PubMed Health⌕ Search

Biomedical subjects

M Domjan

Publications and source records attributed to M Domjan.

At least 37 records · Page 2Linked to original sources
PubMed1991

Discriminating the sex of conspecifics by male Japanese quail (Coturnix coturnix japonica).

How male Japanese quail (Coturnix coturnix japonica) discriminate the sex of conspecifics at a distance was investigated by testing subjects with male and female stimulus birds on the other side of a small window after opportunities to copulate with females and again after repeated exposures to males in the absence of copulatory opportunity. Time spent near the window, frequency of window approaches, duration of window visits, rate of walking near the window, line crossings outside the window area, pecking the window, and crowing were measured. Subjects responded similarly in the presence of male and female stimulus birds during the first test block but discriminated the sex of conspecifics after noncopulatory exposures to males. The discrimination was evident in less locomotion and less crowing in the presence of females as compared with males and, as predicted by a discrimination learning hypothesis, developed largely through a change in responding to males.

Animals↗
PubMed1989

Sexual-discrimination learning in male Japanese quail (Coturnix coturnix japonica).

We investigated how male Japanese quail (Coturnix coturnix japonica) learn through extensive social and sexual experience to discriminate between male and female conspecifics. Opportunity for heterosexual copulation was important for this learning, but even extensive copulatory opportunity was not sufficient to produce a sexual discrimination; subjects also required exposure to other males. Exposure to females after copulatory opportunity did not produce a sexual discrimination but facilitated its acquisition. Time or exposure to only the visual features of male birds (provided by taxidermic models) after copulatory opportunity did not result in differential responding to male and female conspecifics. Finally, presenting stimulus birds one at a time proved to be a more sensitive test of sexual-discrimination learning than presenting two stimulus birds at the same time. The results indicate that sexual-discrimination learning is similar to conventional associative learning.

Animals↗
PubMed1989

Contextual conditioning and the control of copulatory behavior by species-specific sign stimuli in male Japanese quail.

Three experiments were conducted to identify species-specific sign stimuli sufficient to elicit copulatory behavior in male Japanese quail and to determine how learning is involved in the control of behavior by these sign stimuli. In Experiment 1, sexually experienced subjects were tested for copulatory behavior with a live female quail and with a model consisting of a female quail's head and neck mounted in front of a foam pad. Comparable levels of copulatory behavior were observed in the two tests, indicating that static visual cues provided by a female quail's head and neck are sufficient to elicit copulatory behavior in this species. Experiment 2 showed that male birds that previously received numerous opportunities to copulate with a live female quail in the test situation were significantly more likely to copulate with the head + neck model than were sexually inexperienced subjects. Experiment 3 showed that prior sexual experience with live quail facilitated responding to the head + neck model only if the sexual experience was provided in the same place where subjects were later tested with the model. This last finding suggests that sexual experience facilitates control of copulatory behavior by species-specific sign stimuli through contextual conditioning. Contextual conditioning may lower the threshold for sexual behavior with the result that a stimulus as impoverished as an immobile model containing only the head and neck of a female quail becomes sufficient to elicit normal levels of copulatory behavior. The results are also discussed as an example of conditioned stimulus facilitation of responding to an unconditioned stimulus.

Animals↗
PubMed1988

Conditioning of appetitive and consummatory sexual behavior in male Japanese quail.

Two different types of stimulus objects, a live female quail artificially adorned with bright orange feathers and an inanimate toy dog, served as conditioned stimuli. For subjects in experimental groups, the conditioned stimuli were presented shortly before access to a sexually receptive normal female quail. For subjects in control groups, exposure to the conditioned stimuli was unpaired with copulatory opportunity. Subjects in the experimental but not in the control groups quickly came to approach the location of the conditioned stimulus objects. When an adorned female quail served as the conditioned stimulus, the conditioned approach behavior was controlled by a combination of the presence of the orange adornments and the visual cues of the head and neck of the female bird, and the approach behavior persisted as the adorned female moved to new locations. When the toy dog served as the conditioned stimulus, the conditioned approach behavior was limited to the spatial cues that surrounded the toy dog during conditioning trials. Although both types of stimulus objects evoked conditioned approach behavior, only the adorned female stimulus supported copulatory behavior. This last finding indicates that copulatory behavior can become redirected toward novel stimuli as a result of conditioning, but only under special circumstances. The results are consistent with the suggestion that appetitive components of reproductive behavior are more susceptible to conditioning than consummatory components. Possible reasons for this are discussed, together with implications of the results for the contribution of conditioning processes to sexual selection.

Animals↗
PubMed1987

Photoperiodic and endocrine control of social proximity behavior in male Japanese quail (Coturnix coturnix japonica).

Previous research had shown that reproductively mature male Japanese quail maintained on a 16:08 light/dark (16L:8D) photoperiod spend about 75% of their time throughout daylight hours near a window that provides visual access to a female conspecific. In contrast, females do not display a corresponding tendency to remain near male conspecifics. In Experiment 1, I demonstrated that the social proximity behavior of male Japanese quail declines significantly when photostimulation is restricted to 2 hr daily (02:22 light dark; 2L:22D), but can be restored by reinstituting the 16L:8D schedule. Changes in the photoperiod produced corresponding changes in the size of the cloacal gland, and androgen-dependent organ. The low levels of social proximity behavior and cloacal gland size of males maintained on short daily exposures to light (2L:22D) also could be reversed by sc implants of testosterone (Experiment 2), and this recovery was to some extent sensitive to testosterone dose (Experiment 3). The present studies indicate that social proximity behavior in male Japanese quail is androgen dependent and provide a behavioral assay for neurohormonal studies of sexual behavior that does not depend on brief phasic responses.

Animals↗
PubMed1986

Determinants of social proximity in Japanese quail (Coturnix coturnix japonica): male behavior.

Following opportunity to copulate with a female housed in an adjacent compartment, male Japanese quail spent 64% of their time near a window that provided visual access to the female (Experiment 1). This social proximity behavior persisted for at least 2 weeks of continual exposure to the window despite lack of further physical access to the female (Experiment 2) and was evident at all daylight hours (Experiment 3). Female Japanese quail stimulated more proximity behavior in male conspecifics than did other male Japanese quail or birds of other species (Experiments 4 and 5). However, many characteristics of the female quail were not critical. The female quail did not have to be previous sexual partners, familiar, sexually experienced, or reproductively competent to stimulate proximity behavior in males (Experiments 4 and 5). Experiment 6 demonstrated that the social proximity behavior was primarily a response to the visual aspects of the females. The results are discussed in relation to mate-guarding and surveillance behavior, and implications of the data for sexual classical conditioning of male Japanese quail are noted.

Animals↗
PubMed1986

Sexual Pavlovian conditioned approach behavior in male Japanese quail (Coturnix coturnix japonica).

A localized visual stimulus presented immediately prior to access to a female conspecific stimulated approach behavior in male Japanese quail after several conditioning trials. Development of this conditioned approach behavior was observed with two different types of signal lights, 10-s and 30-s signal durations, large and small experimental chambers, and with male birds housed continually in the conditioning chambers or only placed in the chamber for brief daily sessions. Conditioning also resulted in shorter latencies to initiate copulation in males given access to a female following the signal light, in comparison with males that received access to a female unannounced by the light. Although some aspects of the conditioning experience were retained over a 6-week interval, some loss of the behavior was also observed. The conditioned behavior also decreased with repeated extinction trials, during which the signal light was presented in the absence of access to a female conspecific. The results are discussed in relation to other aspects of the social behavior of Japanese quail and other studies of sexual conditioning.

Animals↗
PubMed1982

Selective associations in one-day-old rats: taste-toxicosis and texture-shock aversion learning.

One-day-old rats learned aversions to a novel taste paired with lithium-induced distress and to a tactile stimulus paired with brief electric shocks. However, aversions did not develop when taste was paired with shock or when the tactile stimulus was paired with lithium treatment. The aversions occurred only when lithium treatment immediately followed taste exposure and when shock was concurrent with exposure to the tactile stimulus. These findings indicate that selective associations in aversion learning are mediated by innate mechanisms that govern conditioning in the absence of extensive ontogenetic experience. The present research also shows that selective associations are sufficient for the occurrence of long-delay learning.

Animals↗
PubMed1982

Note on aversion learning to the shape of food by monkeys.

Vervet and grivet monkeys were repeatedly tested eating bar- and circle-shaped cookies. One subject was always injected with lithium immediately after eating cookies with the circle shape and learned to avoid the circular cookies while continuing to eat the bar-shaped cookies. Another subject received similar treatment except that lithium injections were always delayed 30 minutes after access to the circle-shaped cookies. She also acquired a discriminative aversion. Aversion learning was not observed with 60-minute delayed toxicosis or with lithium injections administered unpaired with access to the cookies. The two types of cookies differed only in shape, and conditioning and test sessions were conducted in total darkness to preclude the use of visual cues. Therefore, the avoidance observed in subjects conditioned with immediate and 30-minute delayed toxicosis represents a conditioned aversion to the shape of the cookies as revealed by tactile cues. These findings illustrate that monkeys can learn to select food on the basis of tactile stimuli when such stimuli are conditioned with delayed aversive stimulation.

Journal Article↗
PubMed1980

Increased drinking stimulated by exposure to lithium-conditioned taste cues: effects of conditioning trials and drug dose.

Rats first received differential conditioning in which the oral infusion of one flavored solution (the CS+) was followed by lithium injection and the oral infusion of a different solution (the CS-) was followed by no drug treatment. The intake of a novel palatable flavor was then measured after infusion exposure to either the lithium-conditioned CS+, the taste of tap water, or the CS-. Exposure to the CS+ stimulated more drinking than comparable exposure to tap water following 2-8 differential conditioning trials (Experiment 1), following conditioning with lithium doses of 0.75-3.0 mEq/kg (Experiment 2), and in comparison with both exposure to water and exposure to the CS- (Experiment 3). However, the phenomenon was not closely related to the degree of aversion subjects acquired to the lithium-paired taste solution. These results indicate that a complete characterization of the changes in drinking which are elicited by lithium-conditioned stimuli requires recognition of not only the suppression of intake commonly observed in the presence of the conditioned stimuli, but also the enhancement of intake evident as an after-effect of the lithium-conditioned stimuli.

Animals↗
PubMed1980

Aversion learning in 5-day-old rats: taste-toxicosis and texture-shock associations.

Five-day-old rats that received a single pairing of a novel saccharin flavor with lithium treatment learned to suppress ingestion of saccharin on subsequent occasions (Experiment 1). This flavor aversion learning was inversely related to the interval between the novel flavor experience and drug administraton, wit h significant aversions being learned with intervals of 0 and 30 min but not with intervals of 60 and 90 min (experiment 2). The conditioning was observed when hypertonic lithium served as the unconditioned stimulus but did not occur with isotonic lithium or hypertonic saline injections (Experiment 3). These results indicate that flavor aversion learning in infant rats is a result of the joint action of two factors--pure drug effects and the somatic pain and irritation produced by the tonicity of the injected agent. The taste aversion learning was specific to the drug-paired flavor, and evidence was presented suggesting that 5-day-old rats display a natural hesitancy to consume novel edibles (neophobia) (Experiment 4). Experiment 5 demonstrated that 5-day-old rats selectively associate tactile stimuli with shock but not with the gastrointestinal consequences of lithium. Implications of the mechanisms involved in flavor aversion learning in infant rats are discussed as they relate to adaptation and food selection in adult animals.

Animals↗
PubMed1980

Aftereffects of lithium-conditioned stimuli on consummatory behavior in the presence or absence of the drug.

Drinking is increased by prior exposure to lithium-conditioned stimuli. Experiment 1 showed that this phenomenon is not an artifact of testing subjects with a novel, palatable drinking fluid and also showed that lithium-conditioned olfactory stimuli produce a biphasic change in drinking, with drinking suppressed at the start of exposure to the conditioned stimulus (CS) and enhanced a long time after CS onset or exposure. Experiment 2 showed that the increased drinking aftereffect of lithium-conditioned stimuli is not a result of the instrumental reinforcement of the drinking response by the scheduling of water access following drug injections during conditioning, and Experiments 3, 4, and 5 showed that the increased drinking effect occurs even if subjects are injected with lithium prior to the test session. The results of Experiments 3 and 5 alos showed that lithium administration and exposure to lithium-conditioned stimuli have independent and opposite aftereffects: Lithium disrupts drinking, whereas prior exposure to lithium-conditioned stimuli increases consumption. The relevance of conditioned opponent and compensatory processes to the findings is discussed.

Animals↗
PubMed1979

Effects of distribution of the drug unconditioned stimulus on taste-aversion learning.

Rats injected with lithium chloride after exposure to a taste or olfactory stimulus learn stronger aversions to these cues if the drug is administered in two small injections 35 min apart than if all of the drug is given in a single injection. This facilitation of conditioning produced by distribution of the drug unconditioned stimulus occurs with both low and high lithium doses (Experiments 1 and 2), is more evident in male than in female rats (Experiment 1), and is directly related to the amount of the flavored solution consumed prior to drug treatment (Experiment 4). Increasing the interval between two small drug injections beyond an optimal value results in a progressive loss of the facilitation of conditioning (Experiments 2 and 3), and the optimal drug distribution interval may be shorter for olfactory cues (Experiment 3) than for taste stimuli (Experiments 1 and 2). Control observations (Experiments 5A and 5B) showed that the drug distribution effect is not due to handling or other non-drug factors involved in giving two rather than only one injection. The phenomenon is consistent with recently-proposed models of conditioning and suggests that the differential effectiveness of various drugs in taste aversion conditioning may be related to differences in the time course of the unconditioned drug effects.

Animals↗