Dividing Attention Between Tasks: Testing Whether Explicit Payoff Functions Elicit Optimal Dual‐Task Performance

We test people's ability to optimize performance across two concurrent tasks. Participants performed a number entry task while controlling a randomly moving cursor with a joystick. Participants received explicit feedback on their performance on these tasks in the form of a single combined score. This payoff function was varied between conditions to change the value of one task relative to the other. We found that participants adapted their strategy for interleaving the two tasks, by varying how long they spent on one task before switching to the other, in order to achieve the near maximum payoff available in each condition. In a second experiment, we show that this behavior is learned quickly (within 2–3 min over several discrete trials) and remained stable for as long as the payoff function did not change. The results of this work show that people are adaptive and flexible in how they prioritize and allocate attention in a dual‐task setting. However, it also demonstrates some of the limits regarding people's ability to optimize payoff functions.     

Normative and Maladaptive Personality Trait Models of Mood,Psychotic, and Substance Use Disorders

The Personality Inventory for DSM-5 (PID-5) is a questionnaire developed to assess the five domains represented in the alternative model for personality disorders proposed in Section III of the DSM-5. This study examined the ability of the PID-5 to distinguish between different mental disorders compared to a questionnaire measure of the five-factor model (FFM) of normative personality. The study included the administration of the PID-5 and Revised NEO Personality Inventory (NEO PI-R), a measure of the FFM, to treatment-seeking individuals with Depressive, Bipolar, Psychotic, and Alcohol Use Disorders (AUD). Diagnostic groups were compared at the domain level of PID-5 and NEO PI-R, with sex and age as covariates. The main findings on the PID-5 included higher Detachment scores for Bipolar and Depressive Disorders than Psychotic and AUDs, lower Psychoticism/higher Disinhibition scores for the AUD group compared to all other groups, and lower Negative Affect for the Psychotic Disorders versus AUD group. On the NEO PI-R, the AUD diagnostic group was associated with lower Conscientiousness and Agreeableness scores compared to all other groups, and lower Neuroticism scores than the Bipolar and Depressive groups. Group pairwise comparisons did not appear to show many differences between the PID-5 and NEO PI-R. The results suggest that the alternative DSM-5 model for personality disorders may have clinical utility in distinguishing personality profiles between diagnostic groups. These findings emphasize the importance of additional research on the capacity of maladaptive personality to contribute to the assessment of differential diagnoses.     

Simple games as dynamic, coupled systems: randomness and other emergent properties

From a game theory perspective the ability to generate random behaviors is critical. However, psychological studies have consistently found that individuals are poor at behaving randomly. In this paper we investigated the possibility that the randomness mechanism lies not within the individual players but in the interaction between the players. Provided that players are influenced by their opponent’s past behavior, their relationship may constitute a state of reciprocal causation [Cognitive Science 21 (1998) 461], in which each player simultaneously affects and is affected by the other player. The result of this would be a dynamic, coupled system. Using neural networks to represent the individual players in a game of paper, rock, and scissors, a model of this process was developed and shown to be capable of generating chaos-like behaviors as an emergent property. In addition, it was found that by manipulating the control parameters of the model, corresponding to the amount of working memory and the perceived values of different outcomes, that the game could be biased in favor of one player over the other, an outcome not predicted by game theory. Human data was collected and the results show that the model accurately describes human behavior. The results and the model are discussed in light of recent theoretical advances in dynamic systems theory and cognition.     

Assessing group-level participation in fluid teams: testing a new metric

Participation is an important factor in team success. We propose a new metric of participation equality that provides an unbiased estimate across groups of different sizes and across those that change size over time. Using 11 h of transcribed utterances from informal, fluid, colocated workgroup meetings, we compared the associations of this metric with coded equality of participation and standard deviation. While coded participation and our metric had similar patterns of findings, standard deviation had a somewhat different pattern, suggesting that it might lead to incorrect assessments with fluid teams. Exploratory analyses suggest that, as compared with mixed-age/status groups, groups of younger faculty had more equal participation and that the presence of negative affect words was associated with more dominated participation. Future research can take advantage of this new metric to further theory on team processes in both face-to-face and distributed settings.     

Can computer mice be used as low-cost devices for the acquisition of planar human movement velocity signals?

The main goal of this work is to determine whether a computer mouse can be used as a low-cost device for the acquisition of two-dimensional human movement velocity signals in the context of psychophysical studies and biomedical applications. A comprehensive overview of the related literature is presented, and the problem of characterizing mouse movement acquisition is analyzed and discussed. Then, the quality of velocity signals acquired with this kind of device is measured on horizontal oscillatory movements by comparing the mouse data to the signals acquired simultaneously by a video motion tracking system and a digitizing tablet. A synthesis of the information gathered in this work indicates that the computer mouse can be used for the reliable acquisition of biosignals in the context of human movement studies, particularly for many applications dealing with the velocity of the end effector of the upper limb. This paper concludes by discussing the possibilities and limitations of such use.     

酒精对视觉加工和眼动行为控制的影响(中文)

Although moderate alcohol consumption is known to degrade performance in a variety of tasks, the exact nature and extent of such impairments is not well understood. We examined alcohol effects on different levels of visual processing and oculomotor control. On the lowest level(automatic), reflexive responses were tested using the prosaccade task. The‘automated’level, incorporating routine behavior based on implicit learning, was studied using the double step paradigm, while the highest level, representing voluntary control, was examined with antisaccade and memory guided tasks. In addition, sentence reading was included as a prototypical complex task with high ecological validity. Participant′s baseline performance was compared to alcohol conditions with intoxication levels around 70mg% of breath alcohol concentration. Functioning on the automatic level was intact, except for a substantial slowing in saccade latencies. On the automated level, deficits in the ability to adaptively reprogram saccades on the basis of new information were found. Impairments in voluntary control were apparent in hypermetric saccade amplitudes whenever a reprogramming of the initial saccade target was necessary. There was also a small but significant detrimental effect on visuospatial short term memory. Somewhat surprisingly, no alcohol related deficits emerged with regard to inhibitory functions. ‘Reading under the influence’resulted in substantially prolonged fixation durations with only a modest increase in total viewing time per word. A trade-off between increased duration and decreased number of fixations pointed to the possibility that the extra time available under alcohol can be used for linguistic processing, which in itself did not appear to be impaired. This idea is supported by the fact that there was no interaction between alcohol and word frequency. Contrary to expectation, the processing of parafoveal information during reading was not impeded. Overall, results provide a largely coherent pattern of selective effects that begin to form a comprehensive picture of alcohol related deficits.     

Watching pornographic pictures on the Internet: role of sexual arousal ratings and psychological-psychiatric symptoms for using Internet sex sites excessively

Excessive or addictive Internet use can be linked to different online activities, such as Internet gaming or cybersex. The usage of Internet pornography sites is one important facet of online sexual activity. The aim of the present work was to examine potential predictors of a tendency toward cybersex addiction in terms of subjective complaints in everyday life due to online sexual activities. We focused on the subjective evaluation of Internet pornographic material with respect to sexual arousal and emotional valence, as well as on psychological symptoms as potential predictors. We examined 89 heterosexual, male participants with an experimental task assessing subjective sexual arousal and emotional valence of Internet pornographic pictures. The Internet Addiction Test (IAT) and a modified version of the IAT for online sexual activities (IATsex), as well as several further questionnaires measuring psychological symptoms and facets of personality were also administered to the participants. Results indicate that self-reported problems in daily life linked to online sexual activities were predicted by subjective sexual arousal ratings of the pornographic material, global severity of psychological symptoms, and the number of sex applications used when being on Internet sex sites in daily life, while the time spent on Internet sex sites (minutes per day) did not significantly contribute to explanation of variance in IATsex score. Personality facets were not significantly correlated with the IATsex score. The study demonstrates the important role of subjective arousal and psychological symptoms as potential correlates of development or maintenance of excessive online sexual activity.     

Great oaks from giant acorns grow: How causal‐impact judgments depend on the strength of a cause

Causal impact is maximal when weak causes have strong effects. Do people understand this logic when they assess causal impact? In four experiments, participants judged the causal impact of strong or weak dietary treatments leading to strong or weak health effects in fictitious health studies. Rather than following the ratio of effect strength to treatment strength, judgments were influenced by three aspects of the detectability of a cause–effect relation. First, because detectability depends on the effect being strong more than on the cause being subtle, causal judgments were mainly determined by effect strength, whereas the strength of the causal treatment necessary to induce an effect was often neglected. Second, if causal input was not ignored, judgments increased when the maximal covariation between a strong causal treatment and a strong effect rendered the causal link most detectable. Or, third, causal judgments increased when a plausible causal schema facilitated detection. Consistent with sampling models of judgment and decision making, causal‐impact ratings were driven by an uncritical assessment of a detectable difference in a study sample. However, ratings were insensitive to the logical implications of the underlying causal treatment that was necessary to induce a detectable effect. Copyright © 2010 John Wiley & Sons, Ltd.