Social learning and collective choice

To be pertinent to democratic practice, collective choice functions need not apply to all possible constellations of individual preference, but only to those that are humanly possible in an appropriate sense. The present paper develops a theory of humanly possible preference within the context of the mathematical theory of learning. The theory of preference is then exploited in an attempt to resolve Arrow's voting paradox through restriction of the domain of majoritarian choice functions.     

Separate verbal memory and naming deficits in attention deficit disorder and reading disability

In this study, verbal memory and naming abilities were investigated in reading disabled (RD) and control children who were characterized according to the presence or absence of attention deficit disorder (ADD). Results indicate that deficits in learning and memory for recently acquired information occur as a function of ADD rather than RD while deficits in naming are specific to RD rather than ADD. We conclude that ADD is a major source of additional and separate cognitive morbidity in RD children.     

Specific language impairment in children: A cross-linguistic study

A common profile in English-speaking specifically language-impaired children is a moderate deficit across a broad range of linguistic features and a more marked, selective impairment in using bound morphemes and components of the verb system. To gain a clearer understanding of the nature of these more serious problems, we examined the speech of monolingual Italian-speaking as well as English-speaking children with specific language impairment. The evidence suggested that phonological factors contributed significantly to these children's extraordinary problems with particular linguistic features. Contrary to expectations, other marked deficits seemed more related to the opacity of the rules involved and homonymity with other morphemes than to problems with formal grammatical devices in general or components of the verb system in particular.     

The effects of continuous phonation on Xenon-inhalation air curves (of the kind used in deriving regional cerebral blood flow)

Regional cerebral blood flow (rCBF) may be measured with inhalation techniques that use end-expired values of radioactivity to estimate the isotope concentration in arterial blood. These end-expired data are used as an input function in a mathematical equation to derive rCBF. End-expired air is assumed normally to be in equilibrium with the arterial blood at the alveolar surface of the lung during regular (passive) breathing; this assumption may not be valid during continuous phonation. We therefore have analyzed breathing (inhalation/exhalation) patterns and end-expired radioactivity (¹³³Xe) during (1) speaking, (2) singing, and (3) humming of the national anthem, and also during (4) passive breathing. Statistically significant differences in breathing patterns were measured between a group of nonmusicians and two groups of musicians (singers) during the phonation tasks: The nonmusicians breathed more often (and more rapidly) and exhibited less variability in their breathing patterns than did the musicians. Notwithstanding these differences, the shapes of smoothed functions derived from the end-expired values were not influenced appreciably during phonation (except possibly during talking). The latter finding suggests that estimates of rCBF derived with these data should not be confounded seriously because of the continuous phonation.     

Risk factors and the Child Behavior Checklist in a child mental health center setting

The relationship between risk factors and the severity and type of childhood disorder, as measured by parent-completed Child Behavior Checklists, was examined for 768 children, ages 4–16, seen at a child mental health center. Regression analyses revealed no significant relationships between any combination of risk factors and the total number of behavior problems, internalizing, or externalizing scores for the entire group, males and females separately, or for the age and sex groupings of 6- to 11- and 12-to 16-yearolds. Chi-square tests revealed no relationship of profile type with any risk factor or with total number of risk factors. Implications for broad-based child assessment and risk factor research within a clinical population are discussed.We wish to thank Orin Bolstad, Linda Magnuson, and Julian Taplin for their assistance in this project.     

Anisomycin impairs long-term working memory in a delayed alternation task

A long-term temporal component of working memory of rats trained on the radial maze has been shown to be susceptible to disruption by the protein synthesis inhibitor, anisomycin. It is not clear whether protein synthesis played a role in working memory because accurate performance on the radial maze required the storage of a large amount of information, or because the information was to be held in store for relatively long periods of time. This experiment tested these hypotheses by assessing the effect of anisomycin on choice accuracy in a comparatively simple spatial delayed alternation task. Results indicate that under the present training conditions, protein involvement in working memory is related more to the length of the retention interval than to the amount of information retained.     

Evidence for aggression-modulating pheromones in prepuberal pigs

A series of behavioral bioassays were conducted to determine the aggression-influencing properties of urine and other fluids. Subjects were prepuberal castrated male and female domestic pigs from commercial stocks. In the behavior assay, pigs were painted with a test fluid and grouped for a videotaped 90 min observation period. Experiment 1 validated use of videotape recording by showing that duration of aggressive behavior registered live was correlated with that obtained from video records (R = .98). In experiment 2, urine and plasma collected from actively aggressive pigs reduced the durations of aggressive behavior of test pigs compared with the effects of urine and plasma collected from socially stable, handled pigs. In Experiment 3, a new set of test pigs confirmed that urine from fighting pigs reduced the duration of attack by test pigs compared with urine from nonfighting, handled pigs. In addition, the suggested reproductive pheromone, 5 alpha-androst-16-en-3-one, substantially reduced the duration of attack. The effects of gender and aggressive state of urine-donor pigs on test pigs was determined in Experiment 4. Again, urine from castrated male and female aggressive pigs reduced attack by test pigs compared with the level of attack shown by test pigs coated with urine from handled castrated males and females. Urine from fighting and nonfighting intact males had similar effects on test pig aggression. In Experiment 5, urine was obtained from nonhandled, socially stable pigs in their home pens and again from the same pigs after they had been regrouped (aggressive). These urine types had no significant influence on test pigs' aggression over the entire 90-min observation. However, during the first 30 min nonhandled, nonfighting pigs' urine induced less aggression in test pigs than did urine from fighting pigs. Results indicate that urine and blood plasma from aggressive pigs reduces aggression by test pigs compared with the effects of urine from handled pigs. Handling may increase the aggression-promoting properties of urine, and aggression may inhibit this aggression-promoting property.     

The relationship of affiliative arousal to dopamine release

Higher levels of affiliation motivation after exposure to affiliative films are significantly related to higher dopamine concentrations in saliva in one study of 61 college students of both sexes, and in plasma in another study of 47 adults of both sexes. Individuals high in dispositionaln Affiliation, if they also reported high life stress, showed high gains in dopamine concentration in plasma after exposure to an affiliative film significantly more often than other individuals. Since aroused affiliation motivation was not associated with higher concentrations of norepinephrine, epinephrine, or cortisol in either study, it appears likely that dopamine is especially associated with arousal of affiliation motivation, just as norepinephrine has been found to be associated with arousal of power motivation. Thus, different motives may be subserved by different hormones, making it unlikely that all motives lead to the same state of physiological arousal.This research was carried out when all the authors were connected with the Department of Psychology and Social Relations at Harvard University. We acknowledge with thanks the support of the John D. and Catherine T. MacArthur Foundation through a grant to the senior author.