The Timing of Conscious Experience: A Critical Review and Reinterpretation of Libet''s Research

An extended examination of Libet's works led to a comprehensive reinterpretation of his results. According to this reinterpretation, the Minimum Train Duration of electrical brain stimulation should be considered as the time needed to create a brain stimulus efficient for producing conscious sensation and not as a basis for inferring the latency for conscious sensation of peripheral origin. Latency for conscious sensation with brain stimulation may occurafterthe Minimum Train Duration. Backward masking with cortical stimuli suggests a 125–300 ms minimum value for the latency for conscious sensation of threshold skin stimuli. Backward enhancement is not suitable for inferring this latency. For determining temporal relations between stimuli that correspond to subjects' reports, theendof cerebral Minimum Train Duration should be used as reference, rather than its onset. Results of coupling peripheral and cortical stimuli are explained by a latency after the cortical Minimum Train Duration, having roughly the same duration as the latency for supraliminal skin stimuli. Results of coupling peripheral stimuli and stimuli to medial lemniscus (LM) are explained by a shorter LM latency and/or a longer peripheral latency. This interpretation suggests a 230 ms minimum value for the latency for conscious sensation of somatosensory near-threshold stimuli. The backward referral hypothesis, as formulated by Libet, should not be retained. Long readiness potentials preceding spontaneous conscious or nonconscious movements suggest that both kinds of movement are nonconsciously initiated. The validity of Libet's measures of W and M moments (Libet et al., 1983a) is questionable due to problems involving latencies, training, and introspective distinction of W and M. Veto of intended actions may be initially nonconscious but dependent on conscious awareness.     

Session duration and the VI response function: Within-session prospective and retrospective effects

Two experiments examined the effects of session duration on responding during simple variable-interval schedules. In Experiment 1, rats were exposed to a series of simple variable-interval schedules differing in both session duration (10 min or 30 min) and scheduled reinforcement rate (7.5 s, 15 s, 30 s, and 480 s). The functions relating response rate to reinforcement rate were predominantly monotonic for the short (10-min) sessions but were predominantly bitonic for the long (30-min) sessions, when data from the entire session were considered. Examination of responding within sessions suggested that differences in the whole-session data were produced by a combination of prospective processes (i.e., processes based on events scheduled to occur later in the session) and retrospective processes (i.e., processes based on events that had already occurred in the session). In Experiment 2, rats were exposed to a modified discrimination procedure in which pellet flavor (standard or banana) predicted session duration (10 min or 30 min). All rats came to respond faster during the short (10-min) sessions than during the first 10 min of the long sessions. As in Experiment 1, the results seemed to reflect the simultaneous operation of both prospective and retrospective processes. The results shed light on the recent controversy over the form of the variable-interval response function by identifying one variable (session duration) and two types of processes (prospective and retrospective) that influence responding on these schedules.     

Theoretical and methodological directions in mindset intervention research

Growth mindset interventions directed at students aim to change students' beliefs about the malleability of ability. These interventions have had mixed results, with some showing impressive findings (e.g., improving grades and persistence in science and closing performance gaps), while other implementations have shown null findings. This heterogeneity suggests that growth mindset interventions should not be viewed as a sole solution for improving educational outcomes for students and that further research is needed to identify the contextual factors that influence their effectiveness. We propose new theoretical directions in mindset research that adopts an anti-deficit model and moves away from focusing exclusively on students and their belief systems. Instead, we encourage a new wave of mindset research that considers the institutional, cultural, and contextual environment that either corroborates or negates students' mindset beliefs. We propose a new approach to mindset research that emphasizes innovative approaches to better understand the conditions under which mindset interventions are effective.     

Effects of quantity and quality of home proximal processes on Dutch,Surinamese–Dutch and Turkish–Dutch pre‐schoolers’ cognitive development

This study examines the effects of mother–child literacy and problem solving interactions on 3–4‐year‐old children's cognitive development in a sample of Dutch middle‐class, Dutch lower‐class, Surinamese and Turkish immigrant families (n=130). Following the bioecological model of Bronfenbrenner and Ceci, mother–child book reading and problem solving interactions are viewed as proximal processes actualizing genetic cognitive potential. Interactions are studied from a quantitative perspective, based on questionnaire data, concerning frequency of exposure to these interactions, and a qualitative perspective, based on observational data, concerning affective quality and cognitive content. The study was designed as a 1 year longitudinal study. It was found that effects of mother–child interactions on cognitive development differed across the groups, controlling for earlier cognitive competence and family's SES. The findings are interpreted within the frame of the bioecological model and the behavioral genetic research paradigm. Copyright © 1999 John Wiley & Sons, Ltd.     

Rank disagreement: A comparison of multi-criteria methodologies

A number of multi-criteria decision support techniques have emerged in recent years that use varying computational approaches to arrive at the most desirable solution and thereby ‘recommend’ a course of action. Decision makers who use the results of this analytic work should be assured that the computational schemes used by their supporting analysts or decision support software produce the appropriate solutions. We conducted a series of simulation experiments that compared the top-ranked options resulting from the computational algorithms that support Multi-Attribute Value Theory (MAVT) and three methods that are reported in the literature that allow rank reversals, the change in rank order of two options when an unrelated option is added or deleted from the analysis: the Analytical Hierarchy Process (AHP), Percentaging and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). We also included a Fuzzy algorithm proposed by Yager to gauge its consistency with the other algorithms, even though it is not subject to rank reversals. These experiments demonstrated that the MAVT and AHP techniques, when provided with the same decision outcome data, very often identify the same alternative as ‘best’. The other techniques are noticeably less consistent with MAVT, the Fuzzy algorithm being the least consistent. The situations under which the most frequent and significant differences occurred were dependent upon the method. The results of our experiments indicate that other issues (e.g. the processes used for problem structuring and the elicitation of value weights) are likely to be of greater significance to problem outcome (based on our experience) than the choice between the computational algorithms of MAVT and AHP. The results cause us to be concerned about the use of the other methods.     

A Social Network Analysis of Friendship and Spiritual Support in a Religious Congregation

Religious congregations are social settings where people gather together in community to pursue the sacred (Pargament, 2008). Such settings are important to understand as they provide a context for individuals to develop relationships, share ideas and resources, and connect individuals to larger society (Todd, 2017a). Yet, research to date has not deeply examined the inherently relational nature of religious congregations. Thus, in this study, we used social settings theory (Seidman, 2012; Tseng & Seidman, 2007) to develop and test hypotheses about relationships within one Christian religious congregation. In particular, we used social network analysis to test hypotheses about relational activity, popularity, and homophily for friendship and spiritual support types of relational links. Our findings demonstrate how relational patterns may be linked to participation in congregational activities, occupying a leadership role, a sense of community and spiritual satisfaction, stratification, socialization, and spiritual support. Overall, this advances theory and research on the relational aspects of religious congregations, and more broadly to the literature on social settings. Limitations, directions for future research, and implications for theory and religious congregations also are discussed.     

The role of attentional slippage in Stroop dilution

The present study examined the cognitive locus of Stroop dilution using a psychological refractory period (PRP) paradigm. Participants were asked to perform a tone discrimination task via a bimanual keypress response and a modified Stroop task via a vocal response serially as Task 1 and Task 2, respectively. In Task 2, a neutral word was added on half of the trials and no neutral word on the other half of the trials to observe the Stroop dilution effect. The amount of Stroop dilution, as well as the Stroop effect, was relatively constant across different stimulus-onset asynchronies (SOAs), which implies that Stroop dilution occurs due to the competition between a neutral word and a color word after a target color bar is selected to be processed further. These results indicate that focused attention plays an important role in the modulation of Stroop interference by the presence of a neutral word.     

Identity Processes and Environmental Threat: the Effects of Nationalism and Local Identity upon Perception of Beach Pollution

This study examines the importance of local and national identity processes in predicting the perception of a threat to the local environment: pollution of British beaches defined in terms of European Union (EU) regulations concerning cleanliness. Place identity and social identity theories would predict that English people would exhibit positive discrimination when evaluating both their local and national beaches and would allow ingroup preferences to influence their estimates of beach pollution. The study involved administering questionnaires to 347 English students drawn from secondary schools in six seaside resorts (three with ‘polluted’ beaches, and three with ‘unpolluted’ beaches according to the EU criteria). It was hypothesized that degree of both local and national identification would predict variance in perceived levels of pollution independently of either the EU categorization or the physical evidence of pollution available. On the whole, results confirmed this main hypothesis: subjects who were more attached to their town or their nation tended to perceive their local and national beaches as less polluted. Traditional predictors of environmental evaluation (such as socio-demographic variables, environmental concern, use of the environment) did not play an important role in predicting beach pollution perception. Denial of physical assessments of pollution was interpreted as a strategy used to cope with the threat to place identity posed by the labelling of local beaches by a powerful outgroup (the EU).