Interactive effect of long-term mental stress and cardiac stress reactivity on carotid intima-media thickness: the Cardiovascular Risk in Young Finns study

The present study examined the interaction between vital exhaustion and cardiac reactivity and recovery on preclinical atherosclerosis assessed by carotid intima-media thickness (IMT) in young men and women. We measured heart rate (HR), respiratory sinus arrhythmia (RSA), and pre-ejection period (PEP) in response to mental arithmetic and speech tasks. Vital exhaustion and carotid IMT were also measured. Significant associations were observed for men aged 28-37 years, but not for men aged 22-25 years, nor for women in these age groups. It was shown that, among highly exhausted men in the older age group, lower HR reactivity was related to greater IMT. Our results also imply that, among non-exhausted men in this age group, slow HR and RSA recovery after acute stress predicted higher IMT. These results suggest that long-term stress as assessed by vital exhaustion is a risk only if it has resulted in ineffective cardiac stress reactivity. Autonomic imbalance resulting from chronic stress may be the common mechanism linking vital exhaustion and cardiac responsiveness to an increased risk of atherosclerosis.     

Socio-cognitive conflict, emotions and complexity of thought in real-life morality

A new taxonomy of real-life dilemmas was tested in two studies. In Study 1, 35 respondents assessed six types of real-life dilemmas in terms of socio-cognitive conflict. Support was found for a classification of dilemmas into three levels of socio-cognitive conflict. In Study 2, 191 young women responded to measures of social perspective-taking and emotional empathy and reported a real-life moral dilemma as well as their feelings while making decisions about it. The dilemmas were classified into personal and impersonal and into three levels of socio-cognitive conflict. Dependent variables were the integrative complexity of the arguments and the reported feelings (sympathy, upset, and remorse). Dispositional empathy and perspective taking predicted level of socio-cognitive conflict and feelings of sympathy but not integrative complexity. Personal dilemmas aroused more feelings of upset than did impersonal ones. Low socio-cognitive conflict dilemmas evoked less complex thinking and less intensive feelings of upset and sympathy than did moderate and high socio-cognitive conflict dilemmas.     

Activation and survival of immature neurons in the dentate gyrus with spatial memory is dependent on time of exposure to spatial learning and age of cells at examination

Neurogenesis continues to occur throughout life in the dentate gyrus of the hippocampus and may be related to hippocampus-dependent learning. We have recently reported that there is an enhancement of neurogenesis in the hippocampus only when BrdU is administered 6 days prior to starting spatial training but not when training started either 1 day or 11 days following BrdU administration. In that study, all rats were perfused on day 16 after BrdU injection in order to compare cells of the same age (i.e. 16 day old cells) and thus the survival time after learning was different between groups. This study was designed to address whether the amount of time that passed following training could also contribute to the effects of spatial learning on hippocampal neurogenesis and whether there was differential new neuron activation in response to spatial learning that depended on the age of new cells at the time of spatial learning. Here we tested whether a survival period of 5 days following spatial learning at either 1-5, 6-10 or 11-15 days following BrdU administration would alter cell survival and/or activation of new neurons. Our results indicate that 5 days after training in the Morris water task cell survival is unaltered by training on days 1-5, increased by training at days 6-10 and decreased when training occurs on days 11-15. Furthermore spatial learners trained on days 6-10 or 11-15 show greater activation of new neurons compared to cue-trained rats during a probe trial 5 days after training. In addition, rats trained on the spatial task on days 11-15 had a greater number of activated new neurons compared to rats trained on the spatial task on days 6-10. These results suggest there is a gradual removal of older BrdU-labeled new neurons following spatial learning perhaps due to a competitive interaction with a population of younger BrdU-labeled new neurons.     

Co-occurrence of personality disorders with mood, anxiety, and substance use disorders in a young adult population

The purpose of this study was to determine the co-occurrence of DSM- III-R personality disorders (PDs) with mood, anxiety, and substance use disorders in a young adult population. The members of the Northern Finland 1966 Birth Cohort Project, living in the city of Oulu with an age of 31 years (N = 1,609) were invited to participate in a two-phase field study. The SCID I and II were used as diagnostic instruments. One hundred and seventy-seven out of 321 interviewed subjects met the criteria for mood, anxiety, or substance use disorders. Altogether 72 (41%) of the subjects with an Axis I disorder met the criteria for at least one PD. The weighted co-occurrence rate of any PD varied from 28% for mood disorders to 47% for anxiety disorders. PDs, especially those in Cluster C, are highly associated with Axis I psychiatric disorders in population.     

Systemic and local administration of estradiol into the prefrontal cortex or hippocampus differentially alters working memory

The influence of estradiol on learning and memory is dependent on a number of factors. The effects of physiological levels of estradiol on the acquisition of a spatial working memory task mediated by the prefrontal cortex (PFC) and the hippocampus were examined in Experiment 1. Ovariectomized Long-Evans rats received daily injections of estradiol or vehicle were tested on the win-shift version of the radial arm maze. A high dose of estradiol benzoate (5 microg) enhanced acquisition of the task, whereas a low dose of estradiol (0.3 microg) increased the number of errors committed over 17 days of testing. Experiment 2 was conducted to examine site-specific influences of estradiol on spatial working memory in well-trained rats. Saline and estradiol cyclodextrin (0.1 and 0.9 microg) were infused into the prelimbic region of the PFC or dorsal hippocampus 40 min prior to testing on the win-shift task. Infusions of estradiol into both brain areas attenuated saline-infusion disruptions in working memory. Specifically, the higher dose of estradiol facilitated working memory when infused into the PFC, whereas the lower dose of estradiol facilitated performance when infused into the dorsal hippocampus. Moreover, working memory was significantly impaired 24 h after infusions of estradiol into the dorsal hippocampus but not the PFC. These data provide further evidence for the notion that estradiol can dose-dependently alter memory processes and suggest that facilitation or disruptions of working memory by estradiol are site- and time-specific.     

Suboptimal exposure to facial expressions when viewing video messages from a small screen: effects on emotion, attention, and memory

The authors examined the effects of suboptimally presented facial expressions on emotional and attentional responses and memory among 39 young adults viewing video (business news) messages from a small screen. Facial electromyography (EMG) and respiratory sinus arrhythmia were used as physiological measures of emotion and attention, respectively. Several congruency priming effects were found. In particular, happy facial primes prompted increased (a) pleasure ratings, (b) orbicularis oculi EMG activity, (c) perceived trustworthiness, and (d) recognition memory for video messages with a positive emotional tone. Emotional and other responses to video messages presented on a small screen can be modified with suboptimal affective primes, but even small differences in the emotional tone of the messages should be allowed for.     

Smoothing enhances the detection of common structure from multiple time series

The effects of smoothing (i.e., temporal averaging) on the detection of intraindividual interdependency from between-subjects aggregated (i.e., multiple) bivariate time series were examined. A simple moving average smoother was applied to different types of simulated processes that included error. The results indicated that smoothing facilitates the detection of common intraindividual structure from multiple time series. The efficacy of smoothing was dependent on the characteristics of the underlying process. It is suggested that smoothing increases the efficiency of the detection of common structure by increasing the signal-to-noise ratio (i.e., temporal reliability) of the time series. The issue and application of smoothing is further discussed in terms of signal extraction and classical test theory.