Ruminative and reflective forms of self-focus: Their relationships with interpersonal skills and emotional reactivity under interpersonal stress

Self-focus can be divided into adaptive and maladaptive aspects, that is, self-reflection and self-rumination respectively. This study explores how these distinctive forms of self-focus are associated with interpersonal skills required for beginning and maintaining social relationships, and with negative emotional regulation when one experiences interpersonal problems. A survey of 150 undergraduates (Study 1) indicated contrasting cross-sectional associations between self-reflection and self-rumination and interpersonal skills; self-rumination is associated with perceived impaired interpersonal skills, whereas self-reflection is associated with the improved skills. In Study 2, using a four-wave longitudinal design, we investigated the buffering effects of self-rumination and self-reflection on negative emotional reactivity to interpersonal conflicts. Analysis of multilevel models indicated that self-rumination predicts a greater increase in negative affect after one experiences negative interpersonal events, whereas self-reflection had no such effects on the negative affect. These results suggest that self-rumination is associated with perceived impaired interpersonal skills, which could delay problem solving and exacerbate the effect of interpersonal problems, thereby leading to dysphoria. In contrast, self-reflection might contribute to the maintenance of relationships in usual or stable conditions but does not aid emotion regulation or problem solving in difficult or negative situations such as when one experiences interpersonal problems.     

Evidence for a fixed capacity limit in attending multiple locations

A classic question concerns whether humans can attend multiple locations or objects at once. Although it is generally agreed that the answer to this question is “yes,” the limits on this ability are subject to extensive debate. According to one view, attentional resources can be flexibly allocated to a variable number of locations, with an inverse relationship between the number of selected locations and the quality of information processing at each location. Alternatively, these resources might be quantized in a “discrete” fashion that enables concurrent access to a small number of locations. Here, we report a series of experiments comparing these alternatives. In each experiment, we cued participants to attend a variable number of spatial locations and asked them to report the orientation of a single, briefly presented target. In all experiments, participants’ orientation report errors were well-described by a model that assumes a fixed upper limit in the number of locations that can be attended. Conversely, report errors were poorly described by a flexible-resource model that assumes no fixed limit on the number of locations that can be attended. Critically, we showed that these discrete limits were predicted by cue-evoked neural activity elicited before the onset of the target array, suggesting that performance was limited by selection processes that began prior to subsequent encoding and memory storage. Together, these findings constitute novel evidence supporting the hypothesis that human observers can attend only a small number of discrete locations at an instant.     

Irradiation-induced amorphization of graphite: A dislocation accumulation model

We present a kinetic model to explain irradiation-induced phenomena in graphite up to a high dose of amorphization. We attribute the origin of amorphization to the accumulation of dislocation dipoles instead of a disordered region assumed in a previous model by Niwase. Calculated results for the change in a sample dimension up to amorphization and the Raman intensity ratio in a low-damage range compare favourably with the experimental results, revealing the existence of a barrier inhibiting the mutual annihilation of an interstitial and a vacancy.     

Using transcranial direct-current stimulation (tDCS) to understand cognitive processing

Noninvasive brain stimulation methods are becoming increasingly common tools in the kit of the cognitive scientist. In particular, transcranial direct-current stimulation (tDCS) is showing great promise as a tool to causally manipulate the brain and understand how information is processed. The popularity of this method of brain stimulation is based on the fact that it is safe, inexpensive, its effects are long lasting, and you can increase the likelihood that neurons will fire near one electrode and decrease the likelihood that neurons will fire near another. However, this method of manipulating the brain to draw causal inferences is not without complication. Because tDCS methods continue to be refined and are not yet standardized, there are reports in the literature that show some striking inconsistencies. Primary among the complications of the technique is that the tDCS method uses two or more electrodes to pass current and all of these electrodes will have effects on the tissue underneath them. In this tutorial, we will share what we have learned about using tDCS to manipulate how the brain perceives, attends, remembers, and responds to information from our environment. Our goal is to provide a starting point for new users of tDCS and spur discussion of the standardization of methods to enhance replicability.     

Well-Being and Generalized Anxiety in Japanese Undergraduates: A Prospective Cohort Study

Psychological well-being is thought to protect against common mental health problems. This study investigated the buffering effects of psychological well-being on the relationships between cognitive vulnerabilities (fear of anxiety and negative beliefs about worry) and GAD symptoms among 297 Japanese undergraduates (female = 62%, age = 18.91 ± 1.61) in a two-wave prospective cohort study. Participants completed the Generalized Anxiety Disorder Questionnaire for DSM-IV, Center for Epidemiologic Studies Depression Scale, anxiety control subscale of Affective Control Scale, negative belief about worry subscale of Meta-Cognitions Questionnaire, and Nishida’s psychological well-being scale. A moderated regression analysis tested the buffering effect of psychological well-being sub-dimensions on the relationship between cognitive vulnerabilities and generalized anxiety symptoms. Fear of anxiety (β = 0.16, p < 0.01) and negative beliefs about worry (β = 0.16, p < 0.01) at baseline predicted generalized anxiety at follow-up, after controlling for baseline symptoms, and three interaction terms significantly predicted generalized anxiety symptoms. Purpose in life and autonomy buffered the negative relationship between cognitive vulnerabilities and generalized anxiety symptoms. Contrary to the hypothesized relationship, positive relationships with others at baseline facilitated a positive relationship between fear of anxiety and generalized anxiety symptoms. Those results suggested that enhanced Purpose in life and Autonomy dimension of Psychological well-being may be useful in preventing GAD, while the enhanced positive relationship with others dimension of Psychological well-being may facilitate generalized anxiety, as a function of fear of anxiety. In a primary prevention setting, it may be useful to consider the dimensions of Psychological well-being.     

Velocity-dependent EMG activity of masseter and sternocleidomastoideus muscles during a ballistic arm thrusting movement

Two experiments were conducted to investigate the functional relationship between the general somatic motor function and the oral motor function. In Experiment 1, we analyzed the relationship between the amount of masseter muscle (MSS) activity and the velocity of a ballistic, 'karate-do' arm thrusting movement (ThrMov). ThrMov velocity was measured from video images taken with a high-speed CCD camera at a frequency of 500Hz. EMGs of MSS and sternocleidomastoideus (SCM) muscles as well as other related muscles were recorded simultaneously with video images in 6 varsity 'karate-do' athletes. Pearson's correlation coefficients were calculated between EMG amplitude and movement velocity. EMG activity of MSS as well as the other muscles increased as a function of ThrMov velocity in all participants, as evidenced by highly significant (p<.01) correlation coefficients, ranging from .64 to .87 (mean: .75). MSS EMG activity attained during ThrMovs performed at maximum velocity ranged between 14.6% and 113.8% of this muscle's MVC (45.7+/-39.3% MVC, mean+/-SD). SCM was also strongly active and closely associated with MSS. Besides changes in amount of EMG activity, it was further found that R-MSS EMG onset progressively shifted to the earlier phase of the ThrMov as ThrMov velocity increased. EMG onset time of R-MSS as well as R- and L-SCMs was negatively correlated with ThrMov velocity; when performed at maximum velocity MSS activation preceded the start of ThrMov by more than 100ms, whereas MSS was recruited last at approximately 150ms after the start of ThrMov when performed at moderate speed ( approximately 50% of maximum). In Experiment 2, the effects of head movement relative to the trunk on R-MSS and SCMs EMG activity were tested in both gazing and sidelong glancing conditions. A much smaller head rotation relative to the trunk was necessary during the ThrMov in the sidelong glancing condition compared to the gazing condition. R-MSS EMG activity was affected significantly by the difference between these conditions and decreased by 5.2% MVC in the sidelong glancing condition compared to the gazing condition. In association with the change in requirement for head movement between those conditions, EMG balance between the bilateral SCMs changed substantially. Finally, marked muscle activity during ThrMov was found in the MSS that was not directly involved in performing this movement, indicating a form of 'remote facilitation'.     

Repetitive Thought Impairs Sleep Quality: An Experience Sampling Study

Although previous research has suggested that presleep negative cognitive activities are associated with poor sleep quality, there is little evidence regarding the association between negative thoughts and sleep in real-life settings. The present study used experience sampling and long-term sleep monitoring with actigraphy to investigate the relationships among negative repetitive thought, mood, and sleep problems. During a 1-week sampling period, 43 undergraduate students recorded their thought content and mood eight times a day at semirandom intervals. In addition to these subjective reports, participants wore actigraphs on their wrists in order to measure sleep parameters. Analyses using multilevel modeling showed that repetitive thought in the evening was significantly associated with longer sleep-onset latency, decreased sleep efficiency, and reduced total sleep time. Furthermore, impaired sleep quality was significantly associated with reduced positive affect the next morning, and decreased positive affect was indirectly associated with increased repetitive thought in the evening. These findings suggest the existence of a self-reinforcing cycle involving repetitive thought, mood, and impaired sleep quality, highlighting the importance of cognitive and emotional factors in enhancement and maintenance of good-quality sleep.     

Unraveling the linguistic nature of specific autobiographical memories using a computerized classification algorithm

In the present study, we explored the linguistic nature of specific memories generated with the Autobiographical Memory Test (AMT) by developing a computerized classifier that distinguishes between specific and nonspecific memories. The AMT is regarded as one of the most important assessment tools to study memory dysfunctions (e.g., difficulty recalling the specific details of memories) in psychopathology. In Study 1, we utilized the Japanese corpus data of 12,400 cue-recalled memories tagged with observer-rated specificity. We extracted linguistic features of particular relevance to memory specificity, such as past tense, negation, and adverbial words and phrases pertaining to time and location. On the basis of these features, a support vector machine (SVM) was trained to classify the memories into specific and nonspecific categories, which achieved an area under the curve (AUC) of .92 in a performance test. In Study 2, the trained SVM was tested in terms of its robustness in classifying novel memories (n?= 8,478) that were retrieved in response to cue words that were different from those used in Study 1. The SVM showed an AUC of .89 in classifying the new memories. In Study 3, we extended the binary SVM to a five-class classification of the AMT, which achieved 64%–65% classification accuracy, against the chance level (20%) in the performance tests. Our data suggest that memory specificity can be identified with a relatively small number of words, capturing the universal linguistic features of memory specificity across memories in diverse contents.     

Quantity,not quality: the relationship between fluid intelligence and working memory capacity

A key motivation for understanding capacity in working memory (WM) is its relationship with fluid intelligence. Recent evidence has suggested a two-factor model that distinguishes between the number of representations that can be maintained in WM and the resolution of those representations. To determine how these factors relate to fluid intelligence, we conducted an exploratory factor analysis on multiple number-limited and resolution-limited measures of WM ability. The results strongly supported the two-factor model, with fully orthogonal factors accounting for performance in the number-limited and resolution-limited conditions. Furthermore, the reliable relationship between WM capacity and fluid intelligence was exclusively supported by the number factor (r=.66), whereas the resolution factor made no reliable contribution (r=−.05). Thus, the relationship between WM capacity and standard measures of fluid intelligence is mediated by the number of representations that can be simultaneously maintained in WM, rather than by the precision of those representations.