Taste aversions to mother's milk: the age-related role of nursing in acquisition and expression of a learned association.

The development of taste aversion learning to novel cues contained in mother's milk was examined in rat pups. Pups receiving distinctive mild by experimenter-delivered oral infusions followed by toxicosis formed an aversion to the dam's diet. Robust aversions were learned as early as Day 10 and were retained for at least 11 days. When the same distinctive milk was obtained directly from a foster mother through nursing, however, only weanling-age pups (over 20 days) formed an aversion. X-ray analysis of nipple location in the mouths of suckling pups suggested that pups between the ages of 10 and 21 days receive milk at a similar tongue locus. Flavored milk was then delivered at specific time intervals in controlled quantities through tongue cannulas implanted at loci corresponding to the nipple position shown by the X-rays. Cannulated preweanling pups that were attached to a nipple during milk delivery failed to associate the taste cue with illness, whereas both preweanlings off the nipple and weanlings on the nipple acquired aversions to the taste cue in the milk. The evidence obtained in these experiments suggests that pups of all ages are incapable of expressing a taste aversion in a nursing situation and that preweanling pups in particular are also dificient in acquiring aversions within a suckling context. The inability of preweanling pups to acquire taste aversions in a nursing situation appears to result from a failure to associate taste cues with illness rather than a failure to detect taste cues obtained from a nipple.     

Generalized and specific expectancies: Sequential mediators of interpersonal behavior1

Two experiments confirmed sequential mediation of social interaction by investigating the effects of generalized expectancies on specific expectancies and the effects of specific expectancies on performance. Both experiments used a simulated tutoring task in which the subject took the role of tutor while a confederate took the role of student. In Experiment 1 subjects combined generalized expectancies about the effectiveness of certain tutoring responses with specific situational information to produce specific expectancies about the results of the tutoring responses under the experimental circumstances. Experiment 2 replicated this finding and showed that specific expectancies of the relative effectiveness of different responses influenced which response was performed more. Results were discussed in terms of cognitive motivation theory and social learning theory.     

Some problems of Wilson's disease

The Leipzig Center for Wilson's Disease in the GDR is charged with the registration and diagnosis of all homozygous Wilson gene carriers, the clarification of all suspected cases, including the heterozygote test, and the co-ordination of long-term treatment. At present, there are 78 recorded Wilson gene carriers living. On the basis of our own comprehensive observations and investigations over prolonged periods of time, questions concerning pathogenesis, genetics, diagnosis and therapeutic measures, including their side-effects, are dealt with.     

Differential indication of trimipramine - results of a controlled multiclinical study]

The antidepressants trimipramine and imipramine were compared within the framework of a multiclinical study performed under the conditions of a controlled clinical experiment. There has been found a time-different remission of affective und psychomotoric symptoms. The panthymoleptic action of trimipramine and other antidepressants is discussed with reference to these results. Trimipramine influences psychotic states, especially if in depression anxiety is combined with agitation, also in hypochondriac forms of depression.     

An adolescent symptom checklist for juvenile deliquents

A rating instrument was developed to assess the personality functioning of problem adolescents who have a brief history of official delinquency. Subjects were 186 residents at a short-term diagnostic detention facility. The instrument that emerged from a factor analysis was tested for reliability, validity, and cross-situational generality. Two major orthogonal factors emerged, Apathy-Withdrawal (I) and Anger-Defiance (II). Each factor was found to be congruent with the corresponding dimension on behavior rating instruments that had previously yielded two orthogonal factors and that had been shown to be relevant to a large number of psychological and educational issues. Significant correlations between the factors and a series of global ratings measuring behavior and measures indicative of the frequency and seriousness of official delinquency provided further evidence of construct and discriminant validity as well as evidence of cross-setting consistency of personality functioning.     

The generality of learned helplessness in the rat

Two experiments were simultaneously conducted in which two different groups of 40 rats each were exposed to one of two different stressors. In both experiments half the subjects were pretreated with shock, half with underwater exposure. For each pretreatment stressor, half the subjects were allowed to escape, the other half were not. The experiments differed in the test task used. Approximately 24 hr after pretreatment, one-half the subjects from each pretreatment group received 20 water-escape trials in an underwater maze, the other half received 20 shock-escape trials in a two-way shuttle box. The subjects in each of the inescapable pretreatment conditions were slower to escape in the subsequent shock-escape and water-escape tasks when compared with subjects in the corresponding escapable pretreatment condition. The “learned helplessness” effect appeared to be no smaller when aversive stimuli were changed between pretreatment and test than when they remained the same.     

Epilepsy by looking at patterns]

The author, after pointing out the rare occurence and peculiarities of pattern-sensitive forms of epilepsy, reports the case of a seven-year-old boy with infantile cerebral paresis characterized by symptomatic attacks, who was observed to show absence-like conditions when looking at small-checkered patterns of nylon fabric. Grasping and looking at such fabrics assumed the form of an addiction, with a sense of pleasure being believed to be derived therefrom. Although anticonvulsive therapy resulted in attacks of epilepsy being no longer detectable clinically and by electroencephalography, seizures were still triggered by looking at patterns. Also discussed in this article is the problem of transition from real to psychogenic attacks.