Social modulation of learning in rats

It is well known that emotions participate in the regulation of social behaviors and that the emotion displayed by a conspecific influences the behavior of other animals. In its simplest form, empathy can be characterized as the capacity to be affected by and/or share the emotional state of another. However, to date, relatively little is known about the mechanisms by which animals that are not in direct danger share emotions. In the present study, we used a model of between-subject transfer of fear to characterize the social interaction during which fear is transmitted, as well as the behavioral effects of socially transmitted fear. We found that (1) during social interaction with a recently fear-conditioned partner, observers and demonstrators exhibit social exploratory behaviors rather than aggressive behaviors; (2) learning and memory in a shock-motivated shuttle avoidance task are facilitated in rats that underwent a social interaction with a partner that had been fear conditioned; and (3) a brief social interaction with a recently fear-conditioned partner immediately before fear conditioning increases conditioned freezing measured on the next day. The observed effects were not due to a stress-induced increase in pain sensitivity or analgesia. Collectively, these data suggest that a brief social interaction with a cage mate that has undergone an aversive learning experience promotes aversive learning in an otherwise naïve animal. We argue that socially transferred fear is an adaptation that promotes defensive behavior to potentially dangerous situations in the environment.Human empathy can be defined as the ability to experience and share the thoughts and feelings of others (de Waal 2008). Obviously, this is a complex social phenomenon that, until recently, has received much attention from philosophers and psychologists rather than neuroscientists (Decety and Lamm 2006). However, in its simplest form, empathy can be characterized as the capacity to be affected by and/or share the emotional state of another (de Waal 2008). Tuning one''s emotional state to that of another increases the probability of similar behavior, which thereby allows rapid adaptation to environmental challenges (Hatfield et al. 1994). This social adaptation may be particularly important for emotions that signal a potential danger, such as fear. Although one can learn about potentially harmful stimuli by directly experiencing an aversive event, observation or interaction with a conspecific in danger and/or in pain may also provide information about threats in the environment. There is a vast literature on learning about direct danger (Maren 2001) as well as sharing emotions through observation (see, e.g., Church 1959; Langford et al. 2006; Olsson and Phelps 2007). However, relatively little is known about the mechanisms by which animals that are not in a direct danger share emotions.We have recently designed an experimental rat model of between-subject transfer of emotional information (Knapska et al. 2006). In this model, rats are housed in pairs and one member of the pair (the “demonstrator”) is removed and subjected to fear conditioning. After the fear-conditioning episode, the conditioned animal is allowed to interact with its naïve cage mate (the “observer”). We showed that the demonstrator''s fear is socially transferred to the observer, resulting in both rapid increase in exploratory behavior of the observer and a pattern of c-Fos activation in the observer''s amygdala that parallels that of the shocked demonstrators.These results suggest that the social interaction between the demonstrator and observer results in a transfer of information that promotes aversively motivated learning in the observer. However, the nature of the social interaction and how it comes to influence aversively motivated behavior is not known. Therefore, the present study aimed to characterize the behavior of both the demonstrators and observers during their social interaction and further characterize the nature of the influence of socially transmitted fear on aversively motivated learning and memory. We hypothesized that the social interaction between observers and demonstrators would result in a social transfer of fear that would promote learning and memory of both active defensive responses (avoidance) as well as defensive immobility (freezing). To test this hypothesis, we carried out five experiments that examined the nature of the social interaction between shocked demonstrators and observers (Experiment 1), the acquisition and retention of active avoidance (Experiment 2), and conditioned freezing (Experiment 3). Because it is not clear if social transfer effects can be observed among unfamiliar animals and to control for social buffering, we also compared the social transfer of fear in familiar and unfamiliar rats (Experiment 4). To control for the possible influence of different pain sensitivity thresholds in the observers paired with shocked demonstrators, we carried out pain tests (Experiment 5).     

Are Some Psychotherapies Much More Effective Than Others?

In a previous paper we had reported on the examination of comparisons of 18 metaanalyses of active treatments with each other (Luborsky, Rosenthal, Diguer, et al., 2001). These metaanalyses gave a small and nonsignificant mean level of difference between types of treatments. The smallness of this correlation confirms Rosenzweig's (1936) expectation that because of the large overlap in effective ingredients of different psychotherapies, comparative studies of psychotherapies would show little difference. Such a comparison that includes psychoanalyses seems a long way off, but if outcomes of psychoanalyses are defined similarly to those in the other psychotherapies, the expected differences in outcomes may also be small.     

Children's scale errors: A by‐product of lexical development?

Scale errors occur when young children seriously attempt to perform an action on an object which is impossible due to its size. Children vary substantially in the incidence of scale errors with many factors potentially contributing to these differences, such as age and the type of scale errors. In particular, the evidence for an inverted U‐shaped curve of scale errors involving the child's body (i.e., body scale errors), which would point to a developmental stage, is mixed. Here we re‐examine how body scale errors vary with age and explore the possibility that these errors would be related to the size and properties of children's lexicon. A large sample of children aged 18–30 months (N = 125) was tested in a scale error elicitation situation. Additionally, parental questionnaires were collected to assess children's receptive and expressive lexicon. Our key findings are that scale errors linearly decrease with age in childhood, and are more likely to be found in early talkers rather than in less advanced ones. This suggests that scale errors do not correspond to a developmental stage, and that one determinant of these errors is the speed of development of the linguistic and conceptual system, as a potential explanation for the individual variability in prevalence.     

The chameleon effect,the temporal aspects of mimicry and their impact on service measurement

BackgroundIn an experiment conducted in a natural setting, we test the link between mimicry, the amount of time during which the mimicry behavior takes place, and its impact on service quality.MethodsCable TV clients (n = 120) were randomly assigned to six experimental conditions (2 mimicry conditions: verbal mimicry vs. no mimicry x 3 interaction time: 5 vs. 10 vs. 15 minutes). Perceived service quality served as the dependent measurement.ResultsA main effect of mimicry was found on service quality: a cable TV representative was perceived more favorably when he mimicked the customer. Importantly, it was shown that even small portions of mimicry are beneficial, meaning that practitioners do not have to mimic someone for a long time to achieve benefits.ConclusionThe paper shows new benefits for the mimicker: more positive judgments by the mimickee regarding the impact on several different levels of service quality.     

Context-dependent impairment of recollection in list-method directed forgetting

In list-method directed forgetting, people's ability to forget one of the sets of learned material is examined. Research shows that memory for to-be-forgotten items is impaired when assessed by a recall test and by recognition tests reliant on recollective processes. Retrieval inhibition and context-change mechanisms have been proposed to account for the directed forgetting effects and both of them account for the results obtained with recognition tests. However, the context change account makes a specific prediction that recollection is impaired by directed forgetting only if it makes use of contextual associations. In the present study, directed forgetting was examined with two types of recollection-based tasks making use of different types of associations, namely a list discrimination task utilising contextual associations and an associative recognition task utilising interitem associations. Consistent with the context change account, the costs of directed forgetting were observed in a list discrimination task and were not observed in an associative recognition task. The results indicate that impairment in recollection due to directed forgetting is not general and provide converging evidence to support the context-change account.     

Objective and epistemic gradability: Is the new angle on the Knobe effect empirically grounded?

According to the New Angle, any explanation of the Knobe effect must be gradable and asymmetric. It has been argued that only Hindriks’ approach meets both criteria. First, we argue that Holton’s hypothesis also meets the criteria. Second, we show that the authors are not justified in taking the criteria to be empirically justified. We have failed to replicate the asymmetry result in two experiments. Moreover, gradability can be objective or epistemic. We show that the New Angle presupposes objective gradability. In our experiments, the patterns of responses to questions about epistemic and objective gradability are the same, irrespective of whether the feature is objectively gradable (e.g., blameworthiness) or not (e.g., intentionality). Our results thus question the extent to which the New Angle is empirically grounded. Moreover, they raise doubt whether the answers to questions about epistemic and objective gradability can be taken at face value at all.

Abbreviations: NRH - normative reasons hypothesis; NVH - norm violation hypothesis; DQ - degree question; DAQ - degree of agreement question