Ontogeny of cholinergic mediation of behaviors in the rat.

In a series of six experiments, cholinergic mediation of behavior was studied in immature rats. It was found that although scopolamine disrupted discriminative choice behavior in both 15- and 23-day-old rat pups, it increased latency to choice in 15-day-olds and decreased latency to choice in 23-day-olds. This disruption of discriminated choice behavior was not due to differential shock thresholds or differences in locomotor activity between drug-treated and control animals, nor was it specific to a T-maze shock-escape discrimination task. These results suggest that central cholinergic mediation of different behaviors may mature at different rates.     

Relationship between sex, age, education and field-dependence: a cross-cultural comparison

Past examination of the relationship between field-independence and age has indicated a developmental trend of increased field-independence up to 17 yr., with a movement toward greater field-dependence after this point. However, discrepancies between longitudinal and cross-sectional findings suggest that this relationship may be confounded by socioeconomic variables. The present study examined the age/field-dependence relationship in a sample of Northern Italians controlling for educational background. Results for females indicated statistical control of educational variables modified the age/field-dependence relationship, but did not for the male sample.     

Levels of experienced dimensionality in children and adults

This work presents a new conceptualization of the contrast between holistic and differentiated perception of multidimensional stimuli. Specifically, two hypotheses about the experiential status of dimensions within holistic perception are proposed and tested as explanations of young children's general perceptual mode and adults' integral mode. The major result is that three levels of dimensional status are realized: (1) the hypothesis of nonprimary axes characterizes adult “integral” perception of saturation and brightness relations, (2) the hypothesis of primary but not mandatory axes characterizes kindergarteners' “integral” perception of size and shade relations, and (3) the notion of mandatory axes characterizes adults' separable perception of size and shade relations. These results indicate a new interpretation of the integrality-separability distinction and the derivative developmental hypothesis. It is specifically hypothesized that the developmental history of most dimensional combinations includes these three levels.     

Effects of 6-hydroxydopamine lesions of the nucleus accumbens septi and olfactory tubercle on feeding, locomotor activity, and amphetamine anorexia in the rat.

Bilateral 6-hydroxydopamine lesions of the nucleus accumbens septi (NAS) and olfactory tubercle (OT) caused enhanced intake of wet mash in 23-hr-food-deprived rats tested in photocell activity cages during restricted 30-min sessions. This mild hyperphagia was accompanied by a significant hypoactivity in the group with NAS/OT lesions. No hyperphagia was observed during a prolonged 120-min test session or in free-feeding tests conducted in the home cage. Anorexia induced by d-amphetamine (.5 and 1.5 mg/kg) was unaltered by the lesion, although the locomotor stimulant action of the drug was attenuated. A second experiment showed that the NAS/OT lesion also enhanced food intake in the photocell cages during 30-min sessions with dry food pellets but that food-associated drinking was concomitantly reduced. The results are consistent with the hypothesis that the behavioral changes caused by mesolimbic neuron destruction result in part from an inability to switch from one behavioral activity to another.     

Is there a developmental trend from integrality to separability in perception?

Some previous literature suggests that young children perceive in an integral, holistic fashion stimuli that older children perceive in a separable, dimensionalized mode. A prediction from a strong form of this position is that younger children actually may perform more rapidly a speeded classification task that requires “condensation” than a task that requires “filtering” (if the similarity relations among the wholes favor the former task). Older children should be able to take advantage of the simple unidimensional basis of the filtering task and thus accomplish it much more rapidly than the condensation task. The results are only partially in accord with the predictions. Kindergarteners (5 years of age), on size-and-brightness stimuli, show no speed advantage on either task, while second (8 years) and fifth (11 years) graders clearly show more rapid filtering. Therefore, the developmental hypothesis is in need of some revision and elaboration. Some stimuli are less separable for younger than for older children, but even five year olds can access their dimensional structure under some conditions.     

The genesis and use of exemplar vs. prototype knowledge in abstract category learning

Accurate classification of new exemplars in an abstraction paradigm may be due to their similarity to old exemplars rather than to abstract category (or prototype) knowledge. In the present study, subjects received initial training on a two-category problem before being transferred to a task in which half of the exemplar-response pairs had their responses reversed while the remaining half of the pairs were unchanged. When transfer occurred with no delay and involved old exemplars, more errors occurred for changed than for unchanged pairs. This result implies the use of exemplar-specific rather than abstract category knowledge. However, when transfer was delayed by 24 or 72 h, errors occurred equally often for changed and unchanged pairs. This result suggests that exemplar-specific knowledge is no longer used. Since subjects were still able to accurately classify exemplars prior to the transfer task at these delays, some form of abstract category knowledge is implicated.     

“...and a Japanese wife.” Social structural antecedents of women's role values in Japan

Japanese women were asked to rank the relative importance they place on the role of wife, mother, woman, and person as well as the relative importance they believe their husbands place on similar male roles. Also asked were questions on the qualities of a good wife, the tone of interpersonal relationships with husbands, and the division of household responsibilities. Findings support the hypothesis that social structural variables related to environmental complexity result in an emphasis on individuality. Furthermore, although the Japanese wife's uncomplaining acceptance of household chores and responsibilities appears to make her fit the stereotype of the selfless domestic desirous of filling her husband's every wish, she seems to be more a disinterested than a willing servant, her husband being nowhere as important a factor in her social and psychological existence as are her children.     

A continuum of dimensional separability

Recent studies of children’s perception may be interpreted in terms of a developmental continuum from integrality to separability in the perception of multidimensional variation. Two experiments examined the existence of such a continuum in adult perception. The first experiment indicated that there are dimensional combinations that are neither clearly integral nor separable for adults. Rather, such a combination results in performance patterns intermediate between those found with integral and separable dimensions. The second experiment tested one conceptualization of a continuum of dimensional separability in a speeded classification task. By this conceptualization, the perceived structures of multidimensional variation are orderable by thedegree to which the component dimensions are differentiated. Consistent with this view, performances with three-dimensional combinations are shown to be differentially dependent on dimensional and wholistic relations. The importance of the joint consideration of developmental and adult issues in the perception of multidimensional variation is briefly discussed.     

Ethology,ethogeny, etics,emics, biology,culture: On the limitations of dichotomies

Ethogeny, supposedly patterned on ethology, differs as an approach to human social behaviour in obvious respects. Ethogenists follow an emic research strategy, whereas human ethologists have strongly favoured etic research options. However, recent trends to a broader, evolutionary approach in human ethology suggest that an avoidance or rejection of verbal reports and ethogenic methods merits reconsideration, The distinctions involved in the eticlemic contrast are examined, and compared to Richer's distinction between D- and N-type agreements. It is argued that none of the distinctions are dichotomous. The useful aspects of the distinctions refer to the generality of findings, and the validity of evidence. Bearing these in mind, ethogenic methods have a place in a broader human ethology. So far as validity is concerned, the value of a comparison of information from different sources, such as verbal and non-verbal data, is stressed. So far as generality is concerned, ethogenists may consider this to be very limited because of idiosyncratic cultural factors in the causation of human social action. A reconsideration of the biology/culture dimension in terms of function rather than causation may lead to more optimism in this respect, and be more productive scientifically.