Deficits in trace cued fear conditioning in galanin-treated rats and galanin-overexpressing transgenic mice

Galanin inhibits the release of several neurotransmitters and produces performance deficits in a variety of spatial and aversive learning and memory tasks. The experiments in this study investigated the role galanin has in emotional learning and memory using a standard delay cued and contextual fear conditioning task. Rats were administered galanin into the lateral ventricles before training, and scored for freezing behavior in the same context and in a novel context with and without an auditory cue (CS) that had been paired previously with an aversive stimulus (US). Galanin-overexpressing transgenic mice were tested in an identical behavioral protocol. The galanin-administered rats and the transgenic mice were not significantly different from their respective controls on this task. A more challenging trace cued and contextual fear conditioning procedure was administered to separate groups of galanin-treated rats and galanin-overexpressing transgenic mice. Subjects were trained with the same CS and US, however, a 2.5-sec delay was inserted between CS offset and US onset. Following the trace conditioning, rats administered galanin and mice overexpressing galanin both exhibited significantly less freezing to the CS in the novel context as compared with their control groups. These results indicate that the observed disruption of cued fear conditioning was specific to the more difficult trace conditioning task. These findings are the first demonstration that galanin impairs performance on an emotional memory task and support the hypothesis that galanin-induced deficits are specific to more difficult cognitive tasks.     

Motor vehicle accident trauma exposure: Personality profiles associated with posttraumatic diagnoses

Abstract

Personality profiles associated with diagnostically distinct posttraumatic responses were examined. Profiles were compared between three groups defined on the basis of posttraumatic diagnosis following motor vehicle accident (MVA) trauma exposure. The diagnostic groups were: Posttraumatic Stress Disorder (PTSD), Acute Stress Disorder (ASD) without progression to PTSD, and subclinical responses. Participants were male and female community volunteers aged 18 to 77 (N = 83) who had all been exposed to an MVA meeting the DSM-IV diagnostic criteria for a traumatic event. The Personality Assessment Inventory (Morey, 1991) was used to assess psychological variables in the framework of posttraumatic diagnostic groups. The PTSD group scored significantly higher than the ASD and subclinical groups on scales assessing somatic complaints, anxiety, anxiety related disorders, depression, non-psychotic symptoms of schizophrenia, and negative relationships. The profile of the ASD group was characterized by self report of greater interpersonal warmth and a trend for greater egocentricity than the PTSD group. There were no significant differences in the personality profiles of the ASD and subclinical groups. The role of personality factors in posttraumatic adjustment is discussed in the context of previous literature.     

Exploring the relation between visual mental imagery and affect in the daily life of previously depressed and never depressed individuals

Previously depressed individuals experience disturbances in affect. Affective disturbances may be related to visual mental imagery, given that imagery-based processing of emotional stimuli causes stronger affective responses than verbal processing in experimental laboratory studies. However, the role of imagery-based processing in everyday life is unknown. This study assessed mental imagery in the daily life of previously and never depressed individuals. Higher levels of visual mental imagery was hypothesised to be associated with more affective reactivity to both negatively and positively valenced mental representations.

This study was the first to explore mental imagery in daily life using experience sampling methodology. Previously depressed (n?=?10) and matched never depressed (n?=?11) individuals participated in this study. Momentary affect and imagery-based processing were assessed using the “Imagine your mood” smartphone application. Participants recorded on average 136 momentary reports over a period of 8 weeks.

The expected association between visual mental imagery and affective reactivity was not found. Unexpectedly, in both previously and never depressed individuals, higher levels of imagery-based processing of mental representations in daily life were significantly associated with better momentary mood and more positive affect, regardless of valence.

The causality of effects remains to be examined in future studies.     

Sample size in psychological research over the past 30 years

The American Psychological Association (APA) Task Force on Statistical Inference was formed in 1996 in response to a growing body of research demonstrating methodological issues that threatened the credibility of psychological research, and made recommendations to address them. One issue was the small, even dramatically inadequate, size of samples used in studies published by leading journals. The present study assessed the progress made since the Task Force's final report in 1999. Sample sizes reported in four leading APA journals in 1955, 1977, 1995, and 2006 were compared using nonparametric statistics, while data from the last two waves were fit to a hierarchical generalized linear growth model for more in-depth analysis. Overall, results indicate that the recommendations for increasing sample sizes have not been integrated in core psychological research, although results slightly vary by field. This and other implications are discussed in the context of current methodological critique and practice.     

Fishing for happiness: the effects of generating positive imagery on mood and behaviour

Experimental evidence using picture-word cues has shown that generating mental imagery has a causal impact on emotion, at least for images prompted by negative or benign stimuli. It remains unclear whether this finding extends to overtly positive stimuli and whether generating positive imagery can increase positive affect in people with dysphoria. Dysphoric participants were assigned to one of three conditions, and given instructions to generate mental images in response to picture-word cues which were either positive, negative or mixed (control) in valence. Results showed that the positive picture-word condition increased positive affect more than the control and negative conditions. Participants in the positive condition also demonstrated enhanced performance on a behavioural task compared to the two other conditions. Compared to participants in the negative condition, participants in the positive condition provided more positive responses on a homophone task administered after 24h to assess the durability of effects. These findings suggest that a positive picture-word task used to evoke mental imagery leads to improvements in positive mood, with transfer to later performance. Understanding the mechanisms underlying mood change in dysphoria may hold implications for both theory and treatment development.     

The cost of lower self-esteem: testing a self- and social-bonds model of health

The authors draw upon social, personality, and health psychology to propose and test a self-and-social-bonds model of health. The model contends that lower self-esteem predicts health problems and that poor-quality social bonds explain this association. In Study 1, lower self-esteem prospectively predicted reports of health problems 2 months later, and this association was explained by subjective reports of poor social bonds. Study 2 replicated the results of Study 1 but used a longitudinal design with 6 waves of data collection, assessed self-reports of concrete health-related behaviors (i.e., number of visits to the doctor and classes missed due to illness), and measured both subjective and objective indicators of quality of social bonds (i.e., interpersonal stress and number of friends). In addition, Study 2 showed that poor-quality social bonds predicted acute drops in self-esteem over time, which in turn predicted acute decreases in quality of social bonds and, consequently, acute increases in health problems. In both studies, alternative explanations to the model were tested.     

Occurrence of imagery and its link with early memories in agoraphobia

Recent cognitive models suggest that mental imagery can help us understand the maintenance of anxiety disorders (e.g., de Silva, 1986; Hackmann, Surawy, & Clark, 1998). However, imagery is relatively unexplored within agoraphobia. Such images are also thought to be useful in uncovering memories that occurred around the onset of a disorder (Hackmann, Clark, & McManus, 2000). A total of 20 patients with agoraphobia and 20 matched controls took part in this investigation. Participants described any recurrent images they experienced in agoraphobic situations, and also any associated memories. All patients with agoraphobia (but no control participants) reported having distinct recurrent images in "agoraphobic situations". Most images involved several sensory modalities and in the majority of cases appeared to be linked with unpleasant memories of events experienced many years previously. While these exploratory findings require replication, potential treatment implications are discussed.     

Putting the partner within reach: a dyadic perspective on felt security in close relationships

The authors argue that felt insecurity in a partner's positive regard and caring stems from a specifically dyadic perception--the perception that a partner is out of one's league. A cross-sectional sample of dating couples revealed that people with low self-esteem feel inferior to their partner and that such feelings of relative inferiority undermine felt security in the partner's regard. Three experiments examined the consequences of reducing such perceived discrepancies by pointing to either strengths in the self or flaws in the partner. Low, but not high, self-esteem participants reacted to new strengths in the self or faults in the partner by reporting greater felt security in their specific partner's positive regard and commitment and more positive, general feelings about their own interpersonal worth. Thus, putting the partner more within the psychological grasp of low self-esteem people may effectively increase felt security in the partner's regard.     

Feminism and Couple Finance: Power as a Mediator Between Financial Processes and Relationship Outcomes

Sex Roles - Feminism is rarely used as a theoretical framework for couple finance research. The purposes of the present paper are (a) to discuss couple finance research in the context of feminism...     

The physics of optimal decision making: a formal analysis of models of performance in two-alternative forced-choice tasks

In this article, the authors consider optimal decision making in two-alternative forced-choice (TAFC) tasks. They begin by analyzing 6 models of TAFC decision making and show that all but one can be reduced to the drift diffusion model, implementing the statistically optimal algorithm (most accurate for a given speed or fastest for a given accuracy). They prove further that there is always an optimal trade-off between speed and accuracy that maximizes various reward functions, including reward rate (percentage of correct responses per unit time), as well as several other objective functions, including ones weighted for accuracy. They use these findings to address empirical data and make novel predictions about performance under optimality.