Conspecific Images as Elements of Compound Stimuli Controlling Operant Responding in Female Rhesus Monkeys

Six adult female rhesus monkeys (Macaca mulatta) performed food-reinforced button presses in a compound stimulus discrimination paradigm. Three subjects were trained on a compound stimulus consisting of a color motion picture of an adult male rhesus superimposed over a homogeneous blue field of color. A second group of three subjects was trained on a compound consisting of a color slide depicting an adult male rhesus and the blue field. Subsequent testing of relative stimulus control exerted by either compounds, conspecific stimuli (movie-slide) or blue field alone was carried out. Results indicated that for the movie group, stimulus control was attenuated when either the conspecific stimulus or blue field was presented as a single S+ stimulus compared to tests using the compound stimulus as S+. Subjects in the movie group shared attention to both constituent elements of the compound. Statistically significant differences in stimulus control between compound, conspecific stimulus, and blue field were not found for the slide group. Superior control by the compound movie-blue field was explained as the result of increased visual salience of an altered (blue) conspecific image.

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Effects of Prenatal Cocaine Exposure on Brain Dopamine Receptor Function, Behavior, and Cocaine Reinforcement in Adult Male and Female Rhesus Monkeys

PsycEXTRA Dataset ◽

10.1037/e654422011-001 ◽

2011 ◽

Author(s):

Michael A. Nader

Keyword(s):

Dopamine Receptor ◽

Adult Male ◽

Rhesus Monkeys ◽

Receptor Function ◽

Cocaine Exposure ◽

Brain Dopamine ◽

Prenatal Cocaine Exposure ◽

Male And Female ◽

Prenatal Cocaine ◽

Female Rhesus

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Pituitary response to LRH and TRH stimulation and peripheral steroid hormones in conscious and anaesthetized adult male rhesus monkeys (Macaca mulatta)

Acta Endocrinologica ◽

10.1530/acta.0.0930287 ◽

1980 ◽

Vol 93 (3) ◽

pp. 287-293 ◽

Cited By ~ 16

Author(s):

E. Jean Wickings ◽

E. Nieschlag

Keyword(s):

Adult Male ◽

Rhesus Monkeys ◽

Serum Testosterone ◽

Fold Increase ◽

Serum Cortisol ◽

Serum Levels ◽

Biologically Active ◽

Similar Response ◽

Response Curves ◽

Male Rhesus

Abstract. Adult male rhesus monkeys are aggressive animals and very difficult to handle. Hence experimental manipulations necessarily involve the use of restraint procedures, either chemical or physical, which may influence endocrine functions. Therefore, the effects of ketamine anaesthesia on basal hormone levels and on the pituitary response to LRH and TRH were investigated in 4 adult male rhesus monkeys. Values were compared to those obtained from the same animals restrained in primate chairs for approximately 48 h, a procedure to which they had been accustomed to over the preceding 6 months. Serum cortisol levels under anaesthesia were at all times lower than in conscious monkeys, but increased after 2 h to values twice as high as measured initially. Serum testosterone concentrations were not significantly different on the two occasions, but levels under anaesthesia were slightly higher initially than in the conscious monkeys, and decreased gradually over the 3 h test period. Initial prolactin levels were lower in the anaesthetized monkeys, and increased 2–3-fold after 90 min; values at 3 h were not significantly different from those in conscious monkeys. Intravenous TRH elicited a similar response in prolactin on both occasions, maximum values occurring after 15–30 min and returning to basal levels after 3 h. The maximum values attained and the area under the response curves were higher under anaesthesia. LRH stimulation resulted in a 15- and 30-fold increase in serum levels of biologically active LH, with and without anaesthesia, respectively. Basal levels were not significantly different on the two occasions. The area under the LH response curve was higher in 3 of the 4 monkeys without anaesthesia. The extent to which results in conscious monkeys are affected by stress is difficult to assess. Since neither handling technique allows for the collection of 'true' basal data, it is paramount to standardize and define the conditions under which experiments, and even routine blood sampling, are performed in male rhesus monkeys.

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