The influence of the noradrenergic/stress system on perceptual biases for reward.

Previous research has established a role for the norepinephrine (NE)/stress system in individual differences in biases to attend to reward or punishment. Outstanding questions concern its role in the flexibility with which such biases can be changed. The goal of this preregistered study was to examine the role of the NE/stress system in the degree to which biases can be trained along the axis of valence in the direction of reward. Participants genotyped for a common deletion variant of ADRA2b (linked to altered NE availability) experienced either an acute stress induction or a control procedure. Following stress induction, a "bias probe" task was presented before and after training. In the bias probe task, participants made forced choice judgments (happy or angry) on emotional faces with varying degrees of ambiguity. For bias training, participants viewed unambiguously angry faces in a task exploiting visual adaptation effects. The results revealed an overall shift from a slightly positive bias in categorizing faces pretraining to a more positive bias after training. Carriers of the deletion variant overall showed a more positive bias than did the noncarriers. Follow-up analyses showed that pretraining bias was a significant predictor of bias change, with those who showed a more negative bias preadaptation changing more in a positive direction. Critically, this effect was observed under control but not under stress conditions. These results suggest that the NE/stress system plays an important role in influencing trait-like biases as well as short-term changes in the tendency to perceive ambiguous stimuli as being more rewarding than threatening.

Acute psychophysiological stress impairs human associative learning.

Addiction is increasingly discussed asa disorder of associative learning processes, with both operant and classical conditioning contributing to the development of maladaptive habits. Stress has long been known to promote drug taking and relapse and has further been shown to shift behavior from goal-directed actions towards more habitual ones. However, it remains to be investigated how acute stress may influence simple associative learning processes that occur before a habit can be established. In the present study, healthy young adults were exposed to either acute stress or a control condition half an hour before performing simple classical and operant conditioning tasks. Psychophysiological measures confirmed successful stress induction. Results of the operant conditioning task revealed reduced instrumental responding under delayed acute stress that resembled behavioral responses to lower levels of reward. The classical conditioning experiment revealed successful conditioning in both experimental groups; however, explicit knowledge of conditioning as indicated by stimulus ratings differentiated the stress and control groups. These findings suggest that operant and classical conditioning are differentially influenced by the delayed effects of acute stress with important implications for the understanding of how new habitual behaviors are initially established.

Deletion variant in the ADRA2B gene increases coupling between emotional responses at encoding and later retrieval of emotional memories.

A deletion variant of the ADRA2B gene that codes for the α2b adrenoceptor has been linked to greater susceptibility to traumatic memory as well as attentional biases in perceptual encoding of negatively valenced stimuli. The goal of the present study was to examine whether emotional enhancements of memory associated with the ADRA2B deletion variant were predicted by encoding, as indexed by the subjectively perceived emotional salience (i.e., arousal) of events at the time of encoding. Genotyping was performed on 186 healthy young adults who rated positive, negative, and neutral scenes for level of emotional arousal and subsequently performed a surprise recognition memory task 1 week later. Experience of childhood trauma was also measured, as well as additional genetic variations associated with emotional biases and episodic memory. Results showed that subjective arousal was linked to memory accuracy and confidence for ADRA2B deletion carriers but not for non-carriers. Our results suggest that carrying the ADRA2B deletion variant enhances the relationship between arousal at encoding and subsequent memory for moderately arousing events.

Group specific optimisation of fMRI processing steps for child and adult data.

Motion is a major issue in functional magnetic resonance imaging (fMRI) dataseries and causes artifacts or increased overall noise obscuring signals of interest. It is particularly important to be able to control for and correct these artifacts when dealing with child data. We analysed the data from 35 children (4-8 years old) and 13 adults (18-30 years old) during an emotional face paradigm. The children were split into low and high motion groups on the basis of having less or more than an estimated maximal movement of one voxel (3.75 mm) and one degree of rotation in any motion direction between any pair of scans in the run. Several different preprocessing steps were evaluated for their ability to correct for the excess motion using agnostic canonical variates analysis (aCVA) in the NPAIRS (Nonparametric, Prediction, Activation, Influence, Reproducibility, re-Sampling) framework. The adult dataset was reasonably stable whereas the motion-prone child datasets benefited greatly from motion parameter regression (MPR). Motion parameter regression had a strong beneficial impact on all datasets, a result that was largely unaffected by other preprocessing choices; however, motion correction on its own did not have as much impact. The low motion child group subjected to MPR had reproducibility values at par with those of the adult group, but needed almost twice as many subjects to achieve this result, indicating weaker responses in young children. The aCVA showed greater sensitivity to the task response pattern than the mixed effects general linear model (mGLM) in the expected face processing regions, although the mGLM showed more responses in some other areas. This work illustrates that preprocessing choices must be made in a group-specific fashion to optimise fMRI results.

Experiential History as a Tuning Parameter for Attention.

[Peer commentary on "Visual selection: usually fast and automatic; seldom slow and volitional," by J. Theeuwes]. Journal of Cognition. In his current opinion piece, Theeuwes emphasizes the role of selection history as a third source of attentional selection, beyond top-down and bottom-up mechanisms, thus challenging traditional dual-process models of attention. While we agree that selection history impacts the allocation of attention, our own work suggests that this terminology may be too restrictive, and propose the simple term history as a better reflection of the impact of learning on our selection biases. Furthermore, we propose that the role of selection/experiential history on attention may not be as a unique third source of attentional selection, but rather as a tuning parameter, allowing certain categories of item to be endowed with greater task-based or feature-driven salience in a context and history dependent manner. This conceptualization presents an alternative to abandoning dual-process models of attention altogether. Rather, we can reimagine how task-based and feature-driven processes may be controlled by past experience in a dynamic and adaptable system.

A new technique for securing a foley catheter.

We describe a new technique to secure a urethral catheter using a horizontal drain tube stabilizer. This device is reliable, inexpensive, and more comfortable for patients than either adhesive tape or leg straps.

Long-term evaluation of naproxen suspension in juvenile chronic arthritis.

Twenty-six children suffering from juvenile chronic arthritis were entered into a 6-month open evaluation of naproxen suspension. Sixteen patients completed 6-months' treatment, 6 were lost to follow-up and 4 dropped out, 2 because of side-effects (rash, and burning on swallowing the formulation), 1 for lack of efficacy and 1 because of no further need of treatment. Pain severity scores were significantly reduced from admission levels at all monthly follow-up visits and significant overall improvement since the last visit was noted up to third month of treatment, as assessed by doctor and parent/patient. Transient indigestion was reported by 2 patients. No clinically significant trends were noted in any of the laboratory investigations carried out. The results add to the accumulation of data on the use of naproxen in children and underline its long-term efficacy and tolerance.

Empathic joy and the empathy-altruism hypothesis.

Three experiments tested whether empathy evokes egoistic motivation to share vicariously in the victim's joy at improvement (the empathic-joy hypothesis) instead of altruistic motivation to increase the victim's welfare (the empathy-altruism hypothesis). In Experiment 1, Ss induced to feel either low or high empathy for a young woman in need were given a chance to help her. Some believed that if they helped they would receive feedback about her improvement; others did not. In Experiments 2 and 3, Ss induced to feel either low or high empathy were given a choice of getting update information about a needy person's condition. Before choosing, they were told the likelihood of the person's condition having improved--and of their experiencing empathic joy--was 20%, was 50%, or was 80%. Results of none of the experiments patterned as predicted by the empathic-joy hypothesis; instead, results of each were consistent with the empathy-altruism hypothesis.

The diagnostic meaning of "nervous breakdown" among lay populations.

Two studies investigated the nature of nervous breakdown (NB): a mental illness commonly referred to by individuals not professionally related to the field of mental health. The clinical profile of NB was first surveyed among 121 undergraduates using a symptom checklist. Descriptive statistics and analysis of variance indicated NB is a time-limited condition that presents with primarily anxious and depressed features, associated with a series of external precipitating stressors (e.g., interpersonal, employment, and financial losses). Dimensions significantly uncharacteristic of NB included psychoticism, somatization, phobic anxiety, and mania. These results were replicated in a community sample of 189 adults from urban and suburban areas of a large metropolitan city. Respondents held a relatively unitary view of NB: Combined-sample cluster analysis (N = 310) revealed 2 groups with similar symptom profiles that differed primarily with regard to level of distress associated with disorder. Thus, among this population, NB is not an amorphous term for generalized psychiatric disturbance.