Search results for "learning"
showing 10 items of 6669 documents
Changing associations between cognitive impairment and imaging in multiple sclerosis as the disease progresses.
2013
The authors explored cross-sectional associations between MRI parameters (lesion metrics, brain volumes, magnetization transfer ratio histograms, and metabolite concentrations) and cognition in 61 patients who experienced clinically-isolated syndromes (CIS) 7 years earlier. IQ decline and poorer overall cognition were associated with T2 white-matter lesions, and slow information-processing with both T2 lesions and gray-matter atrophy. In a previous study of the same cohort, gray-matter atrophy measured shortly after CIS failed to predict development of cognitive impairment years later. Our findings suggest that gray-matter pathology, reflected by atrophy measurements, becomes increasingly i…
One-year follow-up of cardiac anxiety syndromes. Outcome and predictors of course.
1987
In a representative sample (n = 31) of patients with panic attacks and a cardiac anxiety syndrome, a prospective follow-up study after a 1-year interval was performed. At the follow-up assessment 33% of the patients were in remission, whereas the majority of patients had an unfavorable course. Avoidance behavior and female sexual status were found to be predictive for an unfavorable course. Within a matched-pair design controlled for age and sex, no difference between panic disorder with and without cardiac anxiety syndrome was observed in any psychosocial or psychopathological outcome variable. This result is an argument against the validity of the subtype cardiac anxiety syndrome.
Motor learning without doing: trial-by-trial improvement in motor performance during mental training.
2010
Although there is converging experimental and clinical evidences suggesting that mental training with motor imagery can improve motor performance, it is unclear how humans can learn movements through mental training despite the lack of sensory feedback from the body and the environment. In a first experiment, we measured the trial-by-trial decrease in durations of executed movements (physical training group) and mentally simulated movements (motor-imagery training group), by means of training on a multiple-target arm-pointing task requiring high accuracy and speed. Movement durations were significantly lower in posttest compared with pretest after both physical and motor-imagery training. …
A reanalysis of the center for epidemiological studies depression scale (CES-D) using non-parametric item response theory
2020
Abstract The “Center for Epidemiological Studies Depression Scale” (CES-D; Radloff, 1977 ) is a questionnaire used world-wide to measure depressive symptoms. Although the original four-factor-structure has been widely accepted and replicated, some studies point to other factor-structures like a one- and two-factor-structure. The goal of the current study was to evaluate the factor structure of the CES-D (one-, two- and four-factor-structure), which was found using classical test theory (CTT), with two non-parametric item-response-theory-models (Mokken-Scaling; Monotone-homogeneity-model; MHM and Double-monotonicity-model; DMM). To this end, a representative German sample was analyzed (N = 2…
Neurocognitive Impairment in Bipolar Patients With and Without History of Psychosis
2008
Objective: Little is known regarding the impact of psychotic symptoms on the cognitive functioning of bipolar patients. Findings from previous reports are controversial and mainly focused on current psychotic symptoms. The main aim of this study was to ascertain whether the history of psychotic symptoms was associated with greater cognitive impairment in euthymic bipolar patients. Method: Sixty-five euthymic bipolar disorder patients (DSM-IV criteria; 35 with a history of psychotic symptoms and 30 without such a history) were assessed through a neuropsychological battery targeting attention, psychomotor speed, verbal memory, and executive functions. Thirty-five healthy controls were also in…
Local staging of rectal carcinoma and assessment of the circumferential resection margin with high-resolution MRI using an integrated parallel acquis…
2005
Purpose To assess the diagnostic accuracy of integrated parallel acquisition technique (iPAT) in local staging of rectal carcinoma in comparison to conventional high-resolution MRI. Materials and Methods A total of 28 patients with a neoplasm of the rectum and 15 control patients underwent MRI of the pelvis. High-resolution images were acquired conventionally and with iPAT using a modified sensitivity encoding (mSENSE). Image quality, signal-to-noise and contrast-to-noise ratios (SNR, CNR), tumor extent, nodal status, and delineation of the circumferential resection margin (CRM) were compared. In 19 patients with a carcinoma, MR findings were correlated with the histopathological diagnosis.…
Course of cognitive deficits in first episode of non-affective psychosis: a 3-year follow-up study.
2013
Abstract Cognitive dysfunctions are critical determinants of the quality of life and functionality in schizophrenia. Whether the cognitive deficits present at an early stage, are static or change across one's lifespan is still under debate. This study aims to investigate the long-term (3 years) course of cognitive deficits in a large and representative cohort of first episode schizophrenia spectrum patients (N = 155),and evaluate their influence on disability. In addition, a healthy control sample (N = 43) was also studied for comparison. This study evaluates the performance of patients and controls in a battery of cognitive assessments using baseline, 1-year and 3-year follow-up designs. T…
The time course of temporal discrimination: An ERP study
2009
Objective: The question of how temporal information is processed by the brain is still a matter of debate. This study aimed to elucidate the brain electrical activity associated with a visual temporal discrimination task. Methods: For this purpose, 44 participants were required to compare pairs of sequentially presented time intervals: a fixed standard interval (1000 ms), and an equal-to-standard, longer (1200 ms) or shorter (800 ms) comparison interval. Behavioural data and event-related potentials (ERPs) were analyzed. Results: Long intervals were more rapidly identified than short intervals. The amplitude of the contingent negative variation (CNV) found at frontocentral sites before the …
Elderly adults delay proprioceptive reweighting during the anticipation of collision avoidance when standing.
2012
The ability to reweight visual and proprioceptive information is critical for maintaining postural stability in a dynamic environment. In this study, we examined whether visual anticipation of collision avoidance (AV) while standing could facilitate the down-weighting of altered proprioception in young and elderly adults. Twelve young (24.91 ± 6.44 years) and 12 elderly (74.8 ± 6.42 years) participants stood upright for 180 s under two task conditions: (a) quiet stance (QS) and (b) standing while anticipating virtual objects to be avoided. In order to disrupt the accuracy of proprioceptive input participants were exposed to bilateral Achilles tendon vibration during the middle 60 s of stand…
Motor imagery training: Kinesthetic imagery strategy and inferior parietal fMRI activation
2017
Motor imagery (MI) is the mental simulation of action frequently used by professionals in different fields. However, with respect to performance, well‐controlled functional imaging studies on MI training are sparse. We investigated changes in fMRI representation going along with performance changes of a finger sequence (error and velocity) after MI training in 48 healthy young volunteers. Before training, we tested the vividness of kinesthetic and visual imagery. During tests, participants were instructed to move or to imagine moving the fingers of the right hand in a specific order. During MI training, participants repeatedly imagined the sequence for 15 min. Imaging analysis was performed…