A group construal account of drop-in-the-bucket thinking in policy preference and moral judgment

Decisions, both moral and mundane, about saving individuals or resources at risk are often influenced not only by numbers saved and lost, but also by proportions of groups saved and lost. Consider choosing between a program that saves 60 of 240 lives at risk and one that saves 50 of 100. The first option maximizes absolute number saved; the second, proportion saved. In two studies, we show that the influence of proportions on such decisions depends on how items at risk are mentally represented. In particular, we show that proportions have greater influence on people's decisions to the extent that the items at risk are construed as forming groups, as opposed to distinct individuals. Construal was manipulated by means of animated displays in which resources at risk moved either independently (promoting individual construal) or jointly (promoting group construal). Results support the hypothesis that (a) decision makers form mental representations which vary in the degree to which resources at risk are construed as groups versus individuals and (b) construal of resources as groups promotes the influence of proportions on decisions and moral judgments.     

Happy to See Me,Aren’t You,Sally? Signal Detection Analysis of Emotion Detection in Briefly Presented Male and Female Faces

Using signal detection methods, possible effects of emotion type (happy, angry), gender of the stimulus face, and gender of the participant on the detection and response bias of emotion in briefly presented faces were investigated. Fifty-seven participants (28 men, 29 women) viewed 90 briefly presented faces (30 happy, 30 angry, and 30 neutral, each with 15 male and 15 female faces) answering yes if the face was perceived as emotional and no if it was not perceived as emotional. Sensitivity [d', z(hit rate) minus z(false alarm rate)] and response bias (β, likelihood ratio of "signal plus noise" vs. "noise") were measured for each face combination for each presentation time (6.25, 12.50, 18.75, 25.00, 31.25 ms). The d' values were higher for happy than for angry faces and higher for angry-male than for angry-female faces, and there were no effects of gender-of-participant. Results also suggest a greater tendency for participants to judge happy-female faces as emotional, as shown by lower β values for these faces as compared to the other emotion-gender combinations. This happy-female response bias suggests, at least, a partial explanation to happy-superiority effects in studies where performance is only measured as percent correct responses, and, in general, that women are expected to be happy.     

Message sidedness in advertising: the moderating roles of need for cognition and time pressure in persuasion

Persuasion has been extensively researched for decades. Much of this research has focused on different message tactics and their effects on persuasion (e.g., Chang & Chou, 2008; Lafferty, 1999). This research aims to assess whether the persuasion of a specific type of message is influenced by need for cognition (NFC) and time pressure. The 336 undergraduates participated in a 2 (message sidedness: one-sided/two-sided) × 3 (time pressure: low/moderate/high) between-subjects design. Results indicate that two-sided messages tend to elicit more favorable ad attitudes than one-sided messages. As compared with low-NFC individuals, high-NFC individuals are likely to express more favorable ad attitudes, brand attitudes and purchase intention. Moderate time pressure tends to lead to more favorable ad attitudes than low time pressure and high time pressure. In addition, moderate time pressure is likely to elicit more favorable brand attitudes and purchase intentions than high time pressure, but does not elicit more favorable brand attitudes and purchase intentions than low time pressure. Furthermore, when high-NFC individuals are under low or moderate time pressure, two-sided messages are more persuasive than one-sided messages; however, message sidedness does not differentially affect the persuasion when high-NFC individuals are pressed for time. In contrast, one-sided messages are more persuasive than two-sided messages when low-NFC individuals are under low or high time pressure, and two-sided messages are more persuasive than one-sided messages when low-NFC individuals are under moderate time pressure.     

Modeling the effect of reward amount on probability discounting

The present study with college students examined the effect of amount on the discounting of probabilistic monetary rewards. A hyperboloid function accurately described the discounting of hypothetical rewards ranging in amount from $20 to $10,000,000. The degree of discounting increased continuously with amount of probabilistic reward. This effect of amount was not due to changes in the rate parameter of the discounting function, but rather was due to increases in the exponent. These results stand in contrast to those observed with the discounting of delayed monetary rewards, in which the degree of discounting decreases with reward amount due to amount-dependent decreases in the rate parameter. Taken together, this pattern of results suggests that delay and probability discounting reflect different underlying mechanisms. That is, the fact that the exponent in the delay discounting function is independent of amount is consistent with a psychophysical scaling interpretation, whereas the finding that the exponent of the probability-discounting function is amount-dependent is inconsistent with such an interpretation. Instead, the present results are consistent with the idea that the probability-discounting function is itself the product of a value function and a weighting function. This idea was first suggested by Kahneman and Tversky (1979), although their prospect theory does not predict amount effects like those observed. The effect of amount on probability discounting was parsimoniously incorporated into our hyperboloid discounting function by assuming that the exponent was proportional to the amount raised to a power. The amount-dependent exponent of the probability-discounting function may be viewed as reflecting the effect of amount on the weighting of the probability with which the reward will be received.     

Modulation of N400 in chronic non-fluent aphasia using low frequency Repetitive Transcranial Magnetic Stimulation (rTMS)

Low frequency Repetitive Transcranial Magnetic Stimulation (rTMS) has previously been applied to language homologues in non-fluent populations of persons with aphasia yielding significant improvements in behavioral language function up to 43 months post stimulation. The present study aimed to investigate the electrophysiological correlates associated with the application of rTMS through measurement of the semantic based N400 Event-related brain potentials (ERP) component. Low frequency (1 Hz) rTMS was applied to the anterior portion of the homologue to Broca’s area (pars triangularis), for 20 min per day for 10 days, using a stereotactic neuronavigational system. Twelve non-fluent persons with aphasia, 2-6 years post stroke were stimulated. Six participants were randomly assigned to receive real stimulation and six participants were randomly assigned to receive a blind sham control condition. ERP measures were recorded at baseline, 1 week and 2 months subsequent to stimulation. The findings demonstrate treatment related changes observed in the stimulation group when compared to the placebo control group at 2 months post stimulation indicating neuromodulation of N400 as a result of rTMS. No treatment related changes were identified in the stimulation group, when compared to the sham group from baseline to 1 week post stimulation. The electrophysiological results represent the capacity of rTMS to modulate neural language networks and measures of lexical-semantic function in participants with non-fluent aphasia and suggest that time may be an important factor in brain reorganization subsequent to rTMS.     

No evidence for a General Factor of Personality in the HEXACO Personality Inventory

There have been an increasing number of articles that have speculated on the existence of a General Factor of Personality (GFP) similar to ‘g’ in intelligence research. In this study, I provide evidence that this general factor may be an artifact of the personality instrument used. Specifically, in two samples I show that depending on the type of analysis used there is either no evidence for a GFP in the HEXACO Personality Inventory or the GFP is found to be uncorrelated to GFPs based on Big Five or FFM instruments.     

Do physical and relational aggression explain adolescents' friendship selection? The competing roles of network characteristics,gender, and social status

The role of physical and relational aggression in adolescents' friendship selection was examined in a longitudinal sample of 274 Chilean students from 5th and 6th grade followed over 1 year. Longitudinal social network modeling (SIENA) was used to study selection processes for aggression while influence processes were controlled for. Furthermore, the effects of network characteristics (i.e., reciprocity and transitivity), gender, and social status on friendship selection were examined. The starting assumption of this study was that selection effects based on aggression might have been overestimated in previous research as a result of failing to consider influence processes and alternative characteristics that steer friendship formation. The results show that selection effects of both physical and relational aggression disappeared when network effects, gender, and social status were taken into account. Particularly gender and perceived popularity appeared to be far more important determinants of friendship selection over time than aggression. Moreover, a peer influence effect was only found for relational aggression, and not for physical aggression. These findings suggest that similarity in aggression among befriended adolescents can be considered to be mainly a by-product rather than a leading dimension in friendship selection.     

Commonly-defined and individually-defined posttraumatic growth in the US and Japan

Posttraumatic growth (PTG) is the experience of positive change resulting from the struggle with major life crises. Research on PTG has relied on instruments such as the Posttraumatic Growth Inventory (PTGI: Tedeschi &; Calhoun, 1996), in which items that describe positive changes are assumed to represent personal growth equally for all people. However, some positive changes may indicate greater growth for some people. Individually-defined PTG may differ from commonly-defined PTG. The purpose of this study was to explore the relationships between these two definitions of PTG and how culture affects them. Participants from the US (n = 456) and Japan (n = 279) indicated the degree to which each change in the PTGI represented personal growth. Results from mixed-model analyses of variance revealed that there were main effects for defined growth as well as interaction effects for all PTGI factors. For example, US participants reported greater growth on the factors Relating to Others and New Possibilities for the commonly-defined level, but once individually-defined PTG was considered, growth scores for US participants decreased substantially, and more so than for Japanese participants. Discussion addresses cultural and individual differences in the subjective definitions of PTG and highlights several directions for future research.     

Musicians and tone-language speakers share enhanced brainstem encoding but not perceptual benefits for musical pitch

Behavioral and neurophysiological transfer effects from music experience to language processing are well-established but it is currently unclear whether or not linguistic expertise (e.g., speaking a tone language) benefits music-related processing and its perception. Here, we compare brainstem responses of English-speaking musicians/non-musicians and native speakers of Mandarin Chinese elicited by tuned and detuned musical chords, to determine if enhancements in subcortical processing translate to improvements in the perceptual discrimination of musical pitch. Relative to non-musicians, both musicians and Chinese had stronger brainstem representation of the defining pitches of musical sequences. In contrast, two behavioral pitch discrimination tasks revealed that neither Chinese nor non-musicians were able to discriminate subtle changes in musical pitch with the same accuracy as musicians. Pooled across all listeners, brainstem magnitudes predicted behavioral pitch discrimination performance but considering each group individually, only musicians showed connections between neural and behavioral measures. No brain-behavior correlations were found for tone language speakers or non-musicians. These findings point to a dissociation between subcortical neurophysiological processing and behavioral measures of pitch perception in Chinese listeners. We infer that sensory-level enhancement of musical pitch information yields cognitive-level perceptual benefits only when that information is behaviorally relevant to the listener.