“We” are not stressed: Social identity in groups buffers neuroendocrine stress reactions

The presence of others in threatening situations can be a mixed blessing since it is not always perceived as supportive but can also impair well-being. Building on the social identity approach, we tested the idea that the presence of others has a buffering effect on neuroendocrine stress reactions only if a sense of shared social identity is evoked. Therefore, the salience of social versus personal identity was manipulated. To induce social-evaluative stress, the Trier Social Stress Test for groups (TSST-G) was employed, while in the control conditions the Placebo-TSST-G was used. As predicted, social identity salience attenuated the stress-induced cortisol reaction in the TSST-G condition. By contrast, there was no effect of identity salience in the Placebo-TSST-G conditions. These findings provide the first experimental evidence for the idea that being part of a group buffers neuroendocrine stress only if group members develop a sense of shared social identity.     

Single prolonged stress disrupts retention of extinguished fear in rats

Clinical research has linked post-traumatic stress disorder (PTSD) with deficits in fear extinction. However, it is not clear whether these deficits result from stress-related changes in the acquisition or retention of extinction or in the regulation of extinction memories by context, for example. In this study, we used the single prolonged stress (SPS) animal model of PTSD and fear conditioning procedures to examine the effects of prior traumatic stress on the acquisition, retention, and context-specificity of extinction. SPS administered one week prior to fear conditioning had no effect on the acquisition of fear conditioning or extinction but disrupted the retention of extinction memories for both contextual and cued fear. This SPS effect required a post-stress incubation period to manifest. The results demonstrate that SPS disrupts extinction retention, leading to enhanced fear renewal; further research is needed to identify the neurobiological processes through which SPS induces these effects.     

Ambivalence, communication and past use: understanding what influences women's intentions to use contraceptives

Unintended pregnancy among women in the 18-30 age group is a public health concern. The Extended Parallel Process Model (EPPM) provides a framework for exploring how women's perceptions of threat, efficacy, and fear influence intentions to use contraceptives. Past use and communication with best friends and partners were also considered. A telephone survey of 18-30-year-old women (N = 599) was completed. After univariate and bivariate analyses were conducted, the variables were entered into a hierarchal, multi-variate linear regression with three steps consistent with the EPPM to predict behavioral intention. The first step included the demographic variables of relationship status and income. The constructs for the EPPM were entered into step 2. Step 3 contained the fear measure. The model for the third step was significant, F(10,471) = 36.40, p < 0.001 and the variance explained by this complete model was 0.42. Results suggest that perceived severity of the consequences of an unintended pregnancy (p < 0.01), communication with friends (p < 0.01) and last sexual partner (p < 0.05), relationship status (p < 0.01), and past use (p < 0.001) were associated with women's intentions to use contraceptives. A woman's perception of the severity was related to her intention to use contraceptives. Half of the women (50.3%) reported ambivalence about the severity of an unintended pregnancy. In our study, talking with their last sexual partner had a positive effect on intentions to use contraceptives, while talking with friends influenced intentions in a negative direction. These results reconfirm the need for public health practitioners and health care providers to consider level of ambivalence toward unintended pregnancy, communication with partner, and relationship status when trying to improve women's contraceptive behaviors. Implications for effective communication interventions are discussed.     

Effects of cannabis on eyewitness memory: A field study

Eyewitnesses to crimes are regularly under the influence of drugs, such as cannabis. Yet there is very little research on how the use of cannabis affects eyewitness memory. In the present study, we assessed the effects of cannabis on eyewitness recall and lineup identification performance in a field setting. One hundred twenty visitors of coffee shops in Amsterdam viewed a videotaped criminal event, were interviewed about the event, and viewed a target‐present or target‐absent lineup. Witnesses under the influence of cannabis remembered significantly fewer correct details about the witnessed event than did sober witnesses, with no difference in incorrect recall. Cannabis use was not significantly associated with lineup identification performance, but intoxicated witnesses were significantly better at judging whether their lineup identification was accurate. Theoretical and practical implications of the findings are discussed.     

Exploring the role,needs and challenges of relatives of mothers with HIV or HIV and psychosis: A qualitative study

This study explored types and nature of supports by relatives of mothers living with HIV and psychosis in comparison to mothers with HIV only. Interview data on their experiences of their roles, needs and challenges were collected from 33 relatives on mothers with HIV and psychosis (n=12, females=10, blacks =12, age ranges 21 to 62) and those with HIV only (n=21, females=16, blacks =21, age ranges 18 to 63). The data were thematically analysed utilizing Atlas.ti. The results showed that relatives in both groups provided a variety of supporting roles. Important challenges were experiencing the negative consequences of especially HIV in combination with psychosis in their lives and dealing with the caregiving responsibilities without having enough information. Important strengths included utilizing support networks and remaining hopeful. Support needs for carers of mothers living with HIV related psychosis or HIV only, can be enhanced with increasing social and material resources at the community level. Supporting needs can be addressed by empowering communities through psycho-education.     

Is There Savings for Pavlovian Fear Conditioning after Neurotoxic Basolateral Amygdala Lesions in Rats?

Considerable evidence indicates an important role for amygdaloid nuclei in both the acquisition and expression of Pavlovian fear conditioning. Recent reports from my laboratory have focused on the impact of neurotoxic lesions of the basolateral complex of the amygdala (BLA) on conditional freezing behavior in rats. In these studies, I have observed severe effects of posttraining BLA lesions on the expression of conditional freezing even after extensive presurgical overtraining (25-75 trials). Moreover, I have found no evidence for sparing of fear memory (i.e., savings) in these rats when I assess their rate of reacquisition relative to BLA rats receiving minimal training (1 trial). In these experiments, freezing behavior was assessed using a conventional time-sampling procedure and expressed as a response probability. Although this measure is well established in the literature, it is conceivable that it is not sensitive to spared memory in rats with BLA lesions. To address this issue, I present a more detailed analysis of freezing behavior that quantifies latency to freeze, the number of freezing bouts, the duration of freezing bouts, and the probability distribution of bout lengths. I also include control data from untrained (no-shock) rats. Consistent with my earlier reports, I find no evidence of savings of fear memory in rats with neurotoxic BLA lesions using several measures of freezing behavior. These results reiterate the conclusion that fear memory, as it is expressed in freezing behavior, requires neurons in the BLA.     

Something in the way we move: Motion dynamics, not perceived sex, influence head movements in conversation

During conversation, women tend to nod their heads more frequently and more vigorously than men. An individual speaking with a woman tends to nod his or her head more than when speaking with a man. Is this due to social expectation or due to coupled motion dynamics between the speakers? We present a novel methodology that allows us to randomly assign apparent identity during free conversation in a video-conference, thereby dissociating apparent sex from motion dynamics. The method uses motion-tracked synthesized avatars that are accepted by naive participants as being live video. We find that 1) motion dynamics affect head movements but that apparent sex does not; 2) judgments of sex are driven almost entirely by appearance; and 3) ratings of masculinity and femininity rely on a combination of both appearance and dynamics. Together, these findings are consistent with the hypothesis of separate perceptual streams for appearance and biological motion. In addition, our results are consistent with a view that head movements in conversation form a low level perception and action system that can operate independently from top-down social expectations.     

Growing Up Wired: Social Networking Sites and Adolescent Psychosocial Development

Since the advent of social networking site (SNS) technologies, adolescents’ use of these technologies has expanded and is now a primary way of communicating with and acquiring information about others in their social network. Overall, adolescents and young adults’ stated motivations for using SNSs are quite similar to more traditional forms of communication—to stay in touch with friends, make plans, get to know people better, and present oneself to others. We begin with a summary of theories that describe the role of SNSs in adolescents’ interpersonal relationships, as well as common methodologies used in this field of research thus far. Then, with the social changes that occur throughout adolescence as a backdrop, we address the ways in which SNSs intersect with key tasks of adolescent psychosocial development, specifically peer affiliation and friendship quality, as well as identity development. Evidence suggests that SNSs differentially relate to adolescents’ social connectivity and identity development, with sociability, self-esteem, and nature of SNS feedback as important potential moderators. We synthesize current findings, highlight unanswered questions, and recommend both methodological and theoretical directions for future research.