Psychological variables in the control of brain-computer interfaces

BCI (Brain-Computer Interface) is a system that allows interaction between the human brain and a computer. It is based on analyzing electroencephalographic signals (EEG) and processing them to generate control commands. The study analyzed the possible influence of psychological variables, such as the imaginative kinesthetic capacity and anxiety, in relation to performance in a BCI. All participants (4 male and 19 female students) completed the questionnaires and carried out a session of BCI to control their EEG signals in a virtual setting of a car along a straight road. The group was divided into two subgroups according to their EEG signals or differential responses obtained in the left-right discrimination. Study results showed no significant differences in cognitive variables of imagination or in anxiety. By comparing the degree of participants' BCI control, a new quantitative parameter for comparing performances and making decisions in signal processing was found. The findings, the ongoing research process to refine the control of a BCI, and the interaction of psychological and computer procedures are discussed.     

Age-related differences in working memory: ERPs reveal age-related delays in selection- and inhibition-related processes

Faulty inhibition is implicated in age-related working memory decline. ERP signs of selection and inhibition of items in working memory (WM) are, respectively, a cue-locked parietal positivity (～350 ms) and a probe-locked frontal negativity (～520 ms). To determine when in the older age range differences in selective and inhibitory processes might occur, ERPs were recorded in a WM task from 20 young (20–28), 20 young–old (60–70), and 20 old–old (71–82) adults. A 4-digit display was followed by a cue indicating which 2 of 4 digits were relevant. Proactive interference (PI), the reaction time difference between a matching and non-matching to-be-ignored digit was larger, relative to the young, in both older groups. Compared to the young, both the cue- and probe-locked activities were prolonged in the older groups. Although there were no topographic differences among the age groups, the prolonged PI and associated ERPs suggest a relative age-related deficit in inhibition.     

For the greater goods? Ownership rights and utilitarian moral judgment

People often judge it unacceptable to directly harm a person, even when this is necessary to produce an overall positive outcome, such as saving five other lives. We demonstrate that similar judgments arise when people consider damage to owned objects. In two experiments, participants considered dilemmas where saving five inanimate objects required destroying one. Participants judged this unacceptable when it required violating another’s ownership rights, but not otherwise. They also judged that sacrificing another’s object was less acceptable as a means than as a side-effect; judgments did not depend on whether property damage involved personal force. These findings inform theories of moral decision-making. They show that utilitarian judgment can be decreased without physical harm to persons, and without personal force. The findings also show that the distinction between means and side-effects influences the acceptability of damaging objects, and that ownership impacts utilitarian moral judgment.     

Augmenting treatment efficiency in exposure therapy for PTSD: a randomized double-blind placebo-controlled trial of yohimbine HCl

The alpha-2 adrenergic receptor antagonist, yohimbine, can facilitate fear extinction in animals and humans. One potential mechanism is increased noradrenergic activity and associated arousal in the presence of conditioned stimuli. Accordingly, yohimbine might augment prolonged exposure (PE) therapy for posttraumatic stress disorder (PTSD), where heightened exposure-oriented arousal is a theorized driver and empirical predictor of treatment success. A double-blind placebo-controlled randomized trial (NCT 01031979) piloted yohimbine augmentation in 26 males with combat-related PTSD. Participants were given one-time dose of yohimbine or placebo prior to the first imaginal exposure. Subsequently, both arms completed standard PE. The primary outcome was trauma-cued heart-rate reactivity a week after the drug/exposure visit, a highly specified, objective measure sensitive to incremental change. Secondary outcomes included arousal during the drug/exposure visit and slope of distress, PTSD, and depression over the course of PE. Consistent with hypothesis, yohimbine led to higher objective and subjective arousal during the drug/exposure visit and to lower trauma-cued heart-rate reactivity one-week later. One dose of yohimbine also led to greater between-session habituation and more rapid improvement on depression, but not PTSD, over the course of care. Results of this controlled pilot indicate support for continued investigation of yohimbine-augmented exposure therapy for PTSD.     

Effects of exposure to alcohol‐related cues on racial discrimination

Prior research has shown that exposure to alcohol‐related images exacerbates expression of implicit racial biases, and that brief exposure to alcohol‐related words increases aggressive responses. However, the potential for alcohol cue exposure to elicit differential aggression against a Black (outgroup) relative to a White (ingroup) target—that is, racial discrimination—has never been investigated. Here, we found that White participants (N = 92) exposed to alcohol‐related words made harsher judgments of a Black experimenter who had frustrated them than participants who were exposed to nonalcohol words. These findings suggest that exposure to alcohol cues increases discriminatory behaviors toward Blacks.     

Proverb preferences across cultures: Dialecticality or poeticality?

Peng and Nisbett (1999) claimed that members of Asian cultures show a greater preference than Euro-Americans for proverbs expressing paradox (so-called dialectical proverbs; e.g.,Too humble is half proud). The present research sought to replicate this claim with the same set of stimuli used in Peng and Nisbett’s Experiment 2 and a new set of dialectical and nondialectical proverbs that were screened to be comparably pleasing in phrasing. Whereas the proverbs were rated as more familiar and (in Set 1) more poetic by Chinese than by American participants, no group differences were found in relation to proverb dialecticality. Both the Chinese and Americans in our study rated the dialectical proverbs from Peng and Nisbett’s study as more likable, higher in wisdom, and higher in poeticality than the nondialectical proverbs. For Set 2, both groups found the dialectical proverbs to be as likable, wise, and poetic as the nondialectical proverbs. When poeticality was covaried out, dialectical proverbs were liked better than nondialectical proverbs across both stimulus sets by the Chinese and the Americans alike, and when wisdom was covaried out, the effect of dialecticality was reduced in both sets and groups. Our findings indicate that caution should be taken in ascribing differences in proverb preferences solely to cultural differences in reasoning.     

Similes on the Internet have explanations

We searched the Internet for expressions linking topics, such as crime, and vehicles, such as disease, as similes (crime is like a disease) and as metaphors (crime is a disease). We counted the number of times the expressions were accompanied by explanations (crime is like a disease because it spreads by direct personal influence). Similes were more likely than metaphors to be accompanied by explanations. Similes may be preferred if a writer wants to express an out-of-the-ordinary relation between the topic and the vehicle.