferior to controls in
learning a reversal task in the T maze (Warrcn, 1960, 1961).
In a continuous Y maze in w-hich goldfish were forced to turn consistently in a specified direction, it was found that forebrainless fish
learned the problem and its reversal better statistically than unopcrated
controls. However, in alternation learning (first the fish go right and thcn
go left), forebrainless fish did not perform as well as controls. However,
histological verification of the lesions was not available ( Inglc, 1965a,b).
JERALD J. BERNSTEIN
learned and emotional behavior and provides evidence for functional
homologies between the mammalian limbic system and parts of the forebrain of fish. These data are in support of Segaar’s hypothesis (1965) that
the function of the telencephalon is partially limbic in nature in reproductive behavior in fish.
In keeping with the findings that forebrainless fish conditioned to
light form unstable associations, Kholodov (1960) and Baru (1951, from
Karamyan, 1957) found that conditioning to sound or magnetic fields
was not affected by forebrain ablation whereas conditioned responses to
light were not stable. Crucian carp, ruff, shark, and ray were trained to
discriminate a light and a bell. Following removal of the telencephalon
animals required as many trials to learn the response as normal fish of the
same species. In lamprey, ganoids, and plagiostonies, this conditioned
response was unstable since animals did not respond one day after initial
acquisition of the task (Baru, 1951, from Karamyan, 1957).
Aronson and Herberman (1960) trained Tilapin to an operant task.
Animals were rewarded with food for striking a small Plexiglas target.
After subjects were trained to criterion, normal, sham-operated, and fish
with both olfactory bulbs ablated continued to respond with average
latency, Animals with complete forebrain ablation responded appropriately, but their average latency of response and variability in latency of
response increased considerably. Some animals with complete telencephalic ablation ceased responding after the seventh and eighth trial on
the first day postoperative.
The effect of telencephalic lesions on learning in paradise fish, Macropodus opercularis, was tested with a series of Umweg problems (mazes
of increasing complexity) and discrimination reversal tasks ( Warren,
1960, 1961). Telencephalic ablation was found to severely impair the
animals’ ability to perform in the maze. Normal paradise fish were compared with telencephalic ablated fish in their ability to learn a revcwal
task. Training was carried out in a T maze in which the targets presented
both brightness and positional cues. The fish were to select a black alley
on the right. After reaching criterion, the subjects were rcquircd to
reverse the discrimination habit and to go to the white alley on thc left.
It was found that forebrain ablated fish were inferior to controls in
learning a reversal task in the T maze (Warrcn, 1960, 1961).
In a continuous Y maze in w-hich goldfish were forced to turn consistently in a specified direction, it was found that forebrainless fish
learned the problem and its reversal better statistically than unopcrated
controls. However, in alternation learning (first the fish go right and thcn
go left), forebrainless fish did not perform as well as controls. However,
histological verification of the lesions was not available ( Inglc, 1965a,b).