Search results for "learning."
showing 10 items of 6527 documents
Flexible switching of feedback control mechanisms allows for learning of different task dynamics.
2013
To produce skilled movements, the brain flexibly adapts to different task requirements and movement contexts. Two core abilities underlie this flexibility. First, depending on the task, the motor system must rapidly switch the way it produces motor commands and how it corrects movements online, i.e. it switches between different (feedback) control policies. Second, it must also adapt to environmental changes for different tasks separately. Here we show these two abilities are related. In a bimanual movement task, we show that participants can switch on a movement-by-movement basis between two feedback control policies, depending only on a static visual cue. When this cue indicates that the …
Dosage individualization of erythropoietin using a profile-dependent support vector regression
2003
The external administration of recombinant human erythropoietin is the chosen treatment for those patients with secondary anemia due to chronic renal failure in periodic hemodialysis. The objective of this paper is to carry out an individualized prediction of the EPO dosage to be administered to those patients. The high cost of this medication, its side-effects and the phenomenon of potential resistance which some individuals suffer all justify the need for a model which is capable of optimizing dosage individualization. A group of 110 patients and several patient factors were used to develop the models. The support vector regressor (SVR) is benchmarked with the classical multilayer percept…
The use of control groups in artificial grammar learning.
2003
Experimenters assume that participants of an experimental group have learned an artificial grammar if they classify test items with significantly higher accuracy than does a control group without training. The validity of such a comparison, however, depends on an additivity assumption: Learning is superimposed on the action of non-specific variables—for example, repetitions of letters, which modulate the performance of the experimental group and the control group to the same extent. In two experiments we were able to show that this additivity assumption does not hold. Grammaticality classifications in control groups without training (Experiments 1 and 2) depended on non-specific features. T…
Cerebellar patients demonstrate preserved implicit knowledge of association strengths in musical sequences
2006
Recent findings suggest the involvement of the cerebellum in perceptual and cognitive tasks. Our study investigated whether cerebellar patients show musical priming based on implicit knowledge of tonal-harmonic music. Participants performed speeded phoneme identification on sung target chords, which were either related or less-related to prime contexts in terms of the tonal-harmonic system. As groups, both cerebellar patients and age-matched controls showed facilitated processing for related targets, as previously observed for healthy young adults. The outcome suggests that an intact cerebellum is not mandatory for accessing implicit knowledge stored in long-term memory and for its influenc…
Declarative verbal memory impairments in middle-aged women who are caregivers of offspring with autism spectrum disorders: The role of negative affec…
2015
Caring for offspring diagnosed with a chronic psychological disorder such as autism spectrum disorder (ASD) is used in research as a model of chronic stress. This chronic stress has been reported to have deleterious effects on caregivers' cognition, particularly in verbal declarative memory. Moreover, such cognitive decline may be mediated by testosterone (T) levels and negative affect, understood as depressive mood together with high anxiety and anger. This study aimed to compare declarative memory function in middle-aged women who were caregivers for individuals with ASD (n = 24; mean age = 45) and female controls (n = 22; mean age = 45), using a standardised memory test (Rey's Auditory V…
Adaptive frequency decomposition of EEG with subsequent expert system analysis.
2001
We present a hybrid system for automatic analysis of clinical routine EEG, comprising a spectral analysis and an expert system. EEG raw data are transformed into the time-frequency domain by the so-called adaptive frequency decomposition. The resulting frequency components are converted into pseudo-linguistic facts via fuzzification. Finally, an expert system applies symbolic rules formulated by the neurologist to evaluate the extracted EEG features. The system detects artefacts, describes alpha rhythm by frequency, amplitude, and stability and after artefact rejection detects pathologic slow activity. All results are displayed as linguistic terms, numerical values and maps of temporal exte…
A multi-joint lower-limb tracking-trajectory test for the assessment of motor coordination.
2005
This study aimed to determine whether a lower-limb trajectory-tracking task performed on a leg press machine, that is commonly adopted in both rehabilitation and resistance training settings, could yield reliable assessment of motor coordination in able-bodied individuals. Twenty-two female subjects allocated to two experimental groups were tested and retested after 48-72 h. Group A was fully familiarized with the experimental procedures before each test while group B received only verbal instructions. The unilateral coordination test consisted of target tracking during a simulated half squat including eccentric and concentric actions. In both groups, tracking error showed significant test-…
Constraints representing a meta-stable régime facilitate exploration during practice and transfer of learning in a complex multi-articular task
2018
Previous investigations have shown that inducing meta-stability\ud in behavior can be achieved by overlapping affordances through constraint\ud manipulation, allowing cooperative and competitive tendencies to\ud functionally coexist. The purpose of this paper was to test a number of\ud conditions applying these design principles on performance during skills\ud practice and transfer. Of additional interest, was whether the existing\ud skill level interacted with the environmental properties of the\ud experimental tasks (varying indoor climbing routes). Two skill groups\ud practised on three routes per session over four separate sessions. At the\ud end of the final session, climbers undertook…
Personal conceptions of intelligence, self-esteem, and school achievement in Italian and Portuguese students.
2007
Educational research places emphasis on the fact that different cultures have different self-construals. These construals can influence cognitive, emotional, and motivational processes in individuals. Great importance is attached to individuals' implicit conceptions of the nature of their intelligence (incremental or entity) and self-esteem. In general, both representation of intelligence and self-esteem seem to play an important role in scholastic performance in terms of both a predispostion to learning and the results actually achieved. The aim of this research is to determine the relationship between variables such as school, and socioeconomic level and gender in Italian and Portuguese s…
Attitudes of Primary School Teachers in Three Western Countries Toward Learning Disabilities
2016
In recent years, teachers in Western countries have developed beliefs and attitudes related to working with students with specific learning disabilities (LD) that may be critical in shaping their educational practices with them; however, their beliefs and attitudes differ across political and geographical contexts and may be influenced by specific contextual circumstances and national legislation. This study examines these issues by comparing beliefs and attitudes among 557 primary school teachers from specific areas of three countries (Italy, Spain, and the United States). Results from this study support the hypothesis that, in general, teachers in these areas are sufficiently well inform…