PubMed Health⌕ Search

Biomedical subjects

E Tobach

Publications and source records attributed to E Tobach.

At least 19 recordsLinked to original sources
PubMed1997

Viewing of self and nonself images in a group of captive orangutans (Pongo pygmaeus Abellii).

Reports on self-recognition in great apes have been mostly derived from experimental studies of mirror behavior (mark test) requiring anesthetization of the animals. We investigated a relatively noninvasive technique to study this behavior. In two experiments with a group of captive orangutans (1 adult male, 3 adult females, 1 juvenile male, and 1 juvenile female), we presented combinations of blank posters, life-size portraits of each individual in the group, a mirror, and videos. Durations of viewing and patterns of viewing were recorded. The prominent features of the viewing were the differences among the individuals in frequency, duration, and pattern of viewing. Some evidence of mirror-based self-referent behavior (behavior in which the activity of the animal with its body was related to the activity of the image in the mirror) was seen in the juvenile female, but more was seen in one adult female. This adult female spent the most time viewing the mirror and was the only animal to view her own portrait more than the other portraits in one session. In addition, she moved from one portrait to another, and back to the first, and to her own portrait and the mirror in a pattern resembling comparison of the two portraits as well as of her portrait and her mirror image. It is suggested that data based on self-referent behavior of the same animal during self-viewing in a mirror and during viewing of its self-portrait and on behavior observed in the mark test are worth further investigation.

Animals↗
PubMed1996

Sex and gender.

Explore the source record for details and available documents.

Female↗
PubMed1992

Distance perception in the spiny mouse Acomys cahirinus: vertical jumping.

Acomys cahirinus, a precocial muroid, that has shown precise jumping in the natural habitat, did not jump from 25 cm in a laboratory situation. To investigate this further, A. cahirinus were observed jumping from platforms at two different heights, onto different sized checkered substrates and from a visual cliff. Adult animals discriminated between platforms that were 6.4 cm and 25.4 cm above the substrate and between small and large checkered patterns on the floor. Most adult animals and neonates jumped down on the shallow side of the visual cliff. Animals developed individual patterns of jumping over a series of trials, with some jumping often, some rarely, and others jumping only from the low platform. Good distance perception was indicated when they did not jump from heights, and by their making appropriate postural adjustment when they did jump from heights and landed without mishap. Different spacing of trials indicated that height was a more effective stimulus for animals which had all four conditions on the same day, while floor pattern was more effective for animals with each of the four conditions on a separate day.

Adult↗
PubMed1988

Two-way shuttlebox avoidance conditioning in three DAB rat stocks.

Avoidance conditioning in FH rats, characterized by a peripheral serotonin deficiency, was compared with that in two stocks presumed to be their ancestors, Long-Evans (LE) and Wistars (W). Escapes, conditional avoidance response (CAR), and activity (locomotion) of the animals were studied in a two-way shuttlebox. FH females made fewer escapes and more CAR's, and were more active than both LE and W females. The behavioral differences among the males of the three stocks were not statistically significant. A CNS serotonin deficiency may be involved in the conditioning and activity differences among the females of the three stocks. Possible variation between sexes should be considered in investigating levels of CNS serotonin in FH rats, as well as other stocks.

Animals↗
PubMed1985

Multiple [3H]imipramine binding sites in brains of male and female Fawn-Hooded and Long-Evans rats.

Comparisons of high- and low-affinity [3H]imipramine binding to whole brain homogenates from adult male and female rats of the Fawn-Hooded and Long-Evans strains were performed. Most strikingly, no significant differences were observed between the two strains in any of the binding parameters, indicating that brain [3H]imipramine binding sites, which may be related to the serotonergic uptake process, appear normal in a strain of rats with serotonin platelet storage pool disease. However, a significant sex difference in high- but not low-affinity whole brain [3H]imipramine Bmax values was observed, with females of both strains having higher densities than males. The observed sex difference in densities of high-affinity [3H]imipramine binding sites necessitates further research into possible sex hormone interactions with this binding site and serotonergic transmitter systems.

Animals↗
PubMed1975

Olfactory bulbectomy and nursing behavior in rat pups (Wistar DAB).

To determine whether bilateral olfactory bulbectomy led to a change in nursing behavior, and thus death, we bilaterally bulbectomized (BX) pups from 14 litters at 2, 7, and 11 days of age. Litters treated on Days 2 and 7 consisted of 3 BX pups, 2 surgical control (SC) pups, and 2 handling control (HC) pups. Litters treated on Day 11 consisted of 1 or 2 BX, 1 or 2 incompletely bulbectomized pups (IBX), 2 SC pups, and 2 HC pups. These litters and 3 additional nontreated litters were observed on Days 4,7,10,13, and 16. A smaller number of BX pups survived through Day 10 than SC, HC, IBX, and nontreated pups. Differential treatment of the BX pups by females or littermates was not found. The females' mammary glands were functional but the BX pup stomachs had little or no milk. The BX pups spent less time nursing and more time away from the female and their littermates than did the other pups.

Animals↗