Study of behavioural and neural bases of visuo‐spatial working memory with an fMRI paradigm based on an n‐back task

The goal of this study was to propose a new functional magnetic resonance imaging (fMRI) paradigm using a language‐free adaptation of a 2‐back working memory task to avoid cultural and educational bias. We additionally provide an index of the validity of the proposed paradigm and test whether the experimental task discriminates the behavioural performances of healthy participants from those of individuals with working memory deficits. Ten healthy participants and nine patients presenting working memory (WM) deficits due to acquired brain injury (ABI) performed the developed task. To inspect whether the paradigm activates brain areas typically involved in visual working memory (VWM), brain activation of the healthy participants was assessed with fMRIs. To examine the task's capacity to discriminate behavioural data, performances of the healthy participants in the task were compared with those of ABI patients. Data were analysed with GLM‐based random effects procedures and t‐tests. We found an increase of the BOLD signal in the specialized areas of VWM. Concerning behavioural performances, healthy participants showed the predicted pattern of more hits, less omissions and a tendency for fewer false alarms, more self‐corrected responses, and faster reaction times, when compared with subjects presenting WM impairments. The results suggest that this task activates brain areas involved in VWM and discriminates behavioural performances of clinical and non‐clinical groups. It can thus be used as a research methodology for behavioural and neuroimaging studies of VWM in block‐design paradigms.     

Ankle Intrinsic Stiffness in Subcortical Poststroke Subjects

The authors' purpose was to evaluate bilateral ankle intrinsic stiffness in subcortical poststroke subjects. Ten subcortical poststroke subjects and 10 healthy controls participated in this study. The ankle passive stiffness at 3 different speeds and the electromyographic activity of the soleus, the gastrocnemius, and the tibialis anterior muscles of poststroke contralesional (CONTRA) and ipsilesional (IPSI) limbs and of one limb of healthy subjects were assessed. Ankle electromyographic activity was collected to ensure that reflexive or voluntary muscle activity was not being elicited during the passive movements. A significant interaction was observed between the effects of the limb (IPSI vs. CONTRA vs. control) and ankle position, F(4, 28) = 3.285, p = .025, and between the effects of the limb and the velocity of stretch, F(2, 14) = 4.209, p = .037. While increased intrinsic stiffness was observed in the CONTRA limb of poststroke subjects at ankle neutral position when the passive stretch was applied with a velocity of 1°/s (p = .021), the IPSI limb of poststroke subjects presented increased stiffness at 20º of plantar flexion when the stretch was applied with a velocity of 5°/s (p = .009) when compared to healthy group. Subcortical poststroke subjects present increased intrinsic stiffness in both the CONTRA and IPSI limbs in specific ankle amplitudes.     

The Origins of Fears of Compassion: Shame and Lack of Safeness Memories,Fears of Compassion and Psychopathology

Empirical and clinical research suggests that some individuals find self-generating compassion and receiving compassion from others difficult and aversive. However, it is unclear how these fears of compassion are linked to early experiences and to psychopathological symptoms. This study explores the relationship between shame traumatic memories, centrality of shame memories, early memories of warmth and safeness, fears of compassion, and depression, anxiety and paranoid symptoms. Participants were 302 individuals from the general community population, who completed self-report measures of fears of compassion, shame memories, early affiliative memories, and psychopathology. Shame traumatic and central memories were positively associated with fears of compassion for self, for others and from others, whereas early memories of warmth and safeness were negatively related to such fears. Path analyses revealed that fears of compassion for self and of receiving compassion from others mediated the effects of shame traumatic memory, centrality of shame memory and early memories of warmth and safeness on depressive, anxious and paranoid symptoms. These findings have implications for therapeutic interventions as these fears, as well as the negative shame-based emotional memories fuelling them, may need to be addressed in therapy to assist patients in self-generating and receiving compassion.     

A Direct-Learning Approach to Acquiring a Bimanual Tapping Skill

The theory of direct learning (D. M. Jacobs &; C. F. Michaels, 2007 Jacobs, D. M., &; Michaels, C. F. (2007). Direct learning. Ecological Psychology, 19, 321–349.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) has proven useful in understanding improvement in perception and exploratory action. Here the authors assess its usefulness for understanding the learning of a motor skill, bimanual tapping at a difficult phase relation. Twenty participants attempted to learn to tap with 2 index fingers at 2 Hz with a phase lag of 90° (i.e., with a right-right period of 500 ms and a right-left period of 125 ms). There were 30 trials, each with 50 tapping cycles. Computer-screen feedback informed of errors in both period and phase for each pair of taps. Participants differed dramatically in their success. Learning was assessed by identifying the succession of attractors capturing tapping over the experiment. A few participants’ attractors migrated from antiphase to 90° with an appropriate period; others became attracted to a fixed right-left interval, rather than phase, with or without attraction to period. Changes in attractor loci were explained with mixed success by direct learning, inviting elaboration of the theory. The transition to interval attractors was understood as a change in intention, and was remarkable for its indifference to typical bimanual interactions.     

Nonconceptualism,Hume’s Problem,and the Deduction

Lucy Allais seeks to provide a reading of the Transcendental Deduction of the Categories which is compatible with a nonconceptualist account of Kant’s theory of intuition. According to her interpretation, the aim of the Deduction is to show that a priori concept application is required for empirical concept application. I argue that once we distinguish the application of the categories from the instantiation of the categories, we see that Allais’s reconstruction of the Deduction cannot provide an answer to Hume’s problem about our entitlement to use a priori concepts when thinking about the objects of empirical intuition. If the Deduction is to provide a response to Hume, Allais’s interpretation must be rejected.     

Loving styles: relationships with personality and attachment styles

We investigated the ability of the major personality dimensions, some of their underlying facet scales, and attachment styles to predict primary and secondary loving styles, as conceptualized by Lee. Personality was assessed using the International Personality Item Pool, and attachment styles through an inventory devised by Collins and Read. Respondents were 302 undergraduate students (212 females; 90 males) who participated in the study in exchange for course credit. Results of regression path analysis showed that N was the only personality dimension without direct predictive links to loving styles. Instead, the influence of N was through an anxious attachment style. There were no personality predictors of Agape, and similarities were also observed between these results and those obtained in Hong Kong. The results are discussed with reference to previous studies and some suggestions for further research are also noted. Copyright © 2003 John Wiley & Sons, Ltd.     

Planning and articulation in incremental word production: syllable-frequency effects in English

We investigated the role of syllables during speech planning in English by measuring syllable-frequency effects. So far, syllable-frequency effects in English have not been reported. English has poorly defined syllable boundaries, and thus the syllable might not function as a prominent unit in English speech production. Speakers produced either monosyllabic (Experiment 1) or disyllabic (Experiment 2-4) pseudowords as quickly as possible in response to symbolic cues. Monosyllabic targets consisted of either high- or low-frequency syllables, whereas disyllabic items contained either a 1st or 2nd syllable that was frequency-manipulated. Significant syllable-frequency effects were found in all experiments. Whereas previous findings for disyllables in Dutch and Spanish-languages with relatively clear syllable boundaries-showed effects of a frequency manipulation on 1st but not 2nd syllables, in our study English speakers were sensitive to the frequency of both syllables. We interpret this sensitivity as an indication that the production of English has more extensive planning scopes at the interface of phonetic encoding and articulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved).