The motivation to breastfeed: a fit to the opponent-process theory?

The opponent-process theory, a dynamic model of acquired motivation presented by Solomon and Corbit (1974), was applied to the process of breastfeeding. A modified form of the Nowlis Mood Adjective Checklist (MACL, Nowlis, 1965, 1970) and a discomfort measure were used in assessing through recall the affective course predicted by the theory. The data were analyzed using multivariate analysis of variance (MANOVA) and correlational procedures. Results were highly significant: Women who breastfed for relatively long periods recalled positive affective responses while the baby was at breast and a subsequent negative or dysphoric response. The additional characteristics of acquired motivation, habituation, and withdrawal, were also evidenced in the data. As a control for possible confounding demand characteristics inherent in the methodology, a sample of childless women was surveyed using an "as-if" form of the same questionnaire. Very little similarity to the breastfeeders was found in the pattern of responses yielded by this group. It was concluded that our major findings are quite likely free of influence from this source.     

Cognitive problem-solving and life event correlates of depressive symptoms in children

This study examined the relationship between a number of cognitive problem-solving and life event variables and depressive symptoms in a sample of non-referred grade school children. The results indicated that higher levels of depressive symptoms were associated with an external locus of control, increased levels of objective and subjective life stress, and lower performance levels on an impersonal problem-solving task. Level of depressive symptoms was also found to be inversely related to socioeconomic status as measured by father's occupation. Contrary to prediction, no consistent relationship was found between depression and interpersonal problem-solving ability.This research is based on the first author's master's thesis submitted under the supervision of the second author to the Department of Psychology, University of Missouri-Columbia.     

Ambient Green and Creativity

This research examined an important applied question: whether viewing ambient green (relative to red) on the wall of a workspace would facilitate creativity. A methodologically sound experiment revealed no influence of green on creativity. Care must be taken when interpreting a null result, but these data do not provide support for the presence of a relation between ambient green and creativity. This research also highlights the need for more research in the area of ambient color and psychological functioning, and the need for caution regarding the tendency to move to real-world recommendations before a firm empirical base is established.     

Quantifying disablers in reasoning with universal and existential rules

People accept conclusions of valid conditional inferences (e.g., if p then q, p therefore q) less, the more disablers (circumstances that prevent q to happen although p is true) exist. We investigated whether rules that through their phrasing exclude disablers evoke higher acceptance ratings than rules that do not exclude disablers. In three experiments we re-phrased content-rich conditionals from the literature as either universal or existential rules and embedded these rules in Modus Ponens and Modus Tollens inferences. In Experiments 2 and 3, we also used abstract rules. The acceptance of conclusions increased when the rule was phrased with “all” instead of “some” and the number of disablers had a higher impact on existential rules than on universal rules. Further, the effect of quantifier was more pronounced for abstract rules and when tested within subjects. We discuss the relevance of phrasing, quantifiers and knowledge on reasoning.     

A new exodus? Explaining Jewish migration from Europe after the Cold War

Why are European Jews migrating to Israel in significant numbers? Israeli leaders and popular press reports suggest that incidents of antisemitism have reached such high levels across Europe, even in fully democratic countries, that Jews are leaving once again to escape persecution and violence. Others suggest that Jews are migrating for the same reasons other migrants do: for greater economic opportunity. Until now, we have had no way of weighing the relative merit of these claims, hampered by the absence of reliable comparative data on antisemitism in Europe. Leveraging a new dataset compiled by the author, this study tests these competing hypotheses and finds that European Jews migrate because of greater economic opportunity in Israel. While concerns about antisemitism in Europe are at record highs and more Jews are considering moving to Israel than ever before in the post-war era, so far most Jewish migration is to take advantage of better economic opportunities in Israel.     

Common mechanisms in error monitoring and action effect monitoring

In the present study, we considered error-related brain activity in event-related potentials, to investigate the relationship between error monitoring—that is, the detection and evaluation of erroneous responses—and action effect monitoring—that is, monitoring of the sensory consequences of behavior. To this end, participants worked on a task-switching paradigm that consisted of a free-choice task, in which a puzzle piece had to be attached to an existing one (the prime task), and a subsequent color flanker task (the probe task). We examined whether unexpected action effects in the prime task would affect the subsequent error monitoring in the probe task. We found the neural correlates of error monitoring during the probe task, the error-related negativity as well as the error positivity, to be increased after unexpected action effects in the prime task. In contrast, the neural correlates of visual attention were decreased after unexpected action effects, in line with recent findings on an attenuation of sensory processing after errors. Our results demonstrate a direct link between monitoring processes in the two tasks. We propose that both error monitoring and action effect monitoring rely on a common generic monitoring system related to novelty detection or affective processing. Preactivating this system by means of unexpected action effects increases the sensitivity for detecting an error in the subsequent task.     

Effects of post-encoding wakeful rest and study time on long-term memory performance

Recent work shows that post-encoding wakeful rest, in contrast to a cognitive task delay period, supports memory performance. The present study aimed at investigating whether study time modulates the impact of post-encoding rest on delayed memory performance. Healthy young adults were allocated to one of two “study time” groups (fixed-paced vs. self-paced). Participants encoded two word lists. After immediate recall of one word list, participants wakefully rested for 8?min, after the other, they performed a visual problem solving task. A delayed recall took place at the end of the experimental session (Experiment 1) and again after 7 days (Experiment 1?+?2). We found that participants in the self-paced group outperformed those in the fixed-paced group. In Experiment 1, participants showed higher memory performances after 7 days in the resting condition independent of study time. No significant differences between post-encoding (rest vs. problem solving) and study time conditions were found in Experiment 2. Combined analyses of both experiments revealed that an additional recall (Experiment 1) supported memory retention in both post-encoding conditions. Our findings suggest that resting is beneficial over the long term, but only when the encoded information is repeatedly retrieved at the end of a learning session.     

Increasing organ donor registration rates by providing an immediate and complete registration opportunity: an experimental assessment of the IIFF model

The IIFF model of organ donation holds that the simultaneous presence of four factors directly influence donor registration: (1) immediate and complete registration opportunity (ICRO), (2) information, (3) focused engagement, and (4) favorable activation. Two field experiments examined the impact of an ICRO on organ donation registration. In Study 1, participants were at town halls where they knew organ donation was to be discussed. Registration cards were distributed and then collected at the end of the session in half of the town halls. For the other half, participants were asked to mail in completed cards. In three US cities, participants given an ICRO registered at a significantly greater rate (z?=?4.865, p?相似文献