William R. Thompson

Some Effects on Offspring Behavior of Maternal Adrenalin Injection During Pregnancy in Three Inbred Mouse Strains

Much recent work in physiology has been concerned with the experimental production in animals of congenital malformations by administration of various teratogens to the pregnant mother (Kalter & Warkany, 1959). There is no doubt that a great variety of agents produce an equally great variety of defects in the young, the nature and extent of these defects depending on such factors as trimester of administration, size of dosage, genotype of the animal, and a number of others. Relatively little has been done, however, on the effects of maternal stress during pregnancy on behavior of the offspring, although this is clearly a problem of some importance. The few experiments that have been reported (Furchtgott & Echols, 1958a, b; Meier, Bunch, Nolan, & Scheidler, 1960; Doyle & Yule, 1959; Thompson & Sontag, 1956; Thompson, 1757; Vincent, 1758) suggest that stress undergone by rat mothers during pregnancy can affect a number of behavior traits in offspring. But since these observations have been limited, there is a great need for additional information. This study is a preliminary attempt to examine the effects on the offsprings activity-level of prenatal maternal stress, and the relations of any such effects to genotype. It is hoped that this exploratory study will lead to more work on the problem.

Behavioral Effects of Maternal Adrenalin Injection during Pregnancy in Rat Offspring

A study by Thompson and Goldenberg (1962) previously reported in this Journal described changes in the adrenal weights of offspring resulting from injection of rat mothers with adrenalin during pregnancy. This report presents a summary of behavioral data gathered on these same animals. While there now seems little doubt that stress during pregnancy can produce behavioral changes in offspring (cf. Thompson & Goldenberg, 1962; Montague, 1962), there still remains a good deal of ambiguity as to which components of stress have the greatest importance. In this report we describe the possible relationship between two stress parameters-intensity and trimester of adminiscracionand behavioral effects in offspring.

Effects on rat offspring of maternal phenylalanine diet during pregnancy

Abstract 1. (a)|Phenylalanine administered to mother rats during pregnancy is associated with behavioral effects on offspring; these appear to relate to the domain of temperament rather than of intelligence. Such a finding is in line with those of other investigators as cited above; 2. (b)|At the dosage levels used, no specific chemical effects on phenylpyruvic acid excretion are noticeable in offspring. This is not to say, of course, that no effects of any kind exist; 3. (c)|The initial behavioral effects appear to diminish with age.

Some Physiological Effects of Maternal Adrenalin Injection during Pregnancy in Rat Offspring

It is now well known thar, in many species, the fetus is susceptible to a variety of agents administered to the mother during pregnancy. These include drugs, hormones, atmospheric changes, ionizing radiation, infectious diseases, and a large number of other factors. The equally great range of effects takes in such anomalies as cleft palate, malformed limbs, absence of eyes, spina bifida, and many others (Fraser, 1958; Kalter & Warkany, 1959). More recently, some work has begun to be devoted to behavioral changes produced by various stresses during pregnancy. At the psychiatric or human level, several workers have obtained evidence that there occurs a higher than normal incidence of psychological maladjustments in children born of unfavorable pregnancies, such as involve not only physiological difficulties like toxemia and hemorrhaging, but also components of psychological stress (Sontag, 1941; Rogers, et al., 1955; Lilienfeld, et al., 1956; Pasamanick, et al., 1955, 1956; Scotc, 1958, 1959; Kawi, et d., 1959; Knoblock & Pasamanick, 1961 ) . Similarly, in animals, a number of investigators have established that drugs (Hamilton & Harned, 1944; Hamilton, 1945; Armitage, 1952; Werboff, et al., 1961a, b, c ; Thompson & Olian, 1961), anoxia (Becker, et al., 1952; Meier, et al., 1955, 1960), radiation (Levinson, 1952; Furchtgott & Echols, 1958a, b; Furchcgott, Echols, & Openshaw, 1958; Sharp, 1961 ) , alcohol (Vincent, 1958), audiogenic seizures (Thompson & Sontag, 1957), and conditioned anxiety (Thompson, 1957; Doyle & Yule, 1959; Hockman, 1961 ), when administered to rat mochers during pregnancy, can produce a variety of behavioral changes in the offspring. Many of these studies, particularly those done with humans, have not adequately controlled for postnatal rearing or genetic effects. Consequently there is a pressing need for addi:ional empirical work involving suitable controls on the behavioral and physiological effects of stress during pregnancy. The study to be reported was thus aimed, first of all, at helping to meet this need. A second purpose of the study was [o explore, in the context of che prenacal influence problem, some of the essential features of the stress-response, both in mothers and offspring. It is possible that many of the effeco produced in offspring by an agent administered to the pregnant mother depend not so much on the specific features of the agent as on its more general stress effects. One of the major chemical compounds involved in the stress-response of an organism is

Imprinting and the “law of effort”

Abstract Three experiments were designed to test Hesss notion that strength of imprinting is related to effort expended by the chick during initial following. Comparisons were made between imprinting scores by chicks trained under different conditions as follows: ( a ) chick following moving object; ( b ) chick confined in plastic box moving behind a moving surrogate; ( c ) chick confined behind screen and exposed to moving surrogate; ( d ) chick and surrogate both stationary. Data from all three experiments indicated strongly that chicks trained under the first set of conditions showed superior imprinting. Those trained with stationary surrogates showed lowest imprinting scores. The results were taken as agreeing with, though not confirming Hesss “Law of Effort”, since they do not demonstrate conclusively the greater importance of efferent as opposed to afferent variables.

EFFECT OF LACK OF VISUAL STIMULUS VARIATION ON EXPLORATORY BEHAVIOR IN THE ADULT WHITE RAT

The idea that organisms often are motivated to seek external stimulation for its own intrinsic value, apart from serving any apparent biological need, is not a new one. However, present day explanations of the mechanism behind exploratory behavior are at sharp variance with one another. . Myers and Miller (6) conceive of exploratory behavior as a function of an internal drive stimulus rather than one external to the organism. As tension-reductionists, they argue that exploratory behavior is motivated by a disequilibrium within the organism and can be categorized with the primary drives of hunger, thirst, and sex. They maintain that a monotonous environment produces a tension state called boredom which is capable of initiating motor behavior leading to new stimuli, thereby increasing sensory variation. Boredom, as a persistent stimulus, is consequently reduced, and the behavior is reinforced. However, Harlow ( 3 ) contends that exploratory and manipulatory behaviors are functions of drives unlike the classical ones of sex, hunger, and thirst. He argues that they are not homeostatic and that their source of stimulation originates outside the organism. This stimulation initiates the behavior, sustains it, and also serves as a reward. Any resultant learning is a function of contiguity rather than drive reduction. Hence his explanation of exploratory behavior emphasizes the role of externally elicited motives. One way of testing the foregoing hypotheses is to deprive the animal of those stimuli which are assumed to reward or establish exploratory behavior. Berlyne ( 1) reported that 10 min. of confinement had no effect on exploratory behavior in the rat. In a developmental type study, Montgomery and Zimbardo (5) found that depriving rats of stimulus variation for relatively long periods after weaning had no effect on subsequent exploratory behavior. Butler (2) discovered that short stimulus-deprivation periods served to increase exploratory behavior in the Rhesus monkey. The conflicting results reveal clearly the necessity of further investigation. The purpose of this experiment was to determine whether a relatively

Imprinting: Its Effect on the Response to Stress in Chicks

Young chicks imprinted to surrogate mothers were compared with nonimprinted controls on two tests designed to measure resistance to stress. Half of each group was run with and half without a surrogate present during the stress. One test involving survival time under starvation showed no effects. However, in the other test, imprinted chicks showed fewer distress calls in response to auditory stimulation than nonimprinted controls.