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Biomedical subjects

G G Gallup

Publications and source records attributed to G G Gallup.

At least 37 records · Page 2Linked to original sources

Failure to find self-recognition in mother-infant and infant-infant rhesus monkey pairs.

To date, chimpanzees, orangutans, and humans are the only species which have been shown capable of recognizing themselves in mirrors. In an attempt to make the identity of the reflection more explicit we report two experiments in which rhesus monkeys were given paired access to a common mirror over an extended period. While developmental differences in mirror behavior were obtained, signs of self-recognition failed to emerge. The results were discussed in terms of the absence in monkeys of an essential cognitive category for processing mirrored information about the self.

Animals↗

Morphine potentiation of tonic immobility: effects of naloxone, PCPA, and 5,6-DHT.

The duration of tonic immobility in chickens, a catatonic-like state produced by brief restraint, was greatly potentiated by a single 1.0 mg/kg injection of morphine. Naloxone by itself, however, had no effect on tonic immobility, and only an exceptionally large dose of naloxone blocked the morphine potentiation. Pretreatment with PCPA and 5,6-dihydroxytryptamine completely eliminated the morphine enhancement. The effect of morphine on tonic immobility may be mediated by a central serotonergic-raphe system.

5,6-Dihydroxytryptamine↗

Pargyline and tryptophan enhancement of tonic immobility: paradoxical attenuation with combined administration.

Four experiments were conducted to examine the individual and combined effects of pargyline and tryptophan on the duration of tonic immobility in chickens. Injection of either compound alone produced a dose-dependent potentiation of tonic immobility. However, combined administration of pargyline and tryptophan resulted in a dramatic attenuation of the response and this effect was completely blocked by pretreatment with p-chlorophenylalanine. In addition to reducing the duration of tonic immobility, combined administration of pargyline and tryptophan produced a complex behavioral syndrome which may be analogous to that observed in mammals after similar drug treatment. These results suggest the need for a modification of the recently proposed serotonergic-raphe model of tonic immobility.

Animals↗

Absence of self-recognition in a monkey (Macaca fascicularis) following prolonged exposure to a mirror.

To date only chimpanzees, orangutans, and humans have been found capable of recognizing themselves in mirrors. In an attempt to provide a more definitive test of the capacity for self-recognition in monkeys. I gave a preadolescent crab-eating macaque 2400 hr of mirror exposure. However, patterns of self-directed behavior never developed and a more explicit test of self-recognition yielded negative results. The data indicate possible differences between great apes and monkeys in self-awareness.

Animals↗

Tryptophan and tonic immobility in chickens: effects of dietary and systemic manipulations.

Consistent with a serotonergic-midbrain raphe model of tonic immobility, four experiments designed to affect changes in serum tryptophan produced reliable effects on the duration of the response in chickens. Systemic injections of tryptophan, the dietary precursor to serotonin, led to a dose-dependent increase in immobility, with optimal effects being observed within 30 min after injection. Dietary depletion of endogenous tryptophan served to attenuate the duration of immobility, and a diet completely free of tryptophan, but supplemented with niacin, practically abolished the reaction. Dietary replacement served to reinstate the response. In a fifth experiment, tryptamine, an alternative metabolic by-product of tryptophan, was found to have no effect on immobility. The data are discussed in light of evidence showing serotonergic involvement in tonic immobility.

Administration, Oral↗

Habituation and tonic immobility in domestic chickens.

The habituation of tonic immobility in chickens was examined in six studies. It was shown that repeated elicitation of immobility, and not just handling, was responsible for reduced response durations after multiple exposures to manual restraint. Habituation was a function of the number of stimulus presentations and, in addition, proved surprisingly durable, with diminished reactions using lasting at least 2.5 mo. Strain differences were found in the number of trials required to reach a criteria of habituation, and habituation proceeded faster when immobility termination was self-paced as opposed to experimenter induced. Also, massed trials produced robust sensitization effects rather than diminished responsiveness.

Animals↗

Strain differences among chickens in tonic immobility: evidence for an emotionality component.

Substantial strain differences in tonic immobility were found between different breeds of chickens. Crossbreeding between strains showing different immobility durations yielded hybrids that exhibited intermediate reactions. For purpose of relating the strain differences in tonic immobility to more conventional measures of emotionality, data were collected on open-field activity, defecation, and adrenal weight. Overall, the results implicated strain-specific differences in emotionality as being the basis for the observed differences in immobility. Latency to defecate in an open field, however, was highly correlated with latency to ambulate. It was argued that defecation, rather than being an absolute measure of fear or emotionality, may in fact be an intermediate response to gradual fear reduction.

Adrenal Glands↗

Possible serotonergic mediation of tonic immobility: effects of morphine and serotonin blockade.

Small doses of morphine, within the range of 0.02 mg/kg to 10.15 mg/kg were administered to chickens (Gallus gallus) and the effect on the fear-based tonic immobility (TI) response determined. All doses at and above 0.13 mg/kg enhanced the TI response significantly above the levels produced for the 0.2 mg/kg dose and the distilled water control group. Administration of a single large dose of p-chlorophenylalanine prevented the morphine-induced enhancement of TI. It was suggested that serotonin systems mediate morphine effects on tonic immobility in chickens.

Animals↗

Tonic immobility in chickens: possible involvement of monoamines.

Tonic immobility in chickens was affected by a variety of drugs that act on monoaminergic systems. Compounds that enhanced the duration of tonic immobility were d-LSD, BOL-148, pargyline, and iproniazid; 5-hydroxytryptophan, p-CPA, and atropine had no effect. Injections of serotonin depressed response duration. A suggestive parallel was noted between the results of the present study and those of previous work reporting drug-induced suppression of raphe electrical activity. The data appear to implicate monoamines, especially serotonin, in the mediation of behavioral activation and suppression.

5-Hydroxytryptophan↗