Color of computer display frame in work performance, mood, and physiological response

The effects of the color of a personal computer screen on work performance, psychological mood, and autonomic response were investigated. 24 subjects were asked to perform visual tasks presented on the computer display. Three types of computer monitor, which were colored red, blue, or beige, were employed to present visual cognitive tasks. The mood measure, the Japanese Stress Arousal Check List, and heart rate measurement were administered before and after work on each color of computer monitor. Analysis of a low-demand task (Exp. 1) showed that the red computer monitor reduced visual task performance compared to that with the blue, while the blue monitor decreased visual task performance on a high-demand task (Exp. 2). The color of the monitor did not affect mood or heart rate. Based on these findings, the effect of the color of environmental cues on work was discussed.     

Fluctuations of answer and confidence rating in a general-knowledge problem task: Is confidence rating a result of direct memory-relevant output monitoring?

In order to examine whether confidence rating is a result of direct memory-relevant output monitoring, a general-knowledge test was used. A question set was answered in experimental session 1, and the same question set was employed in session 2. Subjects chose one answer from two alternatives. No significant difference in answer accuracy was found between sessions, which suggests that identical information processing was carried out, and that any difference between sessions was based on probabilistic fluctuation. The major results were as follows: (a) In both sessions, answer accuracy was an increasing function of confidence. (b) Answer-change rate (rate of different answers to the same question between sessions) decreased monotonically with confidence. (c) The distributions of confidence rating in session 2, conditional on the rating in session 1, were nearly identical in no-answer-change and answer-change cases. These results suggest that confidence rating is not a result of monitoring memory-relevant output itself but an estimation of possibility of answer fluctuation.     

Differential effects of physical and psychological stressors on immune functions of rats

To study the effects of different types or durations of stressors on immune functions, male Fischer rats were exposed to chronic physical (electric foot shock) or psychological (non-foot shock) stress induced in the communication box. Superoxide production by alveolar macrophages (AMs), mitogen-induced splenic lymphocyte proliferation, and splenic natural killer (NK) cell cytolysis were examined in vitro. Repeated exposure to physical stress suppressed superoxide production by AMs (-58%, p<0.05 for opsonized zymosan (OZ) and -51%, p<0.05 for phorbol 12-myristate 13-acetate (PMA)), although psychological stress suppressed superoxide production after 24 h of repeated exposures (-40%, p<0.05 for OZ and -47%, p<0.05 for PMA). Acute suppression of the blastic response of splenic lymphocytes was only found in the physical stress group (p<0.05), although the chronic effects were only found in the psychological stress group (p<0.05). NK cell activity was suppressed immediately after the acute physical stress (-30%, p<0.05), but no effects were found in the psychological stress group. These results underline the importance of distinguishing between physical versus psychological stressors when examining the effects of stress on immune functions.     

Observation of Cu nanometre scale clusters formed in Fe85Si2B8P4Cu1 nanocrystalline soft magnetic alloy by a spherical aberration-corrected TEM/STEM

Microstructure of a nanocrystalline soft magnetic Fe₈₅Si₂B₈P₄Cu₁ alloy (NANOMET^®) was investigated by the state of the art spherical aberration-corrected TEM/STEM. Observation by TEM shows that the microstructure of NANOMET^® heat treated at 738 K for 600 s which exhibits the optimum soft magnetic properties has homogeneously distributed bcc-Fe nanocrystallites with the average grain size of 30 nm embedded in an amorphous matrix. Elemental mappings indicate that P is excluded from bcc-Fe grains and enriched outside the grains, which causes to retard the grain growth of bcc-Fe crystallites. The aberration-corrected STEM-EDS analysis with the ultrafine electron probe successfully proved that Cu atoms form nanometre scale clusters inside and/or outside the bcc-Fe nanocrystallites.     

Band-edge states in ultrasmall silicon quantum boxes: Calculations of electronic states and oscillator strengths

Band-edge states and oscillator strengths in four configurations of ultrasmall Si quantum boxes (QBs) with (100) planes saturated by H have been calculated using the extended Hückel-type non-orthogonal tight-binding method. It is found that, while the valence-band edge states are always bulk like, both bulk-like and surface-like states occur at the conduction-band (CB) edge, depending on the atom configuration of the QB studied. An analysis shows that the surface-like CB edge states are caused by an interhydride interaction between trihydride units on the hydrogenated QB surface and there is significant correlation of oscillator strength with the CB edge states.     

Two modes of confidence rating: An effect of episodic information of participant's own past responses in a repeated-question paradigm

Abstract: General knowledge questions with two answer alternatives were employed in experimental session 1; in session 2, the same questions were presented together with participants' own session-1 responses. In order to examine whether or not the episodic information of participant's own responses would suppress standard confidence-rating mode in session 2, rates of answer- and confidence-changes between sessions were analyzed. In session 2, participants were able to change the confidence value to another, if they thought the initial value inadequate. They then had a chance to change the answer to the other and rated their confidence in the new answer. The major results were as follows: (a) Between-session answer change rate was very low; (b) Between-session answer change rate was not a monotonic decreasing function of confidence; (c) However, the rate depended on confidence change from session 1 to before-answer-change rating. These results clearly contrasted with a previous study ( Saito, 1998 ) in which episodic information of participant's own session 1 answers and confidence values was not presented. It was argued that the episodic information triggered another mode of confidence rating or a decision inertia effect.     

Mediating effect of environmental rewards on the relation between goal-directed behaviour and anhedonia

Depression can be explained by certain behavioural patterns, especially low levels of environmental rewards; it is generally accompanied by infrequent goal-directed behaviour, increased depressed mood, and anhedonia. However, no research has statistically examined the mediating effect of environmental rewards on the relation between goal-directed behaviour and the symptoms of depressed mood or anhedonia. This study sought to determine whether such a mediating effect of environmental rewards is present in cross-sectional study. The participants included 101 patients diagnosed with major depressive disorders. Data were collected through three questionnaires measuring depression and behavioural patterns that maintain depression: the Center for Epidemiologic Studies Depression Scale (CES-D), the Environmental Reward Observation Scale (EROS), and the Behavioral Activation for Depression Scale—Short Form (BADS-SF). Mediation analysis was conducted using depressed mood and anhedonia as dependent variables, environmental rewards as the mediating variable, and goal-directed behaviour as the independent variable. Environmental rewards significantly mediated the relationship between goal-directed behaviour and anhedonia but not that between goal-directed behaviour and depressed mood. No significant relationships were found among depressed mood, goal-directed behaviour and environmental rewards. From these results, we conclude that low levels of environmental rewards accompanied by infrequent goal-directed behaviour can lead to increased anhedonia but not depressed mood.

     

Same-different reaction times studied with a flash masking technique

The reaction times (RT) needed to report whether letters were the same or different were measured using a very long exposure of the target and a very brief exposure of a flash mask. Two letters were presented simultaneously in Experiment 1. No effect of response category (same vs. different) was found, although a clear-cut luminance-dependent masking effect was present. Letter number was manipulated in Experiment 2. A three-way interaction was found among response category, number of letters, and stimulus onset asynchrony (SOA). The more difficult task produced longer RTs for “different” judgments than for “same” judgments, particularly at intermediate SOAs. These data are compared with information processing models of perception.     

Dynamics of Interpersonal Political Environment and Party Identification: Longitudinal Studies of Voting in Japan and New Zealand

The dynamical systems theory of groups claims that interpersonal political environment and party identification are dynamically interrelated to provide heuristics under uncertainty. Panel data over the course of a year examined the longitudinal dynamics between social networks, social identifications, and voting behavior among a national sample of registered voters in Japan and a regional sample in Wellington, New Zealand. Respondents with more stable party identification had greater stability in the political preferences of their interpersonal network in both countries; moreover, stability in party identification was predicted by interpersonal political environment and older age in both countries. Stability of party identification predicted voting consistency in both countries, whereas stability of interpersonal political environment made an independent contribution to voting consistency in Japan only. There were cultural differences in levels of interpersonal political environment stability, but the amount of political discussion and ideological stability did not make independent contributions to any of the three main variables. Results provided support for the dynamical systems theory of groups.