Time perception and the internal clock: Effects of visual flicker on the temporal oscillator

Abstract

Our ability to estimate time intervals has sometimes been attributed to a biological source of temporal information. A model for a temporal oscillator that provides such information has recently been described (Treisman, Faulkner, Naish & Brogan, 1990). This predicts that an imposed stimulus rhythm at certain frequencies may interfere with the temporal oscillator so as to alter its frequency. This interference would cause perturbations in temporal judgements at certain frequencies of the imposed rhythm. The pattern of interference would depend on the frequency at which the temporal oscillator runs, and so would contain information about the oscillator frequency. Evidence for such a pattern was found when auditory clicks at different rates were presented concurrently with time intervals whose durations subjects estimated. The present study examines whether a similar interference pattern can be obtained if visual flicker is substituted for auditory clicks. On each trial, flicker was presented at a rate between 2.5 and 17.5 Hz, concurrently with a time interval to be estimated. A pattern of increased estimates at some rates and decreased estimates at others was obtained. This pattern showed similarities to interference patterns obtained using auditory clicks. This provides evidence that the entrainment of the internal clock predicted by the model can also be produced by visual inputs. Other theoretical implications are discussed.     

Implementation of outpatient schema therapy for borderline personality disorder with versus without crisis support by the therapist outside office hours: A randomized trial

Objective

This study aimed to evaluate the success of implementing outpatient schema focused therapy (ST) for borderline patients in regular mental healthcare and to determine the added value of therapist telephone availability outside office hours in case of crisis (TTA).

Methods

To enhance the implementation, the following adaptations regarding the original ST protocol were applied: a reduction in the frequency and duration of the therapy; training therapists of eight regular healthcare centers in ST with a structured and piloted program supported by a set of films (DVDs) with examples of ST techniques; training and supervision given by Dutch experts. Telephone availability outside office hours was randomly allocated to 50% of the therapists of each treatment center. Patient's outcome measures were assessed with a semi-structured interview and self-report measures on BPD, quality of life, general psychopathology and an ST questionnaire, before, during and after treatment.

Results

Data on 62 DSM-IV defined BPD patients were available. Intention-to-treat analyses showed that after 1.5 years of ST 42% of the patients had recovered from BPD.No added value of therapist telephone availability (TTA) was found on the BPDSI score nor on any other measure after 1.5 years of ST.

Conclusions

ST for BPD can be successfully implemented in regular mental healthcare. Treatment results and dropout were comparable to a previous clinical trail. No additional effect of extra crisis support with TTA outside office hours ST was found.     

Predictors and outcomes of joint trajectories of callous-unemotional traits and conduct problems in childhood

Callous-unemotional (CU) traits are associated with antisocial and delinquent behaviors in children and represent a potential risk factor for adult psychopathy. However, there is a paucity of longitudinal research that explores the development of these traits, their longitudinal association with conduct problems (CP), and their psychosocial predictors and outcomes. Using a large sample of children followed longitudinally from the Twins Early Development Study (N=9,578), we described the joint developmental trajectories of CU traits and CP during childhood (between ages 7 and 12) and examined the child- and family-level predictors (4 years old) and concomitant outcomes (12 years old) associated with the trajectories. The developmental trajectories were characterized with teachers' ratings of CU traits and CP from ages 7 to 12. Using general growth mixture modeling, we identified four trajectories of CU traits (stable high, increasing, decreasing, and stable low) and two trajectories of CP (high and low). Compared with the children who followed a low trajectory of CU traits and CP, those who followed a high trajectory of CU traits and CP had more negative child- and family-level predictors at 4 years (including CP, hyperactivity, negative parental discipline, and chaos in the home). Children with high or increasing levels of CU traits and concomitant high levels of CP presented the most negative outcomes at 12 years (including hyperactivity, peer problems, emotional problems, and negative parental feelings). Children with high CU traits and concomitant high levels of CP in childhood should be prioritized for targeted intervention.     

PKA and PKC are required for long-term but not short-term in vivo operant memory in Aplysia

We investigated the involvement of PKA and PKC signaling in a negatively reinforced operant learning paradigm in Aplysia, learning that food is inedible (LFI). In vivo injection of PKA or PKC inhibitors blocked long-term LFI memory formation. Moreover, a persistent phase of PKA activity, although not PKC activity, was necessary for long-term memory. Surprisingly, neither PKA nor PKC activity was required for associative short-term LFI memory. Additionally, PKA and PKC were not required for the retrieval of short- or long-term memory (STM and LTM, respectively). These studies have identified key differences between the mechanisms underlying nonassociative sensitization, operant reward learning, and LFI memory in Aplysia.     

For a psycholinguistic model of handwriting production: testing the syllable-bigram controversy

This study examined the theoretical controversy on the impact of syllables and bigrams in handwriting production. French children and adults wrote words on a digitizer so that we could collect data on the local, online processing of handwriting production. The words differed in the position of the lowest frequency bigram. In one condition, it coincided with the word's syllable boundary. In the other condition, it was located before the syllable boundary. The results yielded higher movement durations at the position where the low-frequency bigram coincided with the syllable boundary compared to where the low-frequency bigram appeared before the syllable boundary. Syllable-oriented strategies failed with the presence of a very low-frequency bigram within the initial syllable. Further analysis showed that children in grades 3 and 4 privileged syllable-oriented programming strategies. The production times of children in grade 4 were also affected by syllable frequency and, to a lesser extent, bigram frequency. The adults writing durations were modulated by bigram frequency. Therefore, both bigrams and syllables regulate handwriting production although the influence of bigrams was stronger in adults than children. In the light of these results, we propose a psycholinguistic model of handwriting production.     

Justified ethicality: Observing desired counterfactuals modifies ethical perceptions and behavior

Employing a die-under-cup paradigm, we study the extent to which people lie when it is transparently clear they cannot be caught. We asked participants to report the outcome of a private die roll and gain money according to their reports. Results suggest that the degree of lying depends on the extent to which self-justifications are available. Specifically, when people are allowed to roll the die three times to ensure its legitimacy, but only the first roll is supposed to “count,” we find evidence that the highest outcome of the three rolls is reported. Eliminating the ability to observe more than one roll reduces lying. Additional results suggest that observing desired counterfactuals, in the form of additional rolls not meant to determine pay, attenuates the degree to which people perceive lies as unethical. People seem to derive value from self-justifications allowing them to lie for money while feeling honest.     

Sous un même toit: Canada's Functional-Structural Approach to the Unity of Psychology

Among the factors which may be useful to an assessment of unity/diversity, several are germane to the historic and contemporary evolution of psychology in Canada. Culture-based variables, economic and political factors, and the emergence of clearly scientific and professional streams are all pertinent to Canadian psychology. Within this context, Rosenzweig's (this issue) conceptualization of internal/external unifying/diversifying forces facilitates a better understanding of the realities which confront Canadian psychologists. By adopting a collaborative, collegially oriented approach with diverse groups spawning the full spectrum of psychological science and practice, the groundwork has been laid for a confederal system of functionally based cooperation which may be sufficient to maintain cohesion within the Canadian context.     

The metrics of spatial distance traversed during mental imagery

The authors conducted 2 experiments to study the metrics of spatial distance in a mental imagery task. In both experiments, participants first memorized the layout of a building containing 10 rooms with 24 objects. Participants then received mental imagery instructions and imagined how they walked through the building from one room to another. The authors manipulated Euclidean distance involved in these imaginary motions: Spatial distance measured in centimeters on the layout was either short or long. Independently, they varied categorical distance: The motions led through one room or two rooms. The time needed to imagine motions and response times to test probes indicated that both Euclidean distance and categorical distance affected mental imagery. The authors discuss the new finding of categorical distance effects in mental imagery and relate the results to earlier failures to find Euclidean distance effects in formally equivalent studies of narrative comprehension.     

Beyond objectivity: The performance impact of the perceived ability to learn and solve problems

The purpose of this research was to develop and provide initial validation evidence for the performance impact of a measure of an individual's perceived ability to learn and solve problems (PALS). Building on the self-efficacy literature and the importance of learning and problem solving, the fundamental premise of this research was that PALS would significantly explain employee performance. In addition to demonstrating that PALS represented a distinct construct, PALS was a significant predictor of performance for managerial and entry-level employees in two different organizational contexts. Moreover, PALS explained additional variance in performance beyond general mental ability, personality, and similar constructs related to learning and problem solving.     

Left-handedness and male-male competition: Insights from fighting and hormonal data

Male-male competition can shape some behavioral or morphological traits of males. Here we investigate if this competition could play a role in the persistence of the polymorphism of handedness in human populations. A negative frequency-dependent selection mechanism has been hypothesized, based on the fact that left-handed men may benefit from a "surprise" advantage during fighting interactions because they are rare in human populations. This advantage may thereby enhance the probability of survival of left- handed men and/or their reproductive success through an increase in social status. In this study, we first explored the association between hand preference and lifetime fighting behavior in a population of 1,161 French men. No effect of hand preference on the probability of fighting was detected, suggesting that the innate propensity to fight does not differ between left- and right-handers. However, among men who had been involved in at least one fight during their lifetime, left-handers reported significantly more fights than right-handers. To explore the biological basis of this behavior, we also investigated the testosterone concentration in saliva samples from 64 French university students. Consistent with frequencies of fights, we found a significantly higher average testosterone concentration in left-handers than in right-handers. We suggest that these behavioral and hormonal differences may be acquired throughout life due to previous experiences in a social context and may favor the persistence of left-handers in humans.