Contemporary theories of 1/f noise in motor control

1/f noise has been discovered in a number of time series collected in psychological and behavioral experiments. This ubiquitous phenomenon has been ignored for a long time and classical models were not designed for accounting for these long-range correlations. The aim of this paper is to present and discuss contrasted theoretical perspectives on 1/f noise, in order to provide a comprehensive overview of current debates in this domain. In a first part, we propose a formal definition of the phenomenon of 1/f noise, and we present some commonly used methods for measuring long-range correlations in time series. In a second part, we develop a theoretical position that considers 1/f noise as the hallmark of system complexity. From this point of view, 1/f noise emerges from the coordination of the many elements that compose the system. In a third part, we present a theoretical counterpoint suggesting that 1/f noise could emerge from localized sources within the system. In conclusion, we try to draw some lines of reasoning for going beyond the opposition between these two approaches.     

Test-retest reliability of the Frankfurt Complaint Questionnaire

Long-term reliability of the Frankfurt Complaint Questionnaire (FCQ) was investigated in two follow-up studies of participants with psychosis using a test-retest method. In the first study (N = 56), the duration of the follow-up ranged from 6 months to 2 years; Spearman rho was .62 for the abridged (18 items) Spanish version of the questionnaire. In Study 2 (N = 21), in participants with stable schizophrenia, the follow-up ranged from 8 to 11 years; test-retest Spearman rho was .83 for the French version of the questionnaire. Subjective experiences could constitute, in psychosis-prone people, traits or markers of psychotic vulnerability.     

The role of goal representation in preschoolers' flexibility and inhibition

This study addressed the role of goal representation in preschoolers’ inhibition and flexibility performance. A total of 56 4- and 5-year-olds were tested in an adapted version of the Shape School task where the difficulty of goal representation was manipulated by varying the degree of transparency of task cues. The findings showed that both age groups’ performance in the flexibility phase was increased when demands on goal representation were alleviated by using transparent cues instead of arbitrary cues. Furthermore, 4-year-olds performed more accurately on go trials in the inhibition phase with transparent cues than with arbitrary cues. These results confirm the critical role of goal representation in flexibility and reveal its influence in inhibition contexts. Altogether, this study suggests that goal representation is a key element for efficient executive function across a variety of settings involving different executive functions.     

The influence of stimulus-set size on developmental changes in cognitive control and conflict adaptation

Cognitive control abilities substantially improve from early childhood to adulthood. The primary aim of this study was to examine the influence of stimulus-set size on developmental changes in cognitive control abilities such as task switching, interference control, and conflict adaptation. We assumed that a small stimulus set used in a task-switching paradigm would induce stronger task-stimulus priming that might increase the need for control, thereby amplifying age differences in cognitive control abilities. Therefore, we compared task-switching performance in a group of participants responding to a small stimulus-set (N=4) with a group responding to a large stimulus-set (N=96) in three age groups: kindergarten children (4.1-6.0 years of age), elementary school children (6.1-9.0 years of age), and young adults (21.0-28.0 years of age) on conflicting vs. non-conflicting trials (interference control) and following conflicting vs. non-conflicting trials (conflict adaptation). Results on the basis of error rates support the view that a small stimulus-set size during task switching (i.e., larger task-stimulus priming) increases the need for control as we found (a) worse conflict adaptation on task-repetition trials only for small but not for large set sizes and (b) larger interference costs under small than large set-size condition for elementary school children as compared with young adults. Kindergarten children were less sensitive to the set-size manipulation and showed major problems in interference control while being in a task-switching situation, even if no actual task switch was required, possibly reflecting their inability to represent complex higher-order task rules.     

Validating an interlingual metanorm for emotional analysis of texts

In this article, we present a set of 12 norms that characterize emotional terms in French, English, German, Spanish, Italian, and Finnish. The high correlation between the norm values in the two emotional dimensions of valence and arousal suggests an interlingual homogeneity of emotional representations and allows a significant metanorm??EMONORM??to be established with 6,383 terms characterized in valence and 4,345 terms characterized in arousal. This metanorm is a resource for creating experimental materials in studies on language and emotions. Furthermore, we perform three tests using EMONORM, with the objectives of (1) identifying basic emotions from their valence and arousal values, (2) determining the orientation of texts referring to positive and negative emotions, and (3) evaluating the intensity of emotions expressed in texts. The results are highly similar to those for human judgments. Finally, we present EMOVAL/SEMOTEX, a Web application for static and dynamic valence and arousal emotional analysis of texts using EMONORM (http://www.semotex.fr).     

Temporal dynamics of activation of thematic and functional knowledge during conceptual processing of manipulable artifacts

The current research aimed at specifying the activation time course of different types of semantic information during object conceptual processing and the effect of context on this time course. We distinguished between thematic and functional knowledge and the specificity of functional similarity. Two experiments were conducted with healthy older adults using eye tracking in a word-to-picture matching task. The time course of gaze fixations was used to assess activation of distractor objects during the identification of manipulable artifact targets (e.g., broom). Distractors were (a) thematically related (e.g., dustpan), (b) related by a specific function (e.g., vacuum cleaner), or (c) related by a general function (e.g., sponge). Growth curve analyses were used to assess competition effects when target words were presented in isolation (Experiment 1) and embedded in contextual sentences of different generality levels (Experiment 2). In the absence of context, there was earlier and shorter lasting activation of thematically related as compared to functionally related objects. The time course difference was more pronounced for general functions than specific functions. When contexts were provided, functional similarities that were congruent with context generality level increased in salience with earlier activation of those objects. Context had little impact on thematic activation time course. These data demonstrate that processing a single manipulable artifact concept implicitly activates thematic and functional knowledge with different time courses and that context speeds activation of context-congruent functional similarity. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

What lies behind postnatal depression: is it only a mood disorder?

Postnatal depression (PND) is a common condition that has been extensively researched specifically because of its negative impact on the mother-infant relationship. Psychiatric research has looked at comorbidity of major depressive disorder and found it to be strongly associated with Axis II disorders. This study's principal aim was to investigate whether there is a greater incidence of personality disorder (PD) among a PND population than among a non-PND population at 3 months postpartum. A secondary aim was to define the different types of PD. Depression was assessed with the Montgomery and Asberg Depression Rating Scale (MADRS), and PD was assessed with the Structured Interview for DSM-IV Personality Disorders (SIDP-IV) in 109 women with their 12-week-old infants. Twice as many depressed mothers had PD. The PND group presented a greater number of severe clinical symptoms than the nondepressed group (p < .002). Further research is necessary to reexamine the heterogeneity of PND and reassess its impact on infant development.     

Expression of nonconscious knowledge via ideomotor actions

Ideomotor actions are behaviours that are unconsciously initiated and express a thought rather than a response to a sensory stimulus. The question examined here is whether ideomotor actions can also express nonconscious knowledge. We investigated this via the use of implicit long-term semantic memory, which is not available to conscious recall. We compared accuracy of answers to yes/no questions using both volitional report and ideomotor response (Ouija board response). Results show that when participants believed they knew the answer, responses in the two modalities were similar. But when they believed they were guessing, accuracy was at chance for volitional report (50%), but significantly higher for Ouija response (65%). These results indicate that implicit semantic memory can be expressed through ideomotor actions. They also suggest that this approach can provide an interesting new methodology for studying implicit processes in cognition.