A Social Problem-Solving Model of Adherence to HIV Medications.

HIV medication adherence remains a challenge and limits the degree to which treatment benefit can be maximized. This study tested an explanatory model of HIV medication adherence using a social problem-solving (SPS) framework. Associations of SPS with adherence are hypothesized to be direct and/or indirect via psychological health. HIV+ adults were interviewed using validated measures of SPS, psychological health, and antiretroviral therapy (ART) medication adherence. Structural equation modeling (SEM) techniques were used to test hypothesized relationships and to evaluate overall fit of the model to the data. SEM supported an indirect association (but not direct) of SPS on adherence via psychological health among the 545 HIV+ adults included in the analyses. Overall, the findings resulted in a model of adherence that offered very good fit to the data and correctly classified 97% of the cases as adherent versus nonadherent. Results support the use of SPS as a conceptual framework for understanding adherence to ART. Findings offer rationale and direction for SPS interventions to enhance adherence by improving psychological health. Such approaches, if effective, have the potential to positively impact psychological well being and adherence, thereby maximizing clinical benefit from treatment, which is linked to lower mortality from AIDS.     

Combining EEG,MIDI, and motion capture techniques for investigating musical performance

This article describes a setup for the simultaneous recording of electrophysiological data (EEG), musical data (MIDI), and three-dimensional movement data. Previously, each of these three different kinds of measurements, conducted sequentially, has been proven to provide important information about different aspects of music performance as an example of a demanding multisensory motor skill. With the method described here, it is possible to record brain-related activity and movement data simultaneously, with accurate timing resolution and at relatively low costs. EEG and MIDI data were synchronized with a modified version of the FTAP software, sending synchronization signals to the EEG recording device simultaneously with keypress events. Similarly, a motion capture system sent synchronization signals simultaneously with each recorded frame. The setup can be used for studies investigating cognitive and motor processes during music performance and music-like tasks—for example, in the domains of motor control, learning, music therapy, or musical emotions. Thus, this setup offers a promising possibility of a more behaviorally driven analysis of brain activity.     

Facial electromyography reveals dissociable affective responses in social and non-social cooperation

While economic standard theory explains cooperation in terms of rational decision-making, empirical studies suggest that humans have social preferences for cooperating with others. We investigated the specificity of these social preferences for interactions with human, relative to non-human, agents in a prisoner’s dilemma game. To obtain insights into emotional processes during cooperation, we measured activity of the corrugator supercilii muscle as indicator of spontaneous emotional responding during cooperation. After unreciprocated defection (free-riding), participants switched more often to a cooperative strategy and showed increased corrugator activity (suggesting more negative emotional responses) when playing with a human relative to a computer. This suggests that humans have a specific preference for cooperating with other humans and that cooperation may be promoted by unpleasant affect in response to the outcome of one’s own “free-riding”.     

Reminders of an agentic ingroup buffer disease uncontrollability

Chronic illness has negative impacts beyond those on physical health. In particular, because it is often experienced as uncontrollable, chronic illness might reduce people's general sense of personal control and, subsequently, personal well-being. Drawing on recent theory and research, we proposed and tested in four experiments (N_total = 1323) a potential buffer to these negative effects: thinking about an agentic social ingroup in one's life. In Study 1, patients suffering from a chronic illness that was either high or low in medical disease controllability were asked either to think about an agentic ingroup or a personal issue. Low perceived disease-related control was associated with low perceived personal control only when participants' personal self, but not when their ingroup, was salient. In three follow-up vignette studies, we asked participants to take the perspective of a person who suffered from a health problem of low medical disease controllability and attended a self-help group that was described as either high or low in agency. The findings supported the predicted buffering effect: participants who reflected on a target suffering from a low control disease thought that the target would experience more personal control when the agentic (vs. the nonagentic) self-help group was salient. These findings suggest ingroups can serve as a source of personal control in the context of health-related threats to the extent that they are perceived as agentic. Thus, focusing on agentic properties of (health-related) ingroups might be a promising novel strategy when designing effective group-based interventions to cope with chronic illness.     

Task switching: effects of practice on switch and mixing costs

In the task-switching paradigm, mixing costs indicate the performance costs to mix two different tasks, while switch costs indicate the performance costs to switch between two sequentially presented tasks. Applying tasks with bivalent stimuli and responses, many studies demonstrated substantial mixing and switch costs and a reduction of these costs as a result of practice. The present study investigates whether extensive practice of a task-switching situation including tasks with univalent stimuli eliminates these costs. Participants practiced switching between a visual and an auditory task. These tasks were chosen because they had shown eliminated performance costs in a comparable dual-task practice study (Schumacher et al. Psychol Sci 12:101–108, 2001). Participants either performed the tasks with univalent responses (i.e., visual-manual and auditory-verbal stimulus–response mappings) or bivalent responses (i.e., visual-manual and auditory-manual stimulus–response mappings). Both valence conditions revealed substantial mixing and switch costs at the beginning of practice, yet, mixing costs were largely eliminated after eight practice sessions while switch costs were still existent.     

Setting things straight: A comparison of measures of saccade trajectory deviation

In eye movements, saccade trajectory deviation has often been used as a physiological operationalization of visual attention, distraction, or the visual system’s prioritization of different sources of information. However, there are many ways to measure saccade trajectories and to quantify their deviation. This may lead to noncomparable results and poses the problem of choosing a method that will maximize statistical power. Using data from existing studies and from our own experiments, we used principal components analysis to carry out a systematic quantification of the relationships among eight different measures of saccade trajectory deviation and their power to detect the effects of experimental manipulations, as measured by standardized effect size. We concluded that (1) the saccade deviation measure is a good default measure of saccade trajectory deviation, because it is somewhat correlated with all other measures and shows relatively high effect sizes for two well-known experimental effects; (2) more generally, measures made relative to the position of the saccade target are more powerful; and (3) measures of deviation based on the early part of the saccade are made more stable when they are based on data from an eyetracker with a high sampling rate. Our recommendations may be of use to future eye movement researchers seeking to optimize the designs of their studies.     

Concurrent deployment of visual attention and response selection bottleneck in a dual-task: Electrophysiological and behavioural evidence

Visual attention and response selection are limited in capacity. Here, we investigated whether visual attention requires the same bottleneck mechanism as response selection in a dual-task of the psychological refractory period (PRP) paradigm. The dual-task consisted of an auditory two-choice discrimination Task 1 and a conjunction search Task 2, which were presented at variable temporal intervals (stimulus onset asynchrony, SOA). In conjunction search, visual attention is required to select items and to bind their features resulting in a serial search process around the items in the search display (i.e., set size). We measured the reaction time of the visual search task (RT2) and the N2pc, an event-related potential (ERP), which reflects lateralized visual attention processes. If the response selection processes in Task 1 influence the visual attention processes in Task 2, N2pc latency and amplitude would be delayed and attenuated at short SOA compared to long SOA. The results, however, showed that latency and amplitude were independent of SOA, indicating that visual attention was concurrently deployed to response selection. Moreover, the RT2 analysis revealed an underadditive interaction of SOA and set size. We concluded that visual attention does not require the same bottleneck mechanism as response selection in dual-tasks.     

Fluency heuristic: a model of how the mind exploits a by-product of information retrieval

Boundedly rational heuristics for inference can be surprisingly accurate and frugal for several reasons. They can exploit environmental structures, co-opt complex capacities, and elude effortful search by exploiting information that automatically arrives on the mental stage. The fluency heuristic is a prime example of a heuristic that makes the most of an automatic by-product of retrieval from memory, namely, retrieval fluency. In 4 experiments, the authors show that retrieval fluency can be a proxy for real-world quantities, that people can discriminate between two objects' retrieval fluencies, and that people's inferences are in line with the fluency heuristic (in particular fast inferences) and with experimentally manipulated fluency. The authors conclude that the fluency heuristic may be one tool in the mind's repertoire of strategies that artfully probes memory for encapsulated frequency information that can veridically reflect statistical regularities in the world.     

The use of recognition in group decision-making

Goldstein and Gigerenzer (2002) [Models of ecological rationality: The recognition heuristic. Psychological Review, 109 (1), 75-90] found evidence for the use of the recognition heuristic. For example, if an individual recognizes only one of two cities, they tend to infer that the recognized city has a larger population. A prediction that follows is that of the less-is-more effect: Recognizing fewer cities leads, under certain conditions, to more accurate inferences than recognizing more cities. We extend the recognition heuristic to group decision-making by developing majority and lexicographic models of how recognition information is used by groups. We formally show when the less-is-more effect is predicted in groups and we present a study where three-member groups performed the population comparison task. Several aspects of our data indicate that members who can use the recognition heuristic are, not in all but in most cases, more influential in the group decision process than members who cannot use the heuristic. We also observed the less-is-more effect and found that models assuming that members who can use the recognition heuristic are more influential better predict when the effect occurs.     

VOLITIONAL ASPECTS OF VOICE PERFORMANCE: AN EXPERIMENTAL APPROACH

The subjects (all females) were instructed to hold a certain note. In some of the trials an alien (female) voice with a continuously falling or rising frequency unexpectedly replaced the subject's own voice as the auditory stimulus in her headphone. Most of the subjects took the alien voice as their own and experienced a complete lack of volitional control over their own voice. A compensatory behaviour was found; when the subjects tried to hold the note the frequency of their voices went in the opposite direction to the frequency of the alien voice.