Publications by authors named "Ralf Th Krampe"

Dual-task paradigms can provide insights on the structures and mechanisms underlying information processing and hold diagnostic, prognostic, and rehabilitative value for populations with cognitive deficits such as in individuals with intellectual disability (ID). In this paradigm, two tasks are performed separately (single-task context) and concurrently (dual-task context). The change in performance from single- to dual-task context represents dual-task interference.

View Article and Find Full Text PDF

Background: Athletes with intellectual disability represent a unique population who experiences the contrasting effects of cognitive deficits and benefits of sports on balance. This study investigated the combined impact of intellectual disability and sport practice on balance.

Method: Center-of-pressure excursion in bipedal stance of 2 disability (with and without intellectual disability) × 2 sport practice (athlete and novice) participant groups was measured in several balance conditions.

View Article and Find Full Text PDF

Purpose: We investigated cognitive-motor multitasking in 29 top athletes with intellectual impairment (II) recruited during the European Championship Games organized by Virtus (World Intellectual Impairment Sports) and 29 control (CT) athletes matched for age, sex, sports practiced, and lifetime accumulated practice hours.

Methods: Participants performed a cognitive task that required recognizing previously displayed visual objects among distractors. The motor task required maintaining a stable upright posture balancing on a rocking board placed atop a force plate which assessed center-of-pressure (COP) movement.

View Article and Find Full Text PDF

The high prevalence of postural instability in individuals with intellectual disability (ID) warrants the need for reliable and practical postural control assessments. Stabilometry is a postural control assessment that has been widely used for clinical populations. However, the scant systematic knowledge about the reliability of stabilometric protocols for adults with ID renders results questionable and limits its value for clinicians and researchers.

View Article and Find Full Text PDF

We investigated the influence of image mediation (the process that translates tactile information into a visual image) on the development of haptic two-dimensional (2D) shape identification in 78 participants from five different age groups: preschoolers (4-5 years), first graders (6-7 years), fifth graders (10-11 years), young adolescents (12-13 years), and young adults (18-28 years). Participants attempted to haptically recognize everyday objects (three-dimensional [3D] haptic condition) and tangible line drawings (2D haptic condition) and to recognize objects presented through a serial visual "peek hole" version of the haptic line drawing task (2D visual condition). All groups were excellent at 3D haptic identification.

View Article and Find Full Text PDF

Objectives: Multitasking is a challenging aspect of human behavior, especially if the concurrently performed tasks are different in nature. Several studies demonstrated pronounced performance decrements (dual-task costs) in older adults for combinations of cognitive and motor tasks. However, patterns of costs among component tasks differed across studies and reasons for participants' resource allocation strategies remained elusive.

View Article and Find Full Text PDF

We investigated the applicability of the Gestalt principle of perceptual grouping by proximity in the haptic modality. To do so, we investigated the influence of element proximity on haptic contour detection. In the course of four sessions ten participants performed a haptic contour detection task in which they freely explored a haptic random dot display that contained a contour in 50% of the trials.

View Article and Find Full Text PDF

We conducted a haptic search experiment to investigate the influence of the Gestalt principles of proximity, similarity, and good continuation. We expected faster search when the distractors could be grouped. We chose edges at different orientations as stimuli because they are processed similarly in the haptic and visual modality.

View Article and Find Full Text PDF

We investigated dual-task performance of cognitive (semantic fluency) and sensorimotor tasks (walking) in 120 children and adults from four age groups (9-year olds, M=9.52 years; 11-year olds, M=11.51 years; young adults, M=25.

View Article and Find Full Text PDF

We investigated adult age-differences in timing control of fast vs. slow repetitive movements using a dual-task approach. Twenty-two young (M = 24.

View Article and Find Full Text PDF

We investigated age-related changes in adaptation and sensory reintegration in postural control without vision. In two sessions, participants adapted their posture to sway reference and to reverse sway reference conditions, the former reducing (near eliminating) and the latter enhancing (near doubling) proprioceptive information for posture by means of support-surface rotations in proportion to body sway. Participants stood on a stable platform for 3 min (baseline) followed by 18 min of sway reference or reverse sway reference (adaptation) and finally again on a stable platform for 3 min (reintegration).

View Article and Find Full Text PDF

We investigated adult age differences in dual-task costs in cognitive-sensorimotor settings without concurrent response production and with individually adjusted resource demands for the cognitive task. Twenty-four young adults (M=25.42 years, SD=3.

View Article and Find Full Text PDF

We investigate dynamic posture control and working memory (NBack) retest practice in young and older adults, focusing on older adults' potential for improvement in the component tasks but more importantly in dual-task performance. Participants performed the 2 tasks in 11 sessions under single- and dual-task conditions. Posture improvement was observed with retest practice for both groups.

View Article and Find Full Text PDF

Task prioritization can lead to trade-off patterns in dual-task situations. The authors compared dual-task performances in 9- and 11-year-old children and young adults performing a cognitive task and a motor task concurrently. The motor task required balancing on an ankle-disc board.

View Article and Find Full Text PDF

In older adults, cognitive resources play a key role in maintaining postural stability. In the present study, we evaluated whether increasing postural instability using sway referencing induces changes in resource allocation in dual-task performance leading older adults to prioritize the more age-salient posture task over a cognitive task. Young and older adults participated in the study which comprised two sessions.

View Article and Find Full Text PDF

Objective: With age, the performance of multiple tasks decreases, a pattern exaggerated in Alzheimer disease (AD). At the same time, recent research, based on adaptive theories of healthy aging, indicates a preference of older adults to allocate resources toward tasks of higher immediate value (e.g.

View Article and Find Full Text PDF

The authors demonstrate that the timing and sequencing of target durations require low-level timing and executive control. Sixteen young (M-sub(age) = 19 years) and 16 older (M-sub(age) = 70 years) adults participated in 2 experiments. In Experiment 1, individual mean-variance functions for low-level timing (isochronous tapping) and the sequencing of multiple targets (rhythm production) revealed (a) a dissociation of low-level timing and sequencing in both age groups, (b) negligible age differences for low-level timing, and (c) large age differences for sequencing.

View Article and Find Full Text PDF
Aging, expertise and fine motor movement.

Neurosci Biobehav Rev

November 2002

Age-graded decrements in accuracies and maximum speed of fine motor movements observed in numerous experimental studies have nurtured general factor explanations like the assumption of general age-related slowing of central cognitive processes. This review focuses on two domains of investigation that yielded challenges to general factor models. First, experimental approaches aiming at the decomposition of fine motor skills provide evidence for the dissociability of timing, sequencing, and executive control components that show differential rather than general age-related changes.

View Article and Find Full Text PDF

The control of human hand movements is investigated in a simple synchronization task. We propose and analyze a stochastic model based on nonlinear error correction; a mechanism which implies the existence of unstable periodic orbits. This prediction is tested in an experiment with human subjects.

View Article and Find Full Text PDF