Inattentional blindness for negative relationships in human causal learning

The present study focuses on the effect of selective attention on causal learning. Three effects of the level of attention to predictive symptoms in positive and negative contingency learning tasks are reported. First, participants accurately detected a positive relationship between an incidental cue and a contingent outcome, although judgements were slightly lower than those for the attended cue. Second, participants were unable to detect negative relationships between incidental cues and outcomes, which suggests a major role of selective attention in this type of learning. Third, participants retrieved the frequency of each trial type more accurately in the attended conditions than in the incidental conditions. These findings show how attention guides and constrains human causal learning and reveal an inattentional blindness effect for negative contingency learning.     

Mood reactivity to daily negative events in early adolescence: relationship to risk for psychopathology

Emotional responses to negative daily experiences in young adolescents may provide important clues to the development of psychopathology, but research is lacking. This study assessed momentary mood reactivity to daily events as a function of risk profile in a school sample, ages 11-14. High-risk (HR, n=25) and low-risk (LR, n=106) subgroups completed frequent self-reports of mood and events for 5 days. HR adolescents reported more negative events involving family and peers. Multilevel modeling results showed that negative events, especially if stressful, were associated with increased negative and decreased positive affects, with heightened responses in HR adolescents. HR adolescents with greater stress over the last 3 months showed additional increases in depressed mood following negative events. Altered reactivity to and dysfunctional appraisals of daily events may link adolescent risk profiles to later mental health problems.     

Consistent contrast and correlation in free sorting

Two experiments investigated free sorting, a type of unsupervised learning, with multiattribute drawings of alien animals. In previous research on concept formation, with simpler stimulus structure than ours, participants were insensitive to correlational structure in the stimuli, producing primarily "ID sorts," based on the values ofjust 1 dimension or attribute. Our experiments showed that participants used many strategies in categorizing but preferred to generate groupings that reflected the correlations in input when this did not violate consistent contrast. The second experiment used hierarchically structured stimuli to show that participants' sort strategies favor consistency within a set of contrasting categories, distinct from any preference for 1D sorting. Finally, both experiments show that correlational sorts are much more likely when the correlation-based sort contrasts consistently. Our data show complexity at work in free sort tasks: People are sensitive to multiple and sometimes conflicting biases for consistency and correlational structure in the category systems they create.     

Sequence learning under dual-task conditions: alternatives to a resource-based account

In two experiments with the serial reaction-time task, participants were presented with deterministic or probabilistic sequences under single- or dual-task conditions. Experiment 1 showed that learning of a probabilistic structure was not impaired over a first session by performing a counting task, but that such an interference arose over a second session, when the knowledge was tested under single-task conditions. In contrast, the effects of the secondary task arose earlier for participants exposed to deterministic sequences. This difference between deterministic and probabilistic sequences disappeared in Experiment 2, where the counting task was performed on tones associated to the locations. Comparisons between sessions indicated that the secondary task affected not only the expression but also the acquisition of sequence learning, and that greater interference was observed in those conditions that yielded more explicit knowledge. These results suggest that the effects of a dual task on the measures of implicit sequence learning may be partly due to the intrusion of explicit knowledge and partly due to the disruption of the sequence produced by the inclusion of random events.     

The role of temporal and spatial factors in the covert orienting of visual attention tasks

There is a biphasic pattern in response times to peripheral uninformative cues, with faster responses to targets in cued locations when the stimulus onset asynchrony (SOA) is under 300 ms and slower responses when it is over 300 ms. The effect has typically been attributed entirely to the SOA while ignoring other aspects of the cues (duration, spatial configuration). To examine these other factors, along with SOA, the present experiments included manipulations of SOA (50, 100, 200, 400, 800 ms), inter-stimulus interval (ISI; 0, 50, 100, 150, 200, 300, 350, 400, 500, 600, 700, and 750 ms), and whether or not the cue and target overlap in the same space. The results indicate that cueing effects depend on the combination of cue duration, ISI, SOA, and the spatial configuration of the cues and targets. Three factors are used to explain these time course results.     

Positive emotions in volunteerism

Volunteerism is a well consolidated social phenomenon in our society. However, its rapid growth in the last few years has complicated the integration of theoretical knowledge and its application in organizational settings. Taking into account that nowadays, one of the chief problems of volunteer organizations is sustained volunteer service, the object of this work is to verify, within the context of the psychosocial model of sustained volunteerism (Vecina, 2001), the type of relation between the experience of positive emotions in volunteers and their intention of remaining in the organization. This work was carried out on a sample of volunteers who had been in service for less than one year prior to this study.     

Directed attention in Gilles de la Tourette syndrome

Gilles de la Tourette syndrome (TS) is a basal ganglia (BG) disorder, associated not only with hyperkinetic movements but also with attentional impairments. This experiment sought to ascertain whether overt direct visual attention would influence tactile attentional performance in TS, via the use of a vibrotactile choice reaction time procedure involving biased probabilities of event occurrence. Participants were required to look (i.e., direct gaze) either at the hand receiving the most (expected) vibrations, or the hand less often stimulated (the unexpected), for both crossed and uncrossed arm postures. Contrary to our predictions, gaze did not influence attentional performance in TS patients. Furthermore, patients were found not to be sensitive to distributions of event probability; that is, they did not demonstrate normal expectancy effects like controls. Attentional deficits in TS (as in Parkinson's disease, another BG disorder) may pertain more to difficulties in holding rather than in shifting the focus of attention. Moreover, directing attention towards the unexpected locus in the crossed arm posture improved overall performance in both patients and controls, suggesting that increased task demands (e.g., crossed arm posture), and/or unexpected stimulus location, may be alleviated by directed attention. These impairments may stem from dysfunction in the circuits linking the frontal lobes with the BG.     

Anti-realist truth and concepts of superassertibility

Crispin Wright offers superassertibility as an anti-realist explication of truth. A statement is superassertible, roughly, if there is a state of information available which warrants it and it is warranted by all achievable enlargements of that state of information. However, it is argued, Wright fails to take account of the fact that many of our test procedures are not sure fire, even when applied under ideal conditions. An alternative conception of superassertibility is constructed to take this feature into account. However, it is then argued that when this revised concept of superassertibility is taken as the truth predicate of probability statements, statements whose test procedures are paradigmatically not sure fire, then any anti-realist theory of the sense of such probability statements cannot be compositional, in Dummett's sense of compositional.     

Dewey's philosophy and the experience of working: Labor,tools and language

Although Richard Rorty has done much to renew interest in the philosophy of John Dewey, he nonetheless rejects two of the most important components of Dewey's philosophy, that is, his metaphysics and epistemology. Following George Santayana, Rorty accuses Dewey of trying to serve Locke and Hegel, an impossibility as Rorty rightly sees it. Rorty (1982) says that Dewey should have been “Hegelian all the way” (p. 85). By reconstructing a bit of Hegel's early philosophy of work, and comparing it to Dewey's metaphysics and epistemology we can see that Dewey was indeed “Hegelian all the way” and that Rorty has constructed a false dilemma. We also gain some interesting insight into Dewey's philosophy by viewing it in terms of labor, tools and language.