Components Of Stereotype Research Articles

Sex-trait stereotypes in the self-and peer descriptions of third grade children

Previous studies have indicated that third-grade children have an appreciable knowledge of sex-trait stereotypes, that is, psychological traits which are differentially associated with men and women in our culture. The present study was designed to assess the degree to which children of this age employ sex-stereotyped traits in their descriptions of themselves and their peers. Subjects were 88 third-grade children, 44 boys and 44 girls, tested by male and female examiners. Each child was administered a self-description measure and a peer description measure, both of which were modifications of the Sex Stereotype Measure (SSM) used in earlier studies assessing children's knowledge of adult-defined stereotypes. Results indicated that both boy and girl subjects generally attributed male traits to boy peers and female traits to girl peers. Sex differences were found on the self-description measure, where girl subjects generally saw their behavior as more similar to female traits than male traits, while boys generally saw their behavior as equally similar to both. This asymmetry in the degree of stereotyping in boys' and girls' self-descriptions is discussed in terms of the relatively more “adult” (and perhaps “unnatural”) components of the male stereotype and the greater difficulty in socializing children to conform to the model which it provides.

Differences in the nature of the stereotyped behaviour induced by aporphine derivatives in the rat and in their actions in extrapyramidal and mesolimbic brain areas

Apomorphine, (-)-N-n-propylnorapomorphine [(-)-NPA] and (±)-N-n-propylnorapomorphine [(±)-NPA] each caused stereotyped behaviour patterns in the rat which could be differentiated into two components, sniffing and repetitive head and limb movements (low intensity component) and gnawing, biting and licking (high intensity component). Low intensity components occurred at low doses of apomorphine and high intensity components at larger doses but the two components never occurred independently for (-)-NPA or (±)-NPA. Biting was the predominant effect of these agents which were shown to be at least twenty times more potent than apomorphine. The (-)-isomer of NPA was the more potent. The two components of stereotypy were differentiated both pharmacologically (using amantadine, reserpine plus α-methyl-p-tyrosine and haloperidol) and by lesions placed in areas of the extrapyramidal (caudate-putamen, globus pallidus, substantia nigra) and mesolimbic (nucleus accumbens septi, tuberculum olfactorium, nucleus amygdaloideus centralis) systems. However, both sniffing and biting responses were reduced by lesions of the serotonergic raphe nuclei. The two stereotypic components were differentially induced by intracerebral injections of apomorphine and (-)-NPA into the caudate-putamen, nucleus accumbens septi and tuberculum olfactorium. Injections into the central nucleus of the amygdala were ineffective. The degree of involvement of the different areas was shown to differ for apomorphine and (-)-NPA, in particular the nucleus accumbens septi appeared more important for the action of (-)-NPA and the tuberculum olfactorium for apomorphine. Intracaudate (-)-NPA was less active than apomorphine but, generally, intracerebrally applied (-)-NPA was twice as potent as apomorphine. Both (-)-NPA and apomorphine caused circling behaviour in animals with asymmetric medial raphe nucleus lesions (contralateral) or unilateral lesions of the substantia nigra (ipsilateral). In these experiments (-)-NPA was ten times more potent than apomorphine.

The deimatic reaction in the praying mantis Stagmatoptera biocellata

When the mantid Stagmatoptera biocellata is shown a foe, the insect displays a characteristic response called the deimatic reaction (DR) (Fig. 1). A systematic study of the response is presented in this paper. 1. The full display is an assembly of seven independent and very stereotyped components. The lesser the strength of the reaction, the smaller the number of components. They disappear in a stereotyped order. 2. The occurrence of the DR proved to be highly predictable using birds as releasers (i.e. troupials, shiny cow-birds, Java sparrow and canarys). But the DR was also induced by the back projection of real or filmed shiny cow-birds silhouettes. Only a film taken and projected at 100 frames a second induced a DR as a “real” stimulus. 3. A DR is immediately induced by a bird presented for 2 minutes. The response duration exceedes the presentation interval. The leftover time ranged from few seconds to 45 minutes. When the insect and the predator were faced for long time, the DR was displayed as long as the stimulus was shown and a response that lasted 6 hours was recorded. Some conclusions were deduced from testing crude interferences in the nervous system (Fig. 3). Namely, that the DR can be elicited either by visual and tactile stimuli, and that the movements involved in the display are not coordinated with each other in a closed-circuit system. This finding is discussed in connection with an hypothesis put forward by Vowles (1961). 4. The survival value of the DR is analyzed and the paper concludes, unlike previous reports, that the over-all effect of the display is to frighten the foe.