Fitts' Law is Applicable to Trunk Coordination Measurements in a Sitting Position

Trunk coordination is essential for many activities of daily living in wheelchair users. This study investigated whether Fitts' law is applicable to trunk movements in a sitting position. Fourteen healthy adults performed two series of 24 tasks of trunk flexion–extension movements in a sitting position. The results showed significant linear relationships between average group movement time (MT) and index of difficulty (ID) over all tasks (r² = 0.92) and within target distances (0.94 < r² < 1.00). Target distance affected intercept and slope (P < 0.001). Hence, Fitts' law is applicable to the studied trunk movements in a sitting position, indicating these trunk movements tasks could serve as a basis for qualitative trunk coordination tests. Transferability of these conclusions to wheelchair users, and optimal test design should be further investigated.     

More expertise for a better perspective: Task and strategy-driven adaptive neurofunctional reorganization for word production in high-performing older adults

The suggestion that neurofunctional reorganization may contribute to preserved language abilities is still emerging in aging studies. Some of these abilities, such as verbal fluency (VF), are not unitary but instead rely on different strategic processes that are differentially changed with age. Younger (n = 13) and older adults (n = 13) carried out an overt self-paced semantic and orthographic VF tasks within mixed fMRI design. Our results suggest that patterns of brain activation sustaining equivalent performances could be underpinned by different strategies facing brain changes during healthy aging. These main findings suggest that temporally mediated semantic clustering and frontally mediated orthographic switching were driven by evolutive neurofunctional resources in high-performing older adults. These age-related activation changes can appear to be compatible with the idea that unique neural patterns expressing distinctive cognitive strategies are necessary to support older adults’ performance on VF tasks.     

The time course of access to semantic information in high-performing older adults: behavioral evidence for the hemispheric asymmetry reduction in OLDer individuals

The possibility that the HAROLD phenomenon (i.e., Hemispheric Asymmetry Reduction in OLDer adults) is manifested in the course of access to semantic information, in particular the meaning of emotional words, was investigated using the visual half-field priming paradigm. The time course of priming was tracked in the cerebral hemispheres across three SOAs: 150, 300, and 750 ms. The results showed older and young adults had the same level of accuracy. While priming occurred unilaterally in young participants, the pattern of priming in older participants appeared to be bilateral whenever it was present, that is, at the 300- and 750-ms SOAs. The delay in the appearance of priming in older adults may be due to an increase in sensory thresholds that causes older adults to need more time to encode stimuli and fully activate their semantic network. It is concluded that the bilateral pattern of priming in the presence of an equivalent level of performance in older adults provides behavioral evidence supporting the compensatory role of the HAROLD phenomenon for this particular task.     

A study of EEG coherence in DCD children during motor synchronization task

This paper investigates the hypothesis that the coordination difficulties of DCD children are associated with an increased coherence in the cortical motor regions, which persists with age. Forty-eight children participated in the study (24 DCD and 24 Controls). Their ages ranged from 8 to 13 years, divided into three groups (8-9, 10-11, and 12-13 years old). Children were required to perform finger flexion or extension either in synchrony or in syncopation with a rhythmic metronome, while a 32-channel EEG was recorded. Along with stability measures of motor performance, we analyzed the spectral EEG coherence between intrahemispheric (left frontal/left central; left central/left parietal) and interhemispheric (left central/right central) sites. Spectral coherence assesses functional coupling between distant areas of the brain. Two frequency bands related to sensorimotor activation were chosen: alpha (8-12 Hz) and beta (12-30 Hz). The synchrony task was chosen as a rest condition against which the two syncopation conditions at 0.5 Hz and 1.3 Hz were contrasted. For intrahemispheric comparison, 8-9-year-old DCD children showed that coherence between fronto-central regions increased for both rhythms and conditions, as compared to controls. No difference was found for interhemispheric comparisons. As frontal sites are related to motor planning, our results suggest that youngest DCD children were forced to maintain a high level of pre-programming to compensate for the difficulties caused by the perceptual-motor requirements of the task in light of their coordination disorder.     

Cortical regions activated by the subjective sense of perceptual coherence of environmental sounds: A proposal for a neuroscience of intuition

According to the Oxford English Dictionary, intuition is “the ability to understand or know something immediately, without conscious reasoning.” In other words, people continuously, without conscious attention, recognize patterns in the stream of sensations that impinge upon them. The result is a vague perception of coherence, which subsequently biases thought and behavior accordingly. Within the visual domain, research using paradigms with difficult recognition has suggested that the orbitofrontal cortex (OFC) serves as a fast detector and predictor of potential content that utilizes coarse facets of the input. To investigate whether the OFC is crucial in biasing task-specific processing, and hence subserves intuitive judgments in various modalities, we used a difficult-recognition paradigm in the auditory domain. Participants were presented with short sequences of distorted, nonverbal, environmental sounds and had to perform a sound categorization task. Imaging results revealed rostral medial OFC activation for such auditory intuitive coherence judgments. By means of a conjunction analysis between the present results and those from a previous study on visual intuitive coherence judgments, the rostral medial OFC was shown to be activated via both modalities. We conclude that rostral OFC activation during intuitive coherence judgments subserves the detection of potential content on the basis of only coarse facets of the input.     

Exaggerated leftward bias in the mental number line of patients with schizophrenia

Several visuo-motor tasks can be used to demonstrate biases towards left hemispace in schizophrenic patients, suggesting a minor right hemineglect. Recent studies in neglect patients used a new number bisection task to highlight a lateralized defect in their visuo-spatial representation of numbers. To test a possible lateralized representational deficit in schizophrenia, we used the number bisection task in 11 schizophrenic patients compared to 11 healthy controls. Participants were required to orally indicate the central number of an interval orally presented. Whereas healthy subjects showed no significant bias, schizophrenic patients presented a significant leftward bias. Therefore, these results suggest an impairment in higher order representations of the number space in patients with schizophrenia, an impairment that is qualitatively similar to the deficit described in neglect patients.     

Is absolute identification always relative? Comment on Stewart, Brown, and Chater (2005)

N. Stewart, G. D. A. Brown, and N. Chater's relative judgment model includes three core assumptions that enable it to predict accurately the vast majority of "classical" phenomena in absolute identification choices, but not the time taken to make them, including sequential effects, such as assimilation and contrast. These core assumptions, coupled with the parameter values used in the above-mentioned article, lead to the prediction that identification accuracy is low when a large stimulus on 1 trial is followed by a small stimulus on the next trial and vice versa. Data do not support this prediction. The authors identify a set of parameters that allow the model to better fit the data, but problems remain when the data are analyzed with a version of the discrimination measure (d') from signal detection theory. The fundamental problem is that the model fits data on average but at the expense of making incorrect predictions in detail.     

Beyond positive and negative affect: Achievement goals and discrete emotions in the elementary physical education classroom

ObjectivesBased on the Achievement Goal perspective [Dweck, C. S., Leggett, E. L. (1988). A social-cognitive approach to motivation and personality. Psychological Review, 95, 256–273; Nicholls, J. G. (1984). Achievement motivation: conceptions of ability, subjective experience, task choice, and performance. Psychological Review, 91, 328–346] and on Pekrun et al.'s [(2004). Beyond test anxiety: development and validation of the test emotions questionnaire (TEQ). Anxiety, Stress, and Coping, 17, 287–316] model of discrete class-related emotions, this study investigated the relation of achievement goals to discrete emotions in the Physical Education (PE) class.DesignCross-sectional.MethodParticipants were 319 Greek upper elementary school students who responded to a set of questionnaires assessing their achievement goal orientation, perceived competence, and the class-related emotions they experienced in the PE classes.ResultsHierarchical regression analyses showed that, after controlling for perceived competence and gender differences, task goals were positively related to positive activating emotions and negatively related to negative emotions. Ego goals exhibited a mixed picture as they were positively associated with pride and all the negative emotions. Furthermore, the relations between ego goals and emotions were qualified by an ego by task goal and by an ego by perceived competence interaction suggesting that ego goals were especially linked to emotional maladjustment when task goals were low and when competence perceptions were high rather than low.ConclusionUnique associations between task and ego goals and specific emotions were found, rendering insightful the disentanglement of positive and negative emotions into its components. The pursuit of task goals might help to counteract the emotional burden associated with ego goal pursuit whereas feeling competent to outperform when one endorses ego goals might perhaps put extra pressure on the pupils and, hence, have negative implications for their emotional adjustment.     

The inhibitory avoidance test optimized for discovery of cognitive enhancers

In the present article, we describe a new protocol for the inhibitory avoidance test, with a dual purpose: (1) to provide a leß variable and more reliable aßeßment of the efficacy of potential cognitive enhancers in antagonizing scopolamine-induced long-term-memory deficits, and (2) to secure a high throughput for pharmacological screening of cognitive enhancers. The new protocol consists of two acquisition trials that are followed 24 h later by a single retention trial. In the present study, this protocol clearly dißociated the frequency distributions of retention latencies between scopolamine- and vehicle-treated groups and allowed validation by means of two acetylcholinesterase inhibitors—tacrine and donepezil—that proved to be active in counteracting the scopolamine-induced memory deficit. This protocol also produced stability of the behavioral response to pharmacological agents over a 3-year period. A statistical power analysis indicated that, depending on the efficacy of the drug/dose, a sample size of 5–12 mice was required in order to show a reversal of the scopolamineinduced memory deficit. The double-trial acquisition protocol is suitable for testing cognitive enhancers, while also providing a clearly enhanced throughput.