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The nature of good information processing is outlined as determined by intact neurology, information stored in long-term memory, and general cognitive tendencies, attitudes, and styles. Educators can promote the development of good information processing by promoting what is in long-term memory. This can be accomplished by teaching important literary, scientific, and cultural knowledge; teaching strategies; motivating the acquisition and use of important conceptual knowledge and strategies; and encouraging the general tendencies supporting good information processing. Good information processing can be produced by years of appropriate educational input. Good information processors cannot be produced by short-term interventions.
We examined whether movement costs as defined by movement magnitude have an impact on distance perception in near space. In Experiment 1, participants were given a numerical cue regarding the amplitude of a hand movement to be carried out. Before the movement execution, the length of a visual distance had to be judged. These visual distances were judged to be larger, the larger the amplitude of the concurrently prepared hand movement was. In Experiment 2, in which numerical cues were merely memorized without concurrent movement planning, this general increase of distance with cue size was not observed. The results of these experiments indicate that visual perception of near space is specifically affected by the costs of planned hand movements.
Flexible behavior is only possible if contingencies between own actions and following environmental effects are acquired as quickly as possible; and recent findings indeed point toward an immediate formation of action-effect bindings already after a single coupling of an action and its effect. The present study explored whether these short-term bindings occur for both, stimulus- and goal-driven actions (“forced-choice actions” vs. “free-choice actions”). Two experiments confirmed that immediate action-effect bindings are formed for both types of actions and affect upcoming behavior. These findings support the view that action-effect binding is a ubiquitous phenomenon which occurs for any type of action.
The goal of the present study was to determine whether 4- and 5-year-old kindergarten children could be trained to maintain an organizational strategy over 2- and 8 week periods through an elaborate training program. A second goal was to assess the effects of the training program on strategy awareness. Twenty-eight kindergarten children were pretested on two sort-recall tasks and their awareness of the use of the clustering strategy was assessed through a protocol type procedure. Half the children received seven half-hour sessions of individual training in the clustering strategy and half the children participated in a control group. Both groups were post-tested on two sort-recall tasks 2 weeks following training and again 8 weeks following training. Strategy awareness, as measured by verbal protocol, was assessed at both post-test points. The elaborate strategy training program was successful in inducing short- and long-term strategy maintenance of the clustering strategy. Trained children’s clustering during sorting and clustering during recall was consistently related to the amount of items correctly recalled. No differences in strategy awareness were found. These findings demonstrate that the elaborate training procedure used in this study can be a very effective memory technique for young kindergarten children.
When a key press causes a stimulus, the key press is perceived later and the stimulus earlier than key presses and stimuli presented independently. This bias in time perception has been linked to the intention to produce the effect and thus been called intentional binding (IB). In recent studies it has been shown that the IB effect is stronger when participants believed that they caused the effect stimulus compared to when they believed that another person caused the effect (Desantis et al., 2011). In this experiment we ask whether causal beliefs influence the perceived time of an effect when the putative effect occurs temporally close to another stimulus that is also an effect. In our study two participants performed the same task on connected computers with separate screens. Each trial started synchro- nously on both computers. When a participant pressed a key, a red and a yellow stimulus appeared as action effects simultaneously or with a slight delay of up to 50 ms. The partic- ipants’ task was to judge the temporal order of these two effect stimuli. Participants were either told that one participant caused one of the two stimuli while the other participant seated at the other computer caused the other stimulus, or each participant was told that he/she caused both stimuli. The different causal beliefs changed the perceived time of the effects’ appearance relative to each other. When participants believed they each caused one effect, their “own” effect was perceived earlier than the other participant’s effect. When the participants believed each caused both effects, no difference in the perceived temporal order of the red and yellow effect was found. These results confirm that higher order causal beliefs change the perceived time of an action effect even in a setting in which the occurrence of the putative effect can be directly compared to a reference stimulus.
Nine hierarchical and four nonhierarchical clustering algorithms were compared on their ability to resolve 200 multivariate normal mixtures. The effects of coverage, similarity measures, and cluster overlap were studied by including different levels of coverage for the hierarchical algorithms, Euclidean distances and Pearson correlation coefficients, and truncated multivariate normal mixtures in the analysis. The results confirmed the findings of previous Monte Carlo studies on clustering procedures in that accuracy was inversely related to coverage, and that algorithms using correlation as the similarity measure were significantly more accurate than those using Euclidean distances. No evidence was found for the assumption that the positive effects of the use of correlation coefficients are confined to unconstrained mixture models.
A brain-computer interface (BCI) enables communication without movement based on brain signals measured with electroencephalography (EEG). BCIs usually rely on one of three types of signals: the P300 and other components of the event-related potential (ERP), steady state visual evoked potential (SSVEP), or event related desynchronization (ERD). Although P300 BCIs were introduced over twenty years ago, the past few years have seen a strong increase in P300 BCI research. This closed-loop BCI approach relies on the P300 and other components of the ERP, based on an oddball paradigm presented to the subject. In this paper, we overview the current status of P300 BCI technology, and then discuss new directions: paradigms for eliciting P300s; signal processing methods; applications; and hybrid BCIs. We conclude that P300 BCIs are quite promising, as several emerging directions have not yet been fully explored and could lead to improvements in bit rate, reliability, usability, and flexibility.
Objective: Brain-computer interfaces (BCIs) provide a non-muscular communication channel for patients with late-stage motoneuron disease (e.g., amyotrophic lateral sclerosis (ALS)) or otherwise motor impaired people and are also used for motor rehabilitation in chronic stroke. Differences in the ability to use a BCI vary from person to person and from session to session. A reliable predictor of aptitude would allow for the selection of suitable BCI paradigms. For this reason, we investigated whether P300 BCI aptitude could be predicted from a short experiment with a standard auditory oddball. Methods: Forty healthy participants performed an electroencephalography (EEG) based visual and auditory P300-BCI spelling task in a single session. In addition, prior to each session an auditory oddball was presented. Features extracted from the auditory oddball were analyzed with respect to predictive power for BCI aptitude. Results: Correlation between auditory oddball response and P300 BCI accuracy revealed a strong relationship between accuracy and N2 amplitude and the amplitude of a late ERP component between 400 and 600 ms. Interestingly, the P3 amplitude of the auditory oddball response was not correlated with accuracy. Conclusions: Event-related potentials recorded during a standard auditory oddball session moderately predict aptitude in an audiory and highly in a visual P300 BCI. The predictor will allow for faster paradigm selection. Significance: Our method will reduce strain on patients because unsuccessful training may be avoided, provided the results can be generalized to the patient population.
Thirty-two 4-year-olds and thirty-two 6-year-olds were tested for free and cued recall following either play-and-remember or sort-and-remember instructions and assessed for their metamemory of the efficacy of conceptual and perceptual sorting strategies. The younger children recalled significantly more items under sort-and-remember than under play-and-remember instructions, whereas no significant recall differences between instructional conditions were found for the older children. However, 6-year-olds showed higher levels of recall than 4-year-olds in both instructional conditions. Category cues were much more effective than color cues, regardless of age. In addition, clustering scores indicated that conceptual organization at both encoding and retrieval increased with age and with instruction. These results show that from 4 to 6 years of age children are learning to spontaneously employ memory strategies. In addition, they highlight the increasing importance of conceptual organization to retention of young children. Finally, the metamemory data suggest that there may be a lag between children’s articulated declarative knowledge about the usefulness of conceptual organization and their procedural use of it.
This article describes a 2-systems model that explains social behavior as a joint function of reflective and impulsive processes. In particular, it is assumed that social behavior is controlled by 2 interacting systems that follow different operating principles. The reflective system generates behavioral decisions that are based on knowledge about facts and values, whereas the impulsive system elicits behavior through associative links and motivational orientations. The proposed model describes how the 2 systems interact at various stages of processing, and how their outputs may determine behavior in a synergistic or antagonistic fashion. It extends previous models by integrating motivational components that allow more precise predictions of behavior. The implications of this reflective–impulsive model are applied to various phenomena from social psychology and beyond. Extending previous dual-process accounts, this model is not limited to specific domains of mental functioning and attempts to integrate cognitive, motivational, and behavioral mechanisms.
Body image disturbances are core symptoms of eating disorders (EDs). Recent evidence suggests that changes in body image may occur prior to ED onset and are not restricted to in-vivo exposure (e.g. mirror image), but also evident during presentation of abstract cues such as body shape and weight-related words. In the present study startle modulation, heart rate and subjective evaluations were examined during reading of body words and neutral words in 41 student female volunteers screened for risk of EDs. The aim was to determine if responses to body words are attributable to a general negativity bias regardless of ED risk or if activated, ED relevant negative body schemas facilitate priming of defensive responses. Heart rate and word ratings differed between body words and neutral words in the whole female sample, supporting a general processing bias for body weight and shape-related concepts in young women regardless of ED risk. Startle modulation was specifically related to eating disorder symptoms, as was indicated by significant positive correlations with self-reported body dissatisfaction. These results emphasize the relevance of examining body schema representations as a function of ED risk across different levels of responding. Peripheral-physiological measures such as the startle reflex could possibly be used as predictors of females’ risk for developing EDs in the future.
ln two experiments, male rats were observed in pairs under different environmental stimulations in an open field. ln Experiment 1, white noise of 85 dB(A) reduced social activities and increased defecation compared to 75 dB(A) and 65 dß(A). ln Experiment 2, the illumination of the open field was varied in addition to a variation of the noise intensity. Again, 85 dB(A) as compared to 50 dB(A) reduced social activities and increased defecation, but also led to changes in non-social behaviours such as sniffing, grooming, and rearing. ln contrast, 400 lx did not differ substantially in its effects from 40 lx in any of the observed behavioural categories. Altogether, the behaviour pattern under 85 dß(A) white noise cannot satisfactorily be explained only by increased anxiety or fear. Alternative explanations are discussed.
Social attention is a ubiquitous, but also enigmatic and sometimes elusive phenomenon.
We direct our gaze at other human beings to see what they are doing
and to guess their intentions, but we may also absorb social events en passant as
they unfold in the corner of the eye. We use our gaze as a discrete communication
channel, sometimes conveying pieces of information which would be difficult
to explicate, but we may also find ourselves avoiding eye-contact with others in
moments when self-disclosure is fear-laden. We experience our gaze as the most
genuine expression of our will, but research also suggests considerable levels of
predictability and automaticity in our gaze behavior. The phenomenon’s complexity
has hindered researchers from developing a unified framework which can
conclusively accommodate all of its aspects, or from even agreeing on the most
promising research methodologies.
The present work follows a multi-methods approach, taking on several aspects
of the phenomenon from various directions. Participants in study 1 viewed dynamic
social scenes on a computer screen. Here, low-level physical saliency (i.e.
color, contrast, or motion) and human heads both attracted gaze to a similar extent,
providing a comparison of two vastly different classes of gaze predictors in
direct juxtaposition. In study 2, participants with varying degrees of social anxiety
walked in a public train station while their eye movements were tracked. With
increasing levels of social anxiety, participants showed a relative avoidance of gaze
at near compared to distant people. When replicating the experiment in a laboratory
situation with a matched participant group, social anxiety did not modulate
gaze behavior, fueling the debate around appropriate experimental designs in the
field. Study 3 employed virtual reality (VR) to investigate social gaze in a complex
and immersive, but still highly controlled situation. In this situation, participants
exhibited a gaze behavior which may be more typical for real-life compared to laboratory situations as they avoided gaze contact with a virtual conspecific unless
she gazed at them. This study provided important insights into gaze behavior in
virtual social situations, helping to better estimate the possible benefits of this
new research approach. Throughout all three experiments, participants showed
consistent inter-individual differences in their gaze behavior. However, the present
work could not resolve if these differences are linked to psychologically meaningful
traits or if they instead have an epiphenomenal character.
Brain–computer interfaces (BCI) based on event-related potentials (ERP) allow for selection of characters from a visually presented character-matrix and thus provide a communica- tion channel for users with neurodegenerative disease. Although they have been topic of research for more than 20 years and were multiply proven to be a reliable communication method, BCIs are almost exclusively used in experimental settings, handled by qualified experts. This study investigates if ERP–BCIs can be handled independently by laymen without expert support, which is inevitable for establishing BCIs in end-user’s daily life situations. Furthermore we compared the classic character-by-character text entry against a predictive text entry (PTE) that directly incorporates predictive text into the character- matrix. N = 19 BCI novices handled a user-centered ERP–BCI application on their own without expert support. The software individually adjusted classifier weights and control parameters in the background, invisible to the user (auto-calibration). All participants were able to operate the software on their own and to twice correctly spell a sentence with the auto-calibrated classifier (once with PTE, once without). Our PTE increased spelling speed and, importantly, did not reduce accuracy. In sum, this study demonstrates feasi- bility of auto-calibrating ERP–BCI use, independently by laymen and the strong benefit of integrating predictive text directly into the character-matrix.
From simply ringing a bell to preparing a five-course menu, human behavior commonly causes changes in the environment. Such episodes where an agent acts, thereby causing changes in their environment constitute the sense of agency. In this thesis four series of experi-ments elucidate how the sense of agency is represented in complex action-event sequences, thereby bridging a gap between basic cognitive research and real-life practice. It builds upon extensive research on the sense of agency in unequivocal sequences consisting of single ac-tions and distinct, predominantly auditory, outcomes. Employing implicit as well as explicit measures, the scope is opened up to multi-step sequences.
The experiments show that it is worthwhile devoting more research to complex action-event sequences. With a newly introduced auditory measure (Chapter II), common phenomena such as temporal binding and a decrease in agency ratings following distorted feedback were replicated in multi-step sequences. However, diverging results between traditional implicit and explicit measures call for further inspection. Multisensory integration appears to gain more weight when multiple actions have to be performed to attain a goal leading to more accurate representations of the own actions (Chapter III). Additionally, freedom of choice (Chapter III) as well as early spatial ambiguity altered the perceived timing of outcomes, while late spatial ambi-guity (Chapter IV) and the outcome’s self-relevance did not (Chapter V). The data suggests that the cognitive system is capable of representing multi-step action-event sequences implicitly and explicitly. Actions and sensory events show a temporal attraction stemming from a bias in the perception of outcomes. Explicit knowledge about causing an event-sequence facilitates neither feelings of control nor taking authorship. The results corroborate current theorizing on the un-derpinnings of temporal binding and the divergence between traditional implicit and explicit measures of the sense of agency. Promising avenues for further research include structured analyses of how much inferred causality contributes to implicit and explicit measures of agency as well as finding alternative measures to capture conceptual as well as non-conceptual facets of the agency experience with one method.