Arm-tracking performance with and without visual feedback in children and adults: developmental changes

Tracking performance was investigated in children (aged 6-7 and 10-11) and in adult subjects. Target signals, moving unpredictably along a straight line, were tracked with the preferred arm, alternately with and without visual feedback. Qualitative observations indicate that tracking is based on continuous adjustments of the ongoing response to the continuously changing target position. No step-and-hold strategy could be detected in any of the three age groups. Tracking performance was described with four simple parameters, derived from linear systems analysis: (a) the delay between target signal and tracking movement (DL); (b) performance at the low-frequency range (LF), (c) performance at the high-frequency range (HF); and (d) a measure of tracking quality or overall similarity in the shape of target signal and tracking movement (Q). There was a considerable improvement in tracking performance with age, even after the age of 10-11, which was mainly demonstrated by a decrease in DL and increases in HF and Q. Tracking performance decreased only to a small extent when visual feedback was withdrawn. Age-related differences in the contribution of visual feedback to tracking performance could not be demonstrated.     

Modification of muscle activation patterns during fast goal-directed arm movements

The motor programming of fast goal-directed arm movements was studied in a tracking task. A target jumped once or twice randomly to the left or right direction with an interstimulus interval (ISI) in a range between 50 and 125 msec. Double step stimuli were either two steps in the same direction (C-trial) or in opposite direction (R-trial). Tracking results show that at the beginning average EMG-activity is the same for responses to single step trials, R-trials and C-trials. Differences set in after some time equal to or somewhat shorter than ISI. It was concluded that muscle activation patterns of fast goal-directed movements are not preprogrammed but that they can be modified during the movement. The time interval between second target step and the moment when EMG activity of the double step response deviates from the EMG activity of a single step (RT2) could be smaller than the time interval between first target displacement and EMG onset. (RT1). If modification of the muscle activation pattern required a longer or larger activation of the active muscle, RT2 tended to be smaller than RT1, whereas RT2 was about equal to RT1 if the new muscle activation required a termination of the ongoing muscle activation pattern and the activation of another muscle.     

Stiffness as a control variable in motor performance

In the experiments described in this article we investigated the control of stiffness of the effector system in relation to parameters of the movement. If the velocity of a movement is chosen, it appears that at the same time the stiffness of the effector system is set to a preferred value. By changing the instruction given to the subject it is possible to change the relationship between velocity and stiffness without changing the kinematic parameters of the movement.Finally, the changes of stiffness and velocity in a learning process are studied. In conformity with what might be expected on intuitive grounds, it is found that velocity increases spontaneously during learning while stiffness decreases. The results are discussed in connection with the generation of motor programmes.     

Adaptive Testing

An adaptive test tailors the difficulty of the items to the ability of the examinee being tested. This article describes the general principles and models of adaptive testing beginning with the early Binet tests and continuing through state-of-the-art techniques. Such computerised adaptive tests (C.A.T.s), based on item response theory (I.R.T.), are useful both for measurement and classification applications. I.R.T. provides a means by which different sets of items, as administered in a C.A.T., can be scored on a common scale. The principal advantages of CAT. are efficiency and control over either the precision of measurement or the accuracy of classification. C.A.T. procedures can be easily implemented without writing programs using commercially available software (e.g. MicroCAT).
Un test "adaptatif" accorde la difficulté des items à la capacityé des candidate aux tests. Cet article décrit les principes généraux et les modèles de tests "adaptatifs" depuis les tests de Binet jusqu'aux techniques de pointe actuelles. Tels tests informatisés (C.A.T.s), basés sur la théorie des réponses par item (I.R.T.), sont utiles à la fois pour la mesure et la classification. I.R.T. procure les moyens par lesquels différents sets ďitems, tels qu'ils sont administrés dans un C.A.T., peuvent être notés sur une échelle commune. Les principaux avantages du C.A.T. sont ľefficacité et le contrôle de la précision de la mesure et de la fidélité de la classification. Le protocole du C.A.T. peut être aisément utilisé sans texte écrit en se servant des programmes informatisés disponibles dans le commerce.     

Investigation into Complementary and Integrative Health Approaches for Turkish Patients with Gastrointestinal Cancer

Journal of Religion and Health - The study was conducted to determine the levels of usage of complementary and integrative health (CIH) approaches and the symptoms experienced by Turkish patients...     

Response–reinforcer dependency and resistance to change

The effects of the response–reinforcer dependency on resistance to change were studied in three experiments with rats. In Experiment 1, lever pressing produced reinforcers at similar rates after variable interreinforcer intervals in each component of a two‐component multiple schedule. Across conditions, in the fixed component, all reinforcers were response‐dependent; in the alternative component, the percentage of response‐dependent reinforcers was 100, 50 (i.e., 50% response‐dependent and 50% response‐independent) or 10% (i.e., 10% response‐dependent and 90% response‐independent). Resistance to extinction was greater in the alternative than in the fixed component when the dependency in the former was 10%, but was similar between components when this dependency was 100 or 50%. In Experiment 2, a three‐component multiple schedule was used. The dependency was 100% in one component and 10% in the other two. The 10% components differed on how reinforcers were programmed. In one component, as in Experiment 1, a reinforcer had to be collected before the scheduling of other response‐dependent or independent reinforcers. In the other component, response‐dependent and ‐independent reinforcers were programmed by superimposing a variable‐time schedule on an independent variable‐interval schedule. Regardless of the procedure used to program the dependency, resistance to extinction was greater in the 10% components than in the 100% component. These results were replicated in Experiment 3 in which, instead of extinction, VT schedules replaced the baseline schedules in each multiple‐schedule component during the test. We argue that the relative change in dependency from Baseline to Test, which is greater when baseline dependencies are high rather than low, could account for the differential resistance to change in the present experiments. The inconsistencies in results across the present and previous experiments suggest that the effects of dependency on resistance to change are not well understood. Additional systematic analyses are important to further understand the effects of the response–reinforcer relation on resistance to change and to the development of a more comprehensive theory of behavioral persistence.     

Construct and concurrent validity of the Cambridge neuropsychological automated tests in Portuguese older adults without neuropsychiatric diagnoses and with Alzheimer’s disease dementia

We aimed to analyze the construct and concurrent validity of the Rapid Visual Information Processing (RVP), Paired Associates Learning (PAL), Reaction Time (RTI), and Spatial Working Memory (SWM) tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB®). Inclusion criteria were checked in a first session. The CANTAB and additional pencil-and-paper tests were administered within 1 week. The participants (aged 69–96 years) were 137 Portuguese adults without neuropsychiatric diagnoses and 37 adults with mild-to-moderate Alzheimer’s disease dementia. Comparisons were made between the CANTAB tests and between these tests and the Rey Complex Figure Test (RCFT), Verbal Fluency (VF) test, and some Wechsler Memory Scale-III and Wechsler Adult Intelligence Scale-III subtests. Most intra-test correlations were stronger than the CANTAB inter-test correlations. The RVP correlated more with VF animals (.44), the PAL with RCFT immediate recall (–.52), the RTI with RVP mean latency (.42), and the SWM with Spatial Span backward (–.39).     

The Trait Anxiety Scale for Children: A validation study for European Portuguese children and adolescents

The State-Trait Anxiety Inventory for Children is a self-report instrument inspired on the State-Trait theory extended by Spielberger that measures a momentary state of anxiety (state) and a stable tendency to experience anxiety (trait). This study presents an exploratory adaptation of the Trait Scale and provides its psychometric properties for European Portuguese children and adolescents. The influence of sex and age were also explored. Our sample, composed of 402 participants aged 8–14 years, revealed a mean anxiety value of 28.37 (SD = 5.99). As expected, females revealed higher levels of anxiety than boys. Higher anxiety was obtained in our youngest group as compared to the oldest group. The exploratory factor analysis led to retaining only 16-items that presented acceptable adjustment to a one-factorial solution. Good indexes were obtained in the confirmatory analysis. The results also revealed good internal consistency and good test-retest reliability. Our results provide initial evidence that this scale is adequate to measure trait-anxiety in European Portuguese young people.     

Biotechnologies that empower transgender persons to self-actualize as individuals,partners, spouses,and parents are defining new ways to conceive a child: psychological considerations and ethical issues

Today, thanks to biomedical technologies advances, some persons with fertility issues can conceive. Transgender persons benefit also from these advances and can not only actualize their self-identified sexual identities but also experience parenthood. Based on clinical multidisciplinary seminars that gathered child psychiatrists and psychoanalysts interested in the fields of assisted reproduction technology (ART) and gender dysphoria, philosophers interested in bioethics, biologists interested in ART, and endocrinologists interested in pubertal suppression, we explore how new biotechnical advances, whether in gender transition or procreation, could create new ways to conceive a child possible. After reviewing the various medical/surgical techniques for physical gender transition and the current ART options, we discuss how these new ways for persons to self-actualize and to experience parenthood can not only improve the condition of transgender persons (and the human condition as a whole through greater equity) but also introduce some elements of change in the habitual patterns of thinking especially in France. Finally, we discuss the ethical issues that accompany the arrival of these children and provide creative solutions to help society handle, accept, and support the advances made in this area.